Categorized: Gastroenterology
Miraca Life Sciences Highlights at DDW 2011
At DDW this past May, Inform Diagnostics pathologists once again had a significant presence with two abstracts presented as oral platform presentations and six posters. Below are the two platform presentations followed by two selected asbtracts regarding eosinophilic esophagitis. All the abstracts can be viewed in their entirity at miracalifesciences.com.
Drs. Redston and Lash looked at the mismatch repair (MMR) protein status of 900 patients with adenomas containing high grade dysplasia (High Yield of Screening for Lynch Syndrome in Precancerous Colorectal Polyps: A Study of 898 Patients). These patients have never been screened for Lynch Syndrome before, and it was unknown what the yield might be for analyzing these pre-malignant polyps. Twenty-seven of the screened patients (3%) were found to have probable Lynch Syndrome (PLS), a rate very similar to that of screening cancer patients (3.5%). Compared to patients with MMR intact high-grade dysplasia, these patients were more likely to have right-sided lesions. While PLS was significantly more prevalent in patients less than age 50, surprisingly the majority of PLS patients were older than 50 years. Almost half of probable LS patients had no clinical features to suggest LS prior to MMR screening. These results show the value of routine laboratory screening for LS in the community practice setting, even among patients with adenomas with high-grade dysplasia. In addition to appropriate family screening,this novel approach to the detection of LS at the precancerous stage allows for adjustment of surveillance protocols designed to prevent invasive cancer for the index patient.
Inform Diagnostics pathologists Lash and Genta, in collaboration with a team from the division of gastroenterology at the UT Southwestern Medical Center at Dallas used the Inform Diagnostics Database to estimate the size-specific prevalence of high-grade dysplasia (HGD) in more than 125,000 patients with colorectal adenomas. The data showed that the prevalence of HGD in adenomas was proportional to size, and although HGD in adenomas <6mm and 6-9mm was lower than in larger adenomas, the absolute number of small adenoma biopsies with HGD was substantial, accounting for the majority of polyps with HGD. These results provide a robust, nationally representative estimate of the size-specific prevalence of HGD among adenomas, and are likely to be used to inform national policy regarding triage of lesions visualized by computerized tomography colonoscopy (“virtual colonoscopy”).
In Differences in the Prevalence of Eosinophilic Esophagitis Among United States Climate Zones, (Hurrell and Genta) hypothesized that geographic and climatic factors, which are critical determinants of regional flora and environmental antigens, could influence the epidemiology of EoE. By analyzing the geographic distribution of almost 10,000 patients with a diagnosis of EoE made at Inform Diagnostics Life Sciences between 2008 and 2010, the authors unveiled significant regional differences in the epidemiology of EoE: cold climates with abundant snow (for example Alaska, and certain areas of Utah and Idaho) were associated with significantly higher prevalence than warm tropical regions (Florida, Puerto Rico). These findings, now confirmed by more in-depth sub-analyses, support the hypothesis that exposure to environmental antigens may play a significant role in the pathogenesis of EoE.
In Biopsy Practice Patterns and Diagnostic Yield in cases of Suspected Eosinophilic Esophagitis in the United States, (Kapel and Genta) attempted to determine to what extent endoscopists follow the 2007 American Gastroenterological Association Institute guidelines for EoEdiagnostic testing and biopsy procurement guidelines, which suggest that multiple biopsy specimens should be obtained from different esophageal locations along the length of the esophagus. In an analysis of more than 21,000 patients in whom EoE was clinically suspected, the authors discovered that the consensus guidelines with regard to biopsy technique were followed in only 37% of patients with suspected EoE. The authors also found that a histopathologic diagnosis of EoE was made in 9% of the patients who had a single esophageal site biopsy, but increased to 17% for two sites, 33% for three sites, and to 47% for four sites. They concluded that these data provide further strong support for the need to follow the multiple-site biopsy guidelines recommended by the AGA.