Capecitabine to reduce nonmelanoma skin carcinoma burden in solid organ transplant recipients

Background Solidorgan transplant recipients (SOTRs) are at greater risk of nonmelanoma skin cancer (NMSC) than the general population, in large part because of their immunosuppression. Select individual SOTRs demonstrate a rate of tumor development at the upper end of their cohort. Capecitabine, a prodrug converted in the body to 5-fluorouracil (5-FU), may alter the risk for development of NMSC in an individual SOTR with a high rate of tumor development. Objective To report observations of a series of 10 SOTRs treated with capecitabine as adjuvant prevention for high-incidence NMSC. Methods Ten SOTRs were administered cycles of low-dose oral capecitabine (0.5-1.5 g/m² per day) for days 1 to 14 of a 21-day treatment cycle. Measurements (skin screenings, laboratory and toxicity monitoring) were performed every 1 to 3 months. Incidence rates of squamous cell carcinoma (SCC) before and during treatment were determined and compared using the Wilcoxon signed-rank test. Results The average incidence rate (mean ± SD) of SCC before treatment (0.56 ± 0.28 SCCs/month, range 0.17-1.17 SCCs/month) declined to 0.16 ± 0.11 SCCs/month (range 0-0.33 SCCs/month) during the first 12 months of treatment (mean reduction 68 ± 30.0%, range 0-100%, p <.005). Reduction in actinic keratosis was observed. Common side effects included fatigue, nausea, hand-and-foot syndrome, gout, and poor renal function. Seven of 10 participants required dose adjustment, and two of these were discontinued from the study drug because of side effects. Limitations Case series design, small observational population. Conclusions SOTRs experienced a clinically and statistically significant decline in incident SCCs during treatment with low-dose oral capecitabine, with varying degrees of side effects. Larger randomized trials will determine the dose and efficacy of capecitabine for adjuvant treatment of NMSC in SOTRs.