Treatment of cutaneous neoplasia with etretinate in renal transplant recipients.

Six patients who had developed neoplastic and pre-neoplastic cutaneous lesions following a successful renal transplant were treated with etretinate, 1 mg/kg/day, for six months. In four cases there was almost complete resolution of the lesions; one patient had only a partial response, and one patient developed further lesions whilst on treatment. Patients were observed for six months after treatment was discontinued. Two patients in the group that had responded well to treatment developed further lesions. No deterioration in renal function, as measured by serial serum creatinine concentrations and creatinine clearance, occurred in any of the patients treated. In-vivo measures of the cutaneous cell-mediated immune response were unaltered, but cell kinetic studies demonstrated an increase in proliferative activity in sun-exposed skin during treatment, suggesting that the anti-tumour effect of etretinate is not due to a cytostatic action, and does not require an intact immune system. On the basis of our observations, we feel that further studies are warranted with larger numbers of patients.