Postresection CA 19-9 predicts overall survival in patients with pancreatic cancer treated with adjuvant chemoradiation: a prospective validation by RTOG 9704

J Clin Oncol. 2008 Dec 20;26(36):5918-22. doi: 10.1200/JCO.2008.18.6288. Epub 2008 Nov 24.

Abstract

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 (< 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.

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 < 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.

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.

Publication types

  • Clinical Trial, Phase III
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers, Tumor / blood*
  • CA-19-9 Antigen / blood*
  • Chemotherapy, Adjuvant
  • Combined Modality Therapy
  • Female
  • Humans
  • Lewis Blood Group Antigens / blood
  • Male
  • Middle Aged
  • Pancreatic Neoplasms / mortality*
  • Pancreatic Neoplasms / surgery
  • Pancreatic Neoplasms / therapy*
  • Prognosis
  • Radiotherapy, Adjuvant

Substances

  • Biomarkers, Tumor
  • CA-19-9 Antigen
  • Lewis Blood Group Antigens