Hard round lump under the skin

Some lumps sit within the skin and move slightly under gentle pressure, while others feel fixed or arise from deeper tissue. A boil is often painful and inflamed, sometimes with a visible center. A cyst may have a smooth, rounded outline and can become tender when inflamed. Basal Cell Carcinoma can appear as a persistent skin growth or changing sore, particularly where skin has had substantial sun exposure; it requires professional examination rather than self-diagnosis. A photograph and the date you first noticed the lump can help show whether it is changing.

Avoid picking, squeezing, or repeatedly checking the lump, which can cause irritation. Protect the area from friction and sun, and keep any broken surface gently clean. Book a skin examination if it lasts, enlarges, becomes fixed, returns after settling, or develops crusting, bleeding, or a sore that does not heal. A dermatologist may recommend monitoring, a sample, removal, or an intralesional steroid injection for a suitable inflammatory lesion.

Get prompt care if the lump becomes rapidly painful, hot, swollen, or surrounded by spreading redness, or if you develop fever or pus. Seek urgent help for uncontrolled bleeding, eye involvement, or swelling that affects breathing. A persistent changing lump should be assessed even without discomfort.

Ask whether the lump appears superficial or deep, what features need monitoring, whether a biopsy or imaging is appropriate, and whether an injection or removal would be suitable. Ask how to protect the area while waiting.