Radiation with concomitant superselective intra-arterial cisplatin infusion for maxillary sinus squamous cell carcinoma Abstract Purpose To assess the efficacy and prognostic factors after superselective intra-arterial chemoradiation (RADPLAT) for maxillary sinus squamous cell carcinoma (MS-SCC). Materials and methods Prognostic significance of age, gender, T and N factors, gross tumor volume of the primary-site (GTV), total cisplatin dosage, and total cisplatin dosage per GTV (CDDP/GTV) for primary-site recurrence-free survival rate (PRFS) were analyzed. RADPLAT was administered to 27 patients. The median follow-up period was 42.1 months. Results The 3-year rates of overall survival and PRFS were 59.2% and 53.9%, respectively. In univariate analysis, age, male, and total cisplatin dosage were significant factors for PRFS. In multivariate analysis, lymph node metastasis was significant factors for PRFS, and gender and total cisplatin dosage weakly influenced PRFS. In acute phase, no patient showed ≥ grade 3 hematologic toxicity, and grade 3 mucositis developed in 5 patients. Late toxicities were recognized in 3 patients (grade 2 phlegmon of the face, grade 3 maxillofacial osteonecrosis, and retinopathy). Twelve patients (44%) experienced recurrences. Of them, 8 patients showed recurrence at the primarysite. Conclusion RADPLAT was effective for MS-SCC, with acceptable toxicity. Total cisplatin dosage is suggested to be important for primary tumor control.