Mucosal Melanoma: Stages, Causes, Symptoms, Treatment and Complications

Most melanomas are known to appear on the skin, mucosal melanoma is a type of cancer that occurs in the mucous membrane or the moist surface of the area inside the body.

Melanoma occurs due to abnormal and uncontrolled growth of the cells that cause pigmentation. Mucosal melanomas are not always pigmented and can appear in the eyes, mouth, gastrointestinal tract, neck, head, vagina, vulva, and anus.

About 1 in every 100 cases of melanoma is mucosal melanoma.⁽¹⁾

The staging of mucosal melanoma depends on its location. The location is of three types:

• Head and neck
• Vulvar and vagina
• Anorectal mucosa

The staging of the head and neck and vulva uses AJCC-TNM classification. It is as follows:

• T3: Mucosal disease
• T4A: Moderately advanced disease in which the tumor involves the cartilage, deep soft tissue, or overlying skin
• T4B: It is the advanced stage of the disease that involves the brain, dura, skull base, carotid artery, lower cranial nerves, prevertebral space, masticator space, and mediastinal structures.

Vaginal and anorectal mucosal melanoma does not have any specific type of staging. It has a basic clinical stage classification system used for classifying mucosal melanoma in these areas.

• Stage 1: The disease remains localized
• Stage 2: In this stage, the nodes in the region and the area around get involved.
• Stage 3: The disease gets metastatic and involves distant areas and organs.

The risk of mucosal melanoma increases with age. Also, the risk factors vary with the location of the melanoma.

The risk factors of mucosal melanoma in or around the mouth include:

• Ill-fitting dentures
• Smoking
• Carcinogen in the environment

The risk factor for mucosal melanoma in the area of the vulva or vagina include:

• Genetics
• Viruses
• Chemical irritants
• Chronic inflammatory disease

The risk factor for rectum or anus mucosal melanoma is:

• Human immunodeficiency virus

Symptoms of mucosal melanoma depend on the location of the melanoma. Sometimes due to the symptoms being similar to other conditions, it is often misdiagnosed. For example, mucosal melanoma of the anus or rectum is misdiagnosed as hemorrhoids because the symptoms are very similar.

Symptoms of mucosal melanoma include:

• Head and Neck Areas: Bleeding from the nose, ulcers, bleeding lumps, loss of sense of smell, a discolored area in the mouth, and ill-fitting dentures.
• Anus or Rectal Area: Bleeding, pain, diarrhea, constipation, and presence of a mass.
• Vaginal Area: Vulvar discoloration, itching, bleeding, pain with intercourse, discharge, and a noticeable mass.

Surgery is the first treatment option for mucosal melanoma. It involves the removal of the abnormal cells. After this to make sure the melanoma does not return, chemotherapy or radiation therapy is recommended by the doctor. Sometimes a combination of both is suggested.

Sometimes just either of the two without any other option is suggested. It is when the melanoma is in such an area from where it cannot be removed by surgery.

Immunotherapy is a treatment option in which drugs are given to stimulate the immune system to attack cancer cells.

Targeted therapy is another option in which specific drugs are given that just attack the cancer cells, unlike chemotherapy in which other cells of the body are also affected. The survival rate depends on the location of the melanoma and its stage.

Mucosal melanoma reaching its metastasis stage is the primary complication. At this stage, the treatment options reduce and also the survival rate.

Lack of detection or diagnosis can also complicate the condition.

Complications also result from the treatment procedure, which includes the common complication of surgery, chemotherapy, and radiation therapy. It is important to discuss all the risks and complications before going ahead with any procedure.

Mucosal melanoma is an aggressive melanoma as it is mostly not discovered until it reaches its advanced stages. This limits its treatment options. It is therefore important to be regular with the medical check-ups. Earlier the condition is diagnosed better is the outcome and survival rate.