To analyze the prognostic value of lymph node ratio (LNR, number of metastatic nodes divided by total nodes excised) and to determine whether LNR can guide treatment decisions in human papillomavirus (HPV)-related oropharyngeal carcinoma (OPC). We retrospectively included HPV-related OPC who underwent surgery and lymph node dissection between 2010 and 2020 using the data from the Surveillance, Epidemiology, and End Results program. Receiver operating characteristic (ROC) curve, Kaplan-Meier analysis, and Multivariate Cox regression models were used for statistical analyses. A total of 2922 patients were included. The ROC curve analysis showed that LNR has significantly better efficacy than pathological nodal (pN) staging in predicting overall survival (OS) in patients without adjuvant radiotherapy (area under the curve 0.726 vs. 0.681, P = 0.047). Using OS as the endpoint, the optimal cutoff values for predicting OS were determined by ROC curve analysis to be 4.0% for LNR. Multivariate analysis confirmed LNR ≥ 4.0% as an independent prognostic factor for worse cancer-specific survival (CSS) and OS in the entire cohort and in those without adjuvant radiotherapy. In the subgroup with LNR < 4.0%, there was no significant difference in CSS (P = 0.788) and OS (P = 0.327) between patients who received radiotherapy and those who did not. However, in the group with LNR ≥ 4.0%, radiotherapy resulted in better 3-year CSS (95.2% vs. 85.9%, P < 0.001) and OS (93.9% vs. 82.7%, P < 0.001) than those who did not. LNR-based stratification could potentially spare 24.4% of patients from unnecessary adjuvant radiotherapy. LNR is a significant prognostic factor in HPV-related OPC and can help refine risk stratification and treatment decision-making. Adjuvant radiotherapy provides substantial survival benefits in patients with LNR ≥ 4.0%. Not applicable.
Lu et al. (Thu,) studied this question.