Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed adenocarcinoma of the prostate

- Unfavorable disease, defined by at least 1 of the following criteria:

- Clinical stage T3 or T4

- Gleason score ≥ 8

- Serum PSA ≥ 20 ng/mL and ≤ 100 ng/mL

- pN0 disease allowed if lymphadenectomy performed before patient began hormone therapy

- No pelvic lymph nodes ≥ 15 mm by CT scan or MRI

- No axillary lymph node involvement (pN1)

- No bone metastasis

- Must be starting hormonal treatment on or up to 6 months before beginning
radiotherapy

PATIENT CHARACTERISTICS:

- ECOG performance status 0-1

- Life expectancy > 5 years

- Must be enrolled in a social security program

- No other cancer, except basal cell skin cancer, that has been treated or relapsed
within the past 5 years

- No severe uncontrolled hypertension (systolic BP ≥ 160 mm Hg or diastolic BP ≥ 90 mm
Hg)

- No contraindication to luteinizing hormone-releasing hormone agonists

- No contraindication to pelvic irradiation (e.g., scleroderma, chronic inflammatory
gastrointestinal disease)

- No hip prosthesis

- Must not be deprived of liberty or under guardianship

- No geographical, social, or psychological reasons that would preclude follow up

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior pelvic irradiation

- At least 3-4 months since prior transurethral resection

- No other prior surgery for prostate cancer

- No concurrent participation in another clinical trial which would require approval
upon entry to this trial