難治性精巣腫瘍に対する etoposide 大量療法を用いた効率的な自家末梢血幹細胞採取法の確立

: Clinical effects of peripheral blood stem cell autotransplantation (PBSCT) after ultra high-dose chemotherapy were evaluated in patients with chemotherapy-resistant and/or poor prognostic testicular cancer. Four patients with testicular cancer, who had high-risk malignancy, were treated with high-dose etoposide (500 mg/m2 x 4 days) in order to collect peripheral blood stem cells. After the administration of high-dose etoposide, rG-CSF (250 micrograms/body) was administered from nadir state. Blood mononuclear cells were collected using a Fenwall CS-3000 blood cell separator. Fractions enriched for stem cells were obtained by discontinuous Percoll gradient centrifugation and were stored in liquid nitrogen using patient's sera and DMSO. The mean number of peripheral blood granulocyte-macrophage-colony-forming units (CFU-GM) collected by one apheresis was 22.3 x 10(5)/kg body weight. In addition, CFU-GM more than 2.0 x 10(5)/kg body weight could be collected in each apheresis, which was though to be sufficient dosis to perform PBSCT in safe, based upon our previous studies. All the patients were treated by a combination of cisplatin (20 mg/m2 x 5 days), etoposide (100 mg/m2 x 5 days) and bleomycin (15 mg x 3 days). Three patients responded to BEP therapy and obtained a CR, however, remaining 1 patient failed to achieve CR, who was later treated by ultrahigh-dose chemotherapy including carboplatin (200 mg/m2 x 4 days), etoposide (250 mg/m2 x 4 days) and cyclophosphamide (50 mg/kg x 2 days) followed by PBSCT. He responded to this therapy and obtained a CR for 10 months. The results suggested the method was promising for patients with chemotherapy-resistant and/or poor prognostic testicular cancer.