Interleukin-21 in Treating Patients With Metastatic or Recurrent Malignant Melanoma

DISEASE CHARACTERISTICS: * Histologically confirmed cutaneous malignant melanoma * Recurrent or metastatic disease that is not curable by surgical or other means * Clinically and/or radiologically documented disease defined as at least one site of disease unidimensionally measurable ≥ 20 mm by x-ray, physical exam, or nonspiral CT scan OR ≥ 10 mm by spiral CT scan * Must have nonbulky metastatic disease defined as the largest measurable lesion ≤ 50 mm in maximum diameter * Must have primary diagnosis tumor tissue or previously resected metastatic melanoma tissue available (i.e., paraffin block or unstained slides) * No known brain metastases PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Life expectancy ≥ 12 weeks * Absolute granulocytes count ≥ 1,500/mm\^3 * Platelet count ≥ 100,000/mm\^3 * Bilirubin normal * Serum creatinine ≤ 1.5 times upper limit of normal (ULN) * AST and ALT ≤ 2.5 times ULN * Negative pregnancy test * Not pregnant or nursing * Fertile patients must use effective contraception during study therapy * No uncontrolled intercurrent illness or condition including, but not limited to, any of the following: * Ongoing or active infection * Symptomatic congestive heart failure * Unstable angina pectoris * Cardiac arrhythmia * Psychiatric illness or social situation that would limit compliance with study requirements * No history of hemolysis or a hemolytic disorder including, but not limited to, any of the following: * Sickle cell anemia * Thalassemia * Autoimmune hemolytic anemia * No history of other malignancies within the past 5 years except adequately treated nonmelanoma skin cancer, curatively treated carcinoma in situ of the cervix, or other solid tumors curatively treated with no evidence of disease * No known HIV, hepatitis B, or hepatitis C infection * Patients must reside within a 2-hour drive from a participating center PRIOR CONCURRENT THERAPY: * No previous systemic therapy for metastatic disease * At least 3 months since prior adjuvant immunotherapy for recurrent melanoma * No prior immunotherapy for metastatic disease * No prior immunotherapy outside the adjuvant setting * At least 4 weeks since prior major surgery * At least 4 weeks since prior radiotherapy except low-dose, nonmyelosuppressive radiotherapy and recovered * More than 4 weeks since prior and no concurrent investigational agents or anticancer therapy * No prior chemotherapy including regional therapy * No concurrent systemic corticosteroids (e.g., prednisone or dexamethasone) * Concurrent topical steroids are allowed