RATIONALE: Interferon alfa may interfere with the growth of the cancer cells. It is not yet known if this treatment is more effective than observation following surgery for stage III melanoma.

PURPOSE: Randomized phase III trial to determine the effectiveness of interferon alfa in treating patients who have undergone surgery for stage III melanoma.

OBJECTIVES:

• Compare the effect of adjuvant therapy with pegylated interferon alfa vs observation, in terms of distant metastases-free survival, in patients with previously resected stage III melanoma.
• Compare the overall survival in these patients after treatment with pegylated interferon alfa vs observation.
• Determine the toxicity of pegylated interferon alfa in these patients.
• Determine the compliance of these patients treated with pegylated interferon alfa.
• Compare the quality of life in these patients after treatment with pegylated interferon alfa vs observation.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to type of nodal involvement (N1 vs N2), number of positive nodes (1 vs 2-4 vs 5 or more vs not assessed), Breslow primary (T1-2 vs T3 vs T4 vs unknown), ulceration of primary tumor (absent vs present vs unknown), sex, and center. Patients are randomized to one of two treatment arms.

• Arm I: Patients receive pegylated interferon alfa subcutaneously weekly for 5 years.
• Arm II: Patients undergo observation only. Treatment continues in the absence of distant metastases or unacceptable toxicity.

Quality of life is assessed at baseline, and then at months 3, 12, 24, 36, 48, and 60.

Patients are followed every 6 months for 5 years.

PROJECTED ACCRUAL: A total of 1,200 patients (600 per treatment arm) will be accrued for this study within 1.5-2 years.

DISEASE CHARACTERISTICS:

• Histologically confirmed previously resected stage III primary cutaneous melanoma or unknown primary with regional lymph node involvement

  • N1 disease

    • Microscopic, nonpalpable nodal involvement
    • Primary melanoma of any stage with clinically inapparent N1 regional lymph node metastases (T1-4, N1, M0) detected by elective lymph node dissection or sentinel node biopsy

  • N2 disease

    • Palpable nodal involvement with synchronous primary melanoma or apparent nodal disease after prior excision (any pT, N2, M0)

  • Regional lymph node recurrence at any interval after surgery for primary melanoma of any depth (T1-4, rN2, M0)

• Complete resection of primary melanoma with adequate surgical margins

• Full lymphadenectomy must be performed within 70 days of study

• No mucous membrane melanoma or ocular melanoma

• No evidence of distant or nonregional lymph node metastases or in transit metastases (even if previously resected)

• No incompletely resected disease due to gross extracapsular extension

PATIENT CHARACTERISTICS:

Age:

• 18 to 70

Performance status:

• ECOG 0-1

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 3,000/mm^3
• Platelet count greater than 100,000/mm^3
• Hemoglobin at least 9 g/dL

Hepatic:

• SGOT and SGPT less than 2 times upper limit of normal
• No active hepatitis

Renal:

• Creatinine less than 2.0 mg/dL

Cardiovascular:

• No severe cardiovascular disease including the following:

  • Arrhythmias requiring chronic treatment
  • Congestive heart failure (New York Heart Association class III or IV)
  • Symptomatic ischemic heart disease

Other:

• No other prior malignancy within the past 5 years except surgically cured nonmelanomatous skin cancer or carcinoma in situ of the cervix
• No thyroid dysfunction unresponsive to therapy
• No uncontrolled diabetes mellitus
• No active autoimmune disease
• No active and/or uncontrolled infection
• No history of neuropsychiatric disorder requiring hospitalization
• No known active alcohol or drug abuse
• HIV negative
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• No prior interferon alfa
• No prior immunotherapy for melanoma
• No other concurrent immunologic or biologic therapy
• No concurrent colony stimulating factors including epoetin alfa and filgrastim (G-CSF)

Chemotherapy:

• No prior chemotherapy for melanoma
• No concurrent chemotherapy

Endocrine therapy:

• No prior hormonal therapy for melanoma
• No concurrent hormonal therapy
• No concurrent chronic systemic corticosteroid therapy

Radiotherapy:

• No prior radiotherapy for melanoma
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics
• Recovered from any prior recent surgery

Other:

• At least 30 days since other prior experimental therapy
• No other concurrent investigational drugs