Interobserver agreement of a gastric adenocarcinoma tumor regression grading system that incorporates assessment of lymph nodes

Perioperative chemotherapy is increasingly used in combination with surgery for the treatment of patients with locally advanced, resectable gastric cancer. Histologic tumor regression grade (TRG) has emerged as an important prognostic factor; however, a common standard for its evaluation is lacking. Moreover, the clinical significance of regressive changes in metastatic lymph nodes (LNs) remains unclear. We conducted an international study to examine the interobserver agreement of a TRG system that is based on the Becker system for the primary tumors and additionally incorporates regression grading in LNs. Twenty observers at different levels of experience evaluated the TRG in 60 histologic slides (30 primary tumors and 30 LNs) based on the following criteria: for primary tumors, grade 1 represented complete response (no residual tumor), grade 2 represented 50% residual tumor, as described by Becker et al. For LNs, grade "a" represented complete, grade "b" represented partial, and grade "c" represented no regression. The interobserver agreement was estimated using the Kendall's coefficient of concordance (W). Regarding primary tumors, agreement was good irrespective of the level of experience, reaching a W-value of 0.70 overall, 0.71 among subspecialized, and 0.71 among nonsubspecialized observers. Regarding LNs, interobserver agreement was moderate to good, with W-values of 0.52 overall, 0.64 among subspecialized, and 0.45 among nonsubspecialized observers. These findings indicate that the combination of the Becker TRG system with a three-tiered grading of regression in LNs generates a system that is reproducible. Future studies should investigate whether the additional information of TRG in LNs adds to the prognostic value of histologic regression grading in gastric cancer specimens

sj-pdf-1-ueg-10.1177_2050640620934911 - Supplemental material for European Guideline on IgG4-related digestive disease – UEG and SGF evidence-based recommendations

Supplemental material, sj-pdf-1-ueg-10.1177_2050640620934911 for European Guideline on IgG4-related digestive disease – UEG and SGF evidence-based recommendations by J-Matthias Löhr, Ulrich Beuers, Miroslav Vujasinovic, Domenico Alvaro, Jens Brøndum Frøkjær, Frank Buttgereit, Gabriele Capurso, Emma L Culver, Enrique de-Madaria, Emanuel Della-Torre, Sönke Detlefsen, Enrique Dominguez-Muñoz, Piotr Czubkowski, Nils Ewald, Luca Frulloni, Natalya Gubergrits, Deniz Guney Duman, Thilo Hackert, Julio Iglesias-Garcia, Nikolaos Kartalis, Andrea Laghi, Frank Lammert, Fredrik Lindgren, Alexey Okhlobystin, Grzegorz Oracz, Andrea Parniczky, Raffaella Maria Pozzi Mucelli, Vinciane Rebours, Jonas Rosendahl, Nicolas Schleinitz, Alexander Schneider, Eric FH van Bommel, Caroline Sophie Verbeke, Marie Pierre Vullierme, Heiko Witt and the UEG guideline working group in United European Gastroenterology Journa