[Preoperative Chemotherapy and Risk Factors for Colorectal Liver Metastases]

Between February 2007 and December 2013, 65 liver resections for colorectal metastases were performed in our institution. Preoperative chemotherapy was conducted in 47 patients, of whom 42 were treated with modified FOLFOX6 (mFOLFOX6)-based preoperative chemotherapy. For cases of solitary tumors smaller than 2 cm that are located in the liver surface area, we selected upfront surgery. In the patients who underwent preoperative chemotherapy and upfront surgery, the 3-year OS was 73.9% (Grade A: 81.8%, Grade B: 77.8%, and Grade C: 0%) and the 5-year OS was 62.5%. The 3-year OS in the preoperative chemotherapy group was 63.3%. OS did not differ significantly between the patients who were grouped according to the time of metastasis onset or the extent of metastasis according to the Japanese classification. In the multivariate analysis, no statistical differences were found between the risk factors for recurrence. However, further follow up is needed. Moreover, we believe that the relationships of morphological response to chemotherapy, pathological response, and clinical prognosis should be assessed in the future.