Clinical trial NCT00031746: Soy Protein Supplement in Preventing Prostate Cancer in Patients With Elevated Prostate-Specific Antigen Levels
Official title: Effects of Dietary Soy on Biomarkers of Prostate Cancer: A Prospective Phase II Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
Conditions: Prostate Cancer
Keywords: prostate cancer
Lead sponsor: Alliance for Clinical Trials in Oncology
Sponsor class: OTHER
Collaborators: name: National Cancer Institute (NCI)
First posted: 2003-01-27
Enrollment: 26
Sex: MALE
Minimum age (years): 50
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: RATIONALE: Soy protein supplement may prevent or delay the development of prostate cancer in patients who have elevated prostate-specific antigen (PSA) levels.

PURPOSE: Randomized phase II trial to determine the effectiveness of soy protein supplement in preventing prostate cancer in patients who have elevated PSA levels.

Detailed description: OBJECTIVES:

* Compare the reduction in the rate of prostatic cellular proliferation in patients with an elevated PSA (5 to 10 ng/mL) and a negative biopsy for prostate cancer when treated with daily soy protein supplements vs placebo.
* Compare the effect of these regimens on additional biomarkers of prostate cancer (PSA, high-grade prostate intraepithelial neoplasia, induction of apoptosis, sex steroid receptor expression, and loss of glutathione S-transferase-pi) in these patients.
* Compare the effect of these regimens on quality of life, including urinary and sexual function, in these patients.

OUTLINE: This is a randomized, double-blind, placebo-controlled, multicenter study. Patients are stratified according to race (Caucasian vs African American). After 2 weeks of daily oral placebo, patients are randomized to 1 of 2 arms.

* Arm I: Patients receive oral soy protein supplement daily for 12 months.
* Arm II: Patients receive oral placebo daily for 12 months. Quality of life is assessed at baseline and at 6 and 12 months.

PROJECTED ACCRUAL: A total of 160 patients (80 per arm) will be accrued for this study within 12 months.

Eligibility criteria: DISEASE CHARACTERISTICS:

* Histologically confirmed absence of prostate cancer

  * Atypical adenomatous hyperplasia or prostatic intraepithelial neoplasia (high-grade or low-grade) allowed
  * Abnormal baseline transrectal ultrasound and digital rectal exam allowed
  * Biopsy may be before or after study entry, but must be within the past 90 days
* PSA 5-10 ng/mL

PATIENT CHARACTERISTICS:

Age:

* 50 and over

Performance status:

* ECOG 0-2

Life expectancy:

* Not specified

Hematopoietic:

* Not specified

Hepatic:

* Not specified

Renal:

* Not specified

Other:

* No known allergy to soy protein or milk protein
* No invasive cancer within the past 5 years except non-melanoma skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* Not specified

Endocrine therapy:

* No prior hormonal therapy
* No prior finasteride
* No concurrent hormonal therapy
* No concurrent finasteride

Radiotherapy:

* Not specified

Surgery:

* At least 6 months since prior transurethral resection of the prostate
* No prior orchiectomy
* No concurrent orchiectomy

Other:

* No other concurrent soy products

Primary outcomes:
measure: Reduction of prostatic cellular proliferation rates by 50% as measured by Ki-67
timeFrame: 12 months
Secondary outcomes:
Other outcomes:
Locations:
city: Washington
country: United States
facility: Walter Reed Army Medical Center
state: District of Columbia
city: Syracuse
country: United States
facility: CCOP - Hematology-Oncology Associates of Central New York
state: New York
city: Syracuse
country: United States
facility: Community General Hospital of Greater Syracuse
state: New York
city: Winston-Salem
country: United States
facility: Wake Forest University Comprehensive Cancer Center
state: North Carolina
city: Columbus
country: United States
facility: Arthur G. James Cancer Hospital and Solove Research Institute at Ohio State University
state: Ohio
Study officials:
affiliation: Roswell Park Cancer Institute
name: James L. Mohler, MD
role: STUDY_CHAIR
References: