Multicenter Selective Lymphadenectomy Trial (MSLT)

Inclusion Criteria: 1. The patient consents to be in the study. 2. The patient must have invasive melanoma with: 1) Clark Level III and Breslow Thickness greater than or equal to 1.00 mm; or 2) Clark Level IV or V with any Breslow thickness. A confirmation of diagnosis and thickness must be made by the institutional pathologist. 3. The primary cutaneous melanoma site must be on the head, neck, trunk, extremity, scalp, palm of the hand, sole of the foot, or subungual skin. 4. The patient's biopsy must have been completed no more than 10 weeks before the initial visit to the clinic. (Surgery must be scheduled within three months of the biopsy.) 5. The patient must be between 18 and 75 years old. 6. The patient must have a life expectancy of at least 10 years from the time of diagnosis, excluding the diagnosis of melanoma. Exclusion Criteria: 1. The patient had a prior wide excision of the primary with a diameter of excision greater than or equal to 3.0 cm and the shortest margin from the tumor edge to the excision edge was measured by a pathologist to be greater than or equal to 1.5 cm; or the patient had an elliptical excision and a margin beyond the tumor edge was greater than or equal to 1.5 cm at the narrowest margin. 2. The primary cutaneous melanoma involves the eye, ear, mucous membranes. 3. The patient has clinical evidence of satellite lesions, in-transit, regional nodal or distant metastases. 4. The patient has a second primary invasive melanoma. 5. The patient has had any type of solid tumor or hematologic malignancy during the past 5 years. Exceptions are if the patient has been treated for T1 lesions (e.g., squamous cell carcinoma of the skin, basal cell carcinoma or in situ carcinoma of the uterine cervix) during the past 5 years, but has not received treatment within the last 6 months. 6. The patient has had prior skin grafts, tissue transfers or flaps, or lymph node dissections that may alter the lymphatic drainage pattern from a primary cutaneous melanoma to the adjacent regional lymph node basins. 7. The patient has had previous chemotherapy, immunotherapy or radiation therapy. 8. The patient has had an organ transplantation and is receiving immunosuppressive agents as a result of the transplantation. 9. The patient has taken oral or parenteral steroids or immunosuppressive drugs within the last 6 months. 10. The patient has any known primary or secondary immune deficiencies. 11. The patient has another medical condition that will affect life expectancy. 12. The patient is pregnant. 13. Evidence that the patient cannot undergo selective lymph node dissection for any reason.