Aim: This prospective cohort study aimed to evaluate the etiology of elevated CA 19-9 levels and to present appropriate guidelines for the asymptomatic patients. Methods: Between January 2004 and March 2007, we enrolled consecutive asymptomatic patients who had elevated CA 19-9 levels >37 U/mL. To evaluate the etiology, the CA 19-9 level was rechecked and further studies were carried out. If the CA 19-9 level decreased to the normal range, or if it showed a decreasing trend, then it was monitored annually. Yet, if the CA 19-9 level showed an increasing trend, then the level was monitored at intervals of 1, 3, and 6 months until no evidence of malignancy was proven. Results: Of the 62,976 patients, 501 (0.8%) subjects showed an elevated CA 19-9 level. This prospective analysis was conducted on 353 subjects (70.5%) who were followed up for at least 6 months. Ten patients (2.8%) were diagnosed with malignancies. There were 97 patients (27.5%) with benign diseases and 246 patients (69.7%) were deemed non-specific. Conclusions: CA 19-9 should not be used as a screening tool. In the case of a persistently elevated CA 19-9 level, further work-up for determining the etiology should be done. © 2009 Editrice Gastroenterologica Italiana S.r.l.
Kim, B. J., Lee, K. T., Moon, T. G., Kang, P., Lee, J. K., Kim, J. J., & Rhee, J. C. (2009). How do we interpret an elevated carbohydrate antigen 19-9 level in asymptomatic subjects? Digestive and Liver Disease, 41(5), 364–369. https://doi.org/10.1016/j.dld.2008.12.094