Ristivojevic, Julija Jovanovic (59161571500)Julija Jovanovic (59161571500)RistivojevicKorda, Natasa Jovanovic (57761965300)Natasa Jovanovic (57761965300)KordaVujanac, Vukac (36132436600)Vukac (36132436600)VujanacNikitovic, Marina (6602665617)Marina (6602665617)NikitovicArsenijevic, Tatjana (6508074168)Tatjana (6508074168)Arsenijevic2025-07-022025-07-022025https://doi.org/10.3892/ol.2025.15029https://www.scopus.com/inward/record.uri?eid=2-s2.0-105003406590&doi=10.3892%2fol.2025.15029&partnerID=40&md5=9a1a7a4a0b3a66d0d1888b37f18254adhttps://remedy.med.bg.ac.rs/handle/123456789/11422Chemoradiotherapy (CRT) is considered the stan dard of care for non keratinizing nasopharyngeal carcinoma (NK NPC) worldwide, with improved overall survival, local recurrence free survival and distant metastasis free survival rates compared with radiotherapy alone. However, CRT is associated with late toxicities that can diminish a patient's quality of life and increase morbidity and mortality rates. Following the geographical distribution of NK NPC, research has predominantly been performed on the endemic Asian population of patients. To extrapolate these results, more inves tigations in non Asian populations are needed. The present study aimed to analyze the occurrence and severity of late toxicities following CRT strictly in patients with non endemic NK NPC. The clinical retrospective study included 36 patients >18 years of age with pathohistologically confirmed NK NPC who were treated in the Institute of Oncology and Radiology of Serbia (Begrade, Serbia) with CRT during a 5 year period (January 2015 to December 2020). After completing combined treatment with a mean tumor dose of 68.64Gy and a median of 4 cycles of weekly cisplatin (40 mg/m2), late sequelae were routinely assessed during regular follow ups and graded according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer ‘Late Radiation Morbidity Scoring Schema’. Overall late toxicities were registered in 83.3% of the patients, mostly at grade ≤2. Neck fibrosis was observed in 69.44% and xero stomia in 58.33% of patients. Late dysphagia was experienced by 2 patients, secondary hypothyroidism by 4 patients and neuropathy by 3 patients. In conclusion, based on the results of the present study, late toxicities can be expected in the majority of patients with non endemic NK NPC following CRT. However, late sequelae are of lower grade, with neck fibrosis and xerostomia being the most predominant. Copyright © 2025 Ristivojevic et al.combined treatmentlate sequelsnasopharyngeal cancer