Vulval melanoma: a case report on an uncommon malignancy with poor prognosis

Abstract

Vulvar melanoma is a rare and aggressive malignancy of the female genital tract. It predominantly affects older women and is frequently diagnosed late because lesions may be clinically subtle or mistaken for benign vulvar disease. This case report represents a 66 year old postmenopausal woman who with a six-year history of non-foul-smelling, non-blood-stained vaginal discharge and persistent perineal pruritus. Examination revealed a 2×3 cm leukoplakic plaque over the right labium minus. An initial excision biopsy showed mild dysplasia, while repeat biopsy six months later demonstrated focal severe dysplasia. Magnetic resonance imaging subsequently demonstrated suspicious bilateral inguinal lymphadenopathy. Following multidisciplinary counselling, the patient underwent bilateral radical vulvectomy with bilateral inguinal and femoral lymph-node dissection. Histopathology revealed malignant melanoma with a Breslow thickness of 2 mm and Clark level IV invasion; the lesion was non-ulcerated and margins were free of tumour. Immunohistochemistry was positive for HMB-45 and S100. The reported final pathological stage was pT2aN3aMx. The postoperative course was complicated by wound dehiscence, followed by acute pulmonary embolism and death despite resuscitative measures. The case highlights the diagnostic difficulty of vulvar melanoma, the prognostic importance of tumour thickness and nodal disease, and the need to integrate oncological treatment with meticulous postoperative venous-thromboembolism prevention and surveillance.