Primary intestinal-type adenocarcinoma of the vulva with high tumor mutational burden and cancer-associated mutations: a case report

Abstract

Abstract Background Vulvar cancer is a rare disease, accounting for about 5% of gynecological malignancies. Intestinal-type adenocarcinoma of the vulva is extremely rare, and details regarding its origin and related genetic mutations are unknown. Treatment options for this cancer have not been defined. Case presentation A 63-year-old Japanese woman came to the hospital because she was aware of a vulvar mass. There was a 1 cm mass on the dorsal side of the vulva, just outside the remains of the hymen. Biopsy revealed suspected adenocarcinoma, and wide local excision was performed. Based on histopathology and immunohistochemistry, the mass was diagnosed as intestinal-type adenocarcinoma. No other primary lesions were found, and the vulva was considered the primary site. The Gene panel test (FoundationOneCDx assay) showed a high tumor mutational burden and gene mutations in TP53, KEL, RB1, RNF43, PTEN, GNAS, and PIK3CA. ConclusionsIn cases of intestinal-type adenocarcinoma of the vulva, it may be helpful to check tumor mutational burden and gene mutations for treatment selection.