| dc.description.abstract | Cutaneous lymphomas are uncommon tumors in dogs that can occur as epitheliotropic and
non-epitheliotropic types. The epitheliotropic type comprises three distinct clinicopathological
presentations already well established. However, the non-epitheliotropic lymphoma, despite
has been recognized is poorly characterized, representing a heterogeneous group of
presentations not yet correlated and that apparently can mimic different skin tumors,
configuring a diagnostic challenge. Therefore, this study aimed mainly establish whether there
is a correlation between the macroscopic presentation and the histological subtypes of
cutaneous non-epitheliotropic lymphoma in the population of dogs under study. Additionally,
aimed to determine the prevalence of each type and histological subtype of canine cutaneous
lymphoma, and describe the epidemiological and anatomopathological characteristics of the
cases. From a total of 38 cases of cutaneous lymphoma diagnosed in dogs, 17 (44,7%) cases
were considered as epitheliotropic and 21 (55,3%) cases as non-epitheliotropic. From 17 cases
of cutaneous epitheliotropic lymphoma, 13 (34,2%) were subclassified as mycosis fungoides,
and four (10,5%) as pagetoid reticulosis. The cases of cutaneous non-epitheliotropic
lymphoma included: anaplastic large T-cell lymphoma (ALTCL [9/21 {23,9%}]), peripheral
T-cell lymphoma, unspecified (PTCL-NOS [4/21 {10,5%}]), subcutaneous panniculitis-like
T-cell lymphoma (SPTCL [4/21 {10,5%}]), diffuse large B-cell lymphoma – immunoblastic
type (DLBCL [2/21 {5,2%}]), lymphomatoid granulomatosis (LYG [1/21 {2,6%}]), and
marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) –
lymphoplasmacytic variant (1/21 [2,6%]). Based on the anatomopathological findings, it was
possible to infer that when faced with multiple, nodular or placoid skin lesions, predominantly
on the trunk and limbs, the diagnosis is more likely to be consistent with ALTCL. Whereas,
with solitary skin nodules or plaques, PTCL-NOS will be the most frequently seen
histological type. When these lesions are exclusively located in the subcutaneous tissue, one
should first think about SPTCL and, more rarely, DLBCL. Regarding to epitheliotropic
cutaneous lymphomas, the cutaneous form of mycosis fungoides is the most commonly
observed in dogs, especially in the pre-mycotic and mycotic phases. We hope that this
information can assist veterinary clinicians and pathologists in their diagnostic routines, and
contribute to the characterization of non-epitheliotropic cutaneous lymphomas in the canine
species. | |
