Prognostic impact of matted lymphadenopathy in patients with oropharyngeal squamous cell carcinoma treated with definitive chemoradiotherapy

Abstract

ObjectiveTo determine whether cervical matted lymphadenopathy (ML) is associated with outcomes in patients with oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive chemoradiotherapy (CRT). Materials and MethodsOPSCC patients treated at our institution with CRT were included (n = 417). ML was defined by three adjacent nodes without an intervening fat plane. Patients were stratified into favorable OPSCC (p16 + with ≤ 10 pack-years smoking history) or unfavorable OPSCC (p16- and/or > 10 pack years). Primary outcomes were overall survival (OS) and progression-free survival (PFS) and the cumulative incidences of regional recurrence (RR) and distant metastasis (DM). ResultsThe median follow-up time for the surviving cohort was 49.9 months. In favorable OPSCC (n = 220), there were no significant associations between ML and any outcome. In unfavorable OPSCC (n = 197), ML had a significant negative impact on OS and PFS, with 3-year OS for patients without and with matted nodes at 74% and 56% (HR, 1.61, 95% CI 1.01–2.58). On multivariable Cox regression, patients with ML experienced significantly worsened OS (HR 1.65, 95% CI 1.03–2.65) and PFS (HR 1.94, 95% CI 1.28–2.93). The cumulative incidence of DM was also higher with ML (31% vs. 9%, adjusted HR 3.3, 95% CI 1.71–6.48). ConclusionML carries no prognostic importance in patients with favorable OPSCC. However, ML portends significantly worse outcomes in individuals with HPV-negative disease or a significant smoking history. Thus, ML may help risk-stratify this latter population for treatment intensification, but does not seem to be a contraindication for treatment de-escalation in the former.