B-cell lymphoma

From Felipedia

B-cell lymphoma in a cat. One lymphatic follicle (lower left) is invaded by lymphoid cells, but another (upper right) is not. Giemsa stain. Bar = 250 μm

In this area, large lymphoma cells with vesicular or irregular nuclei are visible, and the cytoplasm is not very abundant in the majority of cells. Hematoxylin and eosin stain. Bar = 10 μm. 2B. This field consists of relatively small cells, and several plasmacytoid cells with eccentrically located nuclei are admixed with them. Hematoxylin and eosin stain. Bar = 10 μm.

B-cell lymphomas (BCLs) in cats are usually distinguished from other forms of feline lymphoma on histological examination^[1].

There are no proven causes of B-cell lymphoma, although Spirochetes have been observed in a feline epitheliotropic T cell gastrointestinal tract lymphoma and a natural killer-like T cell lymphoma. There were Helicobacter spp-like organisms and spirochetes in a cougar affected with gastroduodenal adenocarcinoma and rectal adenoma^[2]. Unlike in human lymphomas associated with Helicobacter pylori or Borrelia burgdorferi, the etiologic significance of spiral-shaped bacteria is not clear in feline lymphoid neoplasms, but records of such bacteria including Flexispira-like organisms in the present study would be helpful in further etiologic studies^[3][4].

Normally affecting intestinal lymphoid cells, BCLs are characterized by a minority of neoplastic B-cells (10%) in a reactive T-cell background. Unlike the human disease, the production of immunoglobulin (Ig) has yet to be ascertained in feline B-cell lymphoma^[5]. In humans, the importance of identifying T-cell-rich BCL is to distinguish it from HD or T-cell lymphoma, which are treated differently and have different prognoses. In one report, reclassification of 5% of LPHD diagnoses to T-cell-rich BCL was made on the basis of absence of characteristic L+H cells and transformed germinal centers. Furthermore, these patients presented with an aggressive and advanced stage of disease, which is very unusual for LPHD. Misdiagnosis of T-cell-rich BCL as HD occurred in 5% and 26% of cases in two studies, respectively. This diagnostic dilemma appears to present confusion in the veterinary literature as well^[6][7].

Treatment for B-cell lymphoma in cats is currently identical to that recommended for T-cell lymphoma.

References

1. ↑ Valli VE, Jacobs RM, Norris A, et al (2000) The histologic classification of 602 cases of feline lymphoproliferative disease using the National Cancer Institute working formulation. J Vet Diagn Invest 12:295–306
2. ↑ Ezura K, Ezura K, Nomura I, Takahashi T, Shibahara T, Kadota K (2004) Natural killer-like T cell lymphoma in a cat. Vet Rec 154:268–270
3. ↑ August, JR (2006) Consultations in feline internal medicine. Vol 5. Elsevier Saunders, Philadelphia. pp:633-641
4. ↑ Ohshima M, Morita T, Sawada M, Shimada A, Kobayashi H, Sawashima K (2004) B-cell immunoblastic lymphoma with multinucleated giant cells in a cat. J Vet Med Sci 66:189–191
5. ↑ Kazuhiko Ezura, Kiyomi Ezura, Izumi Nomura, Yoshiharu Ishikawa, and Koichi Kadota (2007) Immunoblastic lymphoma of germinal center origin in a cat. Can Vet J 48(2):211–213
6. ↑ Yamazaki Y, Aono I, Ohya T, Shibahara T, Kadota K (2002) Gastroduodenal adenocarcinomas and rectal adenoma in a cougar (Felis concolor) infected with Helicobacter-like organisms and spirochetes. J Vet Med Sci 64:149–153
7. ↑ Krecic MR, Black SS (2000) Epitheliotropic T-cell gastrointestinal tract lymphosarcoma with metastases to lung and skeletal muscle in a cat. J Am Vet Med Assoc 216:524–529