Objectives
The purpose of this study was to determine the relationship between carbohydrate antigen (CA) 19‐9 levels and outcome in patients with borderline resectable pancreatic cancer treated with neoadjuvant therapy (NT).
Methods
This study included all patients with borderline resectable pancreatic cancer, a serum CA 19‐9 level of ≥40 U/ml and bilirubin of ≤2 mg/dl, in whom NT was initiated at one institution between 2001 and 2010. The study evaluated the associations between pre‐ and post‐NT CA 19‐9, resection and overall survival.
Results
Among 141 eligible patients, CA 19‐9 declined during NT in 116. Following NT, 84 of 141 (60%) patients underwent resection. For post‐NT resection, the positive predictive value of a decline and the negative predictive value of an increase in CA 19‐9 were 70% and 88%, respectively. The normalization of CA 19‐9 (post‐NT <40 U/ml) was associated with longer median overall survival among both non‐resected (15 months versus 11 months; P = 0.022) and resected (38 months versus 26 months; P = 0.020) patients. Factors independently associated with shorter overall survival were no resection [hazard ratio (HR) 3.86, P < 0.001] and failure to normalize CA 19‐9 (HR 2.13, P = 0.001).
Conclusions
The serum CA 19‐9 level represents a dynamic preoperative marker of tumour biology and response to NT, and provides prognostic information in both non‐resected and resected patients with borderline resectable pancreatic cancer.