Dalteparin and Radiation Therapy in Treating Patients With Newly Diagnosed Supratentorial Glioblastoma Multiforme

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