Increased pathologic upstaging with rising time to treatment initiation for head and neck cancer: A mechanism for increased mortality

Abstract

Background: Time to treatment initiation (TTI) is increasing and is associated with worsening survival. In the current study, the authors sought to identify a mechanism for this relationship by assessing the effect of TTI on clinical-to-pathologic upstaging in patients with head and neck squamous cell carcinoma (HNSCC).

Methods: Using the National Cancer Data Base, the authors analyzed patients receiving definitive surgery for SCC of the oral cavity, oropharynx, larynx, and hypopharynx from 2005 through 2014. The primary outcome was T, N, or stage group upstaging, defined as higher pathologic stage than clinical stage. TTI was defined as the time between diagnosis and surgery. Multivariable logistic and Cox proportional hazards regression modeled upstaging and survival, respectively.

Results: Cohorts of 60,194 patients, 51,380 patients, and 52,980 patients, respectively, with complete T, N, and stage group data were included. N upstaging was most common (18.6%), followed by stage group (17.4%) and T (12.1%) upstaging; all types were predicted by TTI. Compared with a TTI of 1 to 6 days, TTIs as short as 7 to 13 days (odds ratio, 1.20; P = .038) or ≥ 70 days (odds ratio, 2.04; P < .001) were found to predict T upstaging, a finding that is consistent for N and stage group upstaging. Using restricted cubic splines, relative odds of T and stage group upstaging escalated to 2.25 and 1.93, respectively, at a TTI of 365 days. In survival analyses, T (hazard ratio [HR], 1.53), N (HR, 1.88), and stage group (HR, 1.69) upstaging all predicted mortality (P < .001), whereas TTI only predicted mortality after 70 days (HR, 1.11; P = .023).

Conclusions: Tumor progression, measured by clinical-to-pathologic upstaging, increases mortality for patients with HNSCC experiencing treatment delays. Cancer 2018;124:1400-14. © 2018 American Cancer Society.

Keywords: National Cancer Data Base; head and neck squamous cell carcinoma; overall survival; time to treatment initiation; upstaging.