Prognostic Significance of Radiologic Extranodal Extension in Nasopharyngeal Cancer

Objective. The aim of the present study was to evaluate the prognostic value of radiologic extranodal extension (rENE) in patients with nasopharyngeal cancer. Study Design. Retrospective review. Setting. Tertiary university hospital. Methods. We identified patients with nasopharyngeal cancer and lymph node metastasis who underwent pretreatment neck computed tomography or magnetic resonance imaging and evaluated rENE from the involved lymph node. Univariate Kaplan-Meier and multivariate Cox regression analyses were used to compare rENE1 and rENE- groups for local regional relapse-free survival, distant metastasis-free survival, and overall survival. Results. Of 61 cases, 24 (39.3%) were rENE1 and 37 (60.7%) were rENE-. The median follow-up was 65.5 months. The 5-year distant metastasis-free survival and overall survival rates were lower in the rENE1 group than the rENE- group (70.8% vs 89.2%, P =.016; 66.7% vs 89.2%, P =.01, respectively). Differences in locoregional control between the groups were not significant (P =.18). The 5-year rates for local regional relapse-free survival were 87.5% for rENE1 and 91.9% for rENE-. In multivariate analysis, the presence of rENE was a significant independent adverse prognostic factor for distant metastasis-free survival and overall survival. Conclusions. We showed that rENE is an independent prognostic factor for poor distant control and survival in patients with nasopharyngeal cancer.