Changes in the nutritional status of nine vitamins in patients with esophageal cancer during chemotherapy.

Background: Many studies have investigated the relationships between vitamins and esophageal cancer (EC). Most of these studies focused on the roles of vitamins in the prevention and treatment of EC, and few studies have examined the changes in vitamin nutritional status and their influencing factors before and after chemotherapy for EC. Chemotherapy may have a considerable effect on EC patients' vitamin levels and hematological indicators.