Risks of BCG intralesional therapy: an experience with melanoma.

A nearly fatal allergic reaction to intratumor BCG injections was associated with a complete remission of recurrent malignant melanoma. Clinical course and histologic sections suggested both anaphylactic and Arthus reactions. The occurrence of reactions at BCG injection sites as well as at uninjected sites of tumor suggests common BCG and melanoma antigens. The management of events involved in this often fatal postimmunotherapy complication involves the early administration of parenteral fluids, antituberculous therapy, antihistamines, and possible steroids. The prophylactic use of antihistamines and an in-hospital administration of intralesional BCG immunotherapy are strongly suggested. In the future, prophylactic INH may prove to be both therapeutically efficacious and protective against infectious complications.