Condition

Soft tissue tumours and lipoma

Soft or rubbery lumps you can feel under the skin are most often benign soft tissue lesions — lipoma above all. The great majority are harmless, but certain features call for closer assessment. Telling them apart is a matter of examination and, where needed, the histology report.

What a lipoma is

A lipoma is a benign lesion arising from fat tissue. It usually feels soft and painless, slides freely under the fingers and is not attached to the skin. It is most common on the neck, shoulder, back, arm and abdomen; it can also occur in the breast area and on the chest wall.

Lipomas grow very slowly and may stay the same size for years. Having several at once (lipomatosis) also occurs and is not in itself a sign of danger.

Other lumps under the skin

• Atheroma (epidermoid cyst) — caused by a blocked sebaceous duct. It is attached to the skin and may have a small central dot; when it becomes inflamed it turns red and painful.
• Fibroma — a firm, mobile lesion arising from connective tissue.
• Ganglion cyst — a fluid-filled lump connected to a joint or tendon sheath, typically at the wrist.
• An enlarged lymph node — not a tumour, but it feels similar; in the axilla, neck and groin it needs separate assessment.
• Malignant soft tissue tumours (sarcoma) — rare, but always considered for rapidly growing, deep-seated and large masses.

When to be concerned

The following features suggest a lesion may not simply be a lipoma and call for assessment without delay:

• The mass is larger than 5 cm or is growing quickly
• It is hard, does not move and is fixed to surrounding tissue
• It sits deep, beneath the muscle layer
• It is painful, or accompanied by numbness or loss of strength
• The overlying skin has changed, has broken down or will not heal
• It has come back where a lesion was previously removed

How the assessment works

1. Physical examination

   The size, firmness, mobility, attachment to the skin and tenderness of the mass are assessed. When it appeared and how it has changed is important information.

2. Ultrasound

   In most cases this is the only imaging needed: it shows the internal structure, the margins, the blood supply and the layer the lesion sits in.

3. Further imaging in selected cases

   MRI or CT is used for large, deep or suspicious lesions, and helps to plan the operation.

4. The decision

   A small, typical lipoma causing no symptoms can be monitored. Growth, pain, cosmetic concern or an atypical appearance are indications for removal.

How removal is done

Small, superficial lesions are usually removed under local anaesthesia in a short procedure, and it is normally possible to go home the same day. If the mass is large, deep or in a difficult location, general or regional anaesthesia may be chosen.

The size and position of the incision are planned around both the site of the lesion and the aim of keeping the scar as inconspicuous as possible. With an atheroma, complete removal of the cyst capsule is essential — capsule left behind is the main cause of recurrence.

The removed material is always sent for pathological examination. The result is usually ready within a few working days, and it is that report which establishes the final diagnosis.

Afterwards

• Stitches are removed after 7–14 days, or dissolve by themselves, depending on the type used.
• Keep the area dry for the first few days, then wash it as your surgeon advises.
• Return to heavy physical work and sport depends on the size and site of the incision.
• If there is redness, increasing pain, a fever or discharge from the wound, a review is needed.

Frequently asked questions

Updated: 21 September 2026