Originally published as JCO Early Release 10.1200/JCO.2008.18.6288 on November 24 2008


Journal of Clinical Oncology, Vol 26, No 36 (December 20), 2008: pp. 5918-5922
© 2008 American Society of Clinical Oncology.
Postresection CA 19-9 Predicts Overall Survival in Patients With Pancreatic Cancer Treated With Adjuvant Chemoradiation: A Prospective Validation by RTOG 9704

Adam C. Berger, Miguel Garcia, Jr, John P. Hoffman, William F. Regine, Ross A. Abrams, Howard Safran, Andre Konski, Alan B. Benson, III, John MacDonald, Christopher G. Willett

From the Thomas Jefferson University; Radiation Therapy Oncology Group; Fox Chase Cancer Center, Philadelphia, PA; University of Maryland Medical Center, Baltimore, MD; Rush University School of Medicine; Northwestern University, Chicago, IL; Brown University, Providence, RI; Aptium Oncology, New York, NY; and Duke University, Durham, NC

Corresponding author: Adam C. Berger, MD, FACS, 1100 Walnut St, Medical Office Building, Suite 500, Philadelphia, PA 19147; e-mail: adam.berger@jefferson.edu

Purpose: CA 19-9 is an important tumor marker in patients with pancreatic adenocarcinoma. A secondary end point of Radiation Therapy Oncology Group trial 9704 was prospective evaluation of the ability of postresectional CA 19-9 to predict survival.

Methods: CA 19-9 expression was analyzed as a dichotomized variable (<> 90). Cox proportional hazards models were utilized to identify the impact of CA 19-9 expression on overall survival (OS). Actuarial estimates for OS were calculated using Kaplan-Meier methods.

Results: Three hundred eighty-five patients patients had assessable CA 19-9 levels. The majority had a CA 19-9 level lower than 180 or 90 (n = 220 and 200, respectively), while 34% were Lewis Antigen negative and 33 (9%) and 53 (14%) patients had levels higher than 180 and higher than 90. When CA 19-9 was analyzed as a dichotomized variable, there was a significant survival difference favoring patients with CA 19-9 lower than 180 (hazard ratio [HR], 3.53; P < .0001). This corresponds to a 72% reduction in the risk of death for patients with a CA 19-9 lower than 180. This was also true for patients with CA 19-9 90 (HR, 3.4; P < .0001). Multivariate analyses confirmed that CA 19-9, when analyzed as both a continuous and a dichotomized variable, is a highly significant predictor of OS in patients with resected pancreatic cancer.

Conclusion: To our knowledge, this is the first phase III trial to perform prospective analysis of CA 19-9 levels in patients treated with adjuvant chemoradiotherapy. It definitively confirms the prognostic importance of postresectional CA 19-9 levels after surgery with curative intent in patients with pancreatic cancer.

published online ahead of print at www.jco.org on November 24, 2009.