Oblimersen and Dacarbazine in Treating Patients With Advanced Malignant Melanoma That Has Responded to Treatment on Clinical Trial GENTA-GM301

DISEASE CHARACTERISTICS: Histologically confirmed advanced malignant melanoma Unresectable or metastatic disease Previously enrolled on GENTA-GM301 protocol Complete or partial objective response or stable disease after completion of 8 courses of oblimersen (G3139) and dacarbazine on arm II of GENTA-GM301 Measurable or evaluable disease No uncontrolled brain metastases or leptomeningeal disease PATIENT CHARACTERISTICS: Age Any age Performance status ECOG 0-2 Life expectancy Not specified Hematopoietic Absolute neutrophil count at least 1,500/mm^3* Platelet count at least 100,000/mm^3* Hemoglobin at least 8 g/dL* NOTE: *Hematopoietic growth factor or transfusion independent Hepatic Bilirubin no greater than 1.5 times upper limit of normal (ULN) AST and ALT no greater than 2.5 times ULN Alkaline phosphatase no greater than 2.5 times ULN Albumin at least 2.5 g/dL PTT no greater than 1.5 times ULN PT no greater than 1.5 times ULN OR INR no greater than 1.3 No history of chronic hepatitis or cirrhosis Renal Creatinine no greater than 1.5 times ULN OR Creatinine clearance at least 50 mL/min Cardiovascular No uncontrolled congestive heart failure No active symptoms of coronary artery disease, defined as uncontrolled arrhythmias or recurrent chest pain despite prophylactic medication No New York Heart Association class III or IV heart disease No cardiovascular signs and symptoms grade 2 or greater within the past 4 weeks Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception No other significant medical disease No uncontrolled seizure disorder No active infection No uncontrolled diabetes mellitus No active autoimmune disease No known hypersensitivity to phosphorothioate-containing oligonucleotides or dacarbazine No intolerance to prior oblimersen and dacarbazine, including discontinuation of protocol therapy due to 1 or more adverse events HIV negative Satisfactory venous access for a 5-day continuous infusion Intellectually, emotionally, and physically able to maintain an ambulatory infusion pump PRIOR CONCURRENT THERAPY: Biologic therapy At least 4 weeks since prior biologic therapy, immunotherapy, cytokine therapy, or vaccine therapy and recovered No concurrent anticancer biologic therapy Chemotherapy See Disease Characteristics No other concurrent anticancer chemotherapy Endocrine therapy No concurrent chronic corticosteroids (average dose of at least 20 mg/day of prednisone or equivalent) Radiotherapy At least 4 weeks since prior radiotherapy and recovered No concurrent anticancer radiotherapy Surgery At least 4 weeks since prior major surgery and recovered Other At least 4 weeks since other prior therapy and recovered More than 3 weeks since prior experimental therapy (except for GENTA-GM301 protocol) No intervening systemic therapy for melanoma since completion of GENTA-GM301 protocol therapy No other concurrent anticancer therapy, including investigational therapy No concurrent immunosuppressive drugs No concurrent anticoagulation therapy Concurrent warfarin (1 mg/day) for central line prophylaxis is allowed