DISEASE CHARACTERISTICS:

• Histologically confirmed adenocarcinoma of the prostate

  • Any T, any N, M0

• Received prior therapy comprising one of the following regimens for primary prostate cancer:

  • External beam radiotherapy
  • Brachytherapy with or without pelvic external beam radiotherapy
  • Cryosurgery

  • Radical prostatectomy with or without adjuvant or salvage radiotherapy

    • Adjuvant or salvage radiotherapy after radical prostatectomy is allowed provided the following criteria is met:

      • PSA was never greater than 6.0 ng/mL
      • At least 3 months since androgen deprivation
• Elevated PSA (0.4-6.0 ng/mL) that has increased on 2 measurements taken at least 2 weeks apart
• No history of or radiological evidence of current CNS disease (e.g., primary brain tumor, seizures not controlled with standard medical therapy, or brain metastases)

PATIENT CHARACTERISTICS:

Age:

• Not specified

Performance status:

• ECOG 0-1

Life expectancy:

• At least 12 months

Hematopoietic:

• WBC greater than 2,500/mm^3
• Absolute neutrophil count greater than 1,000/mm^3
• Platelet count greater than 100,000/mm^3
• No prior bleeding disorder

Hepatic:

• Bilirubin no greater than 2 times upper limit of normal (ULN)
• AST no greater than 2 times ULN
• Hepatitis B and C negative

Renal:

• Creatinine no greater than 2 times ULN
• BUN no greater than 2 times ULN

Cardiovascular:

• No clinically significant cardiovascular disease
• No New York Heart Association grade II-IV heart disease (symptomatic congestive heart failure)
• No unstable angina pectoris
• No serious cardiac arrhythmia requiring medication
• No uncontrolled hypertension
• No prior myocardial infarction
• No grade II or greater peripheral vascular disease within the past year
• No prior deep vein thrombosis

Other:

• Fertile patients must use effective contraception
• HIV and HTLV I and II negative
• No other uncontrolled illness, underlying medical condition, psychiatric illness, or social situation that would preclude study participation
• No ongoing or active infection
• No active autoimmune disease requiring treatment
• No significant traumatic injury within the past 4 weeks
• No serious nonhealing wound, ulcer, or bone fracture

• No other "currently active" malignancy except nonmelanoma skin cancer

  • Not "currently active" if considered by physician as having less than 30% risk of relapse after completion of therapy

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior immunotherapy
• No prior anti-vascular endothelial growth factor therapy

Chemotherapy:

• No prior chemotherapy

Endocrine therapy:

• See Disease Characteristics
• No prior hormonal therapy (e.g., luteinizing hormone-releasing hormone [LHRH] agonists or antagonists, antiandrogens, estrogens, megestrol, or PC-SPES) for progressive disease
• Prior hormonal therapy in adjuvant or neoadjuvant setting as primary therapy allowed if at least 3 months since androgen deprivation
• No concurrent systemic steroid therapy (inhaled or topical steroids allowed)

Radiotherapy:

• See Disease Characteristics
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics
• At least 4 weeks since prior major surgery, including open biopsy or needle biopsy of liver
• No concurrent major surgery

Other:

• At least 10 days since prior aspirin
• At least 10 days since prior oral or parenteral anticoagulants except to maintain patency of pre-existing permanent indwelling IV catheters
• No concurrent aspirin
• No concurrent oral or parenteral anticoagulants except to maintain patency of pre-existing permanent indwelling IV catheters
• No other concurrent experimental or commercial agents or therapies for prostate cancer