Background: To identify the diagnosis and treatment strategies by analyzing the clinical characteristics and treatment methods of RNNCLR.
Methods: A total of 210 patients pathologically diagnosed with RNNCLR were retrospectively included. Clinical characteristics, MRI features, treatment methods, and survival outcomes were analyzed. Propensity score matching (PSM) analysis was performed to adjust the surgical benefit.
Results: Ninety-one patients (43.3%) took a single biopsy, 67 patients (31.9%) underwent repeated biopsies and 52 patients (24.8%) received endoscopic surgery to obtain pathological positive tissues. RNNCLR had characteristic imaging features distinguished from pure radiation necrosis. The interval from the previous radiotherapy was 13.2 (7.0, 23.3) months. The 1-year, 3-year, and 5-year overall survival rates were 59.6%, 32.3%, and 14.6%. Patients with reirradiation, detectable EBV-DNA level, or ICA exposure had a worse prognosis. Overall survival was significantly higher in the endoscopic surgery group than in nonsurgery group after PSM (3-year OS rates, 44.5% vs. 23.9%, p = 0.011).
Conclusions: Histopathological diagnosis of RNNCLR needs repeated biopsies or even surgery. Careful analysis of MRI images, correlation with interval time from last radiation, and short-term follow-up may solve the diagnostic dilemmas. Endoscopic surgery results in a survival benefit by completely resecting lesions or removing necrotic tissue to reduce necrosis-related complications.
Keywords: Nasopharyngeal carcinoma; endoscopic surgery; local neoplasm recurrences; necrosis; radiotherapy.