Clinical significance of CA 19-9 elevation during postoperative surveillance for extrahepatic bile duct cancer: a nomogram-based approach for the prediction of short-term recurrence

Abstract

BackgroundThis study aimed to assess the significance of elevated carbohydrate antigen (CA) 19-9 in postoperative surveillance of extrahepatic bile duct cancer and to identify short-term recurrence predictors. MethodsThis retrospective study included patients with elevated CA 19-9 post-curative surgery. Patients were categorized into positive and negative CT groups based on the detection of recurrence at CA 19-9 elevation. Short-term recurrence was defined as recurrence within 6 months in the negative CT group. We identified the factors associated with short-term recurrence and devised a predictive nomogram. ResultsAmong the 190 patients, 91 (47.9%) exhibited tumor recurrence with CA 19-9 elevation (CT-positive group), whereas 99 (52.1%) showed no recurrence (CT-negative group). In the CT-negative group (n=99), 22 (22.2%) experienced short-term tumor recurrence within 6 months. Preoperative CA 19-9 (odds ratio [OR]: 1.5, p=0.016), postoperative CA 19-9 (OR: 1.9, p=0.047), adjuvant treatment (OR: 3.5, p=0.032), and the absence of inflammation (OR: 3.5, p=0.045) were predictors of short-term recurrence. The area under the curve of the nomogram was 0.80 (95% CI: 0.69–0.90). DiscussionDespite elevated CA 19-9 levels, approximately 50% of patients exhibited no recurrence during postoperative surveillance for extrahepatic bile duct cancer. Factors influencing short-term recurrence encompass pre- and postoperative CA 19-9, adjuvant treatment, and inflammatory status.