Association of Pharyngocutaneous Fistula With Cancer Outcomes in Patients After Laryngectomy: A Multicenter Collaborative Cohort Study.

Importance: Pharyngocutaneous fistula (PCF) results in an inflammatory reaction, but its association with the rate of locoregional and distant control, disease-free survival, and overall survival in laryngeal cancer remains uncertain. Objective: To determine if pharyngocutaneous fistula after salvage laryngectomy is associated with locoregional and distant control, disease-free survival, and/or overall survival. Design, Setting, and Participants: A multicenter collaborative retrospective cohort study conducted at 5 centers in Canada and the US of 550 patients who underwent salvage laryngectomy for recurrent laryngeal cancer from January 1, 2000, to December 31, 2014. The median follow-up time was 5.7 years (range, 0-18 years). Main Outcomes and Measures: Outcomes examined included locoregional and distant control, disease-free survival, and overall survival. Fine and Gray competing risk regression and Cox-proportional hazard regression models were used for outcomes. Competing risks and the Kaplan-Meier methods were used to estimate outcomes at 3 years and 5 years. Results: In all, 550 patients (mean [SD] age, 64 [10.4] years; men, 465 [85%]) met inclusion criteria. Pharyngocutaneous fistula occurred in 127 patients (23%). The difference in locoregional control between the group of patients with PCF (75%) and the non-PCF (72%) group was 3% (95% CI, -6% to 12%). The difference in overall survival between the group with PCF (44%) and the non-PCF group (52%) was 8% (95% CI, -2% to 20%). The difference in disease-free survival between PCF and non-PCF groups was 6% (95% CI, -4% to 16%). In the multivariable model, patients with PCF were at a 2-fold higher rate of distant metastases (hazard ratio, 2.00; 95% CI, 1.22 to 3.27). Distant control was reduced in those with PCF, a 13% (95% CI, 3% to 21%) difference in 5-year distant control. Conclusions and Relevance: This multicenter retrospective cohort study found that development of PCF after salvage laryngectomy is associated with an increased risk for the development of distant metastases.