Objective: To identify and compare treatment and system factors associated with survival in early-stage glottic cancer.
Study design: Retrospective study of cases in the Commission on Cancer National Cancer Database.
Methods: Adult patients with early glottic cancer (stage I or II) diagnosed between January 1, 2004, and December 31, 2012, were included. Demographic, tumor, and survival variables were included in the analyses. Multivariate Cox regressions as well as univariate Kaplan-Meier analyses were conducted.
Results: In total, 5,627 patients were included in the study. Treatment factors associated with improved survival included larynx-preserving surgery alone (hazard ratio [HR] 0.740; P = 0.001) and larynx-preserving surgery with radiation (HR 0.837; P = 0.010) when compared to radiotherapy alone. System factors associated with worse survival included intermediate- (HR 1.123; P = 0.047) or low- (HR 1.458; P = 0.017) volume centers; Medicaid (HR 1.882; P < 0.001), Medicare (HR 1.532; P < 0.001), or other government insurance (HR 2.041; P < 0.001); and delay between diagnosis and treatment greater than 100 days (HR 1.605; P = 0.006).
Conclusion: A number of treatment and system factors were found to be significantly associated with survival when controlling for patient and tumor factors. These may present targets for the improvement of outcomes in early-stage glottic cancers.
Level of evidence: 4. Laryngoscope, 127:616-622, 2017.
Keywords: Glottic cancer; NCDB; facility case volume; survival; treatment delay.
© 2016 The American Laryngological, Rhinological and Otological Society, Inc.