Search

The objective of this study was to investigate the immunolabelling of acetylated histones and histone desacetylase (HDAC) enzymes in canine soft tissue sarcomas (STSs) and to correlate them with histological and clinical features in order to identify possible prognostic and therapeutic targets in these neoplasms. Fifteen canine STS samples were evaluated and were submitted to immunohistochemistry for acetylated histones 3 (H3) and 4 (H4) and deacetylating enzymes (HDAC1, HDAC2 and HDAC6). Intense immunolabelling of H4 was seen in comparison with H3. A strong positive correlation was observed between the H3 intensity score and the number of mitotic figures (P = 0.004, r = 0.7). Intense immunolabelling of HDAC1 was found in comparison to the expression of HDAC2 and HDAC6 in the evaluated STSs. This finding suggests that HDAC1 may be a potential target for HDAC inhibitors in STSs in dogs.

Objectives The aim of this study was to establish the safety and efficacy of a novel multidrug lomustine-based chemotherapeutic protocol for cats with high-grade multicentric or mediastinal lymphoma, in an area endemic for feline leukemia virus (FeLV). Methods This prospective study included owned cats, diagnosed (cytologically) with multicentric or mediastinal lymphoma and treated with the LOPH (lomustine, vincristine [Oncovin; Antibióticos do Brasil], prednisolone and hydroxydaunorubicin [doxorubicin]) protocol. A complete blood count was performed before every chemotherapy session and any significant abnormalities recorded as possible related toxicities. Median survival time (MST) and disease-free interval were estimated by Kaplan–Meier curves. Results Twenty-one cats were included in this study. Nineteen (90.5%) tested positive for FeLV and were therefore considered to have persistent viremia. Complete response was reported in 81% (n = 17/21), while three had partial remission and one had no response. Seven cats finished the induction protocol within 20–31 weeks (23.1 ± 4.5; median 20) and all seven received a maintenance protocol. The MST (lymphoma-related survival) for the 21 cats was 214 days. The MST was 214 days for cats with mediastinal lymphoma (n = 13), but it was not reached for multicentric lymphoma (n = 8; P = 0.9). The MST of cats with persistent FeLV antigenemia was 171 days. Grade I anorexia and vomiting occurred in 19% of the cats (n = 4/21). Hematologic toxicity was found in 100% of the cats at some point during their treatment, but it was mostly grade I or II. Neutropenia, thrombocytopenia and anemia occurred in 16/21, 21/21 and 15/21 cats, respectively. Conclusions and relevance The LOPH protocol was well tolerated by cats with lymphoma and persistent FeLV viremia, and resulted in a better MST than similar studies with other protocols. Novel studies and controlled trials are necessary in order to evaluate the efficacy of different protocols according to the lymphoma subtype, anatomic form and FeLV status.

Seven juvenile broad-snouted caiman (Caiman latirostris), bred in captivity and subjected to a diet deficient in minerals and vitamins during the first months of life, developed intense cachexia and generalized loss of bone stiffness. In a histopathological evaluation, the proliferation of stellate elongated cells with scarce and eosinophilic cytoplasm in the middle of a loose fibrillar and eosinophilic extracellular matrix was observed, especially in the long bones, which was compatible with fibrous osteodystrophy. Diffuse disorganization of the chondrocyte columns of the endochondral ossification zones with a light multifocal presence of dilated blood capillaries characterized rickets. The bone marrow of the animals revealed intense replacement of active myeloid tissue with adipose tissue and rare promyelocytes, which were compatible with marrow aplasia. Additionally, caseous lesions were evident in the lungs of three animals and the histopathological findings and microbiological analysis were compatible with a bacterial pneumonia. The present work gives a detailed anatomopathological description of the case.