Tumour Incidence in Dogs in Germany: a Retrospective Analysis of 109,616 Histopathological Diagnoses (2014-2019).

Characterization of a tumour entity is based on the precise histopathological diagnosis taking into account the signalment of the diseased animal. The present study is a comprehensive, up-to-date statistical investigation on the type, frequency and breed distribution of neoplasia in dogs in Germany. The histopathological datasets of 109,616 German canine tissue samples (2014-2019) were processed and statistically examined in retrospect. Non-neoplastic diseases were found in 38,650 samples (35.3%) and 70,966 neoplasms (64.7%) were diagnosed. The most common neoplasms were mammary tumours (21.9%), benign epithelial skin tumours (15.4%), mast cell tumour (9.7%), histiocytoma (7.0%), soft tissue sarcoma (5.8%), lipoma (5.8%), melanocytic tumours (5.2%) and odontogenic tumours (4.7%). In general, Beagles, Magyar Vizslas, Boxers, Schnauzers, Spaniels, French Bulldogs and Golden Retrievers had an increased risk of neoplasia (odds ratio 1.17-1.46; all: P ≤0.001) compared with crossbreed dogs. In particular, Boxers, Golden Retrievers, Rottweilers and Schnauzers were often affected by malignant neoplasms, whereas some breeds (eg, West Highland White Terrier, Magyar Vizsla, Chihuahua, Dachshund and Yorkshire Terrier) were frequently affected by numerous benign tumour types. Despite the known risk of haemangiosarcoma in German Shepherd Dogs, other malignant tumours were rare in this breed. Depending on the type of tumour, some purebred dog breeds can have an increased, reduced or identical risk for certain neoplasms compared with crossbreeds. Discussion of breed predispositions to tumour diseases must therefore be conducted critically and with a view to clinical relevance.

Correlation of Histopathological Changes in the Left Atrium and Left Atrial Appendage with the Degree of Dilation in Cats.

Although atrial dilation is a common finding in feline cardiac disease, detailed investigations of atrial pathology are rare in cats. The aim of the study was to investigate the correlation between pathohistological findings, morphometric data and the degree of dilation of the left atrial appendage (LAA) in 53 cats. Based on the LAA volume, the samples were grouped into normal/control (group 0, ≤1 ml [n = 9]), mildly dilated (group 1, >1 to ≤2 ml [n = 16]), moderately dilated (group 2, >2 to ≤3 ml [n = 14]) and markedly dilated (group 3, >3 ml [n = 14]) groups, independent of the underlying disease. Samples from the LAA and the left atrium (LA) were histologically evaluated using haematoxylin and eosin- and Picrosirius red-stained sections, and morphometrically analysed using an image analysis system. The degree of endo-, myo- and epicardial fibrosis was directly correlated with increased LAA dilation. Due to cardiomyocyte hyperplasia and hypertrophy, the mean thickness of the atrial wall was significantly greater in groups 1 and 2 than in group 0. Conversely, group 3 had a lower mean atrial wall thickness than groups 1 and 2, which was attributed to increased transmural fibrosis and cardiomyocyte atrophy. These findings reflect intensive dynamic remodelling processes during LA and LAA dilation, indicating that reversibility appears to be limited in cases of severe left atrial dilation.

[Chronic bee paralysis virus - quo vadis? Incidence in Bavaria and consideration of therapeutic measures]. / Chronische-Bienenparalyse-Virus ­ quo vadis? Auftreten in Bayern und Betrachtung von Therapiemaßnahmen.

OBJECTIVE: Chronic bee paralysis virus (CBPV), a so far unclassified RNA virus that may cause neurological signs and hairless black syndrome in honey bees, has become increasingly prevalent in various European countries in recent years. The disease occasionally leads to immense losses of worker bees and a significant drop in performance, especially in strong colonies. The aim of this retrospective study was to analyse the spread of CBPV in Bavaria from 2018 to 2020 as well as to evaluate therapeutic measures. MATERIAL AND METHODS: In part 1 of the study, analysis results of the Tiergesundheitsdienst Bayern e. V. (Bavarian Animal Health Service) from 302 bee colonies were examined with regard to virus diagnostics and clinical signs with a focus on CBPV. In part 2, data collected with the help of a questionnaire regarding 105 CBPV-positive and symptomatic colonies were evaluated. RESULTS: In part 1, a significant (p = 0.004) increase in CBPV-positive samples from 2018 to 2020 was detected within Bavaria. In addition, the number of cases with clinical signs also increased during the last 2 years. Part 2 of the study showed a clustering of reports of initial onset of CBPV symptoms during springtime. The colonies mostly with a combination of symptoms recovered from the disease in 57 % of the cases. Therapeutic intervention was one decisive factor. A large number of different combinations of measures led to survival, and a lack of intervention mostly resulted in the death of the colony. In 62 % of the diseased and isolated colonies, isolation prevented further spread in the apiary. CONCLUSION UND CLINICAL RELEVANCE: Based on the results, CBPV occurred more frequently in connection with clinical signs in Bavaria in recent years. Due to the large number of applied combinations of measures, no evidence-based therapy recommendation may be derived based on the current evaluations. However, it has been shown that any therapeutic intervention is superior to withholding treatment. For precise therapy recommendations, trials with treatment under standard conditions are necessary.

Histopathological findings and canine pancreatic lipase immunoreactivity in normal dogs and dogs with inflammatory and neoplastic diseases of the pancreas.

BACKGROUND: Diagnosis of pancreatic diseases in dogs is still challenging because of variable clinical signs, which do not always correspond with clinical pathology and histopathological findings. OBJECTIVES: To characterize inflammatory and neoplastic pancreatic diseases of dogs and to correlate these findings with clinical findings and canine pancreatic lipase immunoreactivity (cPLI) results. ANIMALS: Tissue specimens and corresponding blood samples from 72 dogs submitted for routine diagnostic testing. METHODS: Four groups were defined histologically: (1) normal pancreas (n = 40), (2) mild pancreatitis (n = 8), (3) moderate or severe pancreatitis (acute, n = 11; chronic, n = 1), and (4) pancreatic neoplasms (n = 12). An in-house cPLI ELISA (<180 µg/L, normal; >310 µg/L, pancreatitis) was performed. RESULTS: In dogs with normal pancreas, 92.5% of serum cPLI results were within the reference range and significantly lower than in dogs with mild acute pancreatitis, moderate or severe acute pancreatitis and pancreatic tumors. In dogs with moderate or severe acute pancreatitis, cPLI sensitivity was 90.9% (95% confidence interval [CI], 58.7%-99.8%). Most dogs (9/12) with pancreatic tumors (group 4) had additional pancreatic inflammation and cPLI results were increased in 10 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: High cPLI indicates serious acute pancreatitis but underlying pancreatic neoplasms should also be taken into consideration. This study confirms the relevance of histopathology in the diagnostic evaluation of pancreatic diseases.

Evaluating the Histologic Grade of Digital Squamous Cell Carcinomas in Dogs with Dark and Light Haircoat-A Comparative Study of the Invasive Front and Tumor Cell Budding Systems.

Canine digital squamous cell carcinomas (CDSCC) are particularly aggressive when compared to their occurrence in other locations. Although these neoplasms are more frequently seen in dark-haired dogs, such as Giant Schnauzers, there are no data checking whether these tumors are histologically different between breeds. We histologically evaluated DSCC from 94 dogs. These were divided into two groups, namely, (1) dark-haired (N = 76) and (2) light-haired breeds (N = 18), further subdividing Group 1 into three subgroups, (1a) black breeds (n = 11), (1b) Schnauzers (n = 34) and (1c) black & tan breeds (n = 31). Adaptations from two different squamous cell carcinomas grading schemes from human and veterinary literature were used. Both systems showed significant differences when compared to Groups 1 and 2 in terms of final grade, invasive front keratinization, degree of invasion, nuclear pleomorphism, tumor cell budding, smallest tumor nest size and amount of tumor stroma. Group 2 was consistently better differentiated CDSCC than Group 1. However, there were no significant differences among the dark-haired breeds in any of the features evaluated. This study represents the first attempt to grade CDSCC while taking into account both phenotypical and presumptive genotypical haircoat color. In conclusion, CDSCC are not only more common in dark-haired dogs, they are also histologically more aggressive.

[Detection of BRAF mutation in canine prostatic diseases]. / Nachweis der BRAF-Mutation bei kaninen Prostataerkrankungen.

OBJECTIVE: In the literature, the BRAF mutation is reported to have been identified in 80 % of the examined canine prostate carcinomas (PCa). The objectives of this study were to test for the BRAF mutation in canine PCa in our cohort of canine patients, to determine the specificity and sensitivity of the test for this mutation, as well as to identify the association between the presence of the BRAF mutation and the histologic picture of PCa. Moreover, the method was to be established in cytology samples. MATERIAL AND METHODS: Biopsy samples (n = 70) and cytologic slides (n = 17) of 87 dogs with prostatic diseases were selected. Prostatic diseases were classified according to the literature as benign prostate hyperplasia (BPH, n = 22), prostatitis (n = 14), squamous cell metaplasia of the prostate (PM, n = 2), atrophy following castration (n = 3) und PCa (n = 46; histologic diagnosis n = 35, cytologic diagnosis n = 11). Additionally, the Gleason score was determined for each PCa. DNA isolation was performed using commercially available kits. Exon 15 was examined using the TaqMan® SNP assay. The specificity and sensitivity of the test were calculated. RESULTS: A Gleason score of 6 and 7 was shown in 1 PCa each, in 33 cases the score ranged between 8 and 10. Sufficient amount of good-quality DNA was isolated from all samples. 28/46 PCa were tested positive for the BRAF mutation (sensitivity 61 %). The BRAF mutation was not evident in any of the dogs with BPH, prostatitis, PM or atrophy (specificity 100 %). PCa positive for the BRAF mutation exhibited a significantly higher Gleason score (p = 0.002) in comparison to PCa without this mutation. CONCLUSION AND CLINICAL RELEVANCE: BRAF mutation analysis is a highly specific method and may aid in confirming the diagnosis of PCa in histologically and cytologically questionable cases. PCa positive for BRAF mutation exhibited more criteria of malignancy than PCa without this mutation. The clinical, therapeutic, and prognostic relevance of these findings needs to be evaluated by further studies.

Correlation of BRAF Variant V595E, Breed, Histological Grade and Cyclooxygenase-2 Expression in Canine Transitional Cell Carcinomas.

The presence of BRAF variant V595E, as well as an increased cyclooxygenase-2 (COX-2) expression in canine transitional cell carcinoma (TCC) are well-described in the literature. The aim of the present study was to investigate the correlation between breed (terrier versus non-terrier dogs), histological grade, COX-2 expression, and BRAF mutation in canine TCC. Therefore, transmural TCC biopsies from 65 dogs (15 terriers, 50 non-terriers) were graded histologically into low- and high-grade. Immunohistochemical evaluation of the intensity of COX-2 expression was performed using an immunoreactive score (IRS). Exon 15 of chromosome 16 was examined for the BRAF variant c.1799T>A by TaqMan® SNP assay. TCC was low-grade in 20 cases (one terrier, 19 non-terriers) and high-grade in 45 cases (14 terriers, 31 non-terriers). Contrary to humans, histological grade was not significantly correlated to the intensity of COX-2 expression. BRAF mutation was detected in 11/15 (73%) TCC of terriers and in 18/50 (36%) TCC of non-terriers. Histological grade and BRAF mutation were not correlated significantly (p = 0.2912). Terriers had a considerably higher prevalence of high-grade tumors (p < 0.0001), as well as of BRAF mutation (p ≤ 0.05) compared to non-terriers. In non-terriers, neoplasms with BRAF mutation showed a significantly higher intensity of COX-2 expression than those without BRAF mutation (p ≤ 0.05). In conclusion, in contrast to humans, testing for BRAF mutation in canine TCC is a sensitive diagnostic method especially in terriers (73%) and may be recommended as a screening test. However, evidence of BRAF mutation in canine TCC is not a predictor for the histological grade. Moreover, a positive correlation between histological grade and the intensity of COX-2 expression was not found. Further studies are necessary to clarify the clinical and prognostic relevance of the elevated intensity of COX-2 expression of TCC with BRAF mutation detected in non-terriers.