Where are lymph nodes located in the human body. What is the structure of lymph nodes. How do lymph nodes function in the immune system. Why are lymph nodes important for health. When do lymph nodes become enlarged or swollen. How many lymph nodes are in the human body. Can lymph nodes be felt through the skin.

The Lymphatic System: An Overview

The lymphatic system plays a crucial role in human health, comprising lymphatic vessels and lymphoid organs such as the thymus, tonsils, lymph nodes, and spleen. This intricate network serves multiple vital functions:

• Supporting acquired and innate immunity
• Filtering and draining interstitial fluid
• Recycling cells at the end of their life cycle

Fluid that leaks from end-stage capillaries returns to the vascular system via superficial and deep lymphatic vessels. These vessels ultimately drain into two main ducts:

1. The right lymphatic duct
2. The thoracic duct

The right lymphatic duct travels along the medial border of the scalenus anterior muscle, draining lymph from the right upper quadrant of the body. Meanwhile, the thoracic duct begins at the cisterna chyli and has a highly variable anatomy. Both ducts empty into the subclavian arteries at the jugulovenous angle, with the right lymphatic duct draining into the right subclavian artery and the thoracic duct into the left.

Lymph Node Distribution and Quantity in the Human Body

How many lymph nodes are in the human body? An adult typically has approximately 800 lymph nodes distributed throughout various regions. Where are lymph nodes located in the human body? They are commonly found in the following areas:

• Neck
• Axilla (armpit)
• Thorax (chest)
• Abdomen
• Groin

These strategically positioned nodes are typically found at the convergence of major blood vessels. Their primary functions include filtering incoming lymph and playing crucial roles in both infection defense and malignancy detection.

The Structure of Lymph Nodes: A Closer Look

What is the structure of lymph nodes? Lymph nodes have a distinctive kidney-shaped structure and are typically 1 to 2 cm in size. They receive lymph through multiple afferent vessels and, after filtration, release it through one or two efferent vessels. Each node is usually associated with an artery and vein, terminating in a high endothelial venule (HEV).

Key Structural Components of Lymph Nodes

1. Capsule: A dense connective tissue stroma with collagenous fibers that sends trabeculae inward.
2. Subscapular Sinus: The space between the capsule and cortex, allowing lymphatic fluid transportation.
3. Cortex: Composed of an outer B-cell layer and an inner paracortex (T-cell layer).
4. Medulla: The innermost layer containing blood vessels, sinuses, and medullary cords.

Can lymph nodes be felt through the skin? In some areas, such as the neck, groin, and armpit, healthy lymph nodes may be palpable. However, enlarged or swollen lymph nodes are more easily detectable and may indicate an underlying condition.

The Functional Significance of Lymph Nodes in Human Health

How do lymph nodes function in the immune system? Lymph nodes serve as crucial components of both the innate and adaptive immune responses. Their primary functions include:

• Filtering interstitial fluid collected from soft tissues
• Returning filtered fluid to the vascular system
• Exposing T-cells and B-cells to a wide range of antigens
• Facilitating the activation of antigen-specific B and T cells

Why are lymph nodes important for health? These small yet powerful structures act as surveillance outposts for the immune system, constantly monitoring for potential threats and initiating appropriate immune responses when necessary.

The Role of Lymph Nodes in Immune Response and Disease Detection

Lymph nodes play a critical role in the body’s defense against infections and in the detection of malignancies. When the immune system encounters a pathogen or abnormal cells, lymph nodes often become enlarged as they work to mount an appropriate response.

Lymph Nodes in Infection

When do lymph nodes become enlarged or swollen during infection? Lymph nodes may swell in response to various types of infections, including:

• Bacterial infections
• Viral infections
• Fungal infections
• Parasitic infections

This swelling, known as lymphadenopathy, is often localized to the area of infection. For example, a throat infection may cause swollen lymph nodes in the neck, while a skin infection on the leg might result in swollen nodes in the groin area.

Lymph Nodes and Cancer Detection

How do lymph nodes help in detecting cancer? Lymph nodes can be crucial indicators of cancer spread, particularly in solid tumors. Cancer cells can break away from the primary tumor site and travel through the lymphatic system, often getting trapped in nearby lymph nodes. This process, known as lymphatic metastasis, is why doctors often check lymph nodes during cancer screenings and staging.

Embryological Development of Lymph Nodes

The formation of lymph nodes begins early in fetal development. Key stages in this process include:

1. Mesenchymal condensation forming a lymph sac
2. Development of the T-cell region around the 13th gestational week
3. Appearance of interdigitating reticulum cells in the paracortical lymph node region by the 17th gestational week

This complex developmental process ensures that by birth, infants have a functional lymphatic system ready to defend against pathogens and support overall health.

Clinical Significance of Lymph Nodes in Medical Practice

Understanding lymph node anatomy and function is crucial for medical professionals across various specialties. Why are lymph nodes important in clinical practice? They serve several key purposes:

• Diagnostic tool: Enlarged or abnormal lymph nodes can indicate various conditions, from infections to malignancies.
• Staging cancer: The presence or absence of cancer cells in lymph nodes is often crucial for determining the stage and prognosis of many cancers.
• Treatment planning: Knowledge of lymph node drainage patterns is essential for planning surgeries and radiation therapies.
• Monitoring treatment response: Changes in lymph node size and characteristics can indicate how well a treatment is working.

How do medical professionals assess lymph nodes? Various techniques are employed, including:

1. Physical examination: Palpating accessible lymph nodes to check for size, consistency, and tenderness.
2. Imaging studies: Ultrasound, CT scans, and MRI can provide detailed views of internal lymph nodes.
3. Biopsy: Sampling lymph node tissue for microscopic examination to diagnose specific conditions.
4. Sentinel lymph node mapping: Used in cancer staging to identify the first lymph node(s) to which cancer is likely to spread.

Maintaining Lymph Node Health: Lifestyle and Preventive Measures

While lymph nodes are primarily part of the body’s internal defense system, certain lifestyle choices can support overall lymphatic health. What can individuals do to promote healthy lymph node function?

• Stay hydrated: Adequate fluid intake helps maintain proper lymph flow.
• Exercise regularly: Physical activity, especially movement that involves muscle contractions, can help stimulate lymph flow.
• Maintain a healthy diet: A balanced diet rich in nutrients supports overall immune function, including that of lymph nodes.
• Practice good hygiene: Proper hygiene can help prevent infections that might strain the lymphatic system.
• Avoid tight clothing: Overly tight garments, especially around areas with many lymph nodes (like the groin or armpits), can potentially impede lymph flow.
• Manage stress: Chronic stress can negatively impact the immune system, including lymph node function.

By incorporating these habits into daily life, individuals can support their lymphatic system and overall health.

Self-Examination and Awareness

While routine self-examination of lymph nodes is not typically recommended for the general population, being aware of one’s body and any changes is important. When should someone be concerned about their lymph nodes? Potential red flags include:

• Persistent swelling lasting more than two weeks
• Painless, hard, or fixed lymph nodes
• Lymph nodes that continue to grow over time
• Swollen lymph nodes accompanied by unexplained weight loss, fever, or night sweats

If any of these signs are present, it’s advisable to consult a healthcare professional for proper evaluation.

Future Directions in Lymph Node Research and Medicine

As our understanding of the lymphatic system continues to grow, new avenues for research and medical applications are emerging. What are some promising areas of lymph node research?

• Immunotherapy: Harnessing the power of lymph nodes to enhance cancer treatments.
• Lymphatic drug delivery: Developing targeted therapies that utilize the lymphatic system for more efficient drug distribution.
• Artificial lymph nodes: Creating bioengineered lymph nodes for transplantation or to enhance immune responses.
• Advanced imaging techniques: Improving our ability to visualize and assess lymph nodes non-invasively.
• Lymphedema treatments: Developing new approaches to manage and prevent lymphatic system disorders.

These areas of research hold promise for improving our ability to diagnose, treat, and prevent a wide range of diseases involving the lymphatic system.

Integrating Lymph Node Knowledge Across Medical Specialties

As our understanding of lymph nodes deepens, how can this knowledge be better integrated across medical specialties? Some potential approaches include:

1. Enhanced medical education: Incorporating more comprehensive lymphatic system training in medical curricula.
2. Interdisciplinary collaboration: Encouraging cooperation between oncologists, immunologists, surgeons, and other specialists to leverage lymph node knowledge.
3. Personalized medicine: Utilizing individual lymphatic system characteristics to tailor treatments and prevention strategies.
4. Public health initiatives: Increasing awareness of lymphatic health among the general population.

By taking a holistic approach to lymph node health and function, the medical community can continue to improve patient outcomes and overall public health.

Anatomy, Lymph Nodes – StatPearls

Introduction

The lymphatic system is composed of lymphatic vessels and lymphoid organs such as the thymus, tonsils, lymph nodes, and spleen. These assist in acquired and innate immunity, in filtering and draining the interstitial fluid, and recycling cells at the end of their life cycle. The fluid that leaks from end-stage capillaries returns to the vascular system via the superficial and deep lymphatic vessels, which in turn drain into the right lymphatic duct and the thoracic duct. The right lymphatic duct travels on the medial border of the scalenus anterior muscle and drains the lymph from the right upper quadrant of the body. The thoracic duct starts at the cisterna chyli and has highly variable anatomy. The right lymphatic duct and the thoracic duct drain into the right and left subclavian arteries, respectively, at the jugulovenous angle.[1]

Lymph nodes are found at the convergence of major blood vessels, and an adult will have approximately 800 nodes commonly sited in the neck, axilla, thorax, abdomen, and groin. These filter incoming lymph and play a role in infection as well as in malignancy. This paper will discuss the structure and function of lymph nodes, as well as the anatomical divisions of these.

Structure and Function

Lymph nodes are kidney-shaped and receive lymph via multiple afferent vessels, and filtered lymph then leaves via one or two efferent vessels. Nodes typically have an associated artery and vein, which terminates into a high endothelial venule (HEV). The HEV is the site of trans-endothelial migration of circulating lymphocytes due to T and B-cell endothelial surface receptors.[2]

Lymph nodes usually range in size from 1 to 2 cm and are enclosed in an adipose tissue capsule. Normal size depends upon location, as well as the axis which is being measured. The long axis should be 1 cm or less. They are considered pathological if they lose their oval shape, if there is a loss of the hilar fat, if there is an asymmetrical thickening of the cortex and if they are persistently enlarged. [3]

Lymph Node Structure
[4]

Capsule

The capsule of the lymph node is dense connective tissue stroma and collagenous fibers. The capsule sends trabeculae inside the lymph node, which pass inward, radiating towards the center.

Subscapular Sinus

The subcapsular sinus is the space between the capsule and the cortex, which allows the transportation of the lymphatic fluid.; this is also called the lymph path, the lymph sinus, or the marginal sinus.  The subcapsular sinus is present beneath the capsule and is traversed by both reticular fibers and cells. It receives the afferent vessels, continues with the trabecular sinuses, and joins the medullary sinus in the medulla of the lymph node. 

Cortex

The cortex of the lymph node is the layer beneath the subcapsular sinus. The cortex is formed of the outer cortex and the inner part known as the paracortex. The outer cortex layer is also named the B-cell layer, is rich in CXCR5 chemokines, and consists mainly of B-cells arranged into follicles. The immature B-cells develop into a germinal center when challenged with an antigen. Following this, resting B-cell and dendritic cells surround the germinal center to form a mantle zone. The paracortex layer, also called the T-cell layer, consists of T-cells that interact with the dendritic cells and is rich in CCR7 chemokines.[5]

Medulla

The medulla is the innermost layer of the lymph node and contains large blood vessels, sinuses, and medullary cords. The medullary cords contain antibody-secreting plasma cells, B-cells, and macrophages. The medullary sinuses (or sinusoids) are vessel-like spaces that separate the medullary cords. The medullary sinuses receive lymph from the trabecular sinuses and cortical sinuses and contain reticular cells and histocytes. The medullary sinus drains the lymph into the efferent lymphatic vessels.

Function of Lymph Node
[6]

The primary function of lymph nodes is filtering interstitial fluid collected from soft tissues and eventually returning it to the vascular system. Filtering this exudative fluid allows for exposure of T-cells and B-cells to a wide range of antigens. For antigen-specific B and T cells to activate, they must first suffer exposure to antigens with the aid of antigen-presenting cells, dendritic cells, and follicular dendritic cells. These form part of both the innate immune response and play a role in adaptive immunity.

Embryology

Lymph nodes begin their development in utero as mesenchymal condensation, which later bulges to form a lymph sac. At the 13th gestational week, the T-cell region begins to develop, and by the 17th gestation week, the interdigitating reticulum cells (a subtype of T-cells) are found in the paracortical lymph node region, surrounded by lymphoid cells. B-cell regions within lymph nodes start their development at the 14th gestation week at the marginal sinus with a population of dendritic reticulum cell precursors, lymphoblasts, immunoblasts, and plasmablasts. By the 20th gestation week, incipient primary follicles are observable in the outer cortex containing lymphocytes. During the 12th and 14th gestation weeks, lymph nodes undergo granulopoiesis and erythropoiesis to produce undifferentiated blast cells, monocytes, and macrophages temporarily.[7][8]

Blood Supply and Lymphatics

Lymph Nodes of the Head and Neck

The lymph nodes in the head and neck are paired and broadly split into superficial and deep nodes.

Superficial

Deep

In terms of anatomical dissection, these more easily split into levels of the neck.[9]

Level I

• Level Ia (submental nodes) – anteriorly, in the midline between the anterior bellies of the paired digastric muscles

• Level Ib (submandibular nodes) – in the submandibular triangle, as described above.

Level II

These nodes, also called the upper internal jugular nodes, are found in an anatomical area bounded by the base of the skull superiorly, the hyoid bone inferiorly, the submandibular gland anteriorly, the posterior border of the sternocleidomastoid muscle laterally, and the internal carotid artery medially. The spinal accessory nerve separates the level IIa and IIb nodes.

• Level IIa (jugulo-digastric nodes) – superficial or anterior to internal jugular vein

• Level IIb – deep or posterior to the internal jugular vein

Level III

These nodes are also names the middle internal jugular nodes and are bound superiorly by the hyoid bone, the cricoid cartilage inferiorly, the anterior edge of the sternocleidomastoid muscle anteriorly,  the posterior margin of the sternocleidomastoid muscle, and the common carotid artery medially.

Level IV

These nodes are also named the lower internal jugular nodes and include Virchow’s node. The anatomical area in which they are found is bound superiorly by the cricoid cartilage, the clavicle inferiorly, the sternocleidomastoid muscle anteriorly, and the common carotid artery medially.

Level V

These are also named the posterior triangle nodes and are bounded by the convergence of the sternocleidomastoid and trapezius muscles superiorly, the clavicle inferiorly, the sternocleidomastoid muscle anteriorly and medially, and the trapezius muscle posteriorly.

• Level Va – superior to the cricoid cartilage and include the spinal accessory nodes

• Level Vb – inferior to the cricoid cartilage and include the transverse cervical nodes and  the supraclavicular nodes

Level VI

This level is also named the anterior compartment and contains the anterior jugular, pre-tracheal, para-tracheal, pre-cricoid, pre-laryngeal, and thyroid nodes. It is bound superiorly by the hyoid bone, inferiorly by the suprasternal notch, by the platysma muscle anteriorly, and the common carotid artery laterally.

Lymph Nodes of the Upper Limb

The deep and superficial lymphatics in the upper limb eventually drain into the axillary nodes. However, there are supratrochlear and cubital lymph nodes at the level of the elbow, brachial lymph nodes, and deltopectoral lymph nodes. The drainage of the upper limbs is particular due to the presence of sentry or sentinel lymph nodes. These are usually larger than the rest of the lymph nodes and are the first to filter the incoming lymph. However, it is not uncommon for multiple smaller sentry lymph nodes to also be present.[10][11]

Axillary Nodes

• Lateral nodes (humeral) – These are found posterior to the axillary vein and are the primary draining nodes for the upper limb.

• Central nodes – These are found close to the 2nd part of the axillary artery and receive lymph from the anterior, posterior, and lateral nodes.

• Apical nodes – These are located near the 1st part of the axillary artery and vein and filter the lymph received from the central axillary nodes and the cephalic vein.

The apical nodes further form the subclavian lymphatic trunk, which then drains into the right lymphatic duct.

Lymph Nodes of the Lower Limb

The superficial and deep lymphatic vessels of the lower limb drain into the inguinal lymph nodes in the femoral triangle. This anatomical region, also named Scarpa’s triangle, is bounded by the inguinal ligament above, the medial border of the sartorius muscle laterally, and the medial border of the adductor longus muscle medially. [12][13]

Inguinal Nodes

The inguinal lymph nodes split at the level (where the great saphenous vein becomes the deep femoral vein) into sub-inguinal lymph nodes below and superficial inguinal nodes above.[3]

• Superficial inguinal nodes – These nodes are traditionally found immediately inferior to the inguinal ligament and drain the perineal area (penis, scrotum, perineum), the gluteal region, and part of the abdominal wall.

 Iliac Nodes:[14]

Clinical Significance

The lymphatic system is involved in infective, inflammatory, and malignant diseases, and as such, enlargement of lymph nodes can be attributed to multiple causes. In the case of lymphadenopathy of unclear origin, endoscopic ultrasound (EUS) with or without fine-needle aspiration (FNA) can aid in diagnosis.[15] This diagnostic technique has been shown to have high accuracy with up to 85% sensitivity and 100% specificity and is key in detecting and staging malignancy. [16] With lymph nodes that are out of the scope of fine-needle sampling, elastography plays an increasingly important role, similar to obtaining a virtual biopsy.[17] Functional and anatomical data can be acquired using more traditional diagnostic methods such as positron emission tomography (PET) combined with computed tomography. However, this is commonly a whole-body imaging technique and therefore involves high doses of ionizing radiation. Despite the recent advancements in imaging modalities, the diagnosis still heavily relies on clinical correlation with symptoms.

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Figure

Lymphatic System, Cervical lymph nodes, Lymphatics of the mammary gland, Cisterna chyli, Lumbar lymph nodes, Pelvic lymph nodes, Lymphatics of the lower limb, Thoracic duct, Thymus, Axillary lymph nodes, Spleen, Lymphatics of the upper limb, Inguinal (more…)

Figure

Deep Cervical Lymph nodes, Principal gland of tongue, Supraomohyoid gland, Central trunk, Interrupting nodule, Trunks from margin of tongue, Submental gland, Vessels from apex, Vessels from margin of tongue, Vessels from root of tongue. Contributed by (more…)

Figure

Axillary lymph nodes, Deltoideo Pectoral glands, lateral group, Subclavicular group, Central group, Subscapular group, Pectoral group, Cutaneous collecting trunk fro the thoracic wall, Cutaneous collecting trunks, Subareolar plexus, Pectoral group, Mammary (more…)

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Girard JP, Springer TA. High endothelial venules (HEVs): specialized endothelium for lymphocyte migration. Immunol Today. 1995 Sep;16(9):449-57. [PubMed: 7546210]

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Bontumasi N, Jacobson JA, Caoili E, Brandon C, Kim SM, Jamadar D. Inguinal lymph nodes: size, number, and other characteristics in asymptomatic patients by CT. Surg Radiol Anat. 2014 Dec;36(10):1051-5. [PubMed: 24435023]

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Elmore SA. Histopathology of the lymph nodes. Toxicol Pathol. 2006;34(5):425-54. [PMC free article: PMC1892634] [PubMed: 17067938]

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Baldazzi V, Paci P, Bernaschi M, Castiglione F. Modeling lymphocyte homing and encounters in lymph nodes. BMC Bioinformatics. 2009 Nov 25;10:387. [PMC free article: PMC2790470] [PubMed: 19939270]

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Markgraf R, von Gaudecker B, Müller-Hermelink HK. The development of the human lymph node. Cell Tissue Res. 1982;225(2):387-413. [PubMed: 6980711]

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Cupedo T. Human lymph node development: An inflammatory interaction. Immunol Lett. 2011 Jul;138(1):4-6. [PubMed: 21333686]

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Grégoire V, Ang K, Budach W, Grau C, Hamoir M, Langendijk JA, Lee A, Le QT, Maingon P, Nutting C, O’Sullivan B, Porceddu SV, Lengele B. Delineation of the neck node levels for head and neck tumors: a 2013 update. DAHANCA, EORTC, HKNPCSG, NCIC CTG, NCRI, RTOG, TROG consensus guidelines. Radiother Oncol. 2014 Jan;110(1):172-81. [PubMed: 24183870]

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Suami H, Taylor GI, Pan WR. The lymphatic territories of the upper limb: anatomical study and clinical implications. Plast Reconstr Surg. 2007 May;119(6):1813-1822. [PubMed: 17440362]

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Cuadrado GA, de Andrade MFC, Akamatsu FE, Jacomo AL. Lymph drainage of the upper limb and mammary region to the axilla: anatomical study in stillborns. Breast Cancer Res Treat. 2018 Jun;169(2):251-256. [PubMed: 29380209]

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Pan WR, Wang DG, Levy SM, Chen Y. Superficial lymphatic drainage of the lower extremity: anatomical study and clinical implications. Plast Reconstr Surg. 2013 Sep;132(3):696-707. [PubMed: 23985641]

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Pan WR, Levy SM, Wang DG. Divergent lymphatic drainage routes from the heel to the inguinal region: anatomic study and clinical implications. Lymphat Res Biol. 2014 Sep;12(3):169-74. [PubMed: 25229435]

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Hsu MC, Itkin M. Lymphatic Anatomy. Tech Vasc Interv Radiol. 2016 Dec;19(4):247-254. [PubMed: 27993319]

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Hocke M, Ignee A, Dietrich C. Role of contrast-enhanced endoscopic ultrasound in lymph nodes. Endosc Ultrasound. 2017 Jan-Feb;6(1):4-11. [PMC free article: PMC5331842] [PubMed: 28218194]

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Eloubeidi MA, Chen VK, Eltoum IA, Jhala D, Chhieng DC, Jhala N, Vickers SM, Wilcox CM. Endoscopic ultrasound-guided fine needle aspiration biopsy of patients with suspected pancreatic cancer: diagnostic accuracy and acute and 30-day complications. Am J Gastroenterol. 2003 Dec;98(12):2663-8. [PubMed: 14687813]

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Disclosure: Iulia Bujoreanu declares no relevant financial relationships with ineligible companies.

Disclosure: Vikas Gupta declares no relevant financial relationships with ineligible companies.

Lymph Nodes & Cancer | What are Lymph Nodes?

• What is the lymph system?
• Cancer in the lymph nodes
• Effects of removing lymph nodes

What is the lymph system?

The lymph (or lymphatic) system is a part of your body’s immune system. It includes a network of lymph vessels and lymph nodes. Lymph vessels are a lot like the veins that collect and carry blood through the body. But instead of carrying blood, these vessels carry the clear watery fluid called lymph. Lymph fluid also contains white blood cells, which help fight infections.

Lymph fluid would build up and cause swelling if it were not drained in some way. Lymph vessels draw up the lymph fluid from around the cells to send it towards the chest. There, lymph fluid collects into a large vessel that drains into a blood vessel near the heart.

Lymph nodes and what they do

Lymph vessels send lymph fluid through nodes throughout the body. Lymph nodes are small structures that work as filters for foreign substances, such as cancer cells and infections. They contain immune cells that can help fight infection by attacking and destroying germs that are carried in through the lymph fluid. Lymph nodes are located in many parts of the body, including the neck, armpit, chest, abdomen (belly), and groin. They contain immune cells that can help fight infection by attacking and destroying germs that are carried in through the lymph fluid.

There are hundreds of lymph nodes throughout the body. Each lymph node filters the fluid and substances picked up by the vessels that lead to it. Lymph fluid from the fingers, for instance, works its way toward the chest, joining fluid from the arm. This fluid may filter through lymph nodes at the elbow, or those under the arm. Fluid from the head, scalp, and face flows down through lymph nodes in the neck. Some lymph nodes are deep inside the body, such as between the lungs or around the bowel, to filter fluid in those areas.

Swollen lymph nodes

When there’s a problem, such as infection, injury, or cancer, lymph nodes in that area may swell or enlarge as they work to filter out the “bad” cells. Swollen lymph nodes (lymphadenopathy) tell you that something is not right, but other symptoms help pinpoint the problem. For instance, ear pain, fever, and enlarged lymph nodes near your ear are clues that you may have an ear infection or cold.

Some areas where lymph nodes commonly swell are in the neck, groin, and underarms. In most cases, only one area of nodes swells at a time. When more than one area of lymph nodes is swollen it’s called generalized lymphadenopathy. Some infections (such as strep throat and chicken pox), certain medicines, immune system diseases, and cancers like lymphoma and leukemia can cause this kind of swelling. Your health care provider will look for more information to figure out the cause of the swelling. Lymph node swelling is often caused by something other than cancer.

Cancer in the lymph nodes

Cancer can appear in the lymph nodes in 2 ways: it can either start there or it can spread there from somewhere else.

Cancer that starts in the lymph nodes is called lymphoma. You can read more about lymphoma in Hodgkin Lymphoma and Non-Hodgkin Lymphoma.

More often, cancer starts somewhere else and then spreads to lymph nodes. That is the focus of this section.

How does cancer spread to lymph nodes?

Cancer can spread from where it started (the primary site) to other parts of the body.

When cancer cells break away from a tumor, they can travel to other areas through either the bloodstream or the lymph system. If they travel through the lymph system, the cancer cells may end up in lymph nodes. Most of the escaped cancer cells die or are killed before they can start growing somewhere else. But one or two might settle in a new area, begin to grow, and form new tumors. This spread of cancer to a new part of the body is called metastasis.

In order for cancer cells to spread to new parts of the body, they have to go through several changes. They must become able to break away from the original tumor and attach to the outside wall of a lymph or blood vessel. Then they must move through the vessel wall to flow with the blood or lymph to a new organ or lymph node.

When cancer does spread to lymph nodes, it usually spreads to nodes near the tumor itself. These are the nodes that have been doing most of the work to filter out or kill the cancer cells.

How is cancer in lymph nodes found?

Normal lymph nodes are tiny and can be hard to find, but when there’s infection, inflammation, or cancer, the nodes can get larger. Those near the body’s surface often get big enough to feel with your fingers, and some can even be seen. But if there are only a few cancer cells in a lymph node, it may look and feel normal. Lymph nodes deep in the body cannot be felt or seen. So doctors may use scans or other imaging tests to look for enlarged nodes that are deep in the body. Often, enlarged lymph nodes near a cancer are assumed to contain cancer.

The only way to know whether there is cancer in a lymph node is to do a biopsy. Doctors may remove lymph nodes or take samples of one or more nodes using needles. The tissue that’s removed is looked at under the microscope by a pathologist (a doctor who diagnoses illness using tissue samples) to find out if there are cancer cells in it. The pathologist prepares a report, which details what was found. If a node has cancer in it, the report describes what it looks like and how much was seen.

When a surgeon operates to remove a primary cancer, they may remove one or more of the nearby (regional) lymph nodes as well. Removal of one lymph node is considered a biopsy, but when many lymph nodes are removed, it’s called lymph node dissection. When cancer has spread to lymph nodes, there’s a higher risk that the cancer might come back after surgery. This information helps the doctor decide whether more treatment, like chemo, immunotherapy, targeted therapy or radiation, might be needed after surgery.

What does it mean if there’s cancer in my lymph node?

If cancer is found in one or more lymph nodes, it could mean that more tests are needed to know how far the cancer has spread. This information is used to determine the stage of your cancer and the best treatment options.

For more information on staging, see Cancer Staging, or find your cancer type for more detailed information.

Effects of removing lymph nodes

When lymph nodes are removed, it can leave the affected area without a way to drain off the lymph fluid. Many of the lymph vessels now run into a dead end where the node used to be, and fluid can back up. This is called lymphedema, which can become a life-long problem. The more lymph nodes that are removed, the more likely it is to occur. To learn more about what to look for, ways reduce your risk, and how to manage this side effect, see Lymphedema.

Removing lymph nodes during cancer surgery is highly unlikely to weaken a person’s immune system, since the immune system is large and complex and is located throughout the body.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

American Joint Committee on Cancer. AJCC Cancer Staging Manual, 8th ed. New York: Springer 2017: 715-725.

Liao S, von der Weid PY. Lymphatic system: an active pathway for immune protection. Semin Cell Dev Biol. 2015;38:83–89.

National Institute of Allergy and Infectious Diseases. Overview of the Immune System. Updated December 30, 2013. Accessed at https://www.niaid.nih.gov/research/immune-system-overview on February 23, 2021. 

Last Revised: March 2, 2021

American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.

where they are located, what functions they perform, in what diseases they increase

Inflammation and enlargement of the lymph nodes usually cause discomfort and pain. As a rule, this indicates that an inflammatory process is going on in the body.

What are lymph nodes

Lymph nodes are the most important organs that perform a barrier-filtration function ¹ . Their main function is the biological filter of lymph – a colorless liquid that washes all the tissues and cells of the body. It consists of plasma and formed elements. Interestingly, lymph plasma has an almost similar chemical structure to blood plasma, but contains fewer proteins ² .

Useful information about lymph nodes

Where are the lymph nodes

Lymph nodes are located almost everywhere. They are arranged in such a way as to become an obstacle in the way of various “garbage”: toxins, viruses, bacteria, parasites, fungi, cancer cells.

Most lymph nodes are located deep under the skin and even near internal organs where they cannot be felt. But some lymph nodes – under the jaw, in the armpits, in the groin – can be palpated even in a healthy, non-inflamed state.

Photo: Shutterstock

Functions of the lymph nodes

As mentioned earlier, the main function of the lymph nodes is barrier-protective function. In these organs of the lymphatic system, protective cells of the body are formed, such as lymphocytes, antibodies, phagocytes. Lymph nodes protect against the penetration of infections, and also prevent the reproduction of malignant tumor cells and play a role in the immune response to substances foreign to the body.

Lymph nodes also perform the following functions:

• hematopoietic – after the lymph nodes, lymph enriched with lymphocytes enters the blood;
• drainage – promote the outflow of excess fluid;
• depositing (reserve) – a lymph node is a temporary storage of lymphocytes and lymph. The latter lingers in the lymph node in order to ensure the unloading of the bloodstream in “emergency” situations, for example, during venous congestion;
• metabolic – lymph nodes are involved in the metabolism of fats, proteins, carbohydrates and other substances.

Causes of swollen lymph nodes

Lymph nodes have their own diseases, and most often their inflammation is a reaction to some other disease or condition. Completely different reasons can lead to an increase in lymph nodes (lymphadenopathy). Consider the most common of them.

Local infections

Infection is one of the most common causes of swollen lymph nodes.

— For example, it can be acute respiratory diseases, leading to an increase in regional lymph nodes associated with the area in which inflammation occurs, says general practitioner Oksana Khamitseva.

As a rule, the focus of the disease is located near enlarged lymph nodes. So, with infections of the upper respiratory tract, the lymph nodes in the neck become inflamed, with a sexual infection – in the groin.

Generalized viral and bacterial infections

If only one category of lymph nodes is affected, then they speak of local inflammation. If the nodes that are not adjacent to each other increase, then we are talking about a generalized inflammation of the lymph nodes.

This widespread inflammation can be caused by infections – bacterial, viral, fungal, which affect the entire body. It can be tuberculosis, some infectious skin diseases, rubella, chickenpox, cytomegalovirus, mononucleosis, HIV and others.

Autoimmune diseases

Autoimmune connective tissue diseases such as arthritis and systemic lupus erythematosus can also cause swollen lymph nodes. In such diseases, the body begins to attack its own cells. Due to the increasing load on the lymph nodes, their inflammation occurs.

Tumor processes

Swollen lymph nodes can also signal tumor processes in the body. As we wrote above, lymph nodes prevent the reproduction of cancer cells, but in some cases, tumor cells can get stuck in them and multiply. Tumor processes can lead to the development of leukemia, lymphogranulomatosis, lymphoma.

Hypersensitivity of the body

Allergic reactions can also provoke inflammation of the lymph nodes. In addition, their increase may be associated with hypersensitivity to certain drugs.

How lymph nodes are treated

The treatment of lymphadenopathy is varied and always depends on its cause. An increase in lymph nodes is a signal of inflammation, so you need to look for its focus.

Most often, inflammation of the lymph nodes occurs as a secondary process, that is, a reaction to another disease:

• if this is associated with acute respiratory infections, then it is necessary to treat the respiratory tract infection itself, be it a bacterium or a virus;
• if it is associated with a generalized infection (mononucleosis, HIV), then long-term specific therapy is selected here;
• cat-scratch disease (felinosis) is treated with special antibiotics;
• Sepsis is stopped only in the hospital by intravenous administration of various drugs, including antibiotics, and ionic solutions.
• autoimmune diseases (systemic lupus erythematosus, Kawasaki disease, etc.) are treated by a rheumatologist, prescribing hormones or cytostatics for long courses under constant supervision.

Lymphadenopathy can also be caused by cancer. Conventionally, they can be divided into 3 sections:

1. leukemia, when the primary malignant focus is in the bone marrow;
2. lymphomas, when the foci are located directly in the lymph nodes;
3. metastases, when the focus is located in the internal organ, and cancer cells affect the lymph nodes in the path of lymph outflow.

— In the case of leukemia, a bone marrow transplant is possible. With lymphoma, it is useless to do this, you can only use various options for radiation, chemotherapy, genetic engineering methods. And if lymphadenopathy is caused by metastases, then, as a rule, the tumor of the corresponding organ is removed, entering healthy tissues and capturing the “package” of the affected lymph nodes, says our expert Oksana Khamitseva.

How to maintain the health of the lymphatic system at home

According to physician Oksana Khamitseva, the health of the lymphatic system primarily depends on two components: good lymphatic drainage and normal functioning of the immune system. This is not difficult to achieve:

• regular physical activity;
• avoid tight, constricting clothing;
• smoking and alcohol cessation;
• courses of multivitamins 2 times a year;
• food high in protein and fiber in the diet;
• adequate fluid intake.

Popular questions and answers

General practitioner Oksana Khamitseva answers popular questions about lymph nodes.

Which lymph node is responsible for what?

– Each internal organ is supplied with lymph nodes, arteries and veins. If we talk about those lymph nodes that we can feel:

• Submandibular: increase with rhinitis, pharyngitis, tonsillitis, inflammation of the teeth and gums.
• Cervical: inflamed with acute respiratory infections, conjunctivitis, otitis media.
• Parotid: react to otitis media, acute respiratory infections.
• Occipital: increased with head and neck infections, acute tonsillitis, infectious mononucleosis.
• Axillary: may also be associated with mononucleosis, mastitis, breast cancer, HIV, cat scratch disease.
• Elbows: felinosis, HIV.
• Inguinal: mumps, generalized infections, inflammation of the urogenital organs.

What to do if the lymph nodes are inflamed?

– If you have lymphadenitis, you need to see a doctor, because you do not know what it can be connected with. If you notice an increase in lymph nodes in the head and neck, there are signs of acute respiratory infections (runny nose, sore throat, cough, fever), then you can independently start taking vitamins, antiviral drugs, NSAIDs, symptomatic treatments for colds.

If you notice an increase in lymph nodes, which is objectively not related to the infectious process, then doing something without a doctor’s recommendation can be dangerous. Even taking vitamins, if the process is autoimmune, will spur the immune system to even more aggressive inflammation.

Why is inflammation of the lymph nodes dangerous?

— Complications of lymphadenitis include:

• transfer of infection to nearby tissues: bones, subcutaneous fat, skin;
• blockage by blood clots of veins adjacent to inflamed lymph nodes;
• violation of lymphatic drainage, edema, “elephantiasis” of the limbs.

What can not be done with enlarged lymph nodes?

– If you notice an increase in lymph nodes, then it is strongly not recommended to ignore it, heat or apply ice, make lotions without the permission of a doctor. Also, do not smear with anti-inflammatory ointments (you will reduce one lymph node and decide that you are cured, and if it is an oncology?), squeeze and massage the lymph node.

The patient does not know in which direction the lymph flows from this or that lymph node, and if you make the wrong movements, stagnation can be provoked.

Which doctor treats lymph nodes?

— All roads lead to a therapist. After examination and examination, a specialist can identify what lymphadenitis is associated with, treat acute respiratory infections or refer to an ENT doctor, an infectious disease specialist if an infectious process is detected. If an autoimmune disease is detected, your doctor is a rheumatologist, and in case of suspicion of leukemia or lymphoma, an oncologist.

Sources:

1. Semioshko N.V. Lymph nodes adjacent to the celiac trunk // BBC 28.706 Ya431 V 38. – 2014. – P. 111. http://sno.grsmu.by/conference/mk47.pdf#page=111
2. Pogrelchuk O.E., Danko E.S. Blood and lymph. Hematopoiesis // In the world of scientific discoveries. – 2018. – S. 219-221. https://www.elibrary.ru/download/elibrary_36443065_39723184.pdf
3. Dvoretsky L.I. Differential diagnosis in lymphadenopathy // Handbook of a polyclinic doctor. – 2005. – no. 2. – S. 3-10. https://www.elibrary.ru/item.asp?id=18967212

What are lymph nodes and what to do if they are enlarged?

Lymph nodes allow lymph to pass through, retaining and destroying bacteria, viruses and malignant cells. Sometimes they increase, which raises many questions.

Let’s figure out what lymph nodes are, how they are arranged and why, when they increase, you can not follow the advice from the Internet.

What are lymph nodes and why are they needed?

Lymph node is a peripheral organ of the immune system, located on the path of lymphatic vessels from organs and tissues.

Lymph is the liquid part of the blood that is filtered into the intercellular space through the walls of the capillaries. It is rich in proteins, electrolytes and water. It is impossible to lose these valuable substances, and it is impossible to return them back to the blood vessels through the wall. The “filtrate” of the blood enters the lymphatic system, from where it enters the superior vena cava through a network of vessels, that is, it returns to the bloodstream.

Along the course of the lymphatic vessels there are lymph nodes – rounded formations the size of a pea. At its core, a lymph node is an accumulation of protective cells – lymphocytes and macrophages – on a “frame” of connective tissue. Lymph nodes allow the flow of lymph through them, and the protective cells that make up them delay and destroy foreign agents (bacteria, parasites, viruses, tumor cells) that have entered the human body.

That is why the lymph nodes are called biological filters, and they themselves resemble knight’s castles, located in the most important directions of medieval states and protecting them from enemy attacks.

Classification of lymph nodes

There are approximately 500 lymph nodes in the human body. They are located mainly in groups. Each group receives lymph from a specific area of ​​the body or part of an organ. There are many classifications of lymph nodes, the simplest of them is a classification based on localization. There are no lymph nodes in the brain and spinal cord, bones, and the area of ​​the hands and feet.

Swollen lymph nodes: symptom or disease?

Swollen lymph nodes, or lymphadenopathy, is a symptom of a large number of diseases. This is not an independent disease, but only one of its symptoms, such as headache or fever.

Doctors have many classifications of lymphadenopathy. In this article, we will give only a couple of the main ones that will help in understanding the stated problem.

Depending on the extent of the process, lymph node enlargement can be local and generalized ¹ . In the first case, the lymph nodes of 1-2 adjacent anatomical regions increase. For example, submandibular and cervical. In the second case, there is an increase in lymph nodes in two or more non-adjacent, located far from each other, zones. For example, in the inguinal and axillary regions.

The duration of lymph node enlargement can be short (less than 2 months) and protracted (more than 2 months) ¹ .

Why do lymph nodes enlarge?

Swollen lymph nodes can be a symptom of both a relatively harmless disease and a very serious disease. Therefore, you need not to self-medicate, but to look for the cause. And this is the prerogative of the doctor.

Here are just some of the possible causes of swollen lymph nodes:

• infectious diseases . The entry of an infectious agent (virus, bacteria) into the lymph node leads to increased blood flow, active division of lymphocytes and enlargement of the lymph node. That is, this process is of a reciprocal protective nature. An increase in lymph nodes is observed with infections of the upper respiratory tract (adenoviral, tonsillitis), infectious mononucleosis, childhood infections (measles, rubella, mumps, chicken pox), cytomegalovirus infection, etc. In acute infectious diseases, an increase in lymph nodes is temporary and is accompanied by other symptoms (fever, general weakness, malaise, cough, runny nose). Also, swollen lymph nodes can be one of the symptoms of HIV infection;
• autoimmune connective tissue diseases . With these diseases, the human immune system does not work quite adequately, which is why the body begins to attack its own cells. An increase in lymph nodes can be observed with rheumatoid arthritis, systemic lupus erythematosus;
• pyoinflammatory processes of the skin, underlying structures and internal organs. Even panaritium or a bad tooth can cause an increase in lymph nodes;
• vaccination . The introduction of a killed pathogen or its parts into the body leads to the development of an immune response. An increase in lymph nodes is not at all uncommon;
• allergic reactions . Taking many medications (antibiotics, anti-inflammatory and lowering blood pressure) may be accompanied by an increase in lymph nodes;
• neoplastic diseases . Enlarged lymph nodes are a common and sometimes the only sign of cancer. In oncological diseases, it can be primary and secondary.

Primary enlargement of lymph nodes

It is observed in tumors that directly affect the lymphatic system – lymphomas. Usually in these cases, the lymph nodes are more than 2 cm in diameter, painless, and their increase occurs against the background of apparent health, which is why the person does not immediately turn to the doctor.

Secondary enlargement of lymph nodes

It is observed in a malignant neoplasm of any localization. For example, with breast cancer, the only sign may be an increase in the lymph nodes in the armpit.

The fact is that as soon as malignant cells find themselves in the intercellular space, they quickly enter the lymphatic capillaries, and from there to the nearest lymph node. There, some of them are destroyed, and some settle and begin to divide, forming a secondary tumor focus.

The division of tumor cells and the increase in the number of protective cells over time leads to an increase in the size of the lymph node. This is a kind of “price” for curbing the growth of a tumor and the spread of tumor cells throughout the body, because if there were no lymph nodes, tumor cells would very quickly enter the bloodstream and give distant metastases.

With local lymphadenopathy, the tumor is detected in about half of the cases, and with generalized lymphadenopathy – in almost 90% of cases ¹ ! Therefore, it is so important to exclude the tumor origin of lymphadenopathy and understand its causes. You should not waste precious time on self-treatment, and if enlarged lymph nodes appear, you should consult a doctor as soon as possible.

What should I do if my lymph nodes are enlarged and which doctor should I visit?

The adult needs to see a GP and the child/teen needs to be taken to see a pediatrician. Usually, a clinical examination and simple studies (general and biochemical blood tests, if necessary, X-ray examination or ultrasound of a certain area of ​​the body) are enough for a specialist to make a preliminary diagnosis and prescribe treatment or refer the patient to a narrower specialist (oncologist, surgeon, rheumatologist, infectious disease specialist) for additional examination.

What not to do when the lymph nodes are “swollen”: breaking stereotypes

Having discovered enlarged lymph nodes, many people, instead of going to the doctor and understanding the causes of what is happening, begin to self-medicate: heat the area of ​​the enlarged lymph node, drink antibiotics, use compresses, etc. Similar advice can be found on the Internet some set.

Should I do it? No way.

Warming the Lymph Node Area

Many people use pan-calcined salt or a freshly boiled egg to warm the swollen lymph node area. This is usually done to reduce pain. But for most patients, this is absolutely impossible. In the presence of an inflammatory process, thermal exposure will lead to vasodilation and increased inflammation, and in the case of a tumor process, it can accelerate cell division. Both will make the situation worse.

Taking antibiotics

There are many people who uncontrollably “treat” any “suspicious” symptoms with antibiotics. Of course, this is wrong. Antibacterial drugs are prescribed only by a doctor and strictly according to indications. In most cases, with an increase in lymph nodes, taking antibiotics is simply not advisable and will not give a positive effect.

Use of compresses, ointments/gels

The result here is the same as when warming up – the situation only gets worse. In addition, there is the danger of chemical burns to the skin.

Cabbage leaf application

Cabbage, of course, contains many vitamins and microelements, but it is completely useless as an anti-inflammatory agent. But before the patient has time to be convinced of this, some time passes – and the delay in treatment can have an extremely adverse effect on the result, especially when it comes to malignant diseases such as lymphomas.

Do not waste time on self-treatment! In most cases, this leads to a loss of time and aggravates the situation. Swollen lymph nodes may be a symptom of a serious illness.