Risk-Adjusted Margin Positivity Rate as a Surgical Quality Metric for Non-Small Cell Lung Cancer

Ann Thorac Surg. 2017 Oct;104(4):1161-1170. doi: 10.1016/j.athoracsur.2017.04.033. Epub 2017 Jul 12.

Abstract

Background: Incomplete lung cancer resection connotes poor prognosis; the incidence varies with patient demographic, clinical, and institutional factors. We sought to develop a valid, survival impactful, facility-based surgical quality metric that adjusts for related patient demographic and clinical characteristics.

Methods: Facilities performing resections for patients diagnosed with stage I to IIIA non-small cell lung cancer in the National Cancer Data Base between 2004 and 2011 were identified. Multivariate logistic regression modeling was used to estimate the expected number of margin-positive cases by adjusting for patient risk mix and calculate the observed-to-expected ratio for each facility. Facilities were categorized as outperformers (observed-to-expected ratio less than 1, p < 0.05), nonoutliers (p > 0.05), and underperformers (observed-to-expected ratio greater than 1, p < 0.05); and their characteristics across performance categories were compared by χ2 tests. Multivariate Cox proportional hazard analyses were conducted, adjusting for patient demographic and clinical characteristics.

Results: A total of 96,324 patients underwent surgery at 809 facilities. The overall observed margin-positive rate was 4.4%. Sixty-one facilities (8%) were outperformers, 644 (80%) were nonoutliers, and 104 (13%) were underperformers. One third (36%) of National Cancer Institute-designated facilities, 13% of academic comprehensive cancer programs, 5% of comprehensive community cancer programs, and 13% of "other" facilities achieved outperforming status but no community cancer programs did. Interestingly, 9% of National Cancer Institute-designated facilities and 11% of academic comprehensive cancer program facilities were underperformers. Adjusting for patient demographic and clinical characteristics, outperformers had a 5-year all-cause hazard ratio of 0.88 (95% confidence interval: 0.85 to 0.91, p < 0.0001) compared with nonoutliers, and 0.80 (95% confidence interval: 0.77 to 0.84, p < 0.0001) compared with underperformers.

Conclusions: Facility performance in lung cancer surgery can be captured by the risk-adjusted margin-positivity rate, potentially providing a valid quality improvement metric.

MeSH terms

  • Aged
  • Carcinoma, Non-Small-Cell Lung / mortality
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Carcinoma, Non-Small-Cell Lung / surgery*
  • Cohort Studies
  • Databases, Factual
  • Disease-Free Survival
  • Female
  • Humans
  • Logistic Models
  • Lung Neoplasms / mortality
  • Lung Neoplasms / pathology*
  • Lung Neoplasms / surgery*
  • Male
  • Margins of Excision*
  • Middle Aged
  • Multivariate Analysis
  • Neoplasm Invasiveness / pathology
  • Neoplasm Staging
  • Pneumonectomy / methods
  • Prognosis
  • Quality Indicators, Health Care*
  • Retrospective Studies
  • Risk Adjustment
  • Survival Analysis
  • Treatment Outcome