Potassium depletion and malignant transformation of villous adenomas of the colon and rectum.

Epidemiologic evidence suggests that a high potassium intake inhibits the development of cancer, and a high sodium intake increases the incidence of gastrointestinal malignancy. Once malignant transformation occurs the sodium/potassium ratio in the cancer cell increases to more than three times that of a normal cell. The ionic redistribution seen in the cancer cell is similar to that seen in the potassium-depleted state. The relationship between potassium depletion and the size at which villous adenomas of the large bowel undergo malignant transformation was examined in 144 patients. Villous adenomas containing invasive carcinoma were 40% smaller in potassium-depleted patients than in normal patients indicating that in the potassium-depleted state earlier malignant transformation had occurred.