RESUMEN
BACKGROUND: The incidence and clinical features of bilateral germ cell testicular tumor (GCTT) in the Japanese population are not fully characterized. We examined the incidence, clinical features, management and outcome, sexual status, hormonal environment, implication of androgen replacement, and human leukocyte antigen (HLA) typing of bilateral GCTT. METHODS: We treated nine consecutive patients with bilateral GCTT from 1980 through to 1999, and reviewed their hospital and clinic charts. Testosterone, luteinizing hormone, follicle stimulating hormone, dehydroepiandrosterone, and dehydroepiandrosterone-sulfate were measured in bilateral orchiectomized patients. Human leukocyte antigen typing was assessed with peripheral lymphocyte. RESULTS: The incidence of bilateral GCTT against the total number of patients with GCTT was 9/274 (3.3%). The median age of the first tumor was 29 (range 21-75) years. Three cases were synchronous and the remaining six cases were metachronous. In the case of metachronous tumor, the median interval between first and contralateral tumor was 8 (range 2-25) years. Standard treatment was defined as surveillance policy in stage I, chemotherapy for higher stages of non-seminoma, and radiotherapy for stage II seminoma. Human leukocyte antigen typing was examined for seven cases. Five cases were positive for HLA-A24. The incidence of HLA-A24 in bilateral GCTT was identical to that of the Japanese population. The relapsing incidence of stage I disease with surveillance policy was almost identical to unilateral GCTT. A 74-year-old patient with stage II seminoma died of the disease at 1.3 years. The other eight patients remained well without any evidence of recurrence at a median follow-up period of 78 (range 12-204) months. Four patients with bilateral orchiectomy did not require androgen replacement without easy fatigability. Sexual status was conserved using androgen replacement. CONCLUSIONS: Long-term follow-up, as long as 25 years, is recommended for contralateral relapse. Some patients with bilateral orchiectomy do not require androgen replacement. The significance of HLA-A24 for bilateral testicular tumor is equivocal in the Japanese population.