Groin lump under the skin: what to know

A tender, warm lump that enlarges over a short time may be a boil, especially after friction, shaving, or an ingrown hair. A deeper, smooth, mobile lump may have a different cause from a spot attached to the skin surface. Recurrent painful nodules in the groin deserve review because blocked follicles and inflammation can recur. A sore that crusts, bleeds, or fails to heal needs examination; a basal cell carcinoma is one possible skin growth, although many groin lumps are not cancerous.

Do not squeeze, pierce, or repeatedly press the lump. Keep the area clean, avoid shaving over it, and wear clothing that reduces rubbing. A warm, clean compress may be comfortable for a tender superficial spot, but stop if pain or redness increases. Photographing the area and noting its size, tenderness, and duration can help a clinician compare changes. Treatment may range from observation to drainage or a steroid injection into the skin, depending on the diagnosis.

Arrange an examination for any persistent, enlarging, hard, fixed, recurrent, bleeding, or non-healing lump. Seek prompt care for spreading redness, severe pain, pus, fever, or feeling unwell. A rapidly changing skin lesion or a lump that interferes with walking also warrants timely review.

Ask whether the lump appears superficial or deeper, whether it could be a boil or another growth, whether imaging or a sample is needed, and which signs should prompt an earlier follow-up.