Prognostic Value of Impaired Vocal Cord Mobility in T2N0 Glottic Cancer Treated With IMRT

To evaluate the prognostic importance of impaired vocal cord mobility (VCM) in T2N0 glottic cancer.

All patients with T2N0 glottic cancer treated with partial laryngeal IMRT in 2009-2021 in our institution were retrospectively reviewed. For comparison, cohorts with T1N0 and T3N0 disease were also included. Locoregional failure (LRF), disease-free survival (DFS), and overall survival (OS) were compared among T1N0, T2N0 with normal VCM (T2-Normal-VCM), T2N0 with impaired VCM (T2-Impaired-VCM), and T3N0 groups. Multivariable analysis (MVA) assessed the prognostic value of VCM within the T2N0 group.

A total of 642 cases were included: 288 T1N0, 224 T2N0 (147 T2-Normal-VCM, 77 T2-Impaired-VCM), and 130 T3N0. Median follow-up was 5.0 years (IQR 3.4-6.2). Five-year LRF for T1N0, T2-Normal-VCM, T2-Impaired-VCM, and T3N0 were 4% (95% CI 2-6), 9% (5-15), 27% (17-38), and 35% (27-44), respectively. Corresponding DFS was 83% (78-88), 80% (73-87), 55% (45-68), and 50% (41-60), while OS was 85% (80-90), 86% (80-92), 71% (61-83), and 59% (50-69), respectively. In T2N0, MVA confirmed that impaired VCM was associated with higher LRF (aHR 3.72 [95% CI 1.79-7.71], p < 0.001), lower DFS (aHR 2.74 [1.68-4.45], p < 0.001), and lower OS (aHR 2.07 [1.17-3.67], p = 0.013).

In this contemporary cohort, LRF rates increased stepwise from T1N0 to T2-Normal-VCM, T2-Impaired-VCM, and T3N0 glottic cancer. Within T2N0 disease, impaired VCM is an adverse prognostic factor, supporting subdivision into T2a (normal VCM) and T2b (impaired VCM) in future TNM revisions. Prospective studies are warranted to assess whether treatment intensification can improve outcomes for T2-Impaired-VCM disease.