DISEASE CHARACTERISTICS:

• Histologically confirmed diagnosis of one the following:

  • Stage II-IV gastric cancer

  • Stage IIC-IV ovarian cancer in first complete remission

    • CA 125 normal and stable*
  • Grade III anaplastic astrocytoma

  • Stage IV (M1) prostate adenocarcinoma

    • No small cell variations

    • No biochemical progression after definitive surgery, defined by the following:

      • Prostate-specific antigen more than 0.4 ng/mL which remains elevated on 2 additional measurements at least 2 weeks apart after prostatectomy
      • Three consecutive rises in PSA, each at least 1 month apart after definitive radiotherapy
    • Must be receiving androgen blockade
    • PSA less than 5 ng/mL and stable*
• Documented EGFRvIII expression in primary tumor
• Must have received prior surgery and or chemoradiotherapy for disease (except prostate cancer patients) NOTE: *Stable defined as no increase over 2 measurements at least 28 days apart with the last measurement within the past 28 days

PATIENT CHARACTERISTICS:

Age:

• 80 and under

Performance status:

• Zubrod 0

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 3,000/mm^3
• Platelet count at least 100,000/mm^3
• Hemoglobin at least 10 g/dL

Hepatic:

• SGOT no greater than 2.5 times upper limit of normal (ULN)
• Alkaline phosphatase no greater than 2.5 times ULN
• No hepatitis

Renal:

• Not specified

Other:

• No other malignancy in the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or adequately treated stage I or II cancer in complete remission
• No contraindication to receiving sargramostim (GM-CSF) or KLH-based vaccine products
• No autoimmune disease
• HIV negative
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• See Disease Characteristics
• At least 1 month since prior cytotoxic chemotherapy
• No concurrent chemotherapy

Endocrine therapy:

• See Disease Characteristics
• At least 1 month since prior treatment dose corticosteroids
• No concurrent corticosteroids

Radiotherapy:

• See Disease Characteristics
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics

Other:

• Recovered from all prior therapies
• No concurrent enrollment on other phase I studies
• No other concurrent immune modulators