The Role of Preoperative Chemotherapy in the Management of Synchronous Resectable Colorectal Liver Metastases: A Meta-Analysis

Background: The indications of preoperative chemotherapy, for initially resectable synchronous colorectal liver metastases, remain controversial. This meta-analysis aimed to assess the efficacy and safety of preoperative chemotherapy in such patients. Methods: Six retrospective studies were included in the meta-analysis with 1036 patients. Some 554 patients were allocated to the preoperative group, and 482 others were allocated to the surgery group. Results: Major hepatectomy was more common in the preoperative group than in the surgery group (43.1% vs. 28.8%, p < 0.001). Furthermore, the percentage of patients with more than three liver metastases was higher in the preoperative group compared to the surgery group (12.6% vs. 5.4%, p < 0.002). Preoperative chemotherapy showed no statistically significant impact on overall survival. Combined disease free/relapse survival analysis of patients with high disease burden (liver metastases > 3, maximum diameter > 5 cm, clinical risk score ≥ 3) demonstrated that there is a 12% lower risk of recurrence in favor of preoperative chemotherapy. Combined analysis showed a statistically significant (77% higher probability) of postoperative morbidity in patients who received preoperative chemotherapy (p = 0.002). Conclusions: Preoperative chemotherapy should be suggested in patients with high disease burden. The number of cycles of preoperative chemotherapy should be low (3–4) to avoid increased postoperative morbidity. However more prospective studies are needed to clarify the exact role of preoperative chemotherapy in patients with synchronous resectable colorectal liver metastases.