Lump under the armpit
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A lump under the armpit is a clinical symptom that can have very diverse meanings – from completely benign changes to conditions requiring urgent oncological diagnostics. The axillary region contains numerous lymph nodes, sweat glands (including apocrine glands), fatty tissue, blood vessels, and nerve structures, so the appearance of a swelling in this area is not diagnostically conclusive. Key factors include: the size of the lump, its consistency, tenderness, mobility relative to the underlying tissue, growth rate, and accompanying symptoms. Proper interpretation of this symptom requires clinical insight and, in many cases, imaging and laboratory tests.
Lump under the armpit – what does it mean
In clinical practice, a lump under the armpit most commonly indicates an enlarged lymph node or an inflammatory change in the soft tissues. Axillary lymph nodes respond to infections of the skin of the upper limb, chest, and breast, so their temporary enlargement can be a physiological immune response.
The clinical significance of a lump depends on its characteristics:
- painful, soft, movable – most likely an inflammatory process,
- hard, painless, immobile – suspicious change,
- rapidly growing – requires urgent diagnostics,
- persisting > 3–4 weeks – indication for examination.
General symptoms such as fever, night sweats, weight loss, or chronic fatigue are also significant.
Lump under the armpit – when it is cancer
A lump under the armpit may be cancerous, although statistically it occurs less frequently than benign changes. The most clinically significant are metastases to the axillary lymph nodes, especially in the case of breast cancer, melanoma, and lymphomas.
Features raising oncological concern:
- Hard, stone-like consistency,
- Lack of pain,
- Lack of mobility relative to the underlying tissue,
- Gradual, continuous enlargement,
- Coexistence of changes in the breast or on the skin.
In differential diagnosis, one should consider:
- Lymphomas (Hodgkin's and non-Hodgkin's),
- Metastases of organ cancers,
- Less commonly, primary soft tissue tumors.
Any lump with suspicious features requires urgent imaging and histopathological diagnostics.
Lump under the armpit – common causes
The most common non-neoplastic causes of a lump under the armpit include:
Inflammatory and Infectious Changes
- Reactive enlargement of lymph nodes,
- Bacterial folliculitis,
- Skin and subcutaneous abscesses,
- Inflammation of sweat glands (hidradenitis suppurativa).
Benign Changes
- Epidermal cysts,
- Lipomas,
- Fibromas,
- Post-traumatic hematomas.
Local Factors
- Micro-injuries from shaving,
- Allergic reactions to deodorants,
- Chronic friction or pressure.
The vast majority of these changes are of a benign nature and resolve after causal treatment or spontaneously.
Lump under the armpit - how to treat
Treatment of a lump under the armpit should always be dependent on the cause, rather than just the symptom itself. Attempting to press or puncture the lump on your own is not recommended and can lead to complications.
Management includes:
- short-term observation (in cases of inflammatory features),
- anti-inflammatory treatment or antibiotic therapy,
- dermatological treatment for skin changes,
- imaging diagnostics (armpit ultrasound),
- fine needle or core needle biopsy in cases of suspicious changes.
Lack of improvement after 2-4 weeks of conservative treatment is an indication for further diagnostic investigation.
Treatment of a lump under the armpit
Treatment methods include:
- pharmacological treatment
- antibiotics (in bacterial infections),
- anti-inflammatory drugs,
- immunomodulating treatment in chronic diseases;
- procedural treatment
- incision and drainage of an abscess,
- surgical removal of a cyst or lipoma,
- diagnostic excision of a lymph node;
- oncological treatment (if indicated)
- systemic treatment,
- radiotherapy,
- surgical treatment in accordance with current standards.
Each case of a lump under the armpit should be evaluated individually, maintaining the principle: the longer a change of unclear nature persists, the more urgent the diagnostics.
