Association of compliance with process-related qualitymetrics and improved survival in oral cavity squamous cell carcinoma

IMPORTANCE Qualitymetrics for patients with head and neck cancer are available, but it is unknown whether compliance with these metrics is associated with improved patient survival. OBJECTIVE To identify whether compliance with various process-related qualitymetrics is associated with improved survival in patients with oral cavity squamous cell carcinoma who receive definitive surgery with or without adjuvant therapy. DESIGN, SETTING, AND PARTICIPANTS A retrospective cohort studywas conducted at a tertiary academic medical center among 192 patients with previously untreated oral cavity squamous cell carcinoma who underwent definitive surgery with or without adjuvant therapy between January 1, 2003, and December 31, 2010. Data analysis was performed from January 26 to August 7, 2015. INTERVENTIONS Surgery with or without adjuvant therapy. MAIN OUTCOMES AND MEASURES Compliance with a collection of process-related quality metrics possessing face validity that covered pretreatment evaluation, treatment, and posttreatment surveillance was evaluated. Association between compliance with these qualitymetrics and overall survival, disease-specific survival, and disease-free survival was calculated using univariable and multivariable Cox proportional hazards analysis. RESULTS Among 192 patients, compliance with the individual qualitymetrics ranged from 19.7%to 93.6%(median, 82.8%). No pretreatment or surveillance metrics were associated with improved survival. Compliance with the following treatment-related qualitymetrics was associated with improved survival: elective neck dissection with lymph node yield of 18 or more, no unplanned surgery within 14 days of the index surgery, no unplanned 30-day readmissions, and referral for adjuvant radiotherapy for pathologic stage III or IV disease. Increased compliance with a "clinical care signature" composed of these 4metrics was associated with improved overall survival, disease-specific survival, and disease-free survival on univariable analysis (log-rank test; P < .05 for each). On multivariable analysis controlling for pT stage, pN stage, extracapsular spread, margin status, and comorbidity, increased compliance with these 4metrics was associated with improved overall survival (100% vs ≤50% compliance: adjusted hazard ratio [aHR], 4.2; 95%CI, 2.1-8.5; 100% vs 51%-99% compliance: aHR, 1.7; 95%CI, 1.0-3.1), improved disease-specific survival (100% vs≤50% compliance: aHR, 3.9; 95%CI, 1.7-9.0; 100% vs 51%-99%: aHR, 1.3; 95%CI, 0.6-2.9), and improved disease-free survival (100% vs≤50% compliance: aHR, 3.0; 95%CI, 1.5-5.8; 100% vs 51%-99%compliance: aHR, 1.6; 95%CI, 0.9-2.7). CONCLUSIONS AND RELEVANCE Compliance with a core set of process-related qualitymetrics was associated with improved survival for patients with surgically managed oral cavity squamous cell carcinoma. Multi-institutional validation of these metrics is warranted.