Abstract

INTRODUCTION

The primary aim of this study is to evaluate and define locoregional recurrence regions individually matching with radiotherapy (RT) plans in gastric adenocarcinoma patients treated with curative surgery and adjuvant chemoradiotherapy (CRT). The secondary aim is to present the survival results.

METHODS

62 adult gastric adenocarcinoma patients who underwent curative resection and received adjuvant CRT at two radiation oncology centers were analyzed. The 4500-5040 cGy was delivered in 25-28 fractions. At follow-up, computed tomography, which described recurrence, was transferred to the RT planning system and defined the site of relapse according to RT isodose curves.

RESULTS

The median follow up time was 18 months, 22 patients (35%) have been relapsed. Five patients had isolated loco-regional failure. Three of these relapses were in the RT field, one was marginal recurrence and the remaining one was outside the RT field. Two nodal recurrence regions were covered by 95% and 100% isodose lines and the other nodal recurrence region was covered by 20% isodose line with respect to their initial radiotherapy volumes. One local recurrence was in the anastomosis site covered by 90% isodose line and the other was on the peritoneal surface covered by 50% isodose line. The 3 and 5-year overall survival (OS) were 71% and 55% respectively, and were better with D2 lymph node dissection without statistical significance.

DISCUSSION AND CONCLUSION

Identification of the local recurrence site may be helpful in determining the RT target volume. For this, controlled studies with more patients are needed.