Assessment of Predictive Scoring System for 90-Day Mortality Among Patients With Locally Advanced Head and Neck Squamous Cell Carcinoma Who Have Completed Concurrent Chemoradiotherapy.

Importance: There is currently no system to predict 90-day morality among patients with locally advanced head and neck squamous cell carcinoma (HNSCC) after the completion of concurrent chemoradiotherapy (CCRT). Objective: To validate the accuracy of a predictive scoring system for 90-day mortality among patients with locally advanced HNSCC who have completed CCRT. Design, Setting, and Participants: This prognostic study included 16 029 patients with HNSCC who completed CCRT between January 2006 and December 2015. Data were extracted from the Taiwan Cancer Registry Database. A risk scoring system was developed based on significant risk factors and corresponding risk coefficients. Data analysis was conducted from June 2018 to February 2019. Exposures: Mortality within 90 days of completion of definitive CCRT. Main Outcomes and Measures: The 90-day mortality rate after completion of CCRT and the accuracy of the scoring system, based on a comparison of mortality rates between training and test data sets. Results: Among 16 029 patients with locally advanced HNSCC, 1068 (6.66%; 1016 [95.1%] men; mean [SD] age, 55.11 [11.45] years) died before reaching the 90-day threshold, and 14 961 (93.4%; 14 080 [94.1%] men; mean [SD] age, 52.07 [9.99] years) survived. Multivariable analysis revealed that being aged 50 years or older (adjusted hazard ratio [aHR], 1.263; 95% CI, 1.104-1.445; P < .001), being aged 70 years or older (aHR, 2.183; 95% CI, 1.801-2.645; P < .001), having pneumonia (aHR, 1.946; 95% CI, 1.636-2.314; P < .001), having sepsis (aHR, 3.005; 95% CI, 2.503-3.607; P < .001), having hemiplegia (aHR, 1.430; 95% CI, 1.085-1.884; P = .01), having moderate or severe renal disease (aHR, 2.054; 95% CI, 1.643-2.568; P < .001), having leukemia (aHR, 4.541; 95% CI, 1.132-8.207; P = .03), and having non-HNSCC metastatic solid cancers (aHR, 1.457; 95% CI, 1.292-1.644; P < .001) were significant risk factors for 90-day mortality. Risk scores were categorized as very low risk (score of 0), low risk (score 1-3), moderate risk (score 4-6), and high risk (score ≥7), with 90-day mortality rates of 3.37%, 5.00% to 10.98%, 16.15% to 29.13%, and 33.93% to 37.50%, respectively. Mortality rates for patients with the same risk score in the training and test data sets were similar (score of 0, 3.27% vs 3.66%; score of 6, 27.42% vs 25.00%). Conclusions and Relevance: In this prognostic study, a 90-day mortality scoring system accurately predicted 90-day mortality among patients with locally advanced HNSCC who completed CCRT.