The Impact of Resection Margin Status and Postoperative CA19-9 Levels on Survival and Patterns of Recurrence After Postoperative High-Dose Radiotherapy With 5-FU—Based Concurrent Chemotherapy for Resectable Pancreatic Cancer

Abstract

To analyze the impact of surgical margins and other clinicopathological data on treatment outcomes on 75 patients treated from 1999 to 2006 by initial potentially curative surgery (+/- intraoperative radiotherapy), followed by high-dose 3-dimensional conformal radiation therapy and concomitant fluoropyrimidine-based chemoradiotherapy. All clinical and pathologic data on this patient cohort were analyzed by actuarial Kaplan-Meier survival methodology and by univariate and multivariate Cox proportional hazards methods to measure effects on survival and patterns of failure. With a median follow-up of 28 months, the median, 2-year and 5-year overall survival (OS) rates were 18.1 month, 41% and 23.6%, respectively. Disease-free survival (DFS) rates were of 11.4 months, 35% and 20%, respectively. Only 2 clinicopathological features, positive (< or =1 mm) surgical margins (P < 0.05) and a 2-fold (>70 U/mL) elevation of the postoperative serum CA19-9 (P < 0.001) impacted OS and disease-free survival. In patients with negative (>1 mm) surgical margins and a low (< or =70 U/mL) postoperative CA19-9, the projected 2- and 5-year OS were 80% and 65%, respectively, compared with 40% and 10% with positive surgical margins and a low CA19-9 and to 10% and 0% with positive or negative surgical margins and a high (>70 U/mL) CA19-9. Positive surgical margins (P < 0.001) and an elevated postoperative CA19-9 (P < 0.001) also predicted early development of distant metastases, whereas isolated loco-regional failure was less common and not affected by these or other clinicopathological features. Using this fluoropyrimidine-based chemoradiotherapy regimen after surgical resection (+/- intraoperative radiotherapy), positive surgical margins and an elevated (2-fold) postoperative serum CA19-9 level predicted for reduced survival and early development of distant metastatic disease.