Abstract 1222P
Background
Even after neoadjuvant chemoradiotherapy and surgery, esophageal cancer frequently relapses, with limited prognostic prospects. The present study evaluates the impact of the tumor regression Mandard score on recurrence patterns and survival.
Methods
This nationwide cohort study included patients treated with neoadjuvant chemoradiotherapy and esophagectomy for distal esophageal or gastroesophageal junction adenocarcinoma in 2007-2016 (follow up until January 2020). Patients with unknown recurrence status or tumor regression status were excluded. Tumor regression status were postoperatively determined by experienced gastro-intestinal pathologists. Chi-square tests and survival analyses with log-rank tests were performed across groups with different tumor regression statuses.
Results
Among all 2746 patients included in this study, 47% developed recurrence. Complete response to neoadjuvant chemoradiotherapy (TRG1) was observed in 22%. The recurrence rate increases by increasing Mandard score (TRG1 vs. TRG2,3,4, and 5: 30.6% vs. 44.9%, 52.9%, 61.4%, and 58.2%, p<0.001). Although non-significant, TRG1 patients tend to proportionately develop less locoregional and more distant recurrences than TRG>1 patients. In TRG1 patients, significantly more brain recurrence ratio (p 0.001), less omentum/peritoneum (p 0.025), less locoregional abdominal lymph node recurrence ratio (p 0.013), prolonged time to recurrence (median 12 vs. 10 months, p 0.019) and improved OS (mean 44 vs. 35 months, p<0.001) were observed compared to TRG>1 patients.
Conclusions
After neoadjuvant chemoradiotherapy and surgery for esophageal adenocarcinoma, Mandard score seems to be predictive of the locations of recurrent disease. Complete regression is associated with prolonged time to recurrence and improved survival compared to TRG>1. It is advisable to include Mandard score into decision making for postoperative surveillance and therapy.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The IVORY study Group.
Funding
Has not received any funding.
Disclosure
M.F. Bijlsma: Non-Financial Interests, Personal, Advisory Role: Servier; Financial Interests, Institutional, Research Grant: Celgene, Lead Pharmacy . H.W.M. van Laarhoven: Financial Interests, Institutional, Advisory Board: BMS, MSD; Financial Interests, Personal, Invited Speaker: Lilly; Financial Interests, Institutional, Invited Speaker: Nordic Pharma, Servier; Financial Interests, Institutional, Research Grant, REPEAT study: Bayer; Financial Interests, Institutional, Research Grant: BMS, Philips; Financial Interests, Institutional, Invited Speaker, FRACTION study: BMS; Financial Interests, Institutional, Research Grant, ACTION study: Celgene; Financial Interests, Institutional, Research Grant, DECO study: Janssen; Financial Interests, Institutional, Invited Speaker, RAINFALL study: Lilly; Financial Interests, Institutional, Invited Speaker, KEYNOTE 062 and KEYNOTE 181 study: Merck/MSD; Financial Interests, Institutional, Research Grant, SOX study: Nordic Pharma; Financial Interests, Institutional, Research Grant, TRAP study, PERFECT study; local PI of JACOB study: Roche; Financial Interests, Institutional, Research Grant, LyRICX study: Servier; Financial Interests, Institutional, Research Grant, TAPESTRY study: Merck; Financial Interests, Institutional, Research Grant, Research money and investigational product: Incyte; Non-Financial Interests, Institutional, Product Samples, For all clinical study mentioned, study medication is provided: See 'research funding'. M.I. van Berge Henegouwen: Financial Interests, Personal, Advisory Role: Mylan, Alesi Surgical, Medtronic, Johnson and Johnson; Financial Interests, Institutional, Research Grant: Olympus, Stryker . All other authors have declared no conflicts of interest.