Association of surgeon volume and hospital volume with the outcome of patients receiving definitive surgery for colorectal cancer: A nationwide population-based study

BACKGROUND Patients with colorectal cancer (CRC) who undergo cancer surgeries with higher-volume providers may have better outcomes. The current debate focuses on whether it is hospital volume or surgeon volume that matters more. METHODS The authors conducted a nationwide population-based study in Taiwan that enrolled all patients who underwent definitive surgery for newly diagnosed CRC between 2005 and 2011. All patients were divided into 4 quartiles according to hospital and surgeon volume. The main outcome was the 5-year mortality rate, which was analyzed using a frailty model for Cox regression. The authors also conducted fixed and random effects multivariate regression models to examine short-term outcomes and resource use, including operative mortality, hospital stay, emergency department visits within 30 days, and medical expenses. Analyses were adjusted for patient and provider characteristics. RESULTS A total of 61,728 patients with CRC were included in the current study. The 5-year mortality rates were 38.7%, 32.8%, 32.0%, and 29.1% in descending order of hospital volume quartiles and were 41.4%, 34.1%, 29.8%, and 27.4% in descending order of surgeon volume quartiles. After adjustment for the individual and provider characteristics, surgeon volume, but not hospital volume, remained a significantly predictive factor of death (P<.001). In addition, those patients with CRC who underwent definitive surgeries performed by higher-volume surgeons had a relatively lower risk of operative mortality, shorter hospital length of stay, and lower medical expenses. CONCLUSIONS Patients with CRC who underwent definitive surgery performed by higher-volume providers were found to have better outcomes. Surgeon volume may play a more important role than hospital volume. Cancer 2015;121:2782-2790.