Why does basal cell carcinoma cause skin sore that does not heal?

Basal cell carcinoma begins in basal cells near the bottom of the outer skin layer. As abnormal cells grow, the surface may break down faster than healthy skin can close it. The area can resemble a shiny bump, a pink or scaly patch, a recurring scab, or an open sore that bleeds after minor contact and then returns. It may occur on sun-exposed skin, including the face, ears, scalp, neck, shoulders, or hands. A non-healing sore has many possible causes, so appearance alone cannot diagnose it.

Book a skin examination for a sore that remains, repeatedly crusts, bleeds, or changes. Note when it began, whether it has grown, and whether its colour, border, or surface has altered. Keep the area clean, avoid picking the scab, and protect nearby skin from sun exposure. A clinician may use a close visual examination and, when needed, take a small sample for laboratory assessment. Do not apply strong steroid or acid products unless advised.

Arrange prompt review if the sore is enlarging, repeatedly bleeding, painful, numb, or close to the eye, nose, ear, or mouth. Seek urgent help for bleeding that will not stop with firm pressure, spreading redness with fever, or sudden swelling around the eye. Early assessment can clarify the cause and protect nearby structures.

Ask what features make the lesion concerning, whether a biopsy is needed, and how to care for the area while waiting. Ask how treatment could affect nearby skin and which changes should prompt an earlier review.