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Canine osteosarcoma (OS) is an aggressive bone tumor with high metastatic potential and poor prognosis, mainly due to metastatic disease. Nanomedicine-based agents can be used to improve both primary and metastatic tumor treatment. Recently, gold nanoparticles were shown to inhibit different stages of the metastatic cascade in various human cancers. Here, we assessed the potential inhibitory effect of the glutathione-stabilized gold nanoparticles (Au-GSH NPs) on canine OS cells extravasation, utilizing the ex ovo chick embryo chorioallantoic membrane (CAM) model. The calculation of cells extravasation rates was performed using wide-field fluorescent microscopy. Transmission electron microscopy and Microwave Plasma Atomic Emission Spectroscopy revealed Au-GSH NPs absorption by OS cells. We demonstrated that Au-GSH NPs are non-toxic and significantly inhibit canine OS cells extravasation rates, regardless of their aggressiveness phenotype. The results indicate that Au-GSH NPs can act as a possible anti metastatic agent for OS treatment. Furthermore, the implemented CAM model may be used as a valuable preclinical platform in veterinary medicine, such as testing anti-metastatic agents.

Introduction Appendicular osteosarcoma (OSA) is a highly aggressive and metastatic primary bone tumour in dogs. Standard therapy is amputation and adjuvant chemotherapy (e.g. with doxorubicin). Liposomal drug delivery may augment therapeutic efficacy and reduce negative side effects. Polyethylene glycol (PEG)-liposomal doxorubicin treats human metastatic cancers effectively. The study aimed was to evaluate PEG-liposomal doxorubicin’s inhibitory effect on canine metastatic proliferation and migration in vitro. It also aimed to appraise the drug’s extravasation inhibition in vivo using the human medicine–proven chick embryo chorioallantoic membrane ex ovo model. Material and Methods The canine D-17 OSA cell line was cultured and inoculated with decreasing concentrations of PEG-liposomal doxorubicin and conventional doxorubicin in a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test of cell viability, proliferation and cytotoxicity. Flow cytometry with Annexin V and Draq 7 staining confirmed the MTT test results, indicating dead, early and late apoptotic, and live cells. The inhibitory effect of the two preparations on cancer cell migration was investigated with a wound-healing assay. Culture plates seeded with cells were prepared. The cell monolayer was scratched and images of cells migrating to the scratch were captured at 0 h, 12 h and 24 h. Also, embryos were removed from three-day-incubated fertilised chicken eggs. On the 12th day, labelled D-17 cells were injected into each embryo. Embryos in one group received 100 μL of phosphate-buffered saline as controls, those in another group 30 μg/mL of PEG-liposomal doxorubicin, and those in the last group 6 μg/mL of conventional doxorubicin. The effectiveness of the intravascular administration of the D-17 cells was confirmed under a microscope. Results PEG-liposomal doxorubicin inhibited the migration of canine OSA cells more effectively than conventional doxorubicin (P ≤ 0.05). The ex ovo model showed that both drugs had similar impacts on canine metastatic OSA. Conclusion The liposomal form of the drug may be considered a potentially effective compound in canine metastatic OSA; nevertheless, further in vivo studies are essential to confirm this hypothesis.

The chick chorioallantoic membrane (CAM) assay has long been used to study the effects of drugs on angiogenesis or evaluate cancer cell invasiveness by quantifying in vivo rates of cancer cell extravasation. Extravasation plays a crucial role in the metastatic cascade, whereby circulating cancer cells derived from the primary tumor cross the endothelial barrier to reach the target metastatic site. Accordingly, we adapted an ex ovo model to study the anti-extravasation efficiency of anticancer drugs. The drugs investigated include conventional and PEG-liposomal doxorubicin. The conventional form is commonly used in chemotherapy protocols for canine appendicular osteosarcoma (OSA), although it has no specific biodistribution and a low therapeutic index. For this reason, this study compared the effects of conventional and PEG-liposomal doxorubicin on cytotoxicity and migration inhibition in the in vitro environment. Cytotoxicity was evaluated by the MTT assay, Annexin V staining and the Draq 7 test; the inhibition of migration was analyzed using the scratch assay test. Moreover the inhibitory effect of study drugs on cancer cell extravasation was analyzed in the in vivo conditions, on the ex ovo model. The results of experiments performed showed that PEG-liposomal doxorubicin has a higher inhibitory effect on the in vitro migration of canine OSA (p ≤ 0.05). Ex ovo research revealed both drugs elicited a high efficiency for inhibiting the extravasation of canine OSA (p< 0.0001). Therefore PEG-liposomal doxorubicin may be considered as a potentially useful anti-metastatic agent in canine osteosarcoma due to its inhibitory effect on both the migration and extravasation of the D-17 cell line.

Osteosarcoma (OSA) is the most common malignant bone neoplasia in humans and dogs. In dogs, treatment consists of surgery in combination with chemotherapy (mostly carboplatin and/or doxorubicin (Dox)). Chemotherapy is often rendered ineffective by multidrug resistance. Previous studies have revealed that Dox conjugated with 4 nm glutathione-stabilized gold nanoparticles (Au-GSH-Dox) enhanced the anti-tumor activity and cytotoxicity of Dox in Dox-resistant feline fibrosarcoma cell lines exhibiting high P-glycoprotein (P-gp) activity. The present study investigated the influence of Au-GSH-Dox on the canine OSA cell line D17 and its relationship with P-gp activity. A human Dox-sensitive OSA cell line, U2OS, served as the negative control. Au-GSH-Dox, compared to free Dox, presented a greater cytotoxic effect on D17 (IC50 values for Au-GSH-Dox and Dox were 7.9 μg/mL and 15.2 μg/mL, respectively) but not on the U2OS cell line. All concentrations of Au-GSH (ranging from 10 to 1000 μg/mL) were non-toxic in both cell lines. Inhibition of the D17 cell line with 100 μM verapamil resulted in an increase in free Dox but not in intracellular Au-GSH-Dox. The results indicate that Au-GSH-Dox may act as an effective drug in canine OSA by bypassing P-gp.

In a 9-years-old Labrador retriever, signs of severe weakness and a dark brown colour of urine were observed. During clinical examination, pain of the abdominal cavity and muscles was noted. Abdominal x-ray and ultrasound examination revealed signs of intestinal obstruction. The activity of creatine kinase was 187380 U/l. The diagnosis of acute muscle damage was made. Treatment included antibiotic and analgesic therapy, as well as aggressive fluid infusion. No additional treatments were required, and the dog made a speedy recovery. The rapid and intensive treatment prevented acute renal failure, which is a life-threatening complication of acute rhabdomyolisis. This is the first case of acute idiopathic rhabdomyolysis in a dog in Poland. An early intensive fluid therapy and a critical interpretation of radiological signs of intestinal obstruction are crucial for successful therapy.

Proteomic analyses are rapid and powerful tools that are used to increase the understanding of cancer pathogenesis, discover cancer biomarkers and predictive markers, and select and monitor novel targets for cancer therapy. Feline injection-site sarcomas (FISS) are aggressive skin tumours with high recurrence rates, despite treatment with surgery, radiotherapy, and chemotherapy. Doxorubicin is a drug of choice for soft tissue sarcomas, including FISS. However, multidrug resistance is one of the major causes of chemotherapy failure. The main aim of the present study was to identify proteins that differentiate doxorubicin-resistant from doxorubicin-sensitive FISS using two-dimensional gel electrophoresis (2DE), followed by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Using the three-dimensional (3D) preclinical in ovo model, which resembles features of spontaneous fibrosarcomas, three significantly (p ≤ 0.05) differentially expressed proteins were identified in tumours grown from doxorubicin-resistant fibrosarcoma cell lines (FFS1 and FFS3) in comparison to the doxorubicin-sensitive one (FFS5): Annexin A5 (ANXA5), Annexin A3 (ANXA3), and meiosis-specific nuclear structural protein 1 (MNS1). Moreover, nine other proteins were significantly differentially expressed in tumours grown from the high doxorubicin-resistant cell line (FFS1) in comparison to sensitive one (FFS5). This study may be the first proteomic fingerprinting of FISS reported, identifying potential candidates for specific predictive biomarkers and research targets for doxorubicin-resistant FISS.

Combination chemiotherapy is the current standard of care for dogs with lymphoma. Multidrug resistance is one of the most important factors contributing to the efficacy of chemiotherapy. The major protein responsible for this phenomenon is P-glycoprotein. Little is known about P-glycoprotein expression in particular subtypes of lymphomas. The aim of the study was evaluation of P-glycoprotein expression in various subtypes of canine lymphomas. Positive reaction with P-glycoprotein was found in 12/25 cases of various morphological subtypes of lymphomas, however, in 3/11 lymphomas the percentage of positively weakly stained cells was

Survivin is a member of apoptosis inhibiting proteins family. Apart from its antiapoptotic activity it plays a critical role in regulating the cell cycle and mitosis. It is overexpressed in most human malignancies. While the prognostic significance of survivin expression is widely investigated in human non-Hodgkin's lymphomas, little is known about its expression in canine lymphomas. The aim of the study was to evaluate the expression of survivin in canine lymphomas in relation to proliferation markers (mitotic index and percentage of Ki67-positive cells). Survivin was found in all examined lymphomas belonging to 6 different morphological subtypes with nuclear immunoreactivity. In most of lymphomas (18/25) survivin expression ranged 10%-25% of positive cells. Only single cases had lower (0-10% positive cells, 1/25) or higher (25-50% and >50% positive cells, 5/25 and 1/25, respectively) index of survivin. Neither mitotic index nor proliferative index correlated with survivin expression when the values quantified randomly in whole specimens were compared. However, when survivin expression were quantified in selected tumor areas of low and high proliferation activity the high correlations between survivin expression and proliferation index were found. The results indicated that survivin is commonly expressed in canine lymphomas. Nuclear labelling together with the relation of its expression and proliferative activity in highly proliferative areas of neoplastic tissue suggest a potential role of survivin in cell cycle activation in canine lymphoma cells. However, further studies of the relation between expression of survivin and other proteins involved in cell cycle regulation are needed. Moreover, the results suggest that survivin may pose the therapeutic target in canine lymphomas.

The chick embryo chorioallantoic membrane (CAM) model is extensively used in human medicine in preclinical oncological studies. The CAM model has several advantages: low cost, simple experimental approach, time saving and following “3R principles”. Research has shown that the human osteosarcoma cell lines U2OS, MMNG-HOS, and SAOS can form tumors on the CAM. In veterinary medicine, this has been described only for feline fibrosarcomas, feline mammary carcinomas and canine osteosarcomas. However, in case of canine osteosarcomas, it has been shown that only non-adherent osteosarcoma stem cells isolated from KTOSA5 and CSKOS cell lines have the ability to form microtumors on the CAM after an incubation period of 5 days, in contrast to adherent KTOSA5 and CSKOS cells. In the presented study, we have proven that the commercial adherent canine osteosarcoma cell line (D-17) can form vascularized tumors on the CAM after the incubation period of 10 days.

Osteosarcoma (OSA) is the most common type of bone tumors in dogs, which has high metastasis ability. 80 % of dogs with OSA die due to lung metastasis. As a result its treatment is a challenge for veterinary practitioners. The authors discuss the etiology, pathogenesis and the possible risk factors of OSA. The article focuses on literature review and the study of recent advances in OSA treatment. The authors describe therapies which have significantly prolonged the lives of dogs, as well as those that have proven to be ineffective. Advantages and disadvantages of limb amputation and limb-sparing surgery have been described. Authors present also the results of both single agent's therapies with the most commonly used drugs as cisplatin, carboplatin and doxorubicin and compare them to the results obtained using combined chemotherapy. The use of nanotechnology as a new approach in OSA treatment in order to avoid multidrug resistance and reduce negative side effects of cytostatic drugs is presented. The main reasons of the therapies failure are also provided in this article.

The purpose of this study was to assess the prevalence of feline hyperthyroidism in a cat population in Warsaw, considering risk factors. The study was conducted between June 2007 and July 2011. Seven-year-old and older cats were examined. Diagnosis of feline hyperthyroidism was based on the results of clinical examination, data from clinical history, and serum concentrations of thyroid hormones. Hyperthyroidism was diagnosed in 20.14% of 417 cats (95% confidence interval (CI): 16.28%-24.01%). Statistically significant risk factors were age (odds ratio (OR) = 1.17; 95% CI: 1.08-1.27), feeding with a commercial wet feed (OR = 6.74, 95% CI: 2.03-22.37), and an indoor lifestyle (OR = 2.25, 95% CI: 1.04-4.84). There were no effects of breed, gender, castration, or the frequency of deworming on the occurrence of hyperthyroidism. Feline hyperthyroidism in Warsaw is a prevalent disease. This probably results from chronic exposure to dietary and environmental factors.

Morphological lesions in hepatic stellate cells caused by the immunosuppressive doses of dexamethasone were investigated in dogs. The archival samples of liver collected during a surgical biopsy were examined. The samples were fixed in 10% buffered formalin or Carnoy’s solution and then stained with routine histochemical methods. The lesions were also investigated under electron microscope. It was demonstrated that the number of stellate cells significantly increased (P = 0.0277), yet the size of cytoplasmic lipid droplets significantly decreased (P = 0.0001). Even though steroid-induced hepatopathy is considered to be a reversible pathology, and the lesions in hepatocytes under the influence of dexamethasone occur in a short period, it was found that hepatic stellate cells proliferated and underwent activation. This resulted in collagen accumulation in the hepatic sinuses. The functional and morphological disturbances in the canine liver in the course of steroid-induced hepatopathy are initially subclinical, but the changes in the structure and function of hepatic stellate cells may become a cause of lesions in the wall of hepatic sinusoidal vessels, which may induce additional functional pathologies unrelated to the damage to hepatocytes.

Forty five lymphomas, 14 of T cell origin, 28 of B cell and 3 with null-cell phenotype, were included in this study. Tumors were classified according to the updated Kiel classification system adapted to canine lymphomas. The percentage of Ki67+ cells and mitotic index (MI) were estimated in each specimen. Most of lymphomas (39 of 45) had high proliferation activity. Among them in 27 cases 50-70% of lymphoma cells expressed Ki67, the highest Ki67 expression (>70% Ki67+cells) was identified less frequently, in 12 cases. Moderate Ki67 expression (20-50% positive cells) was observed in 5 cases, only one tumor had low Ki67 expression (vs. 3.33). Moreover, high positive correlation between the expression of Ki67 and MI was found (r = 0.668; P ≤ 0.001). In T-cell tumors the correlation was very high (r = 0.83; P ≤ 0.001) and in B-cell lymphomas the correlation was high (r = 0.61; P ≤ 0.001). There were also differences between mean MI values in the lymphomas of different morphological subtypes, but in some of them high variations in the range of MI values were identified and wide overlaps of MI between individual cases from different subtypes were observed. Because of differences in the proliferation activity in single cases of the same subtype of lymphoma, the proliferation activity assessment may be helpful to chose appropriate scheme of treatment and should be commonly performed during routine histopathological diagnosis of canine lymphomas.

Feline injection site sarcomas (FISS) are malignant skin tumors with high recurrence rates despite the primary treatment of radical surgical resections. Adjunctive radiotherapy or chemotherapy with doxorubicin is mostly ineffective. Cellular and molecular causes of multidrug resistance, specific physio-chemical properties of solid tumors impairing drug transport, and the tumor microenvironment have been indicated for causing standard chemotherapy failure. Gold nanoparticles are promising imaging tools, nanotherapeutics, and drug delivery systems (DDS) for chemotherapeutics, improving drug transport within solid tumors. This study was conducted to assess the distribution of 4-nm glutathione-stabilized gold nanoparticles in FISS and their influence on kidney and liver parameters in nude mice. The role of gold nanoparticles as a doxorubicin DDS in FISS was examined to determine the potential reasons for failure to translate results from in vitro to in vivo studies. Grade III tumors characterized by a large area of necrosis at their core displayed positive immuneexpression of tumor-associated macrophages (TAM) at both the periphery and within the tumor core near the area of necrosis. Gold nanoparticles did not cause necrosis at the injection site and had no negative effect on liver and kidney parameters in nude mice. Gold nanoparticles accumulated in the tumor core and at the periphery and co-internalized with TAM—an important observation and potential therapeutic target warranting further investigation. The large area of necrosis and high immunoexpression of TAM, indicating “pro-tumor macrophages”, may be responsible for FISS tumor progression and therapeutic failure. However, further studies are required to test this hypothesis.

Hepatic stellate cells play a crucial role in the development of liver fibrosis. In a damaged liver, stellate cells undergo activation, which is manifested as a change of their phenotype: differentiation of stellate cells to myofibroblast-type cells, expression of alpha-Smooth Muscle Actin, their proliferation and a reduction in the size of cytoplasmic lipid droplets. The aim of this study was to determine the number and morphology of stellate cells in the canine liver affected by congenital portosystemic shunt (PSS) and portal vein hypoplasia – hepatic microvascular dysplasia (PVH-HMD). The material for investigation were archived paraffin blocks with liver samples collected supravitally from six dogs with PSS, six dogs with PVH-HMD and six healthy dogs. On the HE-stained sections, the number of stellate cells per 100 hepatocytes was counted (Sztark method) and the diameter of veins in the hepatic triads was measured (light microscope Olympus BX 43, SC30 camera, CellSens Entry 2011 Olympus). In addition, the diameter of lipid droplets in stellate cells was measured (computed image analysis system LUCIA 4.21). The results were analysed statistically (the Kruskal-Wallis test followed by Dunn’s post-hoc procedure; significance level (α) at 0.05; Statistica 12 StatSoft Inc.). The degree of liver fibrosis was determined (Masson’s method of slide stain; Scheuer scale). The liver samples from the dogs with PSS and PVH-HMD were stained immunohistochemically with Monoclonal Mouse Anti-Human Smooth Muscle Actin (α-SMA), clone 1A4, antibodies (DAKO). Portosystemic shunt and primary portal vein hypoplasia in the dog results in a reduction in the diameter of portal vein branches and in insufficient portal blood flow through the liver. In the material investigated, this was particularly evident in the animals affected by PSS: such dogs had a significantly smaller diameter of the veins than did the healthy dogs (p

Lymphoma is one of the most common malignant tumours occurring in dogs. Since there is a constant need for new, more comprehensive laboratory diagnostic tools which permit the precise determination of many tumour-related factors we decided to verify whether the use of microarray analysis could be helpful in classifying lymphomas. The study was performed on samples collected from 7 dogs in which multicentric lymphoma was recognized. Among this group we were able to identify one sub-cluster of transcriptionally similar tumours, which completely differed in terms of the histopathological examination. Among them there were one diffuse large B cell lymphoma, one diffuse macronucleolated medium-sized cell lymphoma and one pleomorphic mixed small and large T-cell lymphoma. The lymphomas belonging to the sub-cluster differed from other analysed tumours in the expression of more than 100 genes of which only 18 were described earlier in regard to lymphomas.

An 11-year-old, 24-kg, intact female Siberian husky dog in anestrus had a 2-month history of polyuria and polydipsia. The dog had signs of mineralocorticoid excess such as hypertension and hypokalemia refractory to potassium supplementation. Abdominal ultrasound revealed an irregular mass in the left adrenal gland. The ACTH stimulation test for aldosterone concentration did not reveal hyperaldosteronism. Unilateral adrenalectomy was performed and histopathology identified adrenal cortical carcinoma. All clinical signs of mineralocorticoid excess ceased after surgery.

Immunohistochemical study of expression of immunoglobulins in canine B-cell lymphomasNineteen canine lymphomas were included in this study. Tumors were classified according to the updated Kiel classification adapted for canine lymphomas by Fournel-Fleury et al. Immunoglobulin light chains (κ and λ) and IgM and IgG expression were determined by immunohistochemical method. In all examined cases neoplastic cells were positive for one of the immunoglobulin light chains. Expression of λ light chains and κ light chains was observed in 18/19 and 1/19 tumors, respectively. In the majority of neoplastic cells in each examined specimen this reaction had a membranous pattern (sκ/sλ). In all examined cases the presence of immunoglobulin light chains was also observed in the cytoplasm of some neoplastic cells (cκ/cλ). These cells were usally rare and never constituted a dominant population. The expression of immunoglobulin was found in 13/19 cases. Most lymphomas were sIgM positive (11/13 cases). In one case expression of IgG was found, and in another lymphoma two populations of neoplastic cells with different expression of examined immunoglobulins (cells with IgM+and IgG+phenotypes) were observed. The reaction also had a membranous pattern. The cells containing cytoplasmic immunoglobulins were rare, and in most cases were of the same type as the surface immunoglobulins. Our study has confirmed that canine lymphomas are a monoclonal proliferation of B-cells usually expressing immunoglobulin λ light chains and that the vast majority of tumors deriving from B-cells express IgM. Our study also indicates a possibility of occurence of biclonal lymphomas in canine species.

An 8-year-old, spayed female, mixed breed dog diagnosed with hyperadrenocorticism and treated with trilostane for 13 days was presented to the clinic due to vomiting, shaking, and weakness. The ACTH stimulation test and electrolyte analysis confirmed hypoadrenocorticism. Treatment with prednisolone and fludrocortisone gave good results, however long lasting exogenous glucocorticoid administration led to a decrease in total and free thyroxine concentrations and caused clinical signs of hypothyroidism, such as lethargy and reduced appetite. The authors suspected euthyroid sick syndrome. After sixteen months therapy with prednisolone and fl udrocortisone ACTH stimulation tests still revealed low plasma cortisol concentrations in this dog, which suggested persistent hypoadrenocorticism. To the authors’ knowledge there have only been a few cases in which canine iatrogenic persistent hypoadrenocorticism or hypocortisolism was described after short term treatment with trilostane. However, in the previous cases the longest duration of hypocortisolism was 12 months., Kastrirana kuja, mješanka, u dobi od osam godina, s prethodno dijagnosticiranim hiperadrenokorticizmom, liječena trilostanom 13 dana, bila je dovedena na kliniku zbog povraćanja, drhtanja i slabosti. Podražaj ACTH-om i analiza elektrolita potvrdili su da je riječ o hipoadrenokorticizmu. Liječenje prednizolonom i fludrokortizonom dalo je dobre rezultate. Ipak dugotrajno davanje egzogenog glukokortikoida dovelo je do smanjenja koncentracije ukupnog i slobodnog tiroksina te je uzrokovalo kliničke znakove hipotiroidizma kao što su letargija i smanjeni apetit. Autori su posumnjali na eutiroidni sindrom. Nakon 16 mjeseci terapije prednizolonom i fludrokortizonom, ACTH podražajni testovi pokazivali su još uvijek nisku koncentraciju kortizola u plazmi te kuje što je upućivalo na perzistentni hipoadrenokorticizam. Dosada je opisano svega nekoliko slučajeva jatrogenoga perzistentnoga hipoadrenokorticizma ili hipokortizolizma nakon kratkotrajne primjene alostana. U prijašnjim slučajevima hipokortizolizam je najduže trajao 12 mjeseci.

The REQUEST Group comments: When nine European veterinarians met together three years ago, they didn't have the faintest idea of what would come out of the meeting. They knew only that too many self-endorsed ‘spokespersons’ were asserting what should be the proper use of fluoroquinolones among companion animals without any clear rationale. The objective of the meeting was to appraise the available literature on the use of fluoroquinolones among companion animals and to find out …

Studies were conducted on four giraffe (Giraffa camelopardalis) with diarrhea and three clinically healthy ones. The feces from both healthy and sick animals were examined to determine amylase, lipase and trypsin activity. In the feces of the giraffe with diarrhea a significant decrease of amylase and lipase activity was noted. The trypsin activity remained unchanged. Pancreatic exocrine insufficiency-like syndrome was diagnosed on the basis of laboratory investigations and histopathological examinations. The administration of pancreatic enzyme supplements (Pancreatin; Polfa, Poland) had a noticeable effect on the normalization of clinical state and laboratory data of the giraffe with diarrhea. Determination of amylase and lipase activity in the feces may be helpful in determination of the condition of the pancreas in the course of chronic diarrhea in giraffe.

Feline vaccine associated fibrosarcomas are the second most common skin tumor in cats. Methods of treatment are: surgery, chemotherapy and radiotherapy. Nevertheless, the usage of cytostatics in feline vaccine associated sarcoma therapy is limited due to their adverse side effects, high toxicity and low biodistribution after i.v. injection. Therefore, much research on new therapeutic drugs is being conducted. In human medicine, the chick embryo chorioallantoic membrane (CAM) model is used as a cheap and easy to perform assay to assess new drug effectiveness in cancer treatment. Various human cell lines have different tumors growth on CAM. In veterinary medicine such model has not been described yet. In the present article derivation of feline vaccine associated fibrosarcoma cell line and its growth on CAM is described. The cell line and the tumor grown were confirmed by histopathological and immunohistochemical examination. As far as we believe, this is the first attempt to create such model, which may be used for further in vivo studies in veterinary oncology.

SummaryFeline cutaneous paraneoplastic syndrome is a rare disorder associated mainly with pancreatic carcinoma and thymoma. In this report the authors describe the case of a 12-year-old cat with paraneoplastic exfoliative dermatitis associated with thymoma. Lateral radiographic examination of the chest showed a small subtle soft tissue density in the ventral part of the first and second intercostal space, which together with skin changes suggested thymoma. Because of pain associated with the skin condition, costs of treatment and the risk associated with surgical treatment, the owner chose euthanasia of the cat. Post-mortem examination revealed a tumour which was diagnosed as thymoma by histopathological examination.