Paper:

RESUMEN CORTO - SHORT SUMMARY

Lymphoma is the most common neoplasia in dogs, and the gastrointestinal tract is the second anatomical site most frequently affected, although peritoneal seeding is rare and has only been described in human medicine and cats.

The clinical case of an 11-year-old French bulldog with a chronic gastrointestinal condition is described. The abdominal ultrasound revealed a segment of mid jejunum with loss of wall layering that consisted of a single hypoechoic layer, and was thickened (8 mm); the adjacent peritoneum was thickened, hyperechogenic, irregular and heterogeneous. The diagnosis of intestinal T-cell lymphoma with peritoneal lymphomatosis was confirmed from the postmortem histopathological study and immunohistochemical staining.

Peritoneal lymphomatosis, to the authors knowledge, has not been described in canine patients. Some cases have been described in cats, although diffuse infiltration of the peritoneum secondary to lymphoma is considered rare, since it is a tissue that does not contain lymphoid elements and the mechanism of invasion is unknown. Ultrasonographic changes reported in cats with peritoneal lymphomatosis include thickened and markedly hyperechoic peritoneum, peritoneal effusion, and nodular hypoechoic lesions, but these are non-specific and may also be seen with other types of neoplasia, or with inflammatory diseases, being cytology or histopathology required for confirmation.

Peritoneal lymphomatosis should be considered as a differential in dogs with ultrasonographically abnormal peritoneum that have a diagnosis of intestinal lymphoma. To the authors knowledge, this clinical case represents the only description of peritoneal involvement secondary to intestinal lymphoma in a dog.

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PERITONEAL LYMPHOMATOSIS IN A DOG: A CASE REPORT