Inclusion Criteria:

1. Patients who have received the information leaflet and signed the consent form

2. ≥ 18 years of age with a life expectancy of at least 10 years

3. Performance Status (ECOG) ≤ 2

4. Radical prostatectomy (RP) with or without extended pelvic lymphadenectomy in the 3
months preceding inclusion

5. Histologically confirmed prostatic adenocarcinoma

6. Patients with postoperative Gleason score > 7, or ≥ 7 with the presence of high-grade
Gleason patterns (5) and R0, N0 or Nx , M0 or Patients pT3b, R0, N0 or Nx , M0
whatever the Gleason score

7. Postoperative PSA < 0.1 ng/mL (dosage perform within 2 months after surgery)

8. Neutrophils ≥ 1500/mm3, platelets ≥ 100 000/mm3

9. Bilirubin ≤ upper normal limit (this will not apply to subjects with Gilbert's
syndrome, persistent or recurrent hyperbilirubinemia that is predominantly
uncongugated in the absence of evidence of hemolysis or hepatic pathology); ASAT and
ALAT ≤ 1.5 times upper normal limit;
Creatinine < 140 µmol/l (or clearance > 60mL/min)

10. Patients affiliated to a social security scheme

Exclusion Criteria:

1. Previous treatments for prostatic adenocarcinoma (HT or orchyectomy or CT)

2. Presence of metastases:

- positive bone scintigraphy, including Patients with medullary compression and/or

- abdominal-pelvic CT scan or MRI showing lymph node and/or visceral involvement.

3. History of cancer, with the exception of basal cell carcinoma or any other cancer
treated in the 5 years before inclusion and in complete remission.

4. Incompatible concomitant treatment(s)

5. Hypersensitivity to other GnRH agonists and/or any of the excipients of Eligard®

6. Any illness or problem including geographic, psychiatric or psychological which is
incompatible with being monitored during the trial

7. Persons deprived of their freedom or under supervision (including guardianship),

8. Patients already included in another therapeutic trial with an experimental drug or
having been given an experimental drug within a period of 30 days.