Histopathologic classification of 171 cases of canine and feline non-Hodgkin lymphoma according to the WHO

Abstract

A retrospective collection of 171 lymphoid neoplasms (123 dogs and 48 cats) was classified according to the Revised European-American Lymphoma (REAL) classification, adopted in 2002 by the World Health Organization (WHO), to evaluate the WHO system for categorization of canine and feline neoplasms. Microscopic examination was performed after standard hematoxylin-eosin staining and immunohistochemical labelling for B (CD79a) or T (CD3) cell phenotypes. B-cell lymphomas were prevalent in dogs and T-cell lymphomas in cats. B-Large cell lymphoma (B-LCL) frequently showed plasmacytoid differentiation; notably, two canine plasma cell tumours (PCT) expressed both CD79 and CD3. There were difficulties in differentiating B-lymphoblastic lymphoma (B-LBL) from Burkitt-type lymphoma. Furthermore, intestinal T-cell lymphoma (ITCL) exhibited a huge morphologic variability. Finally, multicentric mature small and thymic T-cell lymphomas were diagnosed, although these categories are not codified by the WHO classification.

B‐cell lymphoblastic lymphoma of the nictitating membrane as the first presenting sign in a 2‐year‐old Springer Spaniel

“…Canine B‐LBL is less common than the T‐cell counterpart T‐LBL3; however, it seems that LBL is more frequent in younger individuals, as in the present case 20…”

“…B‐cell lymphoblastic lymphoma (B‐LBL) is a precursor subtype of lymphoma that accounts for 1.8%‐2.4%3, 4 of all canine lymphomas.…”

“…These had densely stained cells in hematoxylin‐eosin staining of moderate size with intermediate‐sized nuclei and finely distributed chromatin, indistinct nucleoli, and scant cytoplasm 3. The architecture of the cells was diffuse, and there was a high mitotic rate 3…”

Comparative oncology: what dogs and other species can teach us about humans with cancer

“…The high degree of similarity between human and canine lymphoma has been extremely helpful in understanding this disease in both species [97 -99]. The high similarity in pathologic presentation of canine and human lymphoma allows for use of World Health Organization (WHO) criteria for accurate and reproducible classification of the canine tumours [100,101]. In human NHL, the vast majority (approx.…”

Epidemiological, clinical and immunohistochemical aspects of canine lymphoma in the region of Porto Alegre, Brazil

“…Recognition that lymphoma cells derive from T or B cells is very important because the immunophenotype is also related to prognosis. Most canine lymphomas are type B (Fournel-Fleury et al 1997, Vezzali et al 2009, Ponce et al 2010, and dogs with T-cell lymphomas exhibited a low complete response rate to chemotherapy as well as shortened remission and survival times (Greenlee et al 1990). The clinical features of human lymphoma vary among different countries and regions; in the western world the majority of lymphomas are of B-cell origin and some 10-20% are T-cell lymphomas, while in Asia T-cell lymphoma are more common (Fisher & Fisher 2004).…”