Refining the Role of Lymph Node Biopsy in Survival for Patients with Nasopharyngeal Carcinoma: Population-Based Study from the Surveillance Epidemiology and End-Results Registry.

Abstract

The updated version of the National Comprehensive Cancer Network (NCCN) guidelines revised pretreatment workup for nasopharyngeal carcinoma (NPC) into "biopsy of the primary site or neck." Despite provision of important diagnostic information, concerns regarding tumor cell dissemination limit the application of lymph node biopsy. This study aimed to investigate whether biopsy of the neck is associated with impaired survival in NPC. A propensity score-matched, population-based cohort identified from the Surveillance, Epidemiology, and End Results database was used to compare overall survival (OS) and disease-specific survival (DSS) of patients who underwent pretreatment cervical lymph node biopsy without subsequent neck dissection or removal of node compared with patients who did not undergo node biopsy. Of 2910 eligible patients, 416 (14.3%) underwent pretreatment lymph node biopsy. After use of control for patient, tumor, and demographic characteristics, biopsy was not associated with impaired OS (hazard ratio [HR], 1.15; 95% confidence interval [CI] 0.89-1.47; P=0.29) or DSS (HR, 1.07; 95% CI 0.81-1.40; P=0.63). Interestingly, in the subgroup analysis, the unfavorable effect of biopsy was observed for patients with differentiated non-keratinizing squamous cell carcinoma (but not other histologic types). Race did not positively alter the survival outcomes. The findings provide reference for clinical practice, showing that pretreatment cervical lymph node biopsy is not associated with impaired survival in NPC, except for patients with differentiated non-keratinizing squamous cell carcinoma. The recommended NCCN guidelines would be more specific by adding details to the general recommendation that neck biopsy is safe for all patients. Future prospective studies are needed to verify the study findings.