Isoflavones and Radiation Therapy in Treating Patients With Localized Prostate Cancer

Barbara Ann Karmanos Cancer Institute

Status and phase: Completed; Phase 2

Conditions: Prostate Cancer

Treatments: Radiation: radiation therapy; Dietary Supplement: soy protein isolate

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT00243048

P30CA022453 (U.S. NIH Grant/Contract)

CDR0000446088

WSU-D-2325

Details and patient eligibility

About

RATIONALE: Eating a diet high in soy foods may slow the progression of some types of cancer. Isoflavones are compounds found in soy food that may slow the growth of prostate cancer cells and prevent further development of prostate cancer. Radiation therapy uses high-energy x-rays to kill tumor cells. Giving isoflavones together with radiation therapy may be an effective treatment for prostate cancer.

PURPOSE: This randomized phase II trial is studying the side effects and how well giving isoflavones together with radiation therapy works in treating patients with localized prostate cancer.

Full description

OBJECTIVES:

• Determine the effect of soy protein isolate (isoflavones) and radiotherapy on the modulation of biomarkers in patients with localized prostate cancer.
• Determine the toxicity of this regimen in these patients.
• Determine the effect of this regimen on the quality of life of these patients.

OUTLINE: This is a randomized, placebo-controlled study. Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients receive oral soy protein isolate (isoflavones) twice daily for 6 months in the absence of disease progression or unacceptable toxicity.
• Arm II: Patients receive an oral placebo twice daily for 6 months in the absence of disease progression or unacceptable toxicity.

In both arms, patients also undergo radiotherapy while receiving isoflavones or placebo.

Quality of life is assessed periodically.

PROJECTED ACCRUAL: A total of 70 patients will be accrued for this study.

Enrollment: 70 estimated patients

Sex: Male

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate that is localized to the prostate gland
• Must be scheduled to receive curative radiotherapy for prostate cancer
• Not eligible for a higher priority study at the Karmanos Cancer Institute

PATIENT CHARACTERISTICS:

Performance status

• 0-3

Life expectancy

• Not specified

Hematopoietic

• Not specified

Hepatic

• Not specified

Renal

• Not specified

Other

• No organ function restrictions

PRIOR CONCURRENT THERAPY:

Chemotherapy

• No prior chemotherapy

Endocrine therapy

• No prior hormonal therapy

Radiotherapy

• See Disease Characteristics

Other

• No other concurrent micronutrient supplements, herbs, or vitamins except 1 daily multivitamin