Generally, 15–25% of cases have colorectal liver metastasis (CRLM) at diagnosis.[1, 2] Furthermore, CRLM occurs in 25–50% of cases with the resection of primary colorectal tumor over 3 years.[3-5] Hepatic resection is accepted as the only treatment contributing to the long-term survival and cure of patients with CRLM.[6] However, only 15–20% of patients with CRLM are considered candidates for hepatic resection at the time of presentation.[7-10] The significance of other tumor destruction modalities, such as radiofrequency ablation, remains controversial.[11] Of those patients who

undergo hepatic resection, there are at least two categories of patients with CRLM. The first category is clearly or potentially resectable at the time

of presentation. selleckchem The second category is initially unresectable, but convertible to be resectable after treatment with anticancer agents including molecular targeted agents, which we refer to as “conversion surgery”. The purpose of neoadjuvant chemotherapy for resectable CRLM is to downsize CRLM lesions and maximize the remnant liver as well as to reduce the residual micrometastasis, while less extensive resections can be carried out in keeping with the curative intent. However, until now, the role of neoadjuvant therapy prior to the resection of CRLM is not yet proven and remains controversial. click here The largest prospective trial consisted of 364 patients with less than five initially resectable CRLM (European Organization for Research and Treatment of Cancer Intergroup 40983 trial) randomized with perioperative chemotherapy (four to six preoperative and six postoperative cycles of FOLFOX4) or surgery alone, and showed a clinical benefit in 3-year progression-free survival (36.2% vs 28.1%) but not in 5-year overall survival.[12] The FOLFOX regimen may reduce the risk of events in terms of progression-free survival but not necessarily improve long-term survival compared with surgery alone in eligible and initially resectable patients. On the other hand, regarding initially unresectable CRLM, the “conversion surgery” strategy

has been widely used and accepted. Actually, 5-fluorouracil (5-FU)/leucovorin (LV) plus oxaliplatin (L-OHP); FOLFOX or irinotecan (Iri); FOLFIRI or combination Idelalisib order of both; FOLFOXIRI with or without molecular-targeted agents as preoperative strategy have recently achieved higher conversion rates and better clinical outcomes.[13-20] Particularly in L-OHP-based chemotherapy, the conversion rate ranged 7–51% in patients with unresectable CRLM. The effectiveness of triple combination chemotherapy, FOLFOXIRI, for patients with initially unresectable CRLM has been reported to have an improved response rate (60% vs 34%) and higher R0 resection rate among patients with CRLM only compared with the FOLFIRI regimen (36% vs 12%).