1012P - A multi-institutional dose-finding and efficacy confirmation trial of superselective intra-arterial infusion of cisplatin and concomitant radiotherapy for patients with locally advanced maxillary sinus cancer (JCOG1212, RADPLAT-MSC): Results of dose-finding phase

Abstract

Superselective intra-arterial infusion of high-dose cisplatin with concomitant radiotherapy (RADPLAT) has been performed for the patients with locally advanced maxillary sinus squamous cell carcinomas (LA-MSSCCs) in several institutions and has been reported to result in a favorable survival. This multi-institutional prospective trial was aimed to confirm the adequate dose and efficacy of RADPLAT for the patients with LA-MSSCCs. The dose-finding phase was performed to evaluate the incidence of dose-limiting toxicity (DLT) and to determine the recommended cycle of intra-arterial infusion of cisplatin. Eighteen patients were registered from 7 institutions for this study. In this dose-finding study, 100 mg/m2 of cisplatin was administered intra-arterially weekly for 7 weeks with concomitant radiotherapy (total 70 Gy). Cisplatin was skipped in the case of adverse events that met the skipping rule defined by the protocol. The recommended number of cycles was determined according to the distribution of the number of cycles of administered cisplatin and the incidence of DLT. The median age of all participants was 64 years old (range, 40-75 years old). Sixteen patients were diagnosed as T4aN0M0, and two patients as T4bN0M0. All patients achieved full dose of radiotherapy. The number of cycles of administered cisplatin was 7 in 13 patients and 6 in 5. DLT was observed in 5 patients; Gr 3 liver dysfunction (1), Gr 4 thrombocytopenia (1), Ccr < 40 (1), Gr 3 retinopathy (1), and Gr 3 retinal detachment (1). There was not either treatment-related death or neural complication. RADPLAT appears to be safe and well-tolerated at 7 cycles of cisplatin at a dose of 100 mg/m2 each cycle, which were determined to be the recommended number of cycles for LA-MSSCC.