Colonic lymphoid follicles associated with colonic neoplasms.

In 3,399 patients more than 40 years of age undergoing air-contrast enema examinations a prospective evaluation was done for the presence of colonic lymphoid follicles. In 3,315 patients there was no evidence of lymphoid follicles. Colonic neoplasms were diagnosed in 8.47% of these individuals. Eighty-four patients were found to have radiographically identifiable follicles. Fifty-eight of these 84 patients (69%) with lymphoid follicles had a synchronous (n = 19) or previous (n = 14) colonic neoplasm or a synchronous (n = 24) or previous (n = 1) colonic polyp. There were no consistent clinical or radiographic features that distinguished the patients with and without a neoplastic association. However, 90% of men with lymphoid follicles had associated neoplasms, whereas only 58% of women did. Because of the frequent association, detection of colonic lymphoid follicles in patients in this age group should lead to a vigorous search for subtle colonic neoplasms that may not be apparent because of technical limitations of the study.