Predictors of basal cell carcinoma in high-risk patients in the VATTC (VA Topical Tretinoin Chemoprevention) trial

Basal cell carcinoma (BCC) is the most common cancer in the United States today, and patients who have had one are likely to have multiple carcinomas over time. Predictors of new BCCs on the face and ears among those at very high risk have not been studied in detail. We sought to do so prospectively in the context of a 6-year trial. We found that the number of BCCs in the prior 5 years was the most important predictor. Age, sun sensitivity, occupational sun exposure before the age of 30 years (but not afterward), lower educational level, history of eczema, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, and more sunscreen use in the week, but not the 6 months, before enrollment were also independent predictors, but sunburns, baseline sun exposure, and other sun-protective measures, other skin cancers, and actinic keratoses were not. None of the eczema patients had a history of topical calcineurin use. The cumulative risk of BCC was 55% at 5 years. These findings document the key risk factors in this very high-risk population, suggesting that the history of eczema may increase the risk in those at high risk and that early sun exposure is important even in this group, and underscoring the need for chemopreventive strategies.