Endoscopic Screening and Surveillance for Gastric Cancer

Lynch syndrome (LS) predisposes affected individuals to a high lifetime risk of malignancies, including colorectal, endometrial, gastric, and duodenal cancers. The role of upper GI (UGI) cancer screening in LS has been uncertain, but recent studies have evaluated its utility.

Databases were queried through December 2021 to identify studies that examined upper endoscopy screening in LS using EGD. Mantel-Haenszel pooled odds ratios and 95% confidence intervals (CIs) for outcomes were constructed using a random-effects model to identify pooled odds of endoscopic findings in persons with LS. Event rates for detection of gastric and duodenal cancers, high-risk lesions, and clinically actionable findings were calculated. Statistical heterogeneity was assessed using the I² statistic.

Nine studies were identified with 2356 LS patients undergoing approximately 7838 EGDs. In total, 47 LS-associated UGI cancers (18 gastric and 29 duodenal cancers), 237 high-risk lesions, and 335 clinically actionable findings were identified. The pooled event rate for detection of any UGI cancer, high-risk lesions, and clinically actionable findings during screening were .9% (95% CI, .3-2.1; I² = 89%), 4.2% (95% CI, 1.6-10.9; I² = 98%), and 6.2% (95% CI, 2.2-16.5; I² = 99%), respectively. There was no difference between LS-associated gene and gastric or duodenal cancer detection.

In LS, there is evidence that endoscopic screening detects UGI cancers, precancerous lesions, and other clinically actionable findings that favor its use as a part of cancer risk management in LS.

Gastric cancer is one of the common malignant tumors in the world, which originates from the gene mutation of human cells. In this work, an atomic force microscope was used to quantitatively detect the changes of multiple physical parameters such as the cell morphology, surface roughness, elasticity modulus and adhesion force before and after Phellinus linteus stimulation. The experimental results show that Phellinus linteus can change the shape of gastric cancer cells (SGC-7901) from flat to spherical, and increase their height and surface roughness values.

The adhesion force of cells is reduced and the elasticity modulus is increased. But there are no significant differences in the morphology and mechanical properties of gastric epithelial cells (GES-1). The results indicate that Phellinus linteus has a high anticancer effect on the gastric cancer cells, but has less toxic side effects on the gastric epithelial cells. This work proves that Phellinus linteus can be used as a preferred anticancer drug for the treatment of gastric cancer cells.

In the present study, real-time quaking-induced conversion (RT-QuIC) assay was used to evaluate pathologic alpha-synuclein (AS) seeding activity in formalin-fixed paraffin-embedded (FFPE) tissue from the gastrointestinal (GI) tract of Parkinson's disease (PD) patients.

This study was conducted in two parts: Part I. a preliminary autopsy study that included four autopsy-confirmed patients with synucleinopathy (2 PD, 1 dementia with Lewy bodies [DLB], and 1 multiple system atrophy [MSA]) and two normal autopsy controls. Frozen and FFPE tissues of the brain were obtained. Part II. a clinical case-control study that included 20 clinically diagnosed PD patients and matched controls. Surgically resected FFPE tissues from the upper and lower GI tracts were used. The RT-QuIC assay was performed to evaluate pathologic seed amplification using frozen or FFPE tissues. The presence or absence of AS aggregation was confirmed by conventional phosphorylated AS (pAS) immunohistochemistry (IHC).

In Part I, RT-QuIC assay showed pathologic AS amplification in frozen and FFPE brain tissues of PD and DLB patients, and FFPE stomach tissue of PD patients but not in the MSA patient and controls. In Part II, pathologic seeding activity was found in 10% (2/20) of the stomach tissues of clinical PD patients but in none of the matched controls. IHC showed pAS-positive staining in 55% of patients (11/20) and 15% of controls (3/20).

The present study results showed that the RT-QuIC assay using FFPE tissue of the GI tract was inadequate as a biomarker in PD.