Changes in DNA After Radiation Therapy in Patients With Prostate Cancer

OBJECTIVES:

Primary

• Demonstrate the feasibility of acquiring specimens, both frozen and paraffin-embedded, to yield RNA of adequate quality to perform DNA microarray studies on markers of radiotherapy outcome in patients with intermediate-risk prostate cancer.

Secondary

• Compare the gene expression results from frozen tissue and paraffin-embedded tissue to see the correlation between the 2 methods in patients treated on the brachytherapy alone arm of protocol RTOG-0232.
• Find genes that are expressed differentially before and after radiation therapy in patients treated on the brachytherapy plus external-beam radiation therapy arm of protocol RTOG-0232.
• Find gene expression patterns in patients treated on either arm of protocol RTOG-0232 who have significant associations with biochemically as well as clinically apparent local and distant failure.

OUTLINE: This is a multicenter, pilot study.

Frozen and paraffin-embedded tissue samples are studied for biomarker/laboratory analysis. DNA microarray analysis is performed on the samples to assess markers of radiotherapy outcome.

PROJECTED ACCRUAL: A total of 156 patients will be accrued for this study.

Inclusion criteria

• Histologically confirmed, locally confined adenocarcinoma of the prostate
• Zubrod performance 0-1
• Clinical stages T1c - T2b, N0, M0
• Combined Gleason score 7 if prostate specific antigen (PSA) < 10, combined Gleason score < 7 if PSA 10 - 20; PSA must be ≤ 20 ng/mL, before hormone therapy, if given, and a prostate volume by transrectal ultrasound (TRUS) ≤ 60 cc.
• American Urological Association (AUA) score ≤ 15 (alpha blockers are allowed).
• Age ≥ 18 years old and must sign a study-specific informed consent form

Exclusion criteria

• No clinically or pathologically involved lymph nodes
• No distant metastases or significant obstructive symptoms
• No prior chemotherapy, pelvic radiation, transurethral prostatectomy (TURP), cryosurgery, TUNA, transurethral microwave thermotherapy (TUMT) or radical surgery for carcinoma of the prostate is allowed.
• No previous hormonal therapy beginning < 2 months or > 6 months prior to registration is allowed.
• No previous or concurrent cancers other than basal, in situ, or squamous cell skin cancers unless the patient is disease free for ≥ 5 years.
• No hip prosthesis or major medical or psychiatric illnesses are allowed. prior to study entry.