Plasma protein C is a useful clinical marker for hepatic veno‐occlusive disease (VOD) in stem cell transplantation

Background Hepatic veno‐occlusive disease (VOD) is one of the most serious complications in stem cell transplantation (SCT). Although plasma protein C activity decreases in VOD after SCT, the timeframe of plasma protein C activity decreases during SCT is not known. Procedure We examined levels of plasma protein C serially during the course of SCT to determine the critical level and risk factors for VOD. Results Of 151 children who received SCT, 12 of them (7.9%) developed VOD. The mean minimum protein C activity in patients with VOD was significantly lower compared to that in patients without VOD ( P  < 0.0001). Receiver operating characteristic curve analysis revealed that the critical plasma protein C activity (cut‐off point) for VOD was identified to be 34.5% with high sensitivity (100%) and specificity (83.3%), and the reduction of plasma protein C below the cut‐off level (day +6.50 ± 2.43) was observed mostly prior to the onset of VOD (day +7.33 ± 2.64). The patients receiving melphalan in conditioning were found to be at high risk for VOD ( P  = 0.003). Among the melphalan containing regimens, melphalan + carboplatin + etoposide was a significant risk factor for depression of plasma protein C ( P  = 0.037). Conclusion Plasma protein C level was a useful parameter of VOD after SCT, and activity below 34.5% was critical for VOD. The use of melphalan in conditioning causes a high risk for VOD. Pediatr Blood Cancer 2010;54:437–443. © 2009 Wiley‐Liss, Inc.