Abstract 1401P
Background
GEJ and gastric ADC have a biologic resemblances, and therapy could be similar. Incidence esophageal ADC is increasing. Gastric ADC is decreasing, but its absolute number is increasing. EUS is still considered a controversial restaging tool (difficulties to distinguish residual primary tumor, radiation effects and fibrosis). Clinicians rely more on PET-CT or CT, and sometimes avoid EUS.This work compares the accuracy of EUS and PET-CT in restaging esophageal and gastric ADC.
Methods
We created a database containing gastric and esophagic ADC patients from ‘Virgen de las Nieves’ University Hospital who underwent a gastrectomy or esophagectomy after neoadjuvant therapy (2010-2019). Our routine evaluation included a restaging EUS and PET-CT after neoadjuvant thepapy. Pathologic staging and follow-up visits were recorded. Descriptive statistics were performed. Overall agreement between EUS and Pathologic staging was assessed with kappa statistic. Kaplan-Meier for survival analysis. Differential survival by pathologic T status and by restaging EUS T status with LogRank Test. Analyses were made in SPSS25 (IBM).
Results
188 patients:131 gastric ADC (58.5%), 15 lower esophageal ADC (6.7%) and 41 GEJ ADC (18.3%). EUS T restaging showed 36.8% T4 stage, 35.3% T3, 7.1% T2 and 1.3%T1. For N restaging: 23.2% N1, 23.2% N2, 1.4% N3 and 52.2% N0. Poor agreement between restaging EUS and pathologic T status (kappa=0.187).Restaging EUS accurately predicted the pathologic T status in only 37%. Lymph node: EUS accurately detected N+ with a moderate agreement with pathologic results (kappa=0.530), better than PET-CT (kappa=0.165). Restaging EUS accurately predicted N+ in 77% of patients. Survival: N+ patients detected in EUS,shorter survival than N -. (median 27±4.8 vs.113±35.5 months; p<0.01). Similar results for PET-CT (N + 15±2,89 vs. 58±33.8 months; p<0,01). Cox regression analysis both EUS (p=0.03) and PET-CT staging (p=0.013) influences mortality when controlled by age, sex and Charlson status.
Conclusions
EUS restaging after neoadjuvant therapy is more accurate than PET-CT for N staging. Both procedures shown a prognostic influence on survival of those patients, even after controlling this influence by age, sex and Charlson status.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.