Radiation dose mapping and anastomotic complications after trimodality therapy for esophageal cancers

Background and purpose: There is conflicting evidence with respect to the correlation between neoadjuvant chemoradiation and anastomotic complications following trimodality therapy in patients with esophageal cancer. We aimed to analyze the relationship between their dosimetry and any resulting anastomotic complications. Materials and methods: The medical records of 51 consecutive patients who underwent trimodality therapy between 2007 and 2014 were retrospectively reviewed. We analyzed the differences in the mean dose received by regions of the esophagus relative to the landmark of the azygous vein and the stomach to correlate the development of an anastomotic complication using nonparametric rank-sum tests. Results: Anastomotic leakage and stricture rates were 12% and 22%, respectively. Patients with anastomotic complications received a statistically significant higher mean dose to the esophagus at the level of the azygous vein (0.0 cm) and lower (up to -2.7 cm) (28.4-42.2 Gy vs. 10.3-27.6 Gy, p < 0.04). There were no differences noted in mean gastric doses. Median follow up time was 30.9 months. Median overall survival and disease free survival of our patient cohort was 34.4 months and 22.5 months, respectively. The development of an anastomotic complication did not affect survival outcomes. Conclusion: Patients who experienced anastomotic complication after trimodality therapy for esophageal cancer were more likely to have received a higher mean esophageal dose around the proximity of the azygous vein, where intrathoracic anastomoses most commonly occur. Communication between surgical and radiation oncologists regarding the anastomotic location may be an important consideration in planning for trimodality therapy in reducing potential anastomotic complications. (C) 2019 The Authors. Published by Elsevier B.V. on behalf of European Society for Radiotherapy and Oncology.