Feline Epitheliotropic Intestinal Malignant Lymphoma: 10 Cases (1997–2000)

Abstract

The clinical, histopathologic, and immunohistochemical features of 10 cats with epitheliotropic intestinal malignant lymphoma (EIL) are described. Intestinal biopsy samples were reviewed by 3 pathologists to confirm the diagnosis of EIL. These samples (n = 10) were compared to the intestinal biopsies of normal cats (n = 11), cats with inflammatory bowel disease (IBD; n = 7), and cats with non-EIL (n = 9) for quantification and immunophenotyping of intraepithelial lymphocytes. Immunophenotypic studies were performed with CD3 and CD79a antibody stains to assess for T- and B-cell immunoreactivity, respectively. EIL biopsies had markedly more intraepithelial lymphocytes than normal intestine (NRL) and samples from cats with IBD. However, no marked difference was observed in the number of intraepithelial lymphocytes in cats with non-EIL compared to cats with EIL. Regardless of the histologic diagnosis, the intraepithelial lymphocytes in all cats were small- to intermediate-sized T cells. Clinical findings and imaging studies in the cats identified minimal or nonspecific findings in affected cats. Most cats fit the typical profile of cats with IBD or alimentary malignant lymphoma. Nine of 10 cats with EIL were treated with prednisone with or without additional chemotherapy. Four cats were refractory to chemotherapy and were euthanized within 3.5 months. The remaining 5 cats had long-term survival times of 11 months or greater. The median survival time was 11 months. Additional studies are warranted to better characterize EIL and its relationship to IBD in cats and non-EIL and to identify optimal treatment strategies for this disease.

A Retrospective Study of Feline Gastric Lymphoma in 16 Chemotherapy-Treated Cats

“…Those remission and survival times of cats with gastric lymphoma were comparable to those in previous reports of high-grade feline lymphoma. 16,[19][20][21][22][23][24] Although a chlorambucil and prednisolone protocol is not typically used in the treatment of high-grade lymphoma, the one cat receiving that protocol in this study did so due to owner prefer- This study supports the fact that future studies to investigate the benefit of surgery in treatment of feline gastric lymphoma and the hormonal impact on the risk and response to treatment in feline gastric lymphoma are warranted. Additionally, prospective studies to identify a more favorable chemotherapy protocol, either first-line or rescue, based on remission duration and associated toxicities are very much needed for this disease.…”

“…The median age of cats with gastric lymphoma was 12.8 yr, similar to previous reports of gastrointestinal lymphoma. 2,5,[21][22][23][24] Vomiting was the most common clinical sign reported in this study, in contrast to most reports of feline gastrointestinal lymphoma in which weight loss was more common. 2,19,21,23,24 Lymphoma of the gastrointestinal tract can present as either diffuse infiltration or a discrete mass.…”

“…17 Within gastrointestinal lymphoma, median survival times vary widely from 2 mo to 24 mo and specific location has not been shown to be prognostic. [19][20][21][22][23][24] Across all studies, the most consistent prognostic factor in feline lymphoma is response to treatment. Survival times for cats with various anatomic forms of lymphoma treated with the University of Wisconsin-Madison chemotherapy protocol are 210 days overall, with a median of 654 days for cats achieving a complete response and 122 days for cats with a partial response.…”

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

“…Feline GI small cell T-cell lymphoma is becoming recognized as a distinct form of GI lymphoma in cats, 4,5,9,12,16 and appears similar to IBD on ultrasound and histology. Both IBD and lymphoma are characterized by diffuse or segmental distribution in the small intestine, with ultrasonographic features of bowel wall thickening owing to increase of the muscularis propria and preservation of wall layers without mass formation.…”

Treatment of Feline Gastrointestinal Small-Cell Lymphoma With Chlorambucil and Glucocorticoids

“…4 Carreras et al reported on 10 cases of feline epitheliotropic intestinal lymphoma, all of which were described as consisting of small to intermediate-sized lymphocytes, and all stained positive for presence of the CD3 T-cell marker. 13 …”