DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed newly diagnosed supratentorial glioblastoma multiforme

• At least 2 weeks but no more than 4 weeks since prior surgery

  • Patients with biopsy only must be at least 1 week past surgery

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• ECOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Platelet count at least 100,000/mm^3
• No history of heparin-induced thrombocytopenia
• No coagulopathy

Hepatic:

• Bilirubin no greater than 2.5 mg/dL
• AST no greater than 3 times upper limit of normal (ULN)
• PT/aPTT no greater than 1.5 times ULN

Renal:

• Creatinine no greater than 2.0 mg/dL
• No gross hematuria within the past 6 months

Cardiovascular:

• No uncontrolled hypertension
• No unstable angina
• No symptomatic congestive heart failure
• No myocardial infarction within the past 6 months
• No uncontrolled cardiac arrhythmia

Gastrointestinal:

• No peptic ulcer disease within the past 6 months

• Negative stool guaiac

  • Negative endoscopy required if positive stool guaiac

Other:

• No known hypersensitivity to dalteparin, heparin, or pork products
• No CNS trauma within the past 3 months
• No intracranial or intraocular hemorrhage, unless related to surgery, within the past 6 months
• No retinal detachment within the past 6 months
• No other concurrent malignancy receiving treatment
• No active infection
• No AIDS-related illness
• HIV negative
• Must weigh at least 90 pounds (40 kg)
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No concurrent immunomodulators
• No concurrent investigational matrix metalloproteinase inhibitors or antiangiogenesis agents

Chemotherapy:

• Prior chemotherapy for other malignancy allowed
• No concurrent standard or investigational cytotoxic chemotherapy

Endocrine therapy:

• Not specified

Radiotherapy:

• No prior cranial irradiation
• Prior radiotherapy for other malignancy allowed
• Concurrent radiotherapy allowed

Surgery:

• See Disease Characteristics
• Recovered from prior surgery
• No prior eye or ear surgery

Other:

• No concurrent nonsteroidal anti-inflammatory drugs
• No ongoing or concurrent aspirin or anticoagulation therapy except routine central venous catheter flushing
• No other concurrent non-protocol therapy