Hazards of topical mitotic blocking agents.

Abstract

To the Editor.— With regard to the correspondence between Gaylarde and Sarkany and Kligman (112:556, 1976) as to the advisability of using colchicine ointment in psoriasis, the article by Belisario 1 is relevant. He cites five cases of severe hematopoietic depression leading to death in three, and one death associated with internal toxicity in patients treated topically with demecolcine (Colcemid [Britain]) ointment for skin cancers. Demecolcine is N -desacetyl methylcolchicine. Both demecolcine and colchicine are derived from the meadow saffron plant and block mitoses in metaphase. Demecolcine was reported to be 30 times less toxic than colchicine. The cytotoxic effects of podophyllin, another mitotic blocking agent, and colchicine are similar. 2 One death has resulted from the topical use of podophyllin for condyloma acuminata of the vulva. 3 While I agree with Kligman that one must take risks to alleviate the agony of psoriasis, it would appear that the hazards