A lump under the arm can be concerning, but it’s often caused by something minor and harmless. This article explores the common causes of armpit lumps, when to see a doctor, and what to expect.
Most armpit lumps are due to swollen lymph nodes, a key part of the body’s immune system. Lymph nodes filter out bacteria, viruses, and other harmful substances. When you have an infection or irritation, the lymph nodes in your armpit can enlarge as they work to fight it off. This swelling is usually temporary and resolves on its own.
Common Causes of Armpit Lumps
Several factors can contribute to the development of an armpit lump. Here are some of the most common causes:
Infection
Lymph nodes swell in response to infections, such as a cold, the flu, or a skin infection. This is a normal immune response and usually subsides as the infection clears.
Skin Irritation
Irritated skin from shaving, using deodorants with harsh chemicals, or tight clothing can lead to inflamed hair follicles or cysts. These can form lumps under the arm.
Allergy
Allergic reactions to certain products, like deodorants or soaps, can also cause armpit swelling. Switching to hypoallergenic products might help resolve the issue.
Autoimmune Disorders
Conditions like lupus can cause the immune system to overreact, leading to enlarged lymph nodes throughout the body, including the armpits.
Cancer
While rare, an armpit lump can sometimes indicate cancer. Lymphoma, a cancer of the lymphatic system, can manifest as swollen lymph nodes. Breast cancer can also spread to the lymph nodes under the arm.
When to Seek Medical Attention
Although most armpit lumps are benign, it’s important to consult a doctor if:
- The lump persists for more than a week.
- The lump is hard, immobile, or growing larger.
- You experience accompanying symptoms like fever, night sweats, or unexplained weight loss.
- The lump is painless, as cancerous lumps are often not tender.
- There’s no redness or other signs of infection.
Adrienne Waks, MD
Cancerous vs. Non-Cancerous Lumps
Distinguishing between cancerous and non-cancerous lumps can be challenging. While pain and tenderness often accompany infections, cancerous lumps are usually painless. A cancerous lymph node may feel hard, fixed in place, and have an irregular shape. However, only a medical professional can make an accurate diagnosis.
Armpit Lumps and Vaccines
Vaccines, like the flu or COVID-19 vaccine, can sometimes cause temporary swelling in the lymph nodes near the injection site. This is a normal immune response and typically resolves within a few weeks.
Treatment Options for Cancerous Lumps
If an armpit lump is diagnosed as cancerous, treatment options will depend on the type and stage of cancer. These may include:
- Surgery: To remove the cancerous lymph nodes or tumor.
- Radiation Therapy: To target and destroy cancer cells.
- Chemotherapy: To kill rapidly dividing cancer cells throughout the body.
- Immunotherapy: To harness the body’s immune system to fight cancer.
- Targeted Therapy: To specifically target cancer cells with minimal harm to healthy cells.
Understanding Lymph Node Function
Lymph nodes are essential components of the lymphatic system, a network of vessels and nodes that helps remove waste and fight infection. They act as filters, trapping bacteria, viruses, and other harmful substances. The lymphatic system plays a crucial role in maintaining overall health.
The information in this article is not intended to be a substitute for professional medical advice. If you have concerns about an armpit lump, consult with a healthcare provider for proper diagnosis and treatment.
