Serum CA19-9 alterations during preoperative gemcitabine-based chemoradiation therapy for resectable invasive ductal carcinoma of the pancreas as an indicator for therapeutic selection and survival.

OBJECTIVE: To evaluate serum CA19-9 alterations during preoperative gemcitabine-based chemoradiation therapy (CRT) for resectable pancreatic cancer (PC) in the earlier identification of patients who are likely to benefit from subsequent resection. SUMMARY BACKGROUND DATA: One of the advantages of the preoperative CRT strategy for patients with advanced PC is that undetectable systemic disease may be revealed during preoperative CRT, thus avoiding unnecessary surgery. Serum CA19-9 has been evaluated as a predictive indicator of the treatment efficacy and outcome in various clinical settings.
METHODS: We retrospectively reviewed 64 consecutive patients with resectable PC (at diagnosis) who received preoperative CRT at our hospital between 2002 and 2008. Patients were divided into 2 groups (efficacy grouping) to evaluate the efficacy of preoperative CRT according to the clinical course. Group A included patients who were unable to receive the subsequent resection due to the development of unresectable factors during preoperative CRT and those who received the subsequent resection but developed recurrent disease within 6 months after surgery; group B included patients who received the subsequent resection and survived without recurrences for more than 6 months after surgery. We developed a new classification utilizing pretreatment CA19-9 and proportional alteration of CA19-9 2 months after the initiation of treatment. The categories were defined as: I (increased), MD (modestly decreased), and SD (substantially decreased). Clinicopathological variables and CA19-9 alteration status were correlated with the efficacy grouping and overall survival.
RESULTS: All of the category I patients were included in group A, 93.5% of the category SD patients in group B, and approximately half of the category MD patients in group A. CA19-9 alteration status was a single independent variable associated with efficacy grouping and overall patient survival, with the 1-year survival rate of category I patients, and the 4-year survival rate of category MD and SD patients being 22.2%, 34.1%, and 58.9%, respectively.
CONCLUSIONS: CA19-9 alteration status is useful in identifying those who will benefit from the preoperative CRT and subsequent resection and those who will not; it was a significant predictor for patient prognosis in the setting of the preoperative CRT strategy for resectable PC.