Intensity-Modulated Radiation Therapy in Treating Patients Undergoing Androgen Deprivation Therapy for Metastatic Prostate Cancer

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

  • Stage N1, N2, N3, M1a, M1b, M1c disease with ≤ 5 metastatic lesions

    • If the diagnosis of metastasis is based solely on imaging CT scan or MRI, the longitudinal diameter of the lymph node (LN) must be ≥ 2.0 cm
    • If the LN is positive on PET or Prostascint scan, the longitudinal diameter of the LN must be ≥ 1.5 cm on CT scan or MRI
• Measurable disease documented by x-rays, scans, or physical examination within the past 28 days OR nonmeasurable disease assessed within the past 42 days

• Has received up to 36 weeks of adjuvant androgen deprivation therapy for metastatic disease OR is planning to receive 36 weeks of adjuvant androgen deprivation therapy

  • Patients who are not receiving androgen deprivation therapy at the time of enrollment undergo androgen deprivation therapy
  • Patients who are already receiving androgen deprivation therapy at the time of enrollment will continue treatment, as described above, until they have received a total of 36 weeks of treatment
  • Patients who have enrolled on study after completion of androgen deprivation therapy or near the end of their treatment course must have serum testosterone level at castrate levels (< 50 ng/dL)
• Documented PSA level > 2 ng/mL prior to onset of androgen deprivation

• No disease that is refractory to hormone therapy, as demonstrated by occurrence of 1 of the following while on luteinizing hormone-releasing agonist therapy:

  • Increase in PSA by 25% over baseline to at least > 2 ng/mL on two consecutive PSA measurements
  • Increase by 20% in the sum of longest diameters of target measurable lesions over the smallest sum observed (over baseline if no decrease during therapy) using the same techniques as were used at baseline
  • Clear worsening of any nonmeasurable disease
  • Reappearance of any lesion that had disappeared
  • Appearance of any new lesion
• No history of brain metastases or current treated or untreated brain metastases

PATIENT CHARACTERISTICS:

• WHO performance status 0-2
• Able to understand the nature of the trial
• No unstable or severe concurrent medical conditions
• No active uncontrolled infection

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• Recovered from prior systemic therapy and other previously administered investigational agents

• No prior radiotherapy or chemotherapy for metastatic disease

  • Prior neoadjuvant and adjuvant chemotherapy allowed
• May have received one prior systemic non-chemotherapeutic treatment (i.e., immunotherapy, receptor tyrosine kinase inhibitor, antiangiogenic agent, or differentiating agent) for recurrent or metastatic disease
• More than 2 years since prior adjuvant therapy before androgen deprivation therapy for metastatic disease AND patient must remain hormone-sensitive
• Sufficient time must have elapsed since other prior investigational agents to ensure that drug interactions do not occur during this study
• No history of orchiectomy
• Concurrent androgen deprivation therapy for metastatic disease allowed
• Concurrent bisphosphonates allowed at the discretion of the treating physician
• No other concurrent investigational agents