Effect of Riboflavin-fortified Salt Nutrition Intervention on Esophageal Squamous Cell Carcinoma in a High Incidence Area, China

Background: Riboflavin-fortified salt is now supplied in the diet for residents who live in high incidenceareas for esophageal squamous cell carcinoma in China. Patients and
Methods: All residents from 21 townshipsin Cixian, Hebei province were divided into an intervention group (9 townships, 11,382 people) who took upriboflavin-fortified salt and a control group (12 townships, 10,711 people) who were free from riboflavin-fortifiedsalt. Some 1,300 of the control group and 950 of the intervention group were randomly selected to undergoendoscopy examination using iodine dying with multi-point biopsy and histopathology examination. Amongthem 155 of the intervention group and 120 of the control group were tested for the blood riboflavin level withrefernce to the erythrocyte glutathione reductase activity coefficient (EGRAC). Esophageal squamous cellcarcinoma incidence data were further obtained from the Cixian Cancer Registry.
Results: The results ofendoscopy suggested the mucosal status of the intervention group to be better than that of the control group. Itshowed 82.1% of the mucosal status of control group to be normal, 14.8% to have dysplasia, and 3.1% precanceror cancer, respectively, as compared to 84.8%, 13.6% and 1.6%, respectively, for the intervention group.The mean EGRAC values for the intervention and control groups were 1.452 and 1.606, respectively (P<0.01);compared with normal mucous membrane of esophagus, the lack of riboflavin increased the risk of esophagealsquamous cell carcinoma (OR=3.921, 95%CI =1.853~11.936), but the risk of dysplasia did not increase (OR=3.421,95%CI=0.912-10.159); after intervention, the six years average esophageal squamous cell carcinoma incidenceof the intervention group (112.46/100,000) was lower than in the control group (142.11/100,000), although therewas no statistical significance (u=1.858, P>0.05).
Conclusion: It proved practical and effective to improve thestatus of riboflavin and esophageal mucosa by taking up riboflavin-fortified salt.