MRI in Assessing Hypoxia in Patients With Localized Prostate Cancer Undergoing Stereotactic Body Radiation Therapy

Hypoxia Assessment in Localized Prostate Cancer: A Companion Protocol to a Phase II Study of Stereotactic Body Radiation Therapy (SBRT) for Low and Intermediate Risk Prostate Cancer

RATIONALE: Diagnostic procedures, such as MRI, may help measure oxygen levels in tumor cells. It may also help doctors predict a patient's response to treatment and help plan the best treatment.

PURPOSE: This clinical trial is studying how well MRI works in assessing hypoxia in patients with localized prostate cancer undergoing stereotactic body radiation therapy.

OBJECTIVES:

• To characterize the status of global hypoxia within the prostate before stereotactic body radiotherapy (SBRT) as assessed by blood-oxygen-level-dependent and tissue-oxygen-level-dependent MRI.
• To characterize tumor vasculature and metabolism within the prostate before SBRT as assessed by dynamic contrast-enhanced MRI and magnetic resonance spectroscopic imaging, respectively.
• Correlate prostate and normal tissue hypoxia before SBRT with clinical outcomes (toxicity and biochemical [PSA] control) after SBRT.

OUTLINE: Within 1-3 weeks before beginning stereotactic body radiotherapy, patients undergo T2-weighted anatomic MRI, magnetic resonance spectroscopic imaging, blood-oxygen-level-dependent and tissue-oxygen-level-dependent MRI, and dynamic contrast-enhanced MRI.

DISEASE CHARACTERISTICS:

• Biopsy proven adenocarcinoma of the prostate

  • Localized disease

• Scheduled to undergo treatment with stereotactic body radiotherapy (SBRT) on a phase II clinical trial

  • Has not yet started SBRT

PATIENT CHARACTERISTICS:

• Serum creatinine ≤ 1.2 mg/dL
• No claustrophobia
• No other contraindication to MRI (e.g., implanted pacemaker device)
• No known allergy to MRI contrast

PRIOR CONCURRENT THERAPY:

• No prior treatment for prostate cancer (e.g., hormonal therapy or chemotherapy)