Vaccine Therapy With or Without Cyclophosphamide in Treating Patients Who Have Undergone Surgery for Stage II, Stage III, or Stage IV Melanoma

RATIONALE: Vaccines made from peptides may help the body build an effective immune response to kill tumor cells. Drugs used in chemotherapy, such as cyclophosphamide, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Cyclophosphamide may also stimulate the immune system in different ways and stop tumor cells from growing. Giving vaccine therapy together with cyclophosphamide after surgery may cause a stronger immune response to kill any remaining tumor cells. It may also prevent or delay the recurrence of melanoma. PURPOSE: This randomized phase I/II trial is studying the side effects of vaccine therapy when given with or without cyclophosphamide and to see how well they work in treating patients who have undergone surgery for stage II, stage III, or stage IV melanoma.