Low Hospital Volume Is Associated with Higher All-Cause Mortality in Black Women with Triple Negative Breast Cancer.

Introduction: This study examines the association between hospital volume and all-cause mortality in Black women with triple negative breast cancer (TNBC) who received surgery and chemotherapy.

Methods: Black women ages 18+ with stage I-III TNBC who received both surgery and chemotherapy were identified in the National Cancer Database (NCDB). Hospital volume was determined using the number of annual breast cancer cases divided by the number of years the hospital participated in the NCDB. Hospital annual volume quartiles ranged from Q₁ (lowest) to Q₄ (highest). Univariable analysis and multivariable logistic regression modeling with restricted cubic splines examined the effect of hospital volume on all-cause mortality.

Results: Sixteen thousand five hundred fifty-six patients met the study criteria. All-cause mortality incidence was lower at higher volume compared to lower volume hospitals Q₁ 24.1% (95% CI: 22.8 to 25.4), Q₂ 21.8% (95% CI: 20.5 to 23.1), Q₃ 20.9% (95% CI: 19.6 to 22.1), Q₄ 19.0% (95% CI: 17.7 to 20.1), p<0.001. On multivariable analysis, treatment at the highest hospital volume quartile was associated with a 21% reduction in the odds of death compared to the lowest quartile [Q₄ Vs. Q₁, OR=0.79 (95% CI: 0.67 to 0.92)]. For every 100-patient increase in annual volume, all-cause mortality was reduced by 4% [OR=0.96 (95% CI: 0.94 to 0.98)]. There was a significant linear dose-dependent relationship between increasing hospital volume and all-cause mortality.

Conclusion: Black women treated at high-volume hospitals have lower all-cause mortality than those at low-volume hospitals. Future studies should examine the characteristics of high-volume hospitals associated with improved outcomes.