The use of cis-retinoic acid in recurrent respiratory papillomatosis of the larynx: a randomized pilot study.

We undertook a study of 13-cis-retinoic acid to evaluate its use as an adjuvant to laser surgery in the management of recurrent respiratory papillomatosis. In a double-blind study using placebo, four of the six subjects treated with this agent experienced recurrence while receiving therapy, with two requiring further surgical intervention. All six experienced toxicity, necessitating the withdrawal from therapy of two and dose reduction in three. When it became apparent that the therapy was ineffective, and caused toxicity, the study was closed.