The primary outcome was the number of
keratinocyte carcinomas overall and, specifically, the number of squamous cell carcinomas (SCCs) before and after the switch.
The interim finding of an unexpected rise in lung cancer incidence and all-cause mortality prompted the premature halt of the Department of Veterans Affairs Topical Tretinoin Chemoprevention (VATTC) trial, a large 6-year study designed to determine whether the treatment could prevent basal and squamous cell skin cancers in patients who already had at least two such
keratinocyte carcinomas. Increased lung cancer incidence and mortality had previously been reported with systemically administered compounds closely related to tretinoin.
Those results suggested development of these
keratinocyte carcinomas in immunocompetent patients may be driven in part by HPV, the investigators said at the time.
SAN FRANCISCO -- Patients with high-risk
keratinocyte carcinomas sometimes present with neurologic symptoms mimicking Bell's palsy or trigeminal neuralgia, making the diagnosis of these perineural tumors challenging, Siegrid Yu, MD, said at the annual meeting of the Pacific Dermatologic Association.
Participants averaged 71.5 years of age (standard deviation, 0.57 years), 97% were male, 99% were white, and all had clinically meaningful histories of sun damage with at least two
keratinocyte carcinomas in the previous 2 years, including at least one lesion on the face or ears.
