Mucosal melanoma: a rare melanoma of the mouth, nose, anus and genital tract

Melanoma starts when pigment-making cells, the melanocytes, grow out of control and become cancerous. Most melanoma starts in the skin, but melanocytes are also found in the mucous membranes, the moist surfaces that line cavities in the body such as the mouth, nose, anus or vagina. Melanoma that starts there is called mucosal melanoma, as Cancer Research UK and Melanoma Focus both explain.

Melanoma Focus stresses that although mucosal and skin melanomas start in the same way, they are very different in their biology and the way they act. Skin melanoma is linked to sun exposure, especially in childhood, but this does not increase the risk of mucosal melanoma. It also says mucosal melanoma is just as common in people with light or dark skin tones.

It is rare: Melanoma Focus puts it at about 1 to 2% of melanoma cases. The NHS melanoma pages concentrate on skin melanoma and note only that rarer types can affect the eyes, soles of the feet, palms of the hands or genitals, so charity sources are the main UK reference for this subtype.

Melanoma Focus divides mucosal melanoma by location. Head and neck mucosal melanomas are the most common and include oral (mouth), sinonasal (the nasal passages and sinuses) and pharyngeal or laryngeal (throat), the last being the least common in the head and neck. The other groups are anorectal, urogenital (the penis, urethra and bladder) and vulvo-vaginal.

Cancer Research UK lists the anus, vagina, penis, vulva, mouth and digestive system among the places it can develop, and says uveal melanoma (of the eye) is a separate type treated in a different way. It also says the treatments for mucosal melanoma depend on which part of the body is affected and the chance of it coming back.

Eye melanoma and acral melanoma, which affects the palms, soles and nails, are different conditions. This page covers melanoma of mucous membranes only.

Symptoms depend on where the tumour is, and Melanoma Focus stresses that they are often similar to those of many other minor conditions. Its examples include a nose bleed that has not stopped after 3 weeks, or a single blocked nostril that does not improve with sinus drops, which can occur with sinonasal melanoma, and which rely on the GP ruling out the many harmless causes.

For anorectal melanoma, Melanoma Focus lists bleeding from the back passage, a change in bowel habit, persistent itching, pain, swelling or a lump, and sometimes an urgent need to empty the bowels. For urogenital tumours it lists bleeding, pain or discomfort, unusual discharge, changes in passing urine, or a swelling, lump or ulcer, and notes that some bladder and urethral tumours have few or no symptoms. For vulvo-vaginal melanoma it lists a lump, a sore area, bleeding and trouble passing urine. In each area the affected skin may be darker, but this is not always the case.

Because these symptoms are common and usually harmless, the practical message is to have persistent or unexplained ones checked rather than waiting. If a GP is concerned, an urgent referral to a specialist clinic such as ENT, colorectal surgery or gynaecology is the usual route.

• A nosebleed that has not stopped after 3 weeks, or one blocked nostril that does not improve, should be assessed by a GP.

• Persistent rectal bleeding, a lump or a change in bowel habit needs a GP review.

• A lump, sore area or bleeding in the vulva or vagina, or unusual discharge or bleeding from the genital area, needs a GP review.

• The NHS advises seeing a GP about a new or unusual mark that has not gone away after a few weeks, including on the palms and soles.

The sources read for this page do not set out a single diagnostic pathway for mucosal melanoma, because it depends on the site. In general the NHS describes how melanoma is investigated: a specialist examines the area and a sample is removed for examination (a biopsy), and if melanoma is confirmed you usually have more tests, which may include a CT or MRI scan, tests to see if it has spread to the lymph nodes, and blood tests, so that the specialists can work out how deep it is and how far it has spread (the stage).

Melanoma Focus says that, as these tumours are rare, you may be referred to a clinician with more expertise in mucosal melanoma and may need to travel to a specialist centre. It also highlights updated mucosal melanoma guidelines presented by a UK specialist at its 2025 patient conference, which suggests that specialist guidance exists for the teams who treat these tumours.

Cancer Research UK lists surgery, radiotherapy, targeted or immunotherapy drugs, and chemotherapy as treatments for mucosal melanoma, and says the drugs used may be different to those used for skin melanoma. The NHS says that for melanoma generally surgery is the main treatment, and that targeted medicines and immunotherapy are sometimes used for melanoma that cannot be treated with surgery or has spread. A sample is usually tested for gene changes before targeted medicines to help decide whether they are likely to work.

Melanoma Focus says mucosal melanomas can be more complicated to treat than skin melanomas, partly because they are often diagnosed later. The site matters: surgery in the nose or genital area has different consequences from surgery on skin, and a specialist team will plan around function as well as cancer control.

The NHS adds that if melanoma cannot be cured, treatment aims to limit the cancer and its symptoms and help you live longer, with a palliative care or symptom control team involved, and that your team will include a clinical nurse specialist as a main point of contact.

Because it is so rare, many people feel isolated. Melanoma Focus runs a helpline staffed by specialist nurses and lists patient stories and a private support group; the NHS also points to the Melanoma Focus helpline for people with melanoma. Your clinical nurse specialist can explain what help is available locally.

In the UK, assessment and treatment run through NHS specialist teams. Some people look for a private second opinion, particularly about immunotherapy or surgical options. If you do, ask for your pathology report, gene test results and scans to be shared so that the NHS and private clinicians work from the same information.