A multicenter retrospective analysis of patients with nasopharyngeal carcinoma treated in IMRT era from a nonendemic population: Turkish Society for Radiation Oncology Head and Neck Cancer Group Study (TROD 01-001)

Background: We aimed to evaluate patients with nasopharyngeal carcinoma (NPC) in a nonendemic population. Methods: In a national, retrospective, multicenteric study, 563 patients treated with intensity modulated radiotherapy at 22 centers between 2015 and 2020 were analyzed. Results: Median age was 48 (9–83), age distribution was bimodal, 74.1% were male, and 78.7% were stage III-IVA. Keratinizing and undifferentiated carcinoma rates were 3.9% and 81.2%. Patients were treated with concomitant chemoradiotherapy (48.9%), or radiotherapy combined with induction chemotherapy (25%) or adjuvant chemotherapy (19.5%). After 34 (6–78) months follow-up, 8.2% locoregional and 8% distant relapse were observed. Three-year overall survival was 89.5% and was lower in patients with age ≥50, male sex, keratinizing histology, T4, N3 and advanced stage (III-IVA). Conclusions: Patients with NPC in Turkey have mixed clinical features of both east and west. Survival outcomes are comparable to other reported series; however, the rate of distant metastases seems to be lower.