Effect of Sample Quality on the Sensitivity of Endoscopic Biopsy for Detecting Gastric and Duodenal Lesions in Dogs and Cats

Abstract

Background: The quality of histopathology slides of endoscopic biopsies from different laboratories varies, but the effect of biopsy quality on outcome is unknown.Hypothesis: The ability to demonstrate a histologic lesion in the stomach or duodenum of a dog or cat is affected by the quality of endoscopic biopsy samples submitted. More endoscopic samples are needed to find a lesion in poor-quality tissue specimens.Animals: Tissues from 99 dogs and 51 cats were examined as clinical cases at 8 veterinary institutions or practices in 5 countries.Methods: Histopathology slides from sequential cases that underwent endoscopic biopsy were submitted by participating institutions. Quality of the histologic section of tissue (inadequate, marginal, adequate), type of lesion (lymphangiectasia, crypt lesion, villus blunting, cellular infiltrate), and severity of lesion (normal, mild, moderate, severe) were determined. Sensitivity of different quality tissue samples for finding different lesions was determined.Results: Fewer samples were required from dogs for diagnosis as the quality of the sample improved from inadequate to marginal to adequate. Duodenal lesions in cats displayed the same trend except for moderate duodenal infiltrates for which quality of tissue sample made no difference. Gastric lesions in dogs and mild gastric lesions in cats had the same trend, whereas the number of tissue samples needed to diagnose moderately severe gastric lesions in cats was not affected by the quality of tissue sample.Conclusions and Clinical Importance: The quality of endoscopically obtained tissue samples has a profound effect on their sensitivity for identifying certain lesions, and there are differences between biopsies of canine and feline tissues.

Sensitivity for the Detection of a Clonally Rearranged Antigen Receptor Gene in Endoscopically Obtained Biopsy Specimens from Canine Alimentary Lymphoma

“…Therefore, there is a possibility that the samples for histopathological examination had rich tumor cells, while those for PCR examination had fewer or no tumor cells in the specimen. Furthermore, the quality of the sample is known to affect the result of histopathological diagnostic sensitivity [12], which may lead to a discrepancy between the findings of histopathology and PCR analysis. Five FFPE samples were included in this study; these samples had a potential risk of DNA fragmentation during the process of formalin fixation [1].…”

Application of Polymerase Chain Reaction to Analysis of Antigen Receptor Rearrangements to Support Endoscopic Diagnosis of Canine Alimentary Lymphoma

“…This may have resulted from subtle differences between the biopsy specimens because they were taken from close, but not identical lesions. Moreover, it has been reported that interobserver variation and the quality of endoscopic biopsy specimens influences histopathological outcome [19,20]. Since the endoscopic biopsy specimens were taken by several operators and evaluated by several pathologists, this may have influenced the histopathological diagnoses obtained in the present study.…”

Gastrointestinal B-lymphoblastic lymphoma in a dog: a case report

“…Endoscopy, which was chosen in the reported dog, is the least invasive technique; it allows inspection of gastric and intestinal mucosa and the collection of multiple samples from different sites (Washabau et al 2010). According to Willard et al (2008), endoscopy can be an effective tool for diagnosing GI mucosal lymphoma in dogs. The samples should be obtained from all endoscopically accessible segments of the GI tract.…”