Hard lump in my upper arm

Ive got a hard 1-4 inch lump in my upper arm about 3 inches below the armpit . Its moveable but seems to be attached to something . My doctor said it could be scar tissue but im still worried . Im a 38 year old male

22 September 2016

Dear John,

Most lumps are harmless and can be a variety of things, from a simple cyst to, rarely, something more serious. They can be caused by infections, inflammation, disease or trauma. It’s important to have all the information to make a diagnosis. So, for example, if there has been no injury near the area where your lump has developed then it’s unlikely to be scar tissue.

A lump like the one you describe could be:

1. Lymph gland
The location of your lump near the lymph glands in your armpit, suggests that this could be a raised lymph gland caused by an infection.

2. Epidermal cyst
These affect the epidermis layer of the skin and are made up of keratin and fat. They are generally found on the face, neck, shoulders, chest and upper body and can be triggered by acne or mild injuries to the skin. Look for a slowly developing cyst with a rounded appearance, often no larger than 5cms in size.

  • Usually not painful unless they are burst or become infected
  • Usually non-cancerous
  • These cysts tend to disappear without treatment but if need be, can be treated with antibiotics, steroid injections or excision.

3. Pilar cyst
This is a keratin filled cyst originating from the outer hair root sheath/hair follicle. Look for these on the scalp and around hairline areas, they can be difficult to distinguish from epidermal cysts in appearance and size.

  • They run in families
  • Non-cancerous
  • Often will disappear without treatment
  • Treatment if needed will be with antibiotics (if infected) or excision.

4. Lipoma
These can grow under the skin as well as internally within the body. Look for a soft, fatty, moveable lump and grow slowly up to a couple of centimetres in size.

  • Usually harmless
  • They can appear on various parts of the body but are less common around the scalp and neck
  • If these lumps grow, become larger or firmer to touch they should be investigated to eliminate the presence of cancerous cells
  • These can often be left, but if treatment is necessary can be excised or removed by cryotherapy.

5. Fibroma
This is a benign tumour that can occur within any organ. Rarely do fibromas become cancerous and they may not need to be removed. Surgery is one option for managing them.

6. Sarcoma
This is a very rare type of cancer that often surrounds body structures and organs. A cure is readily achievable if an early diagnosis is made.

Treatment will depend on diagnosis, so visit your GP who may investigate further with a biopsy or ultrasound.

Answered by the Health at Hand nurses  

Sources and further reading

Skin cyst – NHS Factsheet

Lump or swelling – NHS Factsheet

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