Ultrasonographic Evaluation of the Muscularis Propria in Cats with Diffuse Small Intestinal Lymphoma or Inflammatory Bowel Disease

Abstract

Background: An ultrasonographic pattern of thickened muscularis propria in the small intestine and lymphadenopathy have been associated with gastrointestinal lymphoma and inflammatory bowel disease (IBD) in cats.Objectives: To investigate the association of these imaging biomarkers with IBD and lymphoma in cats. Animals: One hundred and forty-two cats with a histologic diagnosis of normal small intestine (SI) (n 5 56), lymphoma (n 5 62), or IBD (n 5 24).Methods: Retrospective case review. Pathology records from 1998-2006 were searched for cats with a diagnosis of normal, IBD, or lymphoma, an ultrasonographic examination o28 days before surgery, and without ultrasonographic evidence of a mass. Multinomial regression analysis was used to determine the association of imaging biomarkers with disease status.Results: Cats with thickening of the muscularis propria detected by ultrasonographic examination were more likely to have lymphoma compared with normal SI cats (odds ratio [OR] 5 4.0, 95% confidence interval [95% CI] 1.2-13.1, P 5 .021) and those with IBD (OR 5 18.8, 95% CI 2.2-162.7, P 5 .008). Histologic samples of cats with muscularis propria thickening were more likely to have disease infiltrates in both the mucosal and submucosal layers (OR 5 8.1, 95% CI 1.7-38.4, P 5 .008) than cats with normal SI. Cats with ultrasonographic evidence of lymphadenopathy were more likely to have a diagnosis of lymphoma (OR 5 44.9, 95% CI 5.1-393.0, P 5 .001) or IBD (OR 5 10.8, 95% CI 1.1-106.3, P 5 .041) than normal SI. Fifty-six of 62 cats had confirmed or presumptive diagnosis of diffuse T-cell lymphoma.Conclusions and Clinical Relevance: Older cats with muscularis layer thickening are more likely to have T-cell lymphoma than IBD. The ultrasonographic pattern is associated with histologic infiltrates in the mucosal and submucosal layers of small intestine. Lymphadenopathy is associated with lymphoma or IBD.

Ultrasonographic thickening of the muscularis propria in feline small intestinal small cell T-cell lymphoma and inflammatory bowel disease

“…The other layers of the intestinal wall did not differ significantly between the affected and healthy cats. These results are in accordance with a previous study in cats with diffuse small cell T-cell GI lymphoma, 7 where the main change noted on ultrasonographic examination was muscularis propria thickening. There was a relationship between the age of the cat and the width of the submucosa and muscularis layer in the ileum, and of the full intestinal thickness in the jejunal segments.…”

“…No cats in the IBD group had disease deeper than the mucosal layer. A relationship between the thickness of the muscularis layer and the extent of the neoplastic lymphocytic infiltration has been described previously, 7 with the muscularis thickening giving increased odds of transmural disease to the depth of the submucosa. This is supported by the current results in which the majority of bowel segments had transmural disease histologically.…”

Clinical characteristics and outcome in dogs with small cell T‐cell intestinal lymphoma

“…The reported ultrasonographic features of small cell intestinal lymphoma in cats include diffuse intestinal wall thickening (most specifically, a thickened muscularis propria) with or without preservation of wall layering and mesenteric lymph node enlargement(17,31). In the current study, these were also common findings in dogs.…”

Linfoma linfocítico difuso en el íleon de un felino: informe clínico-patológico

“…Recientes estudios, mediante la ultrasonografía, han podido determinar la afectación de la capa muscular del intestino y el compromiso de los linfonódulos (9). También con esta ayuda diagnóstica se podrían hacer aspirados con aguja fina para confirmar el resultado histopatológico (7,10) Otra herramienta es la endoscopia, la cual serviría para visualizar el compromiso del tubo digestivo y la obtención de muestras para el análisis histopatológico (1,11), aunque no hay una apariencia endoscópica patognomónica de la neoplasia intes-Linfoma linfocítico difuso en el íleon de un felino: informe clínico-patológico tinal; por eso siempre tienen que tomarse biopsias, para diferenciar de qué tipo de neoplasia se trata o si es una lesión inflamatoria (11). Dentro de las desventajas que puede presentar la utilización de la endoscopia, está la de no poder recuperar especímenes ideales que permitan un buen estudio histopatológico (1); adicional a esto, se puede correr el riesgo de perforaciones intestinales con las consiguientes peritonitis (12).…”