Facility Volume Thresholds for Optimization of Short- and Long-Term Outcomes in Patients Undergoing Hepatectomy for...

Volume-outcome relationships have been described for a variety of surgical procedures. We aimed to define the facility volume threshold at which postoperative mortality after hepatectomy was optimal.

We determined volume percentiles for institutions performing hepatectomy for any primary liver tumor within the National Cancer Database (2004-2017). Marginal structural logistic regression defined the volume percentile (Vmin) at which the odds of 90-day mortality were optimally reduced in patients with hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC). Short-term postoperative and survival outcomes were compared between patients treated at facilities above and below Vmin.

Thresholds for the 10^th/25^th/50^th/75^th/90^th percentiles were 2/7/26/46/59 hepatectomies/year. A total of 17,833 patients underwent resection of HCC or ICC. The 90-day postoperative mortality was optimized at the 75^th percentile for all hepatectomies (IP-weighted OR = 0.67, 95% CI = 0.52-0.87) and major hepatectomy (IP-weighted OR = 0.62, 95% CI = 0.49-0.80). Seven of 446 facilities met the Vmin threshold. The odds of 30-day mortality were also reduced for all hepatectomies (IP-weighted OR = 0.55, 95% CI = 0.42-0.73) and major hepatectomy (IP-weighted OR = 0.58, 95% CI = 0.41-0.75). There were no differences in length of stay or 30-day readmission rate. Patients with HCC or ICC treated at facilities ≥ 10^th percentile had an associated improvement in overall survival.

Resection of HCC and ICC is performed at a large number of facilities. Postoperative mortality is optimally reduced at facilities performing at least 46 liver operations annually. Regionalization of surgical care among patients with primary liver malignancies to high-volume centers may result in improved outcomes.