Postoperative complications predict poor outcomes only in patients with a low modified clinical score after resection of colorectal liver metastases: a retrospective cohort study

The aim was to identify the optimal criteria of postoperative complications (POCs) for predicting oncological outcomes after hepatectomy for colorectal liver metastases (CRLMs) and to investigate the variable prognostic implications of POCs according to the modified clinical score (M-CS). We identified 751 patients who underwent curative hepatic resection for CRLM between 2007 and 2018. Patients were categorized based on the M-CS. The impact of the severity [≥ Clavien–Dindo grade (C–D) III or comprehensive complication index (CCI) ≥ 26.2] or type [any infectious complications of POC (Inf-poc)] of POC on overall survival (OS) and recurrence-free survival (RFS) was assessed by univariate and multivariable analyses in different groups. Patients with a major or infectious complication were not associated with either RFS or OS in multivariable analysis of the whole cohort. However, patients with a high CCI had a worse OS (HR 1.51, P = 0.004). Among patients with low M-CS, patients with high CCI had worse OS (HR 1.49, P = 0.035) and RFS (HR 1.32, P = 0.048) than those without high CCI. In contrast, the survival disadvantage of a high CCI was not present in patients with a high M-CS. Compared to Inf-poc or major complications, a high CCI decreased long-term OS in patients treated with hepatectomy for CRLM. High CCI has a variable prognostic impact after hepatic resection for CRLM depending on the M-CS. POC is not a decisive factor to justify the use of hepatectomy for CRLM in patients with high M-CS. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13304-022-01312-7.