Abstract

Unusual Extramedullary Relapse after Haploidentical Bone Marrow Transplantation in a Patient with Acute Lymphoblastic Leukemiat

Yasuhiro Ebihara, Shohei Yamamoto, Shinji Mochizuki1, Masao Tsukada, Yuki Taya, Aki Sato, Toshiro Kawakita, Seiko Kato, Jun Ooi, Satoshi Takahashi, Arinobu Tojo and Kohichiro Tsuji

Extramedullary relapse of acute lymphoblastic leukemia (ALL) after allogeneic hematopoietic stem cell transplantation (HSCT) is infrequent. In general, the sites of extramedullary relapse are mainly the central nervous system (CNS) and testis, which are so called sanctuary sites. In sites of extramedullary relapse, renal or pancreatic involvements after HSCT are extremely rare in ALL. Here we described a case of 17 year-old male, who was diagnosed as ALL with the t(1;19)/TCF3-PBX1. At twenty months after the fourth myeloablative HSCT, he had extramedullay relapse, which concurrently occurred in pancreas and bilateral kidneys in spite of maintaining hematological complete remission in bone marrow (BM). He had never had extramedullary replaspe including in CNS and testis before this episode. Concurrent involvement of two solid organs (pancreas and kidney) after HSCT as in the present case has not been described.