Clinicopathological Characteristics and Prognostic Value of Epstein-Barr Virus-associated Gastric Cancer, Microsatellite Instability and PD-L1 Immunoexpression

Abstract Objectives Gastric cancer (GC) is the 4th most common type of cancer worldwide. Different GC subtypes have unique molecular features that may have different therapeutic methods. The aim of the present study was to investigate Epstein-Barr virus (EBV) infection, microsatellite instability (MSI) status, the expression of programmed death-ligand 1 (PD-L1) and gene mutations in GC patients. Methods The data of 2504 GC patients, who underwent curative gastrectomy with lymphadenectomy at Peking University Cancer Hospital between 2013 and 2018, were reviewed. We analyzed the clinicopathological factors associated with the immunohistochemistry (IHC) profiles of these patients, and genetic alterations were analyzed using next generation sequencing (NGS). Results Mismatch repair-deficient (d-MMR) GC patients were found to have a higher probability of expressing PD-L1 (p = 0.000, PD-L1 cutoff value = 1%). In addition, 4 and 6.9% of the 2504 gastric cancer patients were EBV-positive and d-MMR, respectively. The number of MLH1/PMS2-negative cases was 126 (6%), and the number of MSH2/MSH6-negative cases was 14 (0.9%). d-MMR status was associated with a intestinal group (p = 0.012), but not with tumor differentiation. Furthermore, MSI and d-MMR GC status (detected by NGS and IHC, respectively) were consistently high, and the rate of MSI was higher in patients with d-MMR GC. A number of genes associated with DNA damage repair were detected in GC patients with MSI, including POLE, ETV6, BRCA and RNF43. In patients with a high tumor mutation burden, the most significantly mutated genes were LRP1B (79.07%), ARID1A (74.42%), RNF43 (69.77%), ZFHX3 (65.12%), TP53 (58.14%), GANS (51.16%), BRCA2 (51.16%), PIK3CA (51.16%), NOTCH1 (51.16%), SMARCA4 (48.84%), ATR (46.51%), POLE (41.86%) and ATM (39.53%). Conclusions Using IHC and NGS, MSI status, protein expression, tumor mutation burden (TMB) and genetic alterations were identified in patients with GC, which provides a theoretical basis for the future clinical treatment of GC.

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Clinicopathological features of Epstein-Barr virus infection, microsatellite instability, tumor mutation burden and PD-L1 status in Chinese patients with gastric cancer

10.21203/rs.3.rs-48875/v3 ◽

2020 ◽

Author(s):

Li Zhang ◽

Aiwen Wu ◽

Zhongwu Li

Keyword(s):

Gastric Cancer ◽

Microsatellite Instability ◽

Epstein Barr Virus ◽

Genetic Alterations ◽

Epstein Barr Virus Infection ◽

Tumor Mutation Burden ◽

Barr Virus ◽

Mutation Burden ◽

Therapeutic Decisions ◽

Epstein Barr

Abstract Objectives: Gastric cancer (GC) is the 4th most common type of cancer worldwide. Different GC subtypes exhibit unique molecular features that may potentially guide therapeutic decisions. The aim of the present study was to investigate Epstein-Barr virus (EBV) infection, microsatellite instability (MSI) status, the expression of programmed death-ligand 1 (PD-L1) and gene mutations in patients with surgically-treated GC. Methods: The data of 2,504 GC patients, who underwent potentially curative gastrectomy with lymphadenectomy at Peking University Cancer Hospital between 2013 and 2018, were reviewed from a prospectively collected medical database. We also analyzed the clinicopathological factors associated with the immunohistochemistry (IHC) profiles of these patients, and genetic alterations were analyzed using next generation sequencing (NGS). Results: Mismatch repair-deficient (d-MMR) GC patients were found to have a higher probability of expressing PD-L1 (p<0.001, PD-L1 cutoff value = 1%). In addition, 4 and 6.9% of the 2,504 gastric cancer patients were EBV-positive and d-MMR, respectively. The number of MLH1/PMS2-negative cases was 126 (6%), and the number of MSH2/MSH6-negative cases was 14 (0.9%). d-MMR status was associated with a diffuse/mixed group (p<0.05), but not with tumor differentiation. Furthermore, MSI and d-MMR GC status (detected by NGS and IHC, respectively) were consistently high, and the rate of MSI was higher in patients with d-MMR GC. A number of genes associated with DNA damage repair were detected in GC patients with MSI, including POLE, ETV6, BRCA and RNF43. In patients with a high tumor mutation burden, the most significantly mutated genes were LRP1B (79.07%), ARID1A (74.42%), RNF43 (69.77%), ZFHX3 (65.12%), TP53 (58.14%), GANS (51.16%), BRCA2 (51.16%), PIK3CA (51.16%), NOTCH1 (51.16%), SMARCA4 (48.84%), ATR (46.51%), POLE (41.86%) and ATM (39.53%). Conclusions: Using IHC and NGS, MSI status, protein expression, TMB and genetic alterations were identified in patients with GC, which provides a theoretical basis for the future clinical treatment of GC.

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Clinicopathological features of Epstein-Barr virus infection, microsatellite instability, tumor mutation burden and PD-L1 status in Chinese patients with gastric cancer

10.21203/rs.3.rs-48875/v2 ◽

2020 ◽

Author(s):

Li Zhang ◽

Aiwen Wu ◽

Zhongwu Li

Keyword(s):

Gastric Cancer ◽

Microsatellite Instability ◽

Epstein Barr Virus ◽

Genetic Alterations ◽

Epstein Barr Virus Infection ◽

Tumor Mutation Burden ◽

Barr Virus ◽

Mutation Burden ◽

Therapeutic Decisions ◽

Epstein Barr

Abstract Objectives: Gastric cancer (GC) is the 4th most common type of cancer worldwide. Different GC subtypes exhibit unique molecular features that may potentially guide therapeutic decisions. The aim of the present study was to investigate Epstein-Barr virus (EBV) infection, microsatellite instability (MSI) status, the expression of programmed death-ligand 1 (PD-L1) and gene mutations in patients with surgically-treated GC. Methods: The data of 2,504 GC patients, who underwent potentially curative gastrectomy with lymphadenectomy at Peking University Cancer Hospital between 2013 and 2018, were reviewed from a prospectively collected medical database. We also analyzed the clinicopathological factors associated with the immunohistochemistry (IHC) profiles of these patients, and genetic alterations were analyzed using next generation sequencing (NGS). Results: Mismatch repair-deficient (d-MMR) GC patients were found to have a higher probability of expressing PD-L1 (p<0.001, PD-L1 cutoff value = 1%). In addition, 4 and 6.9% of the 2,504 gastric cancer patients were EBV-positive and d-MMR, respectively. The number of MLH1/PMS2-negative cases was 126 (6%), and the number of MSH2/MSH6-negative cases was 14 (0.9%). d-MMR status was associated with a diffuse/mixed group (p<0.05), but not with tumor differentiation. Furthermore, MSI and d-MMR GC status (detected by NGS and IHC, respectively) were consistently high, and the rate of MSI was higher in patients with d-MMR GC. A number of genes associated with DNA damage repair were detected in GC patients with MSI, including POLE, ETV6, BRCA and RNF43. In patients with a high tumor mutation burden, the most significantly mutated genes were LRP1B (79.07%), ARID1A (74.42%), RNF43 (69.77%), ZFHX3 (65.12%), TP53 (58.14%), GANS (51.16%), BRCA2 (51.16%), PIK3CA (51.16%), NOTCH1 (51.16%), SMARCA4 (48.84%), ATR (46.51%), POLE (41.86%) and ATM (39.53%). Conclusions: Using IHC and NGS, MSI status, protein expression, TMB and genetic alterations were identified in patients with GC, which provides a theoretical basis for the future clinical treatment of GC.

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Clinicopathological Characteristics and Response to Chemotherapy in Treatment-Naive Epstein–Barr Virus Associated Gastric Cancer: A Retrospective Study

Frontiers in Oncology ◽

10.3389/fonc.2021.611676 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tong Xie ◽

Zhi Peng ◽

Yiqiang Liu ◽

Zhening Zhang ◽

Xiaotian Zhang ◽

...

Keyword(s):

Gastric Cancer ◽

Neoadjuvant Chemotherapy ◽

Vascular Invasion ◽

Epstein Barr Virus ◽

Tumor Stage ◽

Clinicopathological Characteristics ◽

Advanced Tumor Stage ◽

Barr Virus ◽

Response To Chemotherapy ◽

Epstein Barr

BackgroundEpstein–Barr virus associated gastric cancer (EBVaGC) is a special subtype of gastric cancer. However, the perioperative treatment plan and the response to chemotherapy are still uncertain.MethodsWe retrospectively enrolled patients diagnosed with EBVaGC from March 2013 to July 2020 in Beijing Cancer Hospital. Clinicopathological characteristics were recorded. Disease-free survival (DFS) were then calculated, and variants affecting DFS were tested in a Cox proportional regression model.ResultsOne hundred sixty consecutive patients were finally included in our study. Of the patients, 96.9% had adenocarcinoma, while five had squamous cell carcinoma component. Most (70.9%) of them were poorly differentiated. Prevalent programmed death-ligand 1 (PD-L1) (69%) and minor HER-2 (3.8%) expression were noticed; all of the patients were MMR proficient (pMMR) or microsatellite stable (MSS). Among 33 patients who experienced neoadjuvant therapy, the number of tumor regression grade (TRG) 1, TRG 2, and TRG 3 was 5, 16, and 12, respectively. Patients with advanced tumor stage and T stage showed poorer response. Thirty-one patients experienced first-line chemotherapy; ORR was 33.3%, and DCR was 61.9%. One hundred forty-seven patients underwent surgery, and 27 of them showed disease recurrence; the 3-year DFS rate was 71.0%. Tumor stage, neoadjuvant chemotherapy, vascular invasion, and negative PD-L1 expression were associated with poorer DFS. Vascular invasion was the independent risk factor of DFS. Only seven patients reached OS with median follow-up time of 14 months.ConclusionEBVaGC exhibits unique clinicopathological characteristics. Neoadjuvant chemotherapy may not be suitable for EBVaGC, and EBVaGC exhibited relatively poor response to chemotherapy.

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