Association of Preoperative Functional Performance with Outcomes after Surgical Treatment of Head and Neck Cancer: A Clinical Severity Staging System

Importance: Patients with head and neck cancers have comorbidities and other constitutional symptoms known to be associated with adverse postoperative outcomes, but the role of functional performance is not well studied. Objective: To explore the addition of functional performance to other clinical factors for association with 3 patient outcomes: 30-day unplanned readmission (UR), 90-day medical complications, and overall survival (OS). Design, Setting, and Participants: This retrospective cohort study was conducted in a single tertiary care center with patients surgically treated for squamous cell cancer of the lip, oral cavity, pharynx, or larynx from January 2012 to December 2016. All analysis took place between January 2018 and November 2018. Data from 2 registries were analyzed, supplemented with medical record review. Logistic regression analysis was used to explore association of preoperative functional performance with outcomes. Conjunctive consolidation was used to create a useful clinical severity staging system, which included functional performance (estimated from metabolic equivalent [MET] score: <4, light-intensity activities; ≥4 at least moderate-intensity activities); overall comorbidity severity; preoperative weight loss; and TNM tumor staging. Logistic regression was used to assess the prognostic accuracy of the clinical severity staging system for 30-day UR and 90-day complications, and Cox proportional hazard regression for OS. Exposures: All patients underwent surgical treatment for head and neck cancer. Main Outcomes and Measures: The primary outcomes were 30-day UR and 90-day complications; the secondary outcome was OS. Results: For the 657 patients included, the mean (SD) age was 62.0 (11.3) years; 73% were men (n = 477), and 88% were white (n = 580). A total of 75 (11%) had a 30-day UR; 204 (31%) developed a 90-day complication; and 127 (19%) patients died during the observation period. Individually, poor functional performance (<4 METs), high comorbidity burden, preoperative weight loss, and advanced TNM stage were associated with all 3 outcomes; the increased risk for each outcome ranged from 1.5 to 3.0 times the reference range. Using these 4 variables in combination, the 4-category clinical severity staging system demonstrated a strong association between severity stage and all 3 adverse outcomes: 30-day UR (C statistic, 0.63), 90-day complications (C statistic, 0.63), and OS (C statistic, 0.68). Conclusions and Relevance: Poor preoperative functional performance, high comorbidity burden, preoperative weight loss, and advanced tumor stage were all associated with worse patient outcomes after head and neck cancer surgery. The model incorporating all 4 of these factors developed in this study may facilitate patient-centered risk assessment and patient-physician shared preoperative decision making.