We herein describe an unusual case of multicentric Castleman's disease accompanied by thrombocytopenia, ascites, renal failure and myelofibrosis in a Japanese woman. The patient was initially diagnosed as having myelodysplastic syndrome with myelofibrosis. The general condition of the patient deteriorated rapidly; however, treatment with tocilizumab, an anti-interleukin-6 receptor antibody, together with corticosteroids dramatically improved her symptoms. The clinical features of this case were similar to those of three cases previously reported by Takai et al. (Rinsho Ketsueki, 2010, 51:320-5), which were determined to be thrombocytopenia, anasarca, fever, reticulin myelofibrosis and organomegaly (TAFRO) syndrome, a possibly distinct clinical entity.