A. Rich1, E. Ward1, M. Aldakkak1, B. George1, M. Kamgar1, W. Hall1, B. Erickson1, D. B. Evans1, S. Tsai1 1Medical College of Wisconsin, Department Of Surgical Oncology, Milwaukee, WISCONSIN, USA
Introduction: Carcinoembryonic antigen (CEA) is a biomarker that is infrequently measured in patients with pancreatic cancer. Previous research has explored the prognostic impact of CEA in patients with advanced disease, but the prognostic impact of CEA in patients with localized disease receiving neoadjuvant therapy is not well understood.
Methods: Patients with resectable or borderline resectable pancreatic cancer treated with neoadjuvant therapy from 2009-2021 were identified from a prospectively maintained database. CEA values were measured at diagnosis (Dx) and preoperative (preop) restaging. Patients that were missing values at either timepoint were excluded. CEA was classified as either elevated or normal based on the laboratory upper limit of normal (4.7 ng/mL).
Results: Of the 534 patients identified, CEA at Dx was found to be elevated in 171 (32%) and normal in 363 (68%). Preop CEA was elevated in 114 (21%) and normal in 420 (79%). Of the 171 patients with elevated CEA at Dx that received neoadjuvant therapy, preop CEA levels normalized in 83 (49%) and remained elevated in 88 (51%). Of these 171 patients, an elevated preop CEA was negatively associated with completion of neoadjuvant therapy and surgery in a multivariable logistic regression model (OR 0.18; 95% CI 0.09 – 0.38; p < 0.001). The median overall survival (mOS) for all 534 patients was 27 months. The mOS for the 363 patients with normal CEA at Dx was 31 months and 22 months for the 171 patients with elevated CEA at Dx (p = 0.0001). Of the 171 patients with elevated CEA at Dx, the mOS for the 83 patients with normal preop CEA values was 26.5 months and 17 months for the 88 patients with elevated preop CEA values (p = 0.002; Figure 1). Among the 171 patients with an elevated CEA at Dx, in an adjusted proportional hazards model elevated preop CEA was associated with a 1.90-fold (95% CI 1.30 – 2.79; p = 0.001) increased risk of death.
Conclusion: Patients with an increased CEA at Dx who failed to normalize preop CEA had reduced odds of completing neoadjuvant therapy and surgery and had decreased mOS. This suggests CEA is an informative prognostic biomarker in patients with localized pancreatic cancer and longitudinal monitoring during neoadjuvant treatment may be beneficial.
