Isoflavone in Prostate-specific Antigen Recurrent Prostate Cancer

Phase II Trial of Isoflavone in Prostate-specific Antigen Recurrent Prostate Cancer After Previous Local Therapy.

Primary Outcome Measures:

Decrease in rate of serum PSA rise

Secondary Outcome Measures:

Adherence to treatment regimens

Quality of life as assessed by FACT-P at baseline and at 12 months of treatment

Modulation of serum testosterone,isoflavone metabolites, and cholesterol

Estimated Enrollment: 27 Study Start Date: November 2003 Estimated Primary Completion Date: February 2007 (Final data collection date for primary outcome measure)

• Pretreatment evaluation included a complete medical history, physical examination (including digital rectal examination), serum PSA, free/total testosterone, lipids, serum isoflavone levels (genistein, daidzein, and equol), and assessment of quality of life (Functional Assessment of Cancer Treatment-Prostate, FACT-P questionnaire).
• Whole blood will be obtained prior to initiation of the study to assess for DNA polymorphism.
• Follow-up serum PSA levels to assess efficacy were obtained at 3, 6, 9, and 12 months after initiation of treatment.
• Medical history, physical examination, serum testosterone, lipids, isoflavone, and quality of life were assessed at 6 and 12 months after initiation of treatment.

Inclusion Criteria:

• Raising serum PSA profile after previous definitive therapy (e.g., radical prostatectomy or external beam radiation therapy).
• Life expectancy of at least one year and performance status of <2 of Zubrod scale.

Exclusion Criteria:

• Metastatic or locally recurrent disease demonstrated on bone scan, computed tomography or transrectal ultrasound, or be clinically symptomatic at the time of enrollment
• No androgen deprivation therapy (ADT) or chemotherapy within 12 months of entry into the study.
• Known allergic reaction to milk or soy products were excluded.