Poor-risk胚細胞腫瘍に対する末梢血幹細胞移植併用大量化学療法の検討

Abstract

胚細胞腫瘍6例に末梢血幹細胞移植併用大量化学療法を施行した.2例が再発症例で, 3例が導入化学療法に抵抗性と判断され, 1例が残存腫瘍が切除不能の縦隔腫瘍症例であった.再発腫瘍の2例ではcPR, cCRが得られたが, 結局再発癌死した.抵抗性の2例においてpCRが得られ, 肺に残存した腫瘍は摘出しなかったが, 23ヵ月, 24ヵ月経過した現在も再発を認めていない.強化地固め療法として行った1例においても, 24ヵ月PRを続けている

Between January 1997 and December 1998, six patients with germ cell tumor were treated with high-dose CEC: carboplatin (1, 500 mg/m2), etoposide (1, 200 mg/m2) and cyclophosphamide (100 mg/kg), followed by peripheral blood stem cell transplantation (PBSCT) at Nagoya University Hospital. Four patients received one cycle of high-dose CEC and two received two cycles. The reasons why the high-dose CEC was administered included: 1) refractory to the induction chemotherapy (AFP/beta-HCG elevated during the induction chemotherapy or prolonged half-life of each marker) in three patients, 2) relapse in two patients, and 3) consolidation in one with unresectable mediastinal residual tumor. There were no treatment-related deaths and grade 1 hepatotoxicity occurred in one (17%) patient. The median duration (range) from PBSCT until a granulocyte count of 500/microL and a platelet count of 50, 000/microL was 8.5 (8-11) and 11 (9-16) days, respectively. Of the six patients studied, 5 responded to the treatment; two achieved a complete response (CR) and three achieved a partial response (PR). One patient achieving a CR and two achieving a PR remained in complete remission after 23 to 24 months of follow-up, while the remaining patients with a CR, a PR and an incomplete response died of the disease. High-dose CEC could be administered without serious toxicity but the effectiveness of high-dose CEC for the poor-risk patients with germ cell tumor needs to be further investigated.