Melanoma · surgery

Wide local excision for melanoma

Why another operation is often recommended after diagnostic biopsy — even when the pathology report says the biopsy margins are clear.

Biopsy and wide excision have different purposes

An excisional biopsy establishes the diagnosis and supplies key tumour measurements. Wide local excision (WLE) is a treatment step: the biopsy scar and surrounding skin are removed with a clinical margin selected from the pathology and anatomical context.

Clear biopsy margins do not necessarily mean treatment is complete. WLE aims to reduce local recurrence risk according to the thickness of the original melanoma.

Typical margin framework

Melanoma in situOften at least 5 mm; some sites or subtypes may require a wider approach.
Invasive < 1 mmUsually 1 cm.
1–2 mmUsually 1–2 cm, depending on anatomy and clinical context.
> 2 mmUsually 2 cm.

These figures are an educational framework, not an individual prescription. The final plan depends on the complete pathology report, site, previous operation and clinical circumstances.

How SLNB fits in

When sentinel lymph node biopsy is indicated, it is planned before or at the same operation as WLE. Major tissue rearrangement can alter lymphatic drainage, so the sequence should be agreed before the next operation.

When reconstruction is needed

Many wounds can be closed directly. Difficult sites or wider defects may require a local flap or skin graft. Closure is selected after the oncological extent has been defined.

Why there is no “universal” case video here

The archive did not contain a sequence that could honestly represent a complete melanoma WLE without combining different patients. This page therefore uses a language-neutral diagram instead of fabricating a clinical story.

Sentinel node biopsyBreslow thicknessReconstruction

This educational material does not replace clinical examination, a complete pathology report or an individual treatment plan.