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