Objectives: To validate National Comprehensive Cancer Network ovarian cancer guideline adherence as a quality process measure associated with improved survival, and to identify structural health care characteristics predictive of adherence to National Comprehensive Cancer Network guideline care.
Methods: Consecutive patients with epithelial ovarian cancer diagnosed between 1 January 1999 and 31 December 2006 were identified from the California Cancer Registry. Adherence to National Comprehensive Cancer Network guideline care was defined by stage-appropriate surgical procedures and recommended chemotherapy. Multivariable logistic regression models were used to identify characteristics predictive of National Comprehensive Cancer Network guideline adherence and ovarian cancer-specific survival.
Results: A total of 13,321 patients were identified. Overall, 37.2% of patients received National Comprehensive Cancer Network guideline-adherent care. Guideline-adherent care was associated with high-volume hospitals (20 or more cases per year; 50.8% compared with 34.1%; P<.001) and high-volume physicians (10 or more cases per year; 47.6% compared with 34.5%; P<.001). After controlling for other factors, both low-volume hospitals (odds ratio [OR] 1.83, 95% confidence interval [CI] 1.66-2.01) and low-volume physicians (OR 1.19, 95% CI 1.07-1.32) were independently associated with deviation from National Comprehensive Cancer Network guidelines. On multivariable survival analysis, nonadherence to National Comprehensive Cancer Network guideline care was associated with decreased disease-specific survival (hazard ratio [HR] 1.33, 95% CI 1.26-1.41). Both low-volume hospitals (HR 1.08, 95% CI 1.01-1.16) and low-volume physicians (HR 1.18, 95% CI 1.09-1.28) were associated with decreased disease-specific survival after adjusting for National Comprehensive Cancer Network guideline-adherent care.
Conclusions: Adherence to National Comprehensive Cancer Network guidelines for treatment of ovarian cancer is correlated with improved survival and may be a useful process measure of quality cancer care. Ovarian cancer case volume correlates with a higher likelihood of recommended care and improved survival and may be a useful structural quality measure. Increased efforts to concentrate ovarian cancer care are warranted.