What should you know about rare types of melanoma?

Some melanomas begin outside the usual sun-exposed skin, including beneath a nail, on mucosal tissue, or in the eye. Others are uncommon skin patterns. Their signs can be subtle: a dark streak under one nail, a persistent pigmented patch, an unusual sore, or a spot that changes in colour, border, or texture.

The location matters because it affects which specialist examines you and how a sample is taken. A biopsy provides the diagnosis. Further tests may show how deep the lesion is or whether nearby lymph nodes and other organs need checking.

Make an appointment when a mark persists or changes, especially when it is under a nail, inside the mouth, around the eye, or on genital tissue. Bring clear photographs and note when you first noticed the change. Avoid filing a suspicious nail mark away or applying irritating products to it.

Depending on the findings, care can include [Surgical Excision](/treatments/surgical-dermatology/excisional-surgery/), [Tumour Removal Surgery](/treatments/surgical-oncology/tumour-removal-surgery/), a [Sentinel Lymph Node Biopsy](/treatments/diagnostics-and-staging/sentinel-lymph-node-biopsy/), or drug treatment such as [Immunotherapy](/treatments/systemic-therapy/immunotherapy/).

Arrange prompt care for bleeding, ulceration, fast growth, a new lump, or a lesion that interferes with vision, swallowing, or walking. Go to emergency care for sudden vision loss, severe eye pain, breathing difficulty, facial swelling, confusion, or new weakness.

Ask where the melanoma started, whether the biopsy is complete, what staging tests are useful, and which specialist will coordinate care. Ask how treatment may affect appearance, function, or vision, and how follow-up will look after treatment.