Treatment outcome of metastatic testicular cancer at a single institution in Japan, a country with low incidence of germ cell tumor

Background: Incidence of testicular cancer is low in Japan. Recent investigations showed that the outcome of metastatic testicular cancer is associated with the experience of the treatment institution. Objectives of the present investigation are to evaluate outcome of a single institution in Japan, and to identify prognostic factors for testicular cancer. Methods: We retrospectively analysed the outcome of 74 patients with metastatic testicular cancer who were treated at Tsukuba University Hospital (TUH) between January 1981 and January 2003. Forty-five patients (61%) were referred to the TUH for the treatment of metastatic disease. The progression-free survival (PFS) rates according to the International Germ Cell Cancer (IGCC) classification and the Indiana University classification were used to evaluate the treatment outcome. Results: The median follow-up period of all patients was 87 months (range, 13-260 months). Forty patients (54%) were classified as having good prognosis, 20 (27%) intermediate, and 14 (19%) poor. The overall 5-and 10-year PFS was 79 and 74%, respectively. The 5-year PFS with good, intermediate and poor prognosis was 90, 70 and 64%, respectively. There was a significant difference between the three groups (P = 0.02), but the survival of the intermediate-prognosis group was not statistically different from that of the poor-prognosis group. The Indiana University classification failed to discriminate the prognoses of moderate and advanced disease, but proved to be an independent prognostic factor for progressionfree survival in intermediate-and poor-prognosis patients (P = 0.025, hazard ratio = 5.39). Conclusions: Our treatment outcome is not different from that of the institutions participating in the International Germ Cell Cancer Consensus Group (IGCCCG).