Advancing Education, Research, and Quality of Care for the Head and Neck oncology patient.
Background: Cancer cachexia is a catabolic condition which produces weight loss and weakness primarily through skeletal muscle and adipose wasting. It is highly prevalent in advanced head and neck cancer (HNC) patients and has shown to result in worse postoperative complications and response to chemoradiation. However, whether this has any impact on postoperative survival and recurrence in HNC is unknown.
Methods: A single-institution retrospective review from 2014-2019 was performed on patients with non-metastatic, HPV-negative squamous cell carcinoma of the mucosal aerodigestive tract undergoing curative resection and free flap reconstruction. Cachexia was defined as >5% unintentional weight loss over the previous 6 months with or without sarcopenia and underweight BMI. Propensity score matching using the inverse probability of treatment weighting (IPTW) of cachectic and control groups was utilized to adjust and balance pre- and intra-operative covariates. Kaplan-Meier curves and Cox-proportional hazard models were generated to compare 5-year overall (OS), disease-specific (DSS), and disease-free survival (DFS) between groups.
Results: The cohort consisted of 243 primarily white (94.2%) male (66.7%) smokers (79.4%) with advanced overall disease (stage III-IV, 84.8%) most frequently occupying the oral cavity (67.1%). Cachexia was identified in 123 patients (50.6%), and median (interquartile range) follow up was 24.7 (9.0-49.2) months. Prior to IPTW adjustments, the cachectic group had lower BMI, lower performance scores, larger tumors of the larynx and pharynx, greater nodal burden, higher TNM classification, longer operative times, and reconstruction more frequently with osseous and/or muscular flaps. Cachectic patients had significantly lower 5-year OS (HR [95%CI] = 2.00 [1.39-2.87]) and DSS (HR [95%CI] = 1.72 [1.09-2.72]) but not DFS (HR [95%CI] = 1.37 [0.92-2.05]). After IPTW balancing, all covariates between cachectic and non-cachectic groups had non-significant differences (p>0.10) with standardized effect sizes ≤0.10. The adjusted 5-year OS remained worse in cachectic patients (HR [95%CI] = 1.39 [1.06-1.82]), but no difference was identified in the adjusted 5-year DSS (HR [95%CI] = 1.19 [0.86-1.66]) or DFS (HR [95%CI] = 1.17 [0.87-1.57]).
Conclusions: Cachectic HNC patients undergoing resection and free flap reconstruction have worse 5-year OS but comparable 5-year DSS and DFS when matched for confounding variables.