DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate meeting the following criteria:

  • Stage I-II disease (T1-T2c) at initial diagnosis (prior to external-beam radiotherapy), meeting one of the following criteria:

    • Gleason score 7 and prostate-specific antigen (PSA) ≤ 10 ng/mL
    • Gleason score 2-6 and PSA ≤ 20 ng/mL

  • Locally recurrent disease > 30 months after completion of prior external-beam radiotherapy

    • Has undergone prostate biopsy within the past 180 days
• Prostate volume ≤ 45 mL as measured by transrectal ultrasound
• International Prostate Symptom Score < 15
• Baseline serum PSA < 10 ng/mL within 8 weeks prior to study entry OR within 8 weeks prior to initiation of hormonal therapy OR more than 10 days prior to prostate biopsy

• No histologic or radiologic evidence of tumor involvement of regional lymph nodes (N1)

  • Negative lymph nodes by imaging (pelvic with or without abdominal CT scan or MRI), or by nodal dissection (laparoscopy or laparotomy) within the past 8 weeks
• No clinical and/or radiologic evidence of extraprostatic disease at initial diagnosis (i.e., prior to external-beam radiotherapy) or at the time of local recurrence (i.e., prior to study entry)
• No evidence of bone metastases (M0) on bone scan within the past 8 weeks or other metastatic disease (M1)

PATIENT CHARACTERISTICS:

• Zubrod performance status 0-1
• Must be suitable for spinal or general anesthesia

• No prior invasive (except nonmelanoma skin cancer) or hematological (e.g., acute leukemia, aggressive lymphoma, myeloma) malignancy unless disease-free for ≥ 3 years

  • Prior low-grade lymphoma or chronic lymphocytic leukemia allowed
• No persistent late gastrointestinal or genitourinary toxicity ≥ grade 2

• No severe, active comorbidity, including any of the following:

  • Unstable angina and/or decompensated congestive heart failure
  • Myocardial infarction within the past 6 months
  • Bacterial or fungal infection requiring intravenous antibiotics
  • Chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy
  • Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects
  • Acquired immune deficiency syndrome (AIDS)

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No prior transurethral resection of the prostate
• No prior radionuclide (permanent or temporary implantation) prostate brachytherapy
• No prior prostatectomy or prostatic cryosurgery
• No prior high-intensity focused ultrasound
• No prior bilateral orchiectomy
• No prior chemotherapy for prostate cancer
• At least 2 months but ≤ 6 months since initiation of prior luteinizing hormone-releasing hormone agonist
• Any combination of prior neoadjuvant, concurrent, or adjuvant androgen suppression therapy at the time of initial diagnosis and external-beam radiotherapy allowed provided the total duration of treatment was ≤ 8 months
• No prior external-beam radiotherapy to the prostate that exceeds 72 Gy (2 Gy fractions) or 75.6 Gy (1.8 Gy fractions)