Overview

A lump in the armpit, also known as an axillary mass, refers to any abnormal swelling or bump located in the underarm area. These lumps can vary in size, consistency, and tenderness and are usually caused by enlarged lymph nodes, cysts, infections, or other growths. While most armpit lumps are harmless and resolve on their own, some may indicate more serious underlying conditions such as infections, autoimmune disorders, or malignancies like lymphoma or breast cancer. Identifying the cause of the lump through careful examination and investigation is crucial for appropriate treatment and management.

Causes

There are several potential causes of a lump in the armpit, ranging from benign conditions to more serious medical issues. Common causes include:

• Enlarged Lymph Nodes: Often due to local or systemic infections, lymph nodes in the armpit may swell as part of the body’s immune response.
• Bacterial Infections: Conditions like folliculitis or infected sweat glands (hidradenitis suppurativa) can cause painful, swollen lumps.
• Viral Infections: Viral illnesses like mononucleosis or HIV can lead to generalized lymph node enlargement, including the armpit.
• Cysts: Sebaceous cysts or epidermoid cysts are non-cancerous, fluid-filled sacs that can form in the armpit area.
• Lipomas: Benign fatty growths that develop under the skin, usually soft and non-tender.
• Allergic Reactions: Skin irritation from shaving, deodorants, or antiperspirants can cause temporary swelling or lumps.
• Breast Cancer: In some cases, an armpit lump may be the first sign of breast cancer, particularly if cancer has spread to nearby lymph nodes.
• Lymphoma: Cancers of the lymphatic system such as Hodgkin’s or non-Hodgkin’s lymphoma can cause persistent, painless lumps in the armpit.
• Autoimmune Conditions: Diseases like lupus or rheumatoid arthritis may cause lymph node swelling in the armpit.

Symptoms

The symptoms associated with an armpit lump can vary depending on the underlying cause. Common signs and associated symptoms include:

• Swelling or Mass: Noticeable bump or swelling under the skin in the armpit area.
• Tenderness or Pain: Infections typically cause painful lumps, while cancerous lumps are often painless.
• Redness and Warmth: Infected lumps may appear red and feel warm to the touch.
• Skin Changes: Overlying skin may show signs of irritation, rash, or abscess formation.
• Fever: Accompanying fever may indicate an infectious cause.
• Generalized Symptoms: Fatigue, weight loss, night sweats, or persistent fever could point to systemic illnesses like lymphoma or autoimmune diseases.
• Mobility of the Lump: Benign lumps like cysts and lipomas are usually soft and mobile, while malignant lumps may feel hard and fixed in place.

Diagnosis

Diagnosing the cause of a lump in the armpit involves a combination of physical examination, medical history, and diagnostic tests:

• Physical Examination: A doctor will assess the lump’s size, texture, mobility, tenderness, and associated skin changes.
• Medical History: Information on recent infections, vaccination history, trauma, or family history of cancer can provide important clues.
• Blood Tests: May be ordered to look for signs of infection, inflammation, or blood cancers.
• Ultrasound: A non-invasive imaging test used to determine if the lump is solid or fluid-filled.
• Fine Needle Aspiration (FNA): A thin needle is used to extract cells or fluid from the lump for microscopic examination.
• Biopsy: In cases of suspicion for malignancy, a core needle or excisional biopsy may be performed for a definitive diagnosis.
• Mammography: In women, a mammogram may be done to investigate a possible connection to breast cancer.
• CT Scan or MRI: Advanced imaging techniques may be used if cancer or deep tissue involvement is suspected.

Treatment

Treatment of a lump in the armpit depends on the underlying cause and may include:

• Observation: In cases of small, painless, and non-progressive lumps, doctors may recommend observation without immediate treatment.
• Antibiotics: Bacterial infections are treated with oral or intravenous antibiotics, especially when accompanied by redness, warmth, and pain.
• Drainage: Abscesses or large infected cysts may require surgical drainage.
• Surgical Removal: Benign growths like cysts or lipomas can be surgically excised if symptomatic or for cosmetic reasons.
• Cancer Treatment: If malignancy is diagnosed, treatment may include surgery, chemotherapy, radiation therapy, or a combination of these based on cancer type and stage.
• Treatment of Underlying Conditions: Autoimmune diseases may be managed with immunosuppressive therapy or steroids.
• Pain Relief and Supportive Care: Analgesics, warm compresses, and proper hygiene can help ease minor symptoms.

Prognosis

The prognosis of an armpit lump largely depends on the underlying cause:

• Benign Conditions: Most lumps caused by infections, cysts, or lipomas are benign and have an excellent prognosis, especially when treated promptly.
• Infections: With appropriate antibiotics or drainage, infections usually resolve completely without long-term issues.
• Cancerous Lumps: Early detection of malignant causes like breast cancer or lymphoma improves treatment success and survival rates. The prognosis varies depending on cancer type, stage, and overall health of the patient.
• Chronic Conditions: Autoimmune or systemic diseases may cause recurrent or persistent swelling but can be managed effectively with ongoing treatment.

Overall, early diagnosis and timely treatment lead to favorable outcomes in the majority of cases involving armpit lumps. Regular self-examination and medical evaluation of persistent or unusual lumps are crucial for early detection of serious conditions.