DISEASE CHARACTERISTICS:

• Histologically confirmed primary or metastatic soft tissue sarcoma or bone sarcoma at high risk of recurrence

  • Grade III-IV tumor greater than 8 cm
  • Grade III-IV primary tumor greater than 5 cm with positive surgical margins
  • Grade III-IV primary tumor greater than 5 cm with distant metastases resected within 1 year of primary surgery
• No more than 8 weeks since prior surgical resection of primary or metastatic disease
• Ineligible for other high priority national or institutional study

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• SWOG 0-2

Life expectancy:

• More than 2 months

Hematopoietic:

• WBC greater than 3,000/mm^3
• Neutrophil count at least 1,500/mm^3
• Platelet count greater than 70,000/mm^3
• Hemoglobin at least 10.0 g/dL

Hepatic:

• Bilirubin less than 2.0 mg/dL
• SGOT or SGPT less than 3 times upper limit of normal (ULN)*
• Alkaline phosphatase less than 3 times ULN*
• No decompensated liver disease
• No autoimmune hepatitis
• No coagulation disorders NOTE: * Unless due to metastatic disease

Renal:

• Creatinine normal

Cardiovascular:

• No history of severely debilitating cardiovascular disease
• No unstable angina
• No uncontrolled congestive heart failure
• No thrombophlebitis

Pulmonary:

• No history of severely debilitating pulmonary disease
• No chronic obstructive pulmonary disease
• No pulmonary embolism

Other:

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use 2 forms of effective contraception for 4 weeks before, during, and for 4 weeks after study
• No acute infection requiring systemic antibiotics
• No prior hypersensitivity to interferon alfa or any component of the injection
• No diabetes mellitus prone to ketoacidosis
• No severe myelosuppression
• No history of autoimmune disease
• No pre-existing thyroid abnormalities with thyroid function that cannot be maintained in the normal range
• No clinically significant retinal abnormalities
• No other serious medical or psychiatric illness that would preclude study
• No prior malignancy except curatively treated carcinoma in situ of the cervix or skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• Prior systemic chemotherapy allowed

Endocrine therapy:

• Not specified

Radiotherapy:

• Prior radiotherapy allowed

Surgery:

• See Disease Characteristics