Phase II trials of retinol in patients with advanced cancer

We have completed a phase II trial of oral retinol (200,000 units/m²) in 65 patients with advanced cancer. All patients were followed at 4-week intervals for tumor response and clinical or chemical evidence of toxicity. Seventeen patients had non-small cell lung cancer, 15 had melanoma, 12 had adenocarcinoma of the colon, and 17 had miscellaneous tumors. There were one partial response, five mixed responses, two patients with stable disease, and 47 patients with progressive disease. Thirty-seven of 60 patients reported no side effects; 13 developed mild cutaneous symptoms; and 12 developed reversible central nervous system symptomatology. Oral retinol appears to have limited activity in patients with advanced cancer.