Gastric antral vascular ectasia (GAVE) is an angiodysplastic disorder that causes gastric bleeding. GAVE can develop as a complication of hematopoietic stem cell transplantation (HSCT-GAVE), and it has been suggested that it may be associated with oral administration of busulfan. We report two cases of HSCT-GAVE after a conditioning regimen containing intra-venous busulfan (ivBu), not oral busulfan. The first case, a 42-year-old woman with blastic plasmacytoid dendritic cell neoplasm, underwent second allogeneic HSCT with conditioning regimen consisting of cyclophosphamide (120 mg/kg) and ivBu (12.8 mg/kg). HSCT-GAVE developed on day 84 post-transplant, and argon plasma coagulation (APC) was performed successfully. The second case, a 60-year-old woman with acute myelogenous leukemia, underwent allogeneic HSCT with the conditioning regimen consisting of ivBu (12.8 mg/kg) and fludarabine (150 mg/kg). She developed melena and was diagnosed with GAVE by endoscopy on day 145 post-transplant. Although complete hemostasis was not achieved despite four administrations of APCs, the melena spontaneously terminated on day 235 post-transplant. To our knowledge, this is the first report describing HSCT-GAVE after ivBU-based HSCT. Although there is no established therapy for HSCT-GAVE, APC may be an option for HSCT-GAVE.

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by complement (C')-induced lysis of PNH red blood cells (RBCs), which are deficient in the expression of CD55 and CD59. Surgery is one of the major clinical situations that trigger hemolytic attack and thrombosis in PNH. We describe here a case of 64-year-old man with classic PNH complicated by early-stage gastric cancer requiring distal gastrectomy under general anesthesia. We administered humanized monoclonal anti-C5 antibody (eculizumab; Soliris) for a limited period (600 mg, once a week × four times) perisurgically. Eculizumab effectively inhibited the C' system and the patient underwent a curative distal gastrectomy without significant surgery-triggered hemolytic attack. Although discontinuation of eculizumab induced mild hemolysis 2 weeks after the last administration, it was treated conservatively without thrombotic complication. Limited-term induction of eculizumab could be an option for PNH patients with transient and anticipated high risks, with careful preparation for the discontinuation-related risks afterwards.