Fig. 2

Macroscopic and microscopic images of a 73-year-old woman with vulvar melanoma. a External appearance before boron neutron capture therapy (BNCT): a black macula (arrows) on her vulva was asymmetrical in shape and variable in color. b Microscopic findings: the dermis showed a massive infiltrate of tumor cells. The cells had large hyperchromatic and irregularly shaped nuclei with multiple mitoses (upper). A small number of pigment cells were seen. Tumor cells were positive for HMB-45 (lower) and S-100. c External appearance after BNCT: the absorbed doses were 8.0 Gy-Eq to the normal vaginal mucosa and 29 Gy-Eq to the melanoma. The black macule slowly faded and was no longer visible 4 months later. No severe adverse local side effects such as ulceration nor local recurrence were seen at the site of irradiation. However, she died of disseminated metastatic disease 1.1 years later