Widespread Vulvar Spindle-cell Melanoma: a Case Report

Background: Vulvar melanoma is the second most prevalent form of malignant tumor in this area after squamous cell carcinoma [Falcicchio G. et al 2022].Due to its delayed diagnosis and distinctive characteristics, vulvar melanomas are inherently more challenging to treat, resulting in a significantly poorer overall survival rate of 47% compared to the 92% observed for cutaneous melanoma [Wohlmuth C. et al 2021].Methods: A case report.Results: A 82-year-old woman complained of a rapidly growing mass on the right brachial side that had appeared three months before.In a regional hospital the tumor was removed and a metastatic melanoma was diagnosed.In our center the examination of skin revealed the presence of a postoperative scar on the right brachium, also, blue-brown plaques varying in diameter (largest 3x2 cm) were observed on both labia majora of the vulva.After the excision of the vulvar plaques, histological examination revealed spindle cell melanoma with ulceration and a mitotic count of 4 cells/ mm.Breslow infiltration was 19.3 mm.The patient had elevated levels of LDH (426 U/L) and S100 (696.07).The C-reactive protein level was 185 mg/dl and showed a progressive increase to 271 mg/ dl.A peripheral lymph node scan showed the pathological lymph nodes in the neck and groin.A whole-body PET/CT scan revealed multiple active masses in the cervical lymph nodes, pectoral muscles, lungs, liver and intra-abdominal muscle wall.BRAF mutation in metastatic melanoma's samples was negative.The multidisciplinary oncodermatology team made the initial diagnosis of advanced vulvar spindle cell melanoma and recommended immunotherapy with nivolumab.Despite a second course of immunotherapy, the patient died due to the extensive nature of the disease.Conclusions: Late diagnosis of melanoma in atypical locations, extent of the disease, age were the most unfavorable prognostic factors of our patient.However, with clinical data showing that nivolumab appears to improve survival, immune checkpoint inhibitors represent an encouraging treatment option for patients with advanced or metastatic mucosal melanoma.