Timing of Perioperative Chemotherapy Does Not Influence Long-Term Outcome of Patients Undergoing Combined Laparoscopic Colorectal and Liver Resection in Selected Upfront Resectable Synchronous Liver Metastases

Background: The aim of this study was to compare patients undergoing combined colorectal and hepatic surgery with and without neoadjuvant chemotherapy to clarify the prognostic advantage of preoperative oncological treatment in a case-matched analysis using propensity scores and to identify factors predictive of good prognosis in a selected population of Synchronous ColoRectal Liver Metastases (SCRLM). Methods: A total of 73 patients who underwent upfront elective combined surgery without preoperative CT for SCRLM in two European tertiary referral centers were selected and constituted the study group (NoNACT group). The NoNACT group was matched (ratio 1:1) with patients who were operated after chemotherapy with neoadjuvant intent (NACT group, the control group). The matching was achieved based on six covariates representative of patients and disease characteristics. Results: While the characteristics of both colorectal and hepatic procedures were similar, the NoNACT group, as compared to the NACT group, had lower blood loss (200 mL vs. 550 mL). Postoperative stay (9 vs. 12 days) and morbidity rate (24.7% vs. 32.9%) were reduced in the NoNACT compared with the NACT group. Mid- and long-term outcomes were comparable. At multivariable analysis, predictors of long-term outcome were: right colonic neoplasms, RAS mutational status, CRS score ≥3 and the absence of perioperative chemotherapy. Conclusion: Preoperative neoadjuvant chemotherapy in patients with colorectal cancer and synchronous resectable liver metastases does not influence the risk of recurrence in patients with favorable tumor biology, while it was associated with increased intraoperative blood loss and morbidity. There is no strong evidence to recommend upfront chemotherapy in the absence of negative prognostic factors.