Splenic volume may be a useful indicator of the protective effect of bevacizumab against oxaliplatin-induced hepatic sinusoidal obstruction syndrome

AimsThe aim of this study was to investigate the relationship between the use of bevacizumab (Bmab) in addition to oxaliplatin (OX), the development of sinusoidal obstruction syndrome (SOS) and the changes in splenic volume as an indicator of the protective effect of Bmab against OX-induced SOS.MethodsSeventy-nine patients who received OX-based chemotherapy with (OX + Bmab group: n = 48) or without Bmab (OX group: n = 31) for colorectal liver metastases were included in this study. The changes in splenic volume after chemotherapy were evaluated in the two groups. Furthermore, the relationship between the changes in splenic volume and SOS were analyzed in the 55 patients who underwent hepatectomy.ResultsA significant increase in the splenic volume was observed in the OX group, but not in the OX + Bmab group. The increase in the splenic volume relative to baseline was significantly higher in the OX group than in the OX + Bmab group (39.1% vs. 2.3%, p < 0.0001). The incidence of moderate or severe SOS was significantly higher in the OX group than in the OX + Bmab group (50.0% vs. 16.0%, p = 0.0068), and the increase in the splenic volume was significantly higher in the patients with SOS than in those without SOS (42.9% vs. 9.9%, p = 0.0001). A multivariate analysis identified the increase in the splenic volume as an independent predictor of the development of SOS. Conclusions: This study demonstrated that the inhibition of splenic volume enlargement might be a useful indicator of the protective effect of Bmab against OX-induced SOS.