There were 8,986 patients identified with stage I NSCLC who fulfilled our inclusion criteria. The mean age was 75 ± 5 years and 53% were women. The majority of patients underwent anatomic resection (87.2%) and the remainder underwent nonanatomic resection (12.8%) (). The use of nonanatomic resection increased significantly over time, from 11.0% in 2000 to 15.9% in 2007 (p = 0.008). After stratifying by tumor size (< 2 cm, 2 to ≤ 3 cm, and > 3 cm), the use of nonanatomic resections increased from 2000 to 2007 in all tumor sizes, but this trend was significant only among patients with tumors greater than 3 cm (p = 0.04) (). The use of nonanatomic resection for smaller tumors did not increase significantly during the same period. In the multivariable analysis, more wedge resections were performed in 2007 than in 2000 (OR, 1.73; 95% CI, 1.27–2.37).
Unadjusted Analysis Comparing Use of Nonanatomic Resections Among Specific Subgroups According to Patient, Clinical, and Provider Factorsa
Frequency of nonanatomic resections from 2000 to 2007 grouped according to size of the primary tumor.
In the bivariate analysis, race was associated with the receipt of a nonanatomic resection (p < 0.001) (). However the pairwise comparison of the receipt of wedge resections between the 14.5% of black patients and the 13% of white patients was not significant. In the multivariable analysis, race was not associated with the receipt of a nonanatomic resection (). In both bivariate and multivariable analysis, advanced age was associated with the increased use of nonanatomic resections (OR for 80 – 84 years versus 67– 69 years, 1.51; 95% CI, 1.15–1.98; ≥ 85 years, 1.91; 95% CI, 1.31–2.82). Although some other sociodemographic factors were associated with the receipt of a nonanatomic resection on bivariate analysis (), they were not associated with nonanatomic resections in multivariable analysis.
Factors Associated With Nonanatomic Resections in Multivariable Analysisa
Clinical factors significantly associated with the receipt of nonanatomic resections in bivariate analysis included hospital admission for COPD in the year before resection, hospital admission from all causes in the previous year, receipt of flu vaccine, PFT testing, V/Q scans, and invasive mediastinal staging (each p < 0.05) (). Among the 31 comorbid conditions, 9 conditions were significant and 2 additional conditions were marginally significant. Of the 11 comorbid conditions with unadjusted p values less than 0.10, only COPD was found to be significantly associated with receipt of nonanatomic resections after adjusting for the other factors (). In multivariable analysis, performance of V/Q scans (OR, 1.56; 95% CI, 1.55–2.12) was associated with the receipt of nonanatomic resections.
In terms of tumor characteristics, patients with smaller tumor size were significantly more likely to undergo nonanatomic resections (p < 0.001). After stratifying by tumor size, the temporal trend in the use of nonanatomic resection remained significant only among patients with tumors larger than 3 cm. Patients undergoing nonanatomic resections also had fewer lymph nodes examined (p < 0.001).
Among provider factors, bivariate analysis demonstrated that patients whose resections were performed at a hospital performing a higher volume of resections (p < 0.001) or whose procedures were not performed by a thoracic surgeon (p = 0.02) were more likely to undergo nonanatomic resections (). In the multivariable analysis, the highest quintile for hospital volume was the only provider prognostic factor for nonanatomic resection (OR, 1.58; 95% CI, 1.23–2.04) (). The absolute number of hospitals decreased from lowest to highest quintile of lung resection volume. The percentage of teaching hospitals, urban hospitals, and patients treated by a thoracic surgeon, however, increased with quintile of volume (data not shown).
Adjusted odds ratios for receipt of nonanatomic resection according to quintiles of hospital volume. The first quintile is the reference quintile.
A subgroup analysis was performed, focusing on age, COPD diagnosis, and tumor size, which were all independently associated with nonanatomic resections. Patients 80 years of age or older underwent nonanatomic resection more often than did patients younger than 80 years of age, and the same was true among patients with COPD and those without (). The greatest disparity occurred among patients with the smallest tumors (≤ 2 cm). Among patients with COPD, 28% of patients younger than 80 years of age versus 35% of patients older than 80 years of age received anatomic resections (p = 0.06). Among patients without COPD, 14% of patients younger than 80 years of age versus 24% of patients 80 years of age or older received anatomic resections (p < 0.001).
Use of nonanatomic resection according to tumor size and chronic obstructive pulmonary disease (COPD) status.