Cytodiagnostics of canine lymphomas - possibilities and limitations

Malignant lymphomas are one of the most common malignant tumours occurring in dogs. The basic method of lymphoma diagnosis in human, as well as in canine oncology is histopathology supported by immunohistochemistry. It was suggested that in veterinary medicine excisional biopsy of lymph node and histopathology should be considered only where the cytologic diagnosis is equivocal or needs to be confirmed. There are at least three basic reasons for which cytological examination ought to be accepted as a sufficient and reliable diagnostic method for lymphoma in dogs. Firstly, most dog owners consider the fine-needle biopsy as an acceptable non-harmful method of sample collection. Secondly, an increasing number of studies recommend cytology as an accurate test for diagnosing and subtyping canine lymphoma. Finally, the vast majority of canine lymphoma subtypes belong to 4-5 categories characterized by a typical cytological picture. Immunocytochemical staining of cytological smears gives new diagnostic possibilities, such as detection of markers better characterizing given growth or a potential goal for target therapy in individual cases (for example inhibitors of platelet-derived growth factor).

Stathmin reduction and cytoskeleton rearrangement in rat nucleus accumbens in response to clozapine and risperidone treatment - Comparative proteomic study

The complex network of anatomical connections of the nucleus accumbens (NAc) makes it an interface responsible for the selection and integration of cognitive and affective information to modulate appetitive or aversively motivated behaviour. There is evidence for NAc dysfunction in schizophrenia. NAc also seems to be important for antipsychotic drug action, but the biochemical characteristics of drug-induced alterations within NAc remain incompletely characterized. In this study, a comprehensive proteomic analysis was performed to describe the differences in the mechanisms of action of clozapine (CLO) and risperidone (RIS) in the rat NAc. Both antipsychotics influenced the level of microtubule-regulating proteins, i.e., stathmin, and proteins of the collapsin response mediator protein family (CRMPs), and only CLO affected NAD-dependent protein deacetylase sirtuin-2 and septin 6. Both antipsychotics induced changes in levels of other cytoskeleton-related proteins. CLO exclusively up-regulated proteins involved in neuroprotection, such as glutathione synthetase, heat-shock 70-kDa protein 8 and mitochondrial heat-shock protein 75. RIS tuned cell function by changing the pattern of post-translational modifications of some proteins: it down-regulated the phosphorylated forms of stathmin and dopamine and the cyclic AMP-regulated phosphoprotein (DARPP-32) isoform but up-regulated cyclin-dependent kinase 5 (Cdk5). RIS modulated the level and phosphorylation state of synaptic proteins: synapsin-2, synaptotagmin-1 and adaptor-related protein-2 (AP-2) complex.

The animal-dependent risk factors in canine T-cell lymphomas

Malignant lymphomas are one of the most common malignancies occurring in dogs; among them T-cell tumours are less commonly recognized. Recently, many authors have recommended cytology as a sufficient diagnostic method for canine lymphomas, especially if supported by immunocytochemistry or flow cytometry. The aim of the study was to characterize animal-dependent risk factors in canine T-cell lymphomas (TCLs) in Poland, including specific cytological subtypes. Determination of the type and subtype of the tumour was made based on the updated Kiel cytological classification adopted for dogs as previously described. Two breeds turned out predisposed to TCL (dog de Bordeaux and Boxer) while no predisposition to B-cell lymphoma could be evidenced. Dogs with low-grade lymphoma were significantly older than those with high-grade lymphoma.

Epidemiological and morphological analysis of feline injection site sarcomas

Feline injection site sarcomas (FISS) are malignant neoplasms of mesenchymal origin which arise in sites of injections in cats. The prevalence is estimated between 1 in 1000 and 1 in 10 000 vaccinations in the United Kingdom. The aim of this study was to estimate the incidence of FISS in Poland and to analyse clinical aspects and histological and cytological features of injection site sarcomas. In our study the prevalence of FISS was 0.16% (16 FISS on 10.000 of cats) in feline patients in one of a veterinary surgery which conducts the general practice and 85 on 10.000 cats in a practice focused on veterinary oncology. The most typical microscopic features of FISS found in the present analysis were: the presence of perilesional scarring and inflammation, aggregates of lymphocytes at the tumour periphery, moderate but usually marked cellular pleomorphism and intralesional necrosis. The most typical cytologic features of FISS found in present study were: the presence of neutrophils, marked cellular pleomorphism, the presence of lymphocytes and macrophages, the presence of extremely large nuclei in the neoplastic cells, and high sample cellularity.

Large granular lymphoma in six cats

Large granular lymphomas (LGLs) comprise a specific group of lymphomas regardless of classifi- cation scheme. An LGL consists of cells that show less or more mature morphology, but typically neoplastic cells possess cytoplasmic azurophilic granules clearly visible during cytological examin- ation. The aim of the present study was to present clinical and cytological data on large granular lymphomas in cats and to analyses the therapeutic responses in treated cases. During the period from 2012 to 2014 six cats were as having large granular lymphoma. In one cat a nasal form of LGL was recognized, a systemic form was recognized in another cat, and in four cases an alimentary form was recognized. Cellular samples for cytopathology were collected from the cat with nasal cavity mass, from the enlarged mandibular lymph node and thoracic cavity from second cat, and in four cats from the abdominal mass during ultrasound-assisted fine-needle biopsy. Therapy was introduced in 5 of the 6 cats. In two cases palliative therapy with glucocorticoids was conducted, in two cases chemotherapy with COP protocol, and therapy with masitinib in one case. The median of survival time for cats treated with anticancer therapy was 9 months, the median of survival time for cats treated with glucocorticoids was 1.5 months. In conclusion, large granular lymphomas, especially the alimentary form, are a relatively common type of lymphoma in cats. Simple diagnostic methods such as clinical examination, imaging techniques and routine cytology are sufficient in majority of cases. Despite aggressive behavior and poor general prognosis, conventional chemotherapy lead to a good response in some treated cats regardless of anatomic form and histologic grade of malignancy.