Vulvar melanoma is a rare cancer developing in the skin of the vulva, the external female genitalia, including the labia majora, labia minora, and clitoris. As a form of melanoma, it originates from melanocytes, the cells responsible for producing pigment. It is an aggressive cancer that, unlike typical melanomas, arises in mucosal membranes not usually exposed to the sun. This article explores its prevalence, risk factors, and signs for early detection.
Understanding Its Rarity
Vulvar melanoma is a rare malignancy, accounting for a small fraction of all melanoma cases. It represents approximately 1% to 2% of all melanomas diagnosed in women. When considering all cancers that affect the vulva, melanoma makes up about 5% to 10% of these cases, making it the second most common type after squamous cell carcinoma.
Its incidence rate is low, estimated at 0.1 to 0.2 cases per 100,000 women annually. Despite its rarity, its incidence in women over 60 has shown a slight increase, rising by about 2.2% per year between 2000 and 2016. This low prevalence makes research challenging, leading to limited data.
Identifying Risk Factors
Several factors increase the likelihood of developing vulvar melanoma. Age is a significant factor, as it is most commonly diagnosed in postmenopausal women, with a median age of diagnosis around 68 years. The risk increases with age, particularly in women over 60.
Ethnicity plays a role; over 90% of vulvar melanomas occur in white women. While sun exposure is a known risk factor for cutaneous melanomas, it is not considered a causative factor for vulvar melanoma, which originates in mucous membranes. Other factors include a personal or family history of melanoma, and the presence of atypical moles (dysplastic nevi) elsewhere. Genetic predispositions, such as mutations in genes like CDKN2A, CDK4, and MITF p.E318K, are linked to an increased risk.
Recognizing Signs and Early Detection
Early detection is important due to its aggressive nature. Individuals should be aware of vulvar skin changes, as symptoms can be subtle and easily missed, leading to advanced stages.
Common signs include a new lump or growth, which can be flat, raised, or have irregular edges. Changes in skin color are a significant indicator; lesions are often dark brown or black, but can also appear red, pink, white, or have uneven coloring. Other symptoms can include persistent itching, unusual vaginal discharge, non-menstrual bleeding, or localized pain.
Any new or changing mole or lesion on the vulva, especially those exhibiting asymmetry, irregular borders, varied color, or increasing diameter, warrants prompt medical evaluation. Regular self-examination and gynecological check-ups are beneficial for early detection.