Oral prednisone use and risk of keratinocyte carcinoma in non-transplant population. The VATTC trial

Background Glucorticosteroids (GC) are potent anti-inflammatory medications with immunosuppressive property. Few retrospective studies have reported the increased risk of development of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) associated with GC use. Objective We aimed to assess the effect of oral GC use on the risk of BCC and SCC using prospective data. Methods We analysed data from the Veterans Affairs Topical Tretinoin Chemoprevention Trial, which followed up patients from 1998 to 2004. Exposure to oral GCs was defined as (1) use of any oral GCs at any point during follow-up and (2) use of GCs for a month or longer. Outcome was occurrence of new BCC or SCC. Cox proportional hazard models were used to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Results Among the 1051 study participants, 148 patients (14%) had prednisone prescription filled during study period, and 63 (6%) used prednisone for over a month. A total of 472 patients (45%) developed at least one BCC during study: 394 (44%) among non-users of prednisone and 78 (53%) among any time users. The total number of new SCC was 309 (29%): 258 (29%) among non-users of prednisone and 51 (34%) among users. Among any time prednisone users, the adjusted HR was 1.11 (95% CI, 0.871.42) for BCC, and 1.05 (95% CI, 0.761.45) for SCC. Among those who used prednisone for 30 or more days, the HR was 1.26 (95% CI, 0.901.78) for BCC, and 1.03 (95% CI, 0.661.60) for SCC. Conclusion This study does not support the existence of association between use of oral GCs and risk of BCC or SCC.