Vulvar Melanoma: Molecular Characteristics, Diagnosis, Surgical Management, and Medical Treatment
Authors: Christoph Wohlmuth & Iris Wohlmuth-Wieser
Ten percent of all women have pigmented vulvar lesions. Fortunately, most of these are benign but 1% of all melanomas in women affect the vulva. While the mortality rate of cutaneous melanoma has dropped by 7% annually during the last 5 years, the prognosis of vulvar melanoma remains dismal: the 5-year overall survival rate is 47% compared with 92% for cutaneous melanoma. The current evidence suggests that this likely results from a combination of delayed diagnosis and different tumor biology, treatment strategies, and treatment response. Although many landmark trials on checkpoint inhibitors included mucosal and vulvar melanomas, the results were often not reported separately. Post-hoc analyses indicate overall response rates between 19 and 37% for checkpoint inhibitors. A recently published retrospective study on vulvar melanomas suggests an objective response in 33.3% with a similar safety profile to cutaneous melanoma. Tyrosine kinase inhibitors may be considered in recurrent disease if a c-KIT mutation is present.
Compared with skin melanomas, vulvar melanomas are associated with a poor prognosis resulting from delayed diagnosis and different tumor biology, treatment strategies, and treatment response.
Novel treatment modalities include checkpoint inhibitors and targeted therapies and recent evidence shows that these are also effective in vulvar melanomas.
Vulvar melanomas have a different tumor biology with frequent c-KIT mutations, which provides an additional therapeutic target in recurrent disease.