Canine multicentric lymphomas are lymphoproliferative malignancies that have increased in recent decades. The patient’s treatment and prognosis are determined by the grade, histological type, and lymphoma immunophenotyping. To investigate the paraclinical signs and survival time in canines with different lymphoma immunophenotypes. Over 2 and a half years, 47 untreated dogs were diagnosed with multicentric lymphoma at the Veterinary School Hospital of Uruguay. The disease was clinically and cytologically diagnosed, and immunophenotyping was determined by flow cytometry. After the immunophenotyping, most of the patients were grouped into the following: B (LB), T aggressive (LTCD45⁺), or T-zone lymphoma (LTCD45⁻). The patients’ haematological values, calcemia, lactate dehydrogenase (LDH) levels, and plasmatic electrophoretic profiles were all determined immediately after that. Of all canine lymphomas, 55.3% were B, 31.9% were LTCD45⁺, and 10.6% were TCD45⁻. Only 2.2% were classified as nonB/nonT, and survival time differed between groups. Patients with LTCD45⁻ lymphomas had a mean life span of 641 days after diagnosis, followed by LB (166 days) and LTCD45⁺ (62 days). Red blood cell count, hematocrit, and hemoglobin levels did not differ between groups. However, the LTCD45⁻ group had significantly higher lymphocyte levels than the LTCD45⁺ and LB groups (p = 0.01 and 0.006, respectively). Levels of albumin, alpha-1, and alpha-2 globulins did not differ between groups. On the other hand, gamma globulins levels in the LTCD45⁻ were higher than in the other lymphoma groups. The presence of hypercalcemia and high plasma LDH levels were associated with patient severity. Only the TCD45⁺ group had hypercalcemia although both the LB and TCD45⁺ groups had elevations in LDH activity. Interestingly, there was a direct relationship between high LDH values (greater than 500 IU/l) and lower survival in TCD45⁺ lymphomas. Survival time and hematological and biochemical patterns differed among canine lymphomas immunophenotypes. Patients of LTCD45⁻ phenotype showed higher lymphocyte counts and gamma globulin levels and more prolonged survival. Serum LDH activity may provide additional prognostic information in high-grade T-cell lymphoma.

Background: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in dogs. It is characterized by the proliferation of neoplastic lymphocytes in the bone marrow, which are morphologically normal (mature), but non-functional. CLL in canines commonly originates in cytotoxic T lymphocytes (TCD8+), and although there is controversy regarding the prognostic value of the immunophenotype, this cell lineage may be associated with a good prognosis. Case description: A 10-year-old, entire female, mixed-breed dog was brought to the University Hospital of the Veterinary Faculty (UdelaR) for consultation because a routine pre-surgical check-up revealed lymphocytic leukocytosis, normocytic anemia, and hyperglobulinemia due to an oligoclonal gammopathy. The ultrasound revealed splenomegaly. PCR performed on blood was negative for Ehrlichia canis. Blood and bone marrow flow cytometry was performed to complement the diagnosis and carry out the immunophenotype, which showed CLL of CD8+ T-cell lineage. The clinical suspicion of CLL was confirmed by myelogram. Chemotherapy treatment based on alkylating agents and glucocorticoids was established. So far, the patient has an overall survival of 13 months with a good response to treatment. Conclusion: The combination of immunophenotyping test, the myelogram, and the hematological and biochemical profile confirmed the presence of T-CLL in our patient. Flow cytometry, increasingly used in veterinary medicine, allowed us to confirm the diagnosis of CLL originating in cytotoxic T lymphocytes in our patient, through the presence of positive staining of primary antibodies specific for the canine species CD45, CD3, CD5 and CD8 and the absence of staining for CD4, CD21 and CD34.

El carcinoma de células escamosas (CCE) es uno de los tumores cutáneos más frecuentes en la clínica equina, la presentación a nivel de globo ocular y anexos es de complejo abordaje terapéutico. Existen varios factores asociados al riesgo de desarrollar este tipo de neoplasia, como la exposición a los rayos UV, la despigmentación y la predisposición genética de ciertas razas. La recurrencia tumoral es frecuente luego de la cirugía oncológica y en ocasiones debe optarse por un tratamiento paliativo. El objetivo de este trabajo fue presentar el caso clínico de un padrillo paint horse con CCE palpebral, el cual fue tratado con electroquimioterapia (ECT) como monoterapia. El procedimiento fue realizado bajo anestesia general a campo y se llevaron a cabo controles clínicos a los 7, 15 y 45 días pos ECT para evaluar la respuesta a esta. Se observó una remisión completa del tumor a los 45 días después del procedimiento. En la actualidad, 24 meses después de la aplicación de la ECT, no se ha observado recidiva en el animal. Sin embargo, el pronóstico es reservado, debido a las características biológicas inherentes al tipo tumoral y a las posibilidades de recurrencia reportadas para esta neoplasia. El caso clínico presentado nos brinda a la ECT como una técnica alternativa a la cirugía oncológica en el CCE palpebral equino.

El linfoma es un tumor hematopoyético linfoide que representa una de las neoplasias malignas más comunes en equinos. Se describe un caso de linfoma en un caballo cuarto de milla, cuyo diagnóstico fue realizado post mortem tras el análisis histopatológico de los hallazgos de necropsia. Motivó la consulta la pérdida crónica de peso y diarrea de 24 horas de evolución. En el examen clínico se destacó una condición corporal 3/9, depresión, mucosas congestivas, fiebre, taquicardia, taquipnea y motilidad intestinal normal. Los análisis hematológicos y bioquímicos revelaron leucocitosis, linfocitosis, neutrofilia con desviación a la izquierda e hipoalbuminemia como las alteraciones más relevantes. Se realizó la eutanasia por falta de respuesta al tratamiento y necropsia 2 horas luego de la muerte del paciente. Se encontraron linfadenopatía y nódulos en la superficie del bazo, linfadenopatía en ciego y colon mayor. El estudio histopatológico reveló abundancia de linfocitos de aspecto tumoral, pleomórficos, anisocitosis, anisocariosis evidente y múltiples figuras mitóticas en bazo, ciego, colon, linfonódulos regionales y satélites. Las vellosidades y la lámina propia del ciego y el colon estaban invadidas de células tumorales. Se describe por primera vez en Uruguay un caso clínico-patológico de linfoma alimentario (tipo 5b, OMS) con manifestaciones en sangre, varios órganos y signos sistémicos. La inmunofenotipificación celular podría haber permitido un diagnóstico más preciso de la enfermedad.