Fenretinide (4-HPR) in chemoprevention of oral leukoplakia.

A controlled clinical trial has been underway at the Istituto Nazionale Tumori (INT) of Milan since 1988. The goal of the trial is to evaluate the effectiveness of fenretinide (4-HPR) in preventing relapses, new localizations, and carcinomas in patients with benign postoperative diagnoses who have been surgically treated for oral leukoplakias. This paper presents the design and the preliminary results of this study. To date, 137 patients have been randomized, following surgical excision of oral leukoplakia, to receive either 200 mg 4-HPR daily for 52 weeks or no intervention. Twenty local relapses or new localizations have occurred so far in the control group and 9 in the 4-HPR group. Seven patients have interrupted the intervention because of toxicity. No impaired dark adaptation has been observed. We conclude that 4-HPR is well-tolerated and appears to be effective in preventing relapses and new localizations during the treatment period.