Efficacy of vitamin A in the prevention of loco-regional recurrence and second primaries in head and neck cancer

Chemoprevention with retinoids is currently an experimental approach to prevent local relapses and second primaries in treated head and neck cancer patients. We evaluated the effectiveness of vitamin A in preventing the above events in a randomised trial involving 106 head and neck cancer patients who had achieved complete regression of their disease with radiotherapy and/or surgery. They were randomised to receive retinyl palmitate (200,000 IU per week for 1 year) or placebo. 50 subjects on vitamin A and 43 on placebo completed 1 year supplementation; 49 in the former group and 42 in the latter could be evaluated over a 3 year period from the initiation of the study. One fifth ($\text{11}\text{56}$) of patients in the vitamin A group and one tenth ($\text{5}\text{50}$) in the placebo group had loco-regional recurrence. The frequency of recurrences in stage I patients in the vitamin A group was higher compared to the placebo group, although it was not statistically significant. No second primaries were observed in the vitamin A group; 2 patients in the placebo group had second primaries. No clinically obvious side effects were observed with vitamin A. The higher frequency of recurrences in the vitamin A group is of concern although it may be a chance finding given the small size of the trial. The effect on second primaries is consistent with other observations reported in literature.