Postresection CA 19-9 Predicts Overall Survival in Patients With Pancreatic Cancer Treated With Adjuvant Chemoradiation: A Prospective Validation by RTOG 9704

• Published in: Journal of clinical oncology Vol. 26; no. 36; pp. 5918 - 5922
• Main Authors: BERGER, Adam C, GARCIA, Miguel, HOFFMAN, John P, REGINE, William F, ABRAMS, Ross A, SAFRAN, Howard, KONSKI, Andre, BENSON, Alan B, MACDONALD, John, WILLETT, Christopher G
• Format: Journal Article
• Language: English
• Published: Alexandria, VA American Society of Clinical Oncology 20-12-2008
• Subjects: Adult; Aged; Aged, 80 and over; Biological and medical sciences; Biomarkers, Tumor - blood; CA-19-9 Antigen - blood; Chemotherapy, Adjuvant; Combined Modality Therapy; Female; Gastroenterology. Liver. Pancreas. Abdomen; Gastrointestinal Cancer; Humans; Lewis Blood-Group System - blood; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Middle Aged; Pancreatic Neoplasms - mortality; Pancreatic Neoplasms - surgery; Pancreatic Neoplasms - therapy; Prognosis; Radiotherapy, Adjuvant; Tumors; Human; Validation; Malignant tumor; Radiotherapy; Survival; Prospective; Chemotherapy; Treatment; Cancerology; Pancreas cancer; Digestive diseases; Combined treatment; Predictive factor; Antigen CA 19 9; Cancer; Pancreatic disease
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/JCO.2008.18.6288

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.
CA 19-9 expression was analyzed as a dichotomized variable (< 180 v > or = 180) or (< or = 90 v > 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.
Three hundred eighty-five patients patients had assessable CA 19-9 levels. The majority had a CA 19-9 level lower than 180 or < 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 < or = 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.
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.