The Impact of Demographic and Clinico-Pathological Characteristics on Recurrence-Free Survival in Nasopharyngeal...

Nasopharyngeal carcinoma (NPC) is an uncommon malignancy with a distinct geographical distribution. However, data from non-endemic areas are limited. This study aims to evaluate oncological outcomes and identify prognostic factors in a large cohort of non-metastatic NPC patients treated at a tertiary center in Israel.

This single-institution, retrospective study included 181 patients diagnosed with non-metastatic NPC and treated with radiotherapy between 2005 and 2022. Data were collected from electronic medical records and included demographics, disease characteristics, treatment details, and outcomes. Recurrence-free survival (RFS) and overall survival (OS) were estimated using Kaplan-Meier analysis. Cox proportional hazards models were used to assess prognostic factors.

The median follow-up was 57 months. The cohort was predominantly male (82%), with a mean age of 51.7 years. Most patients had non-keratinizing histology, 75%presented with stage III-IV disease, and 86% received concurrent chemoradiotherapy. Induction chemotherapy was administered to 71%, though only 6.5% received the full three-cycle regimen. Nearly 90% were treated using modern radiotherapy techniques (VMAT), and 75% received concurrent chemotherapy. The 3-year RFS and OS were 82.6% and 91.2%, respectively; the 5-year RFS and OS were 77.7% and 84.7%. Age threshold analysis demonstrated that younger age predicted improved RFS (HR range, 3-5; p < 0.05). In the multivariate analysis, patients aged > 50 years had a significantly higher risk of recurrence (HR 6.02, 95% CI 1.30-27.85), while stage IV disease showed a borderline association with poorer RFS (HR 2.81, 95% CI 0.96-8.27), reaching statistical significance in the 30-50 years age group (HR = 7.06, 95% CI 1.14-43.76, p = 0.036). Smoking demonstrated a non-significant trend toward increased recurrence risk (HR 1.61, 95% CI 0.85-3.04). Similar patterns were seen for OS, with age >50 showing elevated but non-significant risk (HR 3.43, 95% CI 0.73-16.06), partly due to limited events. Bedouin ethnicity was associated with higher prevalence and a significantly younger age at diagnosis (39.4 ± 16.0 vs. 52.7 ± 16.9 years, p = 0.004), with a non-significantly better outcome.

In this non-endemic cohort, favorable oncologic outcomes were observed. The age at diagnosis is a key prognostic factor. The higher incidence, younger age and better outcomes among the Bedouin ethnicity warrant further investigation calling for improved risk stratification and personalized treatment strategies.