Radiation Therapy in Treating Patients With Stage II Prostate Cancer

OBJECTIVES:

- Compare the overall survival of patients with stage II adenocarcinoma of the prostate
treated with high- vs standard-dose three-dimensional conformal or intensity-modulated
radiotherapy.

- Compare the freedom from prostate-specific antigen failure, disease-specific survival,
local progression, and distant metastases in patients treated with these regimens.

- Compare the probability of tumor control and normal tissue complications in patients
treated with these regimens.

- Compare the incidence of grade 2 or greater genitourinary and gastrointestinal acute and
late toxicity in patients treated with these regimens.

- Compare the quality of life, including sexual function, of patients treated with these
regimens.

- Correlate histopathologic or tumor-specific cytogenetic or chromosomal markers with
cancer control outcomes in patients treated with these regimens.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to
Gleason score and prostate-specific antigen (PSA) level (Gleason score 2-6, PSA ≥10 mg/mL but
< 20 ng/mL vs Gleason score 7, PSA < 15 ng/mL) and radiation modality (three-dimensional
conformal radiotherapy [3D-CRT] vs intensity-modulated radiotherapy [IMRT]). Patients are
randomized to 1 of 2 treatment arms.

- Arm I: Patients undergo standard-dose 3D-CRT or IMRT once daily, 5 days a week, for 7.8
weeks (39 treatment days).

- Arm II: Patients undergo high-dose 3D-CRT or IMRT once daily, 5 days a week, for 8.8
weeks (44 treatment days).

Quality of life (QOL) is assessed initially at baseline. After completion of radiotherapy,
QOL is assessed every 3 months for 1 year and then every 6 months for 4 years.

Patients are followed every 3 months for 2 years, every 6 months for 3 years, and then
annually thereafter.

PROJECTED ACCRUAL: A total of 1,520 patients (760 per treatment arm) will be accrued for this
study within 5 years.

DISEASE CHARACTERISTICS:

- Histologically confirmed adenocarcinoma of the prostate

- Clinical stage T1b-T2b

- Meets one of the following criteria:

- Gleason score 2-6 AND prostate-specific antigen (PSA) ≥ 10 ng/mL but < 20 ng/mL

- Gleason score 7 AND PSA < 15 ng/mL

- No regional lymph node involvement

- No distant metastases

PATIENT CHARACTERISTICS:

Age:

- Any age

Performance status:

- Zubrod 0-1

Life expectancy:

- Not specified

Hematopoietic:

- Not specified

Hepatic:

- Not specified

Renal:

- Not specified

Other:

- No other invasive malignancy within the past 5 years except localized basal cell or
squamous cell skin cancer

- No other major medical or psychiatric illness that would preclude study participation

PRIOR CONCURRENT THERAPY:

Biologic therapy:

- Not specified

Chemotherapy:

- No prior cytotoxic chemotherapy

- No concurrent cytotoxic chemotherapy

Endocrine therapy:

- At least 3 months since prior finasteride

- No other prior hormonal therapy, including:

- Luteinizing hormone-releasing hormone agonists (e.g., goserelin or leuprolide)

- Antiandrogens (e.g., flutamide or bicalutamide)

- Estrogens (e.g., diethylstilbestrol)

- No concurrent (neoadjuvant or adjuvant) hormonal therapy

Radiotherapy:

- No prior pelvic irradiation or brachytherapy

Surgery:

- No prior radical surgery (prostatectomy) or cryosurgery for prostate cancer

- No prior surgical castration (bilateral orchiectomy)

Other:

- At least 3 months since prior finasteride or phytoestrogen preparation (PC-SPES)