Omega-3 Fatty Acids in Treating Patients With Advanced Cancer Who Have Significant Weight Loss

DISEASE CHARACTERISTICS: * Histologically or cytologically proven advanced cancer not amenable to curative therapy (solid tumors and hematologic malignancies eligible except primary and metastatic brain tumors) * Cachexia (weight loss at least 2 percent within a one month period) PATIENT CHARACTERISTICS: Age: * 18 and over Performance Status: * CALBG 0-2 Life Expectancy: * At least 2 months Hematopoietic: * Granulocytes greater than 1,000/mm3 * Platelet count greater than 75,000/mm3 * Hemoglobin greater than 8 mg/dL Hepatic: * AST less than 3 times upper limit of normal (ULN) * Alkaline phosphatase less than 3 times ULN * Bilirubin less than 1.5 times ULN Renal: * BUN less than 1.5 times ULN * Creatinine less than 1.5 times ULN Cardiovascular: * No congestive heart failure requiring diuretics within less than 6 months * No uncontrolled or severe cardiovascular disease within less than 6 months * No myocardial infarction within less than 6 months Other: * Not pregnant nor contemplating pregnancy during study * Negative pregnancy test * No uncontrolled hypercalcemia * No metabolic disorders (hyperthyroidism) * No poorly controlled diabetes * No peripheral edema or ascites requiring diuretics * No enteric fistulas, with tracheobronchial fistulas or with aspiration * No esophageal or bowel obstruction that would preclude eating * Free T4 within normal range * No serious medical illness * No psychosis * No uncontrolled bacterial, viral, or fungal infections * No active uncontrolled duodenal ulcers * Above laboratory values required unless bone marrow, liver, kidney, or splenic involvement by tumor is documented PRIOR CONCURRENT THERAPY: Biologic therapy: * Not specified Chemotherapy: * Prior and concurrent chemotherapy allowed Endocrine therapy: * No concurrent steroids such as dronabinol or megestrol acetate (except for adrenal failure) Radiotherapy: * No prior or concurrent radiotherapy to abdomen or pelvis Surgery: * Greater than 3 weeks since major surgery * Greater than 1 week since minor surgery Other: * No concurrent diuretics