Intensity Modulated Radiation Therapy with Stereotactic Radiosurgery Boost and Hormone Therapy in Treating Patients with Prostate Cancer

Inclusion Criteria

• Pathologically (histologically or cytologically) proven diagnosis of prostatic adenocarcinoma within 180 days of registration at moderate to high risk for recurrence as determined by one of the following combinations: * Gleason score 7-10 + T1c-T3 (palpation) + prostate specific antigen (PSA) < 75 ng/ml (includes intermediate and high risk patients) * Gleason score 6 + T2c-T3 (palpation) or > 50% (positive) biopsies + PSA < 75 ng/ml * Gleason score 6 + T1c-T2b (palpation) + PSA > 20 ng/ml
• History/physical examination (to include at a minimum digital rectal examination of the prostate and examination of the skeletal system and abdomen) within 90 days prior to registration
• Clinically negative lymph nodes as established by imaging (pelvic ± abdominal computed tomography [CT] or magnetic resonance imaging [MRI]), (but not by nodal sampling, or dissection) within 90 days prior to registration
• Patients with lymph nodes equivocal or questionable by imaging are eligible if the nodes are =< 2.0 cm
• No evidence of bone metastases (M0) on bone scan within 90 days prior to registration
• Equivocal bone scan findings are allowed if plain films (or CT or MRI) are negative for metastasis
• Baseline serum PSA value performed with an Food and Drug Administration (FDA)-approved assay (e.g., Abbott, Hybritech) within 12 weeks (90 days) prior to registration
• Study entry PSA should not be obtained during the following time frames: (1) 10-day period following prostate biopsy; (2) following initiation of hormonal therapy; (3) within 30 days after discontinuation of finasteride; (4) within 90 days after discontinuation of dutasteride
• Zubrod performance status 0-2
• Absolute neutrophil count (ANC) >= 1,500 cells/mm^3 (obtained within 2 weeks [14 days] prior to registration on study)
• Platelets >= 100,000 cells/mm^3 (obtained within 2 weeks [14 days] prior to registration on study)
• Hemoglobin >= 8.0 g/dl (Note: the use of transfusion or other intervention to achieve hemoglobin [Hgb] >= 8.0 g/dl is acceptable) (obtained within 2 weeks [14 days] prior to registration on study)
• Patient must be able to provide study specific informed consent prior to study entry

Exclusion Criteria

• Grade T4 prostatic adenocarcinoma
• Prior invasive (except non-melanoma skin cancer) malignancy unless disease-free for a minimum of 2 years
• Previous radical surgery (prostatectomy) or cryosurgery for prostate cancer
• Previous pelvic irradiation, prostate brachytherapy, or bilateral orchiectomy
• Previous hormonal therapy, such as luteinizing hormone-releasing hormone (LHRH) agonists (e.g., leuprolide, goserelin, buserelin, triptorelin) or LHRH antagonist (e.g. degarelix), anti-androgens (e.g., flutamide, bicalutamide, cyproterone acetate), estrogens (e.g., diethylstilbestrol [DES]), or surgical castration (orchiectomy)
• Prior pharmacologic androgen ablation for prostate cancer is allowed only if the onset of androgen ablation is =< 90 days prior to the date of registration
• Use of finasteride within 30 days prior to registration
• Use of dutasteride or dutasteride/tamsulosin (Jalyn) within 90 days prior to registration
• Previous or concurrent cytotoxic chemotherapy for prostate cancer; note that prior chemotherapy for a different cancer is allowable
• Prior radiotherapy, including brachytherapy, to the region of the study cancer that would result in overlap of radiation therapy fields
• Severe, active co-morbidity, defined as follows: * Unstable angina and/or congestive heart failure requiring hospitalization within the last 6 months * Transmural myocardial infarction within the last 6 months * Acute bacterial or fungal infection requiring intravenous antibiotics at the time of registration * Hepatic insufficiency resulting in clinical jaundice and/or alanine aminotransferase (ALT) or aspartate aminotransferase (AST) > 2 x upper limit of normal
• Patients who are sexually active and not willing/able to use medically acceptable forms of contraception; this exclusion is necessary because the treatment involved in this study may be significantly teratogenic
• Prior allergic reaction to the hormones involved in this protocol
• Patients status-post a negative lymph node dissection are not eligible