What should you know about early melanoma in situ?

In situ means the abnormal pigment cells have not grown through the deeper skin layers in the sampled area. It may look like a flat, irregularly coloured patch or a changing pigmented mark, although appearance cannot confirm the diagnosis. A biopsy provides the diagnosis and helps the specialist define the area needing treatment. Even when the report says in situ, the edges can be difficult to see, especially on sun-exposed or cosmetically sensitive skin.

Attend the recommended skin-cancer or dermatology appointment and bring the pathology report if you have it. The usual aim is to remove the entire affected area with an appropriate margin; surgical excision or another form of skin cancer surgery may be discussed. A sentinel lymph node biopsy is generally a staging conversation for selected invasive melanomas, not a routine step for a lesion confirmed as in situ. Protect the area from sun and do not try to remove residual pigment yourself.

Contact your clinician promptly if the biopsy site becomes increasingly red, hot, swollen, painful, or produces discharge, or if you develop fever. Before treatment, report a patch that is enlarging, bleeding, crusting, or developing new colours. After removal, ask for review if pigment reappears in or around the scar, since it may need examination rather than home treatment.

Ask whether the biopsy sampled the full area, how the edges will be checked, which procedure is proposed, and what scar changes to expect. Clarify wound care, sun protection, the need for any further staging, and how often your skin should be examined after treatment.