DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed diagnosis of 1 of the following malignancies:

  • Stage III or IV sarcoma, including:

    • Leiomyosarcoma
    • Synovial cell sarcoma
    • Liposarcoma
    • Gastrointestinal stromal tumor

  • Brain tumor, including:

    • Diffuse pontine glioma*
    • Glioblastoma multiforme
    • Glialsarcoma NOTE: *For patients with diffuse pontine glioma, the requirement for histologic verification may be waived
• No known curative therapy
• HLA A*0201 positive by genotyping

PATIENT CHARACTERISTICS:

Age

• Over 2

Performance status

• Karnofsky 60-100% (patients over age 16)
• Lansky 60-100% (patients under age 16)

Life expectancy

• Not specified

Hematopoietic

• WBC greater than 3,000/mm^3
• Absolute neutrophil count greater than 1,500/mm^3
• Platelet count greater than 100,000/mm^3

Hepatic

• AST and ALT less than 2.5 times upper limit of normal (ULN)
• Bilirubin less than 1.5 times ULN

Renal

• Creatinine less than 1.5 times ULN

Cardiovascular

• No clinically significant cardiovascular disease

Pulmonary

• No clinically significant pulmonary disease

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior hematopoietic stem cell transplantation
• No other concurrent vaccine therapy
• No other concurrent immunotherapy

Chemotherapy

• No prior chemotherapy
• No concurrent chemotherapy

Endocrine therapy

• Concurrent dexamethasone allowed provided patient has been on a decreasing dose for the past 2 weeks and the current dose is the lowest clinically acceptable dose (ideally, less than 9-12 mg/day)

Radiotherapy

• No prior extensive-field radiotherapy that would compromise bone marrow function
• At least 2 weeks since prior local radiotherapy

Surgery

• At least 2 weeks since prior surgery

Other

• At least 2 weeks since prior imatinib mesylate
• No concurrent local anesthetic to administration site of vaccine