RESUMEN
Although hyperthyroidism is the most common endocrine disorder in elderly cats, systematic studies investigating the prevalence of thyroid lesions in feline animals are scarce. Our objective was to evaluate morphological changes in the thyroid glands of 61 cats submitted to necropsy without clinical suspicion of hyperthyroidism. Thirteen (13/61 [21.3%]) cats had thyroid enlargement and 54/61 (88.5%) had some histological thyroid changes. Proliferative lesions were histologically seen in 33/61 (54%) cats while non-proliferative lesions were observed in 48/61 (78.7%) cats. Thyroid hyperplasia (18/33 [54.5%]) and cystic adenoma (6/33 [18.2%]) were the most prevalent proliferative changes and lesions with little or no clinical significance (37/61 [60.6%]), degenerative (31/61 [50.8%]) and inflammatory changes (12/61 [19.7%]) were the most common non-proliferative changes. Among cats with proliferative lesions, 16/33 (48.4%) had a proliferation grade ≥A4, a grade previously associated with clinical hyperthyroidism. Although the cats from this study did not have any clinical diagnosis of thyroid disease, it is possible that one or more had some degree of clinically unnoticed thyroid dysfunction. The high prevalence of follicular lesions in this study highlights the importance of a more careful clinical and pathological investigation regarding thyroid diseases in mature and elderly cats.
RESUMEN
Lymphomas are the tumors most frequently associated with the death or euthanasia of dogs in most parts of the world. In dogs, they almost always occur as disseminated (multicentric lymphoma), gastrointestinal (alimentary lymphoma), or nodal mediastinal (mediastinal lymphoma) diseases. However, other uncommon presentations can occasionally occur. This study aimed to establish the prevalence of these unusual types of lymphoma and demonstrate to veterinary pathologists how they present pathologically. From a total of 100 cases of lymphoma in dogs diagnosed between 1965 and 2017, 16 cases (16/100) were considered by us as non-traditional presentations of the disease: follicular lymphoma, (5/100), peripheral T-cell lymphoma, NOS (2/100), angiocentric lymphoma (2/100), intravascular large T-cell lymphoma (2/100), lymphomatoid granulomatosis (1/100), anaplastic large-cell lymphoma (1/100), hepatosplenic T-cell lymphoma (1/100), and chronic small B-cell lymphocytic lymphoma, intermediate type (1/100). We hope that the results presented here can help veterinary pathologists to recognize such cases of "atypical lymphoma" in their diagnostic routines.(AU)
Linfomas são os tumores mais associados a morte ou eutanásia de cães na maior parte do mundo. Nessa espécie animal ocorrem quase sempre como uma doença disseminada (linfoma multicêntrico), gastrintestinal (linfoma alimentar) ou nodal mediastinal (linfoma mediastínico), entretanto, ocasionalmente, outras apresentações bem menos comuns podem ser encontradas. O objetivo deste artigo é estabelecer a prevalência desses pouco usuais tipos de linfoma e demonstrar aos patologistas veterinários como eles se apresentam anatomopatologicamente. De um total de 100 casos de linfoma em cães diagnosticados entre os anos de 1965 e 2017, 16 casos (16/100) foram considerados como apresentações não tradicionais da doença: linfoma folicular (5/100), linfoma de células T periférico inespecífico (2/100), linfoma angiocêntrico (2/100), linfoma intravascular de grandes células T (2/100), granulomatose linfomatoide (2/100), linfoma de grandes células anaplásicas (1/100), linfoma hepatoesplênico de células T (1/100) e linfoma linfocítico crônico de pequenas células B - tipo intermediário (1/100). Esperamos que os resultados aqui demonstrados auxiliem patologistas veterinários a reconhecerem tais casos de "linfomas atípicos" em suas rotinas diagnósticas.(AU)
Asunto(s)
Animales , Perros , Linfoma/diagnóstico , Linfoma/patología , Linfoma/veterinariaRESUMEN
Lymphomas are the tumors most frequently associated with the death or euthanasia of dogs in most parts of the world. In dogs, they almost always occur as disseminated (multicentric lymphoma), gastrointestinal (alimentary lymphoma), or nodal mediastinal (mediastinal lymphoma) diseases. However, other uncommon presentations can occasionally occur. This study aimed to establish the prevalence of these unusual types of lymphoma and demonstrate to veterinary pathologists how they present pathologically. From a total of 100 cases of lymphoma in dogs diagnosed between 1965 and 2017, 16 cases (16/100) were considered by us as non-traditional presentations of the disease: follicular lymphoma, (5/100), peripheral T-cell lymphoma, NOS (2/100), angiocentric lymphoma (2/100), intravascular large T-cell lymphoma (2/100), lymphomatoid granulomatosis (1/100), anaplastic large-cell lymphoma (1/100), hepatosplenic T-cell lymphoma (1/100), and chronic small B-cell lymphocytic lymphoma, intermediate type (1/100). We hope that the results presented here can help veterinary pathologists to recognize such cases of "atypical lymphoma" in their diagnostic routines.(AU)
Linfomas são os tumores mais associados a morte ou eutanásia de cães na maior parte do mundo. Nessa espécie animal ocorrem quase sempre como uma doença disseminada (linfoma multicêntrico), gastrintestinal (linfoma alimentar) ou nodal mediastinal (linfoma mediastínico), entretanto, ocasionalmente, outras apresentações bem menos comuns podem ser encontradas. O objetivo deste artigo é estabelecer a prevalência desses pouco usuais tipos de linfoma e demonstrar aos patologistas veterinários como eles se apresentam anatomopatologicamente. De um total de 100 casos de linfoma em cães diagnosticados entre os anos de 1965 e 2017, 16 casos (16/100) foram considerados como apresentações não tradicionais da doença: linfoma folicular (5/100), linfoma de células T periférico inespecífico (2/100), linfoma angiocêntrico (2/100), linfoma intravascular de grandes células T (2/100), granulomatose linfomatoide (2/100), linfoma de grandes células anaplásicas (1/100), linfoma hepatoesplênico de células T (1/100) e linfoma linfocítico crônico de pequenas células B - tipo intermediário (1/100). Esperamos que os resultados aqui demonstrados auxiliem patologistas veterinários a reconhecerem tais casos de "linfomas atípicos" em suas rotinas diagnósticas.(AU)