A Systematic Review of Clinical Response and Survival Outcomes of Downsizing Systemic Chemotherapy and Rescue Liver Surgery in Patients with Initially Unresectable Colorectal Liver Metastases

Background. Selected patients with unresectable colorectal liver metastases (CLM) may be rendered resectable after systemic chemotherapy. We reviewed the evidence of downsizing systemic chemotherapy followed by rescue liver surgery in patients with initially unresectable CLM. Methods. Literature search of databases (Medline and PubMed) to identify published studies of neoadjuvant chemotherapy followed by liver resection in patients with initially unresectable CLM was undertaken and focused on response rate of chemotherapy and survival outcomes. Results. Ten observational studies were reviewed. A total of 1,886 patients with initially unresectable CLM underwent systemic chemotherapy. An objective response was observed in 64% (range, 43-79%) of patients after systemic chemotherapy. Of these, 22.5% underwent macroscopically curative liver resection. Median overall survival was 45 (range, 36-60) months with 19% of patients alive and recurrence-free. Conclusions. Current evidence suggests that downsizing systematic chemotherapy followed by rescue liver resection is safe and effective for selected patients with initially unresectable CLM. Further studies are required to examine response rates and secondary resectability using new targeted molecular therapy-based regimens.