Predictive Value of Elevated CA 19-9 for Positive Resection Margins after Pancreaticoduodenectomy for Pancreatic Tumors

Abstract

Introduction: Elevated Carbohydrate antigen (CA) 19-9 levels have predicted poor prognosis and decreased survivals after pancreaticoduodenectomy for pancreatic head carcinoma. This study analyzes the predictive value of elevated CA 19-9 for positive resection margin in these cases. Material and methods: Retrospective analysis of prospectively entered data from 2011 to 2019 revealed 202 cases at our specialized hepatopancreatobiliary centre. Demographic details, imaging findings, liver function tests and pre-operative tumor markers were recorded. Histopathology data regarding tumor and nodal status and resection margins were recorded as per Leeds protocol. Positive margins were considered as < 1mm from the tumor. Results: 106 of 202 (52.4%) patients had CA 19-9 >100 U/mL (Normal: < 37 U/mL) in absence of jaundice. 63 (31.2%) patients had node positive disease, and 78 (38.6%) had lymphovascular/perineural invasion. Retroperitoneal (SMA) margin was positive in 16 (15.1%) patients with elevated CA 19-9 and 4 (4.1%) patients with normal CA 19-9. SMV margin was positive in 38 (35.8%) patients with elevated CA 19-9 and 11 (11.4%) patients with normal CA 19-9. Pancreatic ductal margin was positive in 3 (3.1%) patients with elevated Ca 19-9. 57 (53.7%) patients with elevated CA 19-9 and 15 (15.6%) patients with normal Ca 19-9 had positive margins. This difference is statistically significant (p< 0.05) using student's t-test. Conclusion: Elevated CA 19-9 level is a strong predictor of margin positivity after pancreaticoduodenectomy irrespective of T stage. These cases may be better suited for neoadjuvant therapy and needs evaluation in a prospective study.OP04-22Histopathology and margin status in pancreaticoduodenectomyParameterCA 19-9 >100 U/mLCA 19-9 <100 U/mLp-valueNumber of patients106 (52.4%)96 (47.5%)N+ disease63 (31.2%)21 (10.3%)<0.05*Median LN ratio0.33±0.260.14±0.12<0.05*LVI/PNI78 (38.6%)35 (17.3%)<0.05*Positive SMA margin16 (15.1%)4 (4.1%)<0.05*Positive SMV margin38 (35.8%)11 (11.4%)<0.05*Positive duct margin3 (3.1%)0Positive margin status57 (53.7%)15 (15.6%)<0.05* Open table in a new tab