Carcinoembryonic antigen in patients suffering from ulcerative proctocolitis.

Carcinoembryonic antigen (CEA) has been measured by radioimmunoassay in samples obtained from all patients suffering from ulcerative proctocolitis and seen within a four-month period. The characteristics of this group of patients have been compared with reported epidemiological studies in this disease, and have been found to have a similar sex ratio and age of onset, but a more limited disease. Among 59 patients, 11 were found to have elevated circulating CEA values. One of the 11 had a colonic carcinoma and another was pregnant. Excluding these two patients, an overall prevalence of elevated CEA levels of 17.5% was found. The prevelance in ulcerative proctitis was 7.1%, and in colitis was 19.9%. The patients in whom elelvated plasma CEA values were found were compared with the remaining patients in relation to factors known to be associated with an increased propensity for the development of colorectal carcinoma complicating ulcerative colitis. There was no difference in mean age of the patients at disease onset, nor was there any difference in disease duration, extent, and control. A significant correlation was found between elevated plasma CEA levels and the severity of the initial attack. One patient with premalignant changes in the rectal mucosa had consistently normal concentrations of plasma CEA. There was no significant correlation between elevated plasma CEA values and disease activity. The mean age of the two groups of patients was similar. No carcinoma has manifested in any patient during follow-up periods of at least 18 months.