This retrospective study on a large number of cases offers a vision of the modalities of care in prostate cancer diagnosed before the age of 55, according to different policies, aiming to propose other directions for 2005. Between January 1974 and December 2001, 365 patients had a pathological diagnosis of prostate cancer occurring before the age of 55. These patients were referred to the departments of radiation therapy affiliated to the Rare Cancer Network. A questionnaire was filled in retrospectively to allow further analysis of medical and surgical data. The treatments were those recommended at the time of analysis and progressed according to new accepted standards. Clinical and pathological features of the patients were as follows: 36% of the tumours were Gleason > 7 scored, 56% of the patients had a T3-T4 and 31 had metastases at the time of diagnosis. As far as treatment was concerned, 4 groups were considered: 83 patients had a radical prostatectomy, 155 received radiation therapy with a curative intent, 87 were treated by hormonal manipulation, and the remaining 40 patients received palliative care. The free of disease survival rate at 10 years was 38% for patients without immediate metastases, only 1% of patients with metastases were alive. The multivariate analysis demonstrated the significant impact of radiotherapy on both local and distant failure rates and of T stage on distant failure rate. Survival was affected by nodal involvement and local failure. A separate analysis of two periods of time (1974-1989 and 1990-2001) did not show any differences in terms of treatment results. This retrospective study suggests that age is not a negative prognostic factor as far as adequate curative treatments are carried out. Therapeutic modalities having considerably evolved in prostate cancer, a further analysis with a longer follow up may allow the evaluation of these treatments on rates of failures and survival. Screening for prostate cancer in family histories is likely to increase the number of cases diagnosed before 55. Therefore, a complete information on morbidity associated to the different means of treatment would lead to a better acceptance of late side effects.