466. ESOPHAGECTOMY AFTER NEOADJUVANT CHEMORADIATION THERAPY: DOES THE TIMING OF SURGERY INFLUENCE THE OUTCOME?

Abstract

Abstract Background Multimodality treatment, either neoadjuvant chemoradiotherapy (nCRT) or perioperative chemotherapy (e.g., FLOT), and surgery, represents the standard of care for locally advanced, resectable cancer of the esophagus and esophago-gastric junction. The recommended interval between the ending of nCRT and surgery is between 6 and 8 weeks. A prolonged time to surgery (TTS) is associated with an increase in pathologic complete response (pCR) and survival in different malignancies, with a possible increase in surgical difficulty and postoperative complications. Materials and methods: A retrospective analysis was conducted on 154 patients with cT2-4aN0-(+), cT1bN+, M0 squamous cell (SCC) and adenocarcinoma (AC) cancer of the esophagus and esophagogastric junction (Siewert type 1) treated with nCRT and surgery between August 2017 and January 2022. Three groups were identified: patients operated within 10 (n = 37), between 10 and 12 (n = 48) and beyond 12 weeks (n = 69). Minimum follow-up period was six months. Results Demographic and clinical characteristics were comparable. Mean length of stay was 13.1, 15.6 and 16.5 days (p = 0.06) respectively. Incidence of postoperative complications and their severity were not different between groups. No postoperative deaths were observed. No difference in pCR was found. When analyzed by histology, a slight increase was evident in patients with SCC (33.3%, 43.5%, 39.4%; vs ADC 16%, 16%, 16.7%), though not statistically significant. Similar results were obtained for tumor regression grade, with an increase in major responses for SCC over time (Mandard 1–2: SCC 50%, 61%, 62%; ADC 60%, 64%, 58%). No difference in overall survival was observed. Conclusions Esophagectomy performed more than 10 weeks after the end of chemoradiation therapy was not associated with an increase in postoperative morbidity. We observed, though, a trend towards longer hospital stays. The rate of major pathological response seems to increase over time after completion of chemoradiation therapy, but only for squamous histotype. Larger studies are required to corroborate these findings.