Canine T-cell lymphomas: a morphological, immunological, and clinical study of 46 new cases.
The aim of this study is to report 46 new cases of canine T-cell lymphomas among a series of 140 lymphomas studied by immunophenotyping (incidence 32.8%). According to the updated Kiel classification adapted to the canine species, 13 were classified as low-grade and 33 as high-grade lymphomas. Among the low-grade lymphomas, five were small clear-cell lymphomas, three were pleomorphic small-cell lymphomas, and five mycosis fungoides. Among the high-grade cases, there were 11 pleomorphic mixed-, small-, and large-cell lymphomas, 6 pleomorphic large-cell lymphomas, 11 lymphoblastic lymphomas, and 5 unclassifiable high-grade plasmacytoid lymphomas. The cytohistologic features were highly suggestive of a T-cell phenotype on the basis of cell morphology (irregular nuclei and clear cytoplasms) (30/46 cases), a T-cell zone pattern, and the presence of hyperplastic postcapillary venules (22/46 cases). All 46 cases were CD3+ CD79a-, and among 34 cases investigated for CD4 and CD8 expression, 13 were CD4+CD8-, 13 were CD8+CD4-, and 8 were CD4CD8 double positive or double negative. The pleomorphic mixed lymphomas were mainly CD4+CD8- (6/7) and the lymphoblastic lymphomas were double positive or double negative (6/8). The main clinical, hematologic, and biochemical features were generalized (28/46) or regional lymphadenopathy (16/46), hepatosplenomegaly (15/46), extranodal involvement (11/46), mediastinal mass (9/46), and leukemia (8/46), which were mainly present in cases of lymphoblastic lymphomas and hypercalcemia (16/46).
Fournel-Fleury
C
C
Laboratoire d'Hématologie-Cytologie-Immunopathologie, Ecole Nationale Vétérinaire de Lyon, France. c.fournel@vet-lyon.fr
Ponce
F
F
Felman
P
P
Blavier
A
A
Bonnefont
C
C
Chabanne
L
L
Marchal
T
T
Cadore
J L
JL
Goy-Thollot
I
I
Ledieu
D
D
Ghernati
I
I
Magnol
J P
JP
D000818:Animals; D001706:Biopsy / Q000379:methods / Q000662:veterinary; D001707:Biopsy, Needle / Q000379:methods / Q000662:veterinary; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000453:epidemiology / Q000276:immunology / Q000473:pathology*; D004285:Dogs; D005602:France / Q000453:epidemiology; D016130:Immunophenotyping; D015994:Incidence; D016399:Lymphoma, T-Cell / Q000453:epidemiology / Q000276:immunology / Q000473:pathology / Q000662:veterinary*