Computed Tomography Features of Gastric Cancer Patients With DNA Mismatch Repair Deficiency.

Qian Cao,Yang Lu,Shuai Chen,Nan Xu,Xin-Sheng Zhang,Xiang Li,Sheng-Yuan Lai

doi:10.3389/fonc.2021.619439

Abstract

ObjectiveTo explore the computed tomography (CT) features of gastric cancer (GC) patients with DNA mismatch repair deficiency (dMMR).Materials and MethodsThis study reviewed the clinical and CT features of GC patients with dMMR, confirmed by the postoperative results, between September 2017 and December 2019. The expression pattern of MMR major proteins (MLH1, MSH2, MSH6, and PMS2) in immunohistochemistry was used to confirm the MMR status in GC tissues. The correlation between pre-treatment CT features and MMR status was statistically analyzed.ResultsA total of 28 patients with GC were diagnosed as dMMR in our study, and 49 patients were MMR-proficient (pMMR). The tumor locations were significantly different between the dMMR and pMMR groups (p = 0.006). The CT tumor thickness, CT long and short diameters of the largest lymph node, and the number of lymph nodes on CT of the dMMR group were significantly different from the pMMR group.ConclusionThe dMMR GC exhibited a lower stomach location, smaller tumor thickness and lymph node diameter, and fewer lymph nodes on CT imaging.

Highlights

Gastric cancer (GC) or adenocarcinoma is one of the most common cancers and a common cause of cancer-related deaths worldwide [1, 2]
The tumor locations were significantly different between the dMMR and pMMR groups (p =0.006)
The age, gender, tumor size, histological differentiation degree, and pathological stage showed no statistical differences between the dMMR and pMMR groups (p > 0.05) (Table 1)

Summary

Introduction

Gastric cancer (GC) or adenocarcinoma is one of the most common cancers and a common cause of cancer-related deaths worldwide [1, 2]. GC is an aggressive disease, and many GC patients have locally advanced disease at presentation in China [3]. The Cancer Genome Atlas has identified microsatellite instability (MSI) with or without DNA mismatch repair deficiency (dMMR) as a hallmark of the second molecular subtype of GC. Immunotherapy in solid malignant tumors, including GC, has been rapidly evolving. Immune checkpoint inhibitors, including antiprogrammed death-1 (PD-1) and anti–cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) antibodies, were effective for MSI-high or dMMR solid tumors in many trials [4]. The dMMR status often requires postoperative pathological immunohistochemical results or polymerase chain reaction testing

Methods

Results

Conclusion