Complete remission of metastatic malignant melanoma following immunotherapy with Bacillus Calmette-Guerin (BCG): report of a case.

A complete response to BCG is described in a case of recurrent melanoma. In a woman aged 38 years, intracutaneous metastatic deposits confined to the limb of origin had occurred after excision of a malignant melanoma from the ankle, and elective groin dissection had shown two lymph nodes infiltrated with melanoma. BCG vaccine was applied to the buttock, initially by scarification and later by a multiple puncture gun. All metastases slowly regressed, and biopsy of a metastatic site at six months showed no tumour cells. The patient remains free of detectable disease 36 months after the commencement of therapy. It is inferred that BCG may facilitate remission of melanoma, perhaps by reason of antigenic cross-reactivity between BCG and surface components of human melanoma cells.