Disparities in Compliance With National Guidelines for the Treatment of Malignant Pleural Mesothelioma

Current guidelines support cancer-directed surgery, chemotherapy, or active surveillance for clinical stages 1 to 3 of epithelial malignant pleural mesothelioma (MPM). Definitive chemotherapy is recommended for sarcomatoid/biphasic histologies. Our objective is to assess compliance with recommendations, measuring their impact on overall survival.

The National Cancer Database participant user file (2004 to 2014) was queried for patients diagnosed with MPM clinical stages 1 to 3. Multivariable logistic regression model identified factors independently associated with guideline compliance. Kaplan-Meier analysis and Cox proportional hazards were used for overall survival comparison with histologic subgroup analysis.

A total of 3419 patients with clinical stages 1 to 3 met criteria for analysis and comprised epithelial (68.5%), sarcomatoid (17.2%), and biphasic subtypes (14.3%). Cancer-directed surgery was significantly underutilized in epithelial MPM, with 29.3% having no treatment. On multivariable analysis, insurance status and facility type were the strongest predictors of guideline compliance. High-volume hospitals were the most compliant with guidelines (odds ratio 3.58, 95% confidence interval (CI), 2.34 to 5.49, P < .001). Median survival estimates for no treatment, chemotherapy alone, surgery plus chemotherapy, and trimodal therapy were 10.2, 15.4, 21.1, and 21.7 months, respectively (log rank P < .001). In epithelial MPM, a significant increase in overall survival was observed in surgery plus chemotherapy (hazard ratio 0.62, 95% CI, 0.53 to 0.73, P < .001) and trimodality (hazard ratio 0.61, 95% CI, 0.49 to 0.76, P < .001; reference: no treatment).

There is a suboptimal compliance with national guidelines for the treatment of MPM, particularly in low-volume nonacademic settings. Adherence to recommended surgery-based multimodal therapy is associated with an overall survival improvement.