Tumor regression grade (TRG) for gastric cancer and radiological methods on predicting response to perioperative chemotherapy: a narrative review

Background and Objective: Perioperative chemotherapy has been increasingly practiced on gastric cancer (GC) in Western Countries where two third of the patients have locally advanced disease at diagnosis. The histological radiological evaluation tumor response to are both cornerstones this multimodal therapy predict oncological outcomes. This article aims review current regression grade (TRG) classification systems available give an overview regarding methods predicting therapy.