Based on the high response rates seen among patients with colon cancer receiving high dose Melphalan with autologous marrow infusion, the Southwest Oncology Group conducted a Phase II trial of the compound at a conventional dose. The initial starting dose of 40 mg/m2 was reduced to 30 mg/m2 after severe myelotoxicity was encountered in the first five patients. Toxicity was primarily myeloid and was moderate to severe in most patients with one treatment related death. There were two complete and one partial response among 43 patients. Melphalan at 30 mg/m2 has little activity among patients with metastatic colorectal carcinoma.