Drug-Related Pneumonitis in Patients With Advanced Renal Cell Carcinoma Treated With Temsirolimus

Purpose Pneumonitis has occurred in patients treated with inhibitors of the mammalian target of rapamycin (mTOR). In a phase III study of patients with previously untreated, poor-prognosis, advanced renal cell carcinoma (ARCC), the mTOR inhibitor temsirolimus improved survival compared with interferon. We performed a retrospective, independent, blinded radiographic review of chest computed tomography (CT) images of patients in this study to characterize temsirolimus-related pneumonitis. Patients and Methods Patients were treated with intravenous temsirolimus 25 mg once weekly or subcutaneous interferon alfa 3 million units, with an increase to 18 million units, thrice weekly. Drug-related pneumonitis was identified based on sequential chest CT images, required every 8 weeks, showing changes consistent with pneumonitis and not pneumonia (infection) or disease progression as correlated with clinical data. Cumulative probability of drug-related pneumonitis was estimated using the Kaplan-Meier method.