Gastric carcinoma (GC) disproportionately affects Asian Americans. We examined whether history of upper gastrointestinal (GI) endoscopy was associated with lower stage at GC diagnosis among Asian Americans and whether origin of providers influenced referral for endoscopy. We employed Surveillance Epidemiology and End Results-Medicare data on Asian Americans diagnosed with GC in 2004-2013 (n = 1,554). Stage distribution, GI conditions at diagnosis, and history of endoscopy were compared between Asian ethnic groups. Multivariate logistic regression adjusting for age, sex, poverty level, tumor location, and histology was used to examine the association of ethnicity and endoscopic history with stage I disease at diagnosis of GC. Koreans were more likely to be diagnosed with stage I, T1a GC and have prior history of endoscopy, compared with other Asian ethnicities (24% vs. 8% for stage I, T1a; 40% vs. 15% for endoscopy). Patients with primary care providers of concordant ethnic origin were more likely to have history of endoscopy. Asian American patients with GC with history of endoscopy were more likely to be diagnosed with GC at stage I disease (adjusted OR, 3.07; 95% confidence interval, 2.34-4.02). Compared with other Asian Americans, Koreans were diagnosed with GC at earlier stages owing to common history of endoscopy, which was more often undergone by patients with primary care providers of concordant ethnic origin. Overall, upper GI endoscopy was associated with early detection of GC in Asian Americans. Novelty and Impact. It is well-established that Asian Americans in the United States are disproportionately affected by gastric cancer. In our study we found that Asian American patients treated by physicians of similar ethnic background are more likely to undergo upper GI endoscopy in the United States, leading to early detection of gastric cancer and longer survival. Given this, targeted endoscopic screening in Asian Americans should be considered for early detection of GC.

Immunotherapy has been established as a standard in select molecular subgroups of treatment-refractory advanced gastric cancer. However, its role in resectable gastric cancer where perioperative systemic therapy is the standard remains unclear. We present a case of a man who was diagnosed with resectable gastric cancer that was microsatellite stable but programmed death-ligand 1 (PD-L1) and Epstein-Barr Virus (EBV)-positive. Given extenuating circumstances of the SARS-CoV-2 pandemic, preferences to limit exposure to the healthcare setting, and the unique tumor molecular features, neoadjuvant pembrolizumab and capecitabine was pursued after multidisciplinary discussion. He was able to achieve a complete response to this neoadjuvant regimen with no further signs of radiographic or pathologic disease on follow-up. We highlight a dramatic response to this novel approach that represents among the first cases to support a potentially viable neoadjuvant chemoimmunotherapy strategy to resectable gastric cancer. In select patients, perioperative immunotherapy-based therapy may constitute a promising strategy in resectable gastric cancer and warrants further investigation.

Objective

While oesophageal squamous cell carcinoma remains infrequent in Western populations, the incidence of oesophageal adenocarcinoma (EAC) has increased sixfold to eightfold over the past four decades. We aimed to characterise oesophageal cancer-specific and subtypes-specific gene regulation patterns and their upstream transcription factors (TFs).  DESIGN: To identify regulatory elements, we profiled fresh-frozen oesophageal normal samples, tumours and cell lines with chromatin immunoprecipitation sequencing (ChIP-Seq). Mathematical modelling was performed to establish (super)-enhancers landscapes and interconnected transcriptional circuitry formed by master TFs. Coregulation and cooperation between master TFs were investigated by ChIP-Seq, circularised chromosome conformation capture sequencing and luciferase assay. Biological functions of candidate factors were evaluated both in vitro and in vivo.

Results

We found widespread and pervasive alterations of the (super)-enhancer reservoir in both subtypes of oesophageal cancer, leading to transcriptional activation of a myriad of novel oncogenes and signalling pathways, some of which may be exploited pharmacologically (eg, leukemia inhibitory factor (LIF) pathway). Focusing on EAC, we bioinformatically reconstructed and functionally validated an interconnected circuitry formed by four master TFs-ELF3, KLF5, GATA6 and EHF-which promoted each other's expression by interacting with each super-enhancer. Downstream, these master TFs occupied almost all EAC super-enhancers and cooperatively orchestrated EAC transcriptome. Each TF within the transcriptional circuitry was highly and specifically expressed in EAC and functionally promoted EAC cell proliferation and survival.

Conclusions

By establishing cancer-specific and subtype-specific features of the EAC epigenome, our findings promise to transform understanding of the transcriptional dysregulation and addiction of EAC, while providing molecular clues to develop novel therapeutic modalities against this malignancy.