Familial prostate cancer in Japan.

BACKGROUND

Familial prostate cancer has been studied in Europe and the United States. This study was conducted to clarify the clinical features and incidence of the human leukocyte antigen (HLA) in familial prostate cancer in patients seen at hospitals in Japan.

METHODS

The age at diagnosis, clinical stage, histologic differentiation, prognosis, cause of death and family history were compiled from 43 patients from 20 families with familial prostate cancer (group F) and compared in patients with sporadic prostate cancer (group S). In addition, HLA class II gene typing was performed in 17 patients from 11 families with familial prostate cancer (group F') and their healthy family members (15 males and 25 females).

RESULTS

The age at diagnosis was significantly lower in group F patients (P< 0.001), but neither clinical stage nor prognosis differed between group F and group S, yet the incidence of moderately differentiated adenocarcinoma was significantly higher in group F (P< 0.01 ). There were no historical factors that were specific for group F patients. The frequency of HLA-DRB1 *0901 and *1201 alleles was significantly higher in group F' patients than in group J (the frequency of alleles in 1216 Japanese people attending the 11th Japan HLA Workshop), but not between group F' and their healthy male family members.

CONCLUSION

There were no significant differences in clinical parameters between group F and group S, except that the age at diagnosis was lower in group F patients, and that the frequency of several HLA class 11 alleles was significantly higher in patients with prostate cancer. In men with a family history of prostate cancer, examinations for early detection of prostate cancer should begin at a young age.