Acknowledgements Disclosure: The authors declare no conflict of interest.
Oxaliplatin and 5-fluorouracil/leucovorin (FOLFOX),

with or without bevacizumab (BEV), has been shown to improve the response rates, progression-free survival, and overall survival in patients with stage IV or recurrent colorectal cancer (1,2). Capecitabine combined with oxaliplatin (XELOX) has also been shown to be non-inferior to FOLFOX4 as the first line treatment for patients with metastatic colorectal cancer (NO16966) (3). In patients with colorectal liver metastases, survival benefits were suggested when these regimens were used in a neoadjuvant or conversion setting before Inhibitors,research,lifescience,medical hepatectomy (4-6). However, oxaliplatin-induced hepatotoxicity, i.e., sinusoidal obstruction syndrome (SOS) is now commonly recognized as an adverse event related to these treatments (7), and must be carefully considered due to its association with a higher incidence of postoperative complications, especially hepatic insufficiency, Inhibitors,research,lifescience,medical after a major hepatectomy (8,9). Among the factors predicting SOS after chemotherapy, oxaliplatin-induced splenomegaly (10) is considered to be important because the grade of splenomegaly is associated with the Inhibitors,research,lifescience,medical severity of oxaliplatin-induced SOS (11). In addition, the ratio of aspartate aminotransferase to platelets

(APR), thus indicating liver fibrosis due to chronic hepatitis (12), has been shown to be a simple predictor of oxaliplatin-induced SOS (13). Among the various predictors of oxaliplatin-induced SOS Inhibitors,research,lifescience,medical recognized after chemotherapy, no single factor can predict the development of adverse events before oxaliplatin-based chemotherapy, although a gene polymorphism has been shown to be associated with adverse events after use of the FOLFIRI regimen (14). This is important, because the choice of whether or not to perform preoperative chemotherapy for patients with initially resectable colorectal liver metastases could be made based on the likelihood of adverse events if a predictor of Inhibitors,research,lifescience,medical SOS could be identified. We recently learn more reported that the APR before

chemotherapy can predict oxaliplatin-induced splenomegaly and also indicate the likelihood of developing adverse events during oxaliplatin-based chemotherapy (15). However, bevacizumab (BEV), a therapeutic antibody used for various cancers, including colorectal cancer, was recently reported to reduce Suplatast tosilate the oxaliplatin-induced splenomegaly (16). Therefore, the aim of the present study was to investigate whether the APR before chemotherapy can predict the development of splenomegaly and adverse events due to FOLFOX/BEV and XELOX/BEV in patients with stage IV or recurrent colorectal cancer. Patients and methods We retrospectively reviewed patients with stage IV or recurrent colorectal cancer treated in our department between June 2007 and December 2011. We focused on patients undergoing chemotherapy consisting of FOLFOX/BEV or XELOX/BEV.