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Canine urothelial carcinoma (UC) and prostate carcinoma (PC) frequently exhibit the BRAFV595E mutation, akin to the BRAFV600E mutation common in various human cancers. Since the initial discovery of the BRAF mutation in canine cancers in 2015, PCR has been the standard method for its detection in both liquid and tissue biopsies. Considering the similarity between the canine BRAFV595E and human BRAFV600E mutations, we hypothesized that immunohistochemistry (IHC) using a BRAFV600E‐specific antibody could effectively identify the canine mutant BRAFV595E protein. We tested 122 canine UC (bladder n = 108, urethra n = 14), 21 PC, and benign tissue using IHC and performed digital droplet PCR (ddPCR) on all 122 UC and on 14 IHC positive PC cases. The results from ddPCR and IHC were concordant in 99% (135/136) of the tumours. Using IHC, BRAFV595E was detected in 72/122 (59%) UC and 14/21 (65%) PC. Staining of all benign bladder and prostate tissues was negative. If present, mutant BRAF staining was homogenous, with rare intratumour heterogeneity in three (4%) cases of UC. Additionally, the BRAFV595E mutation was more prevalent in tumours with urothelial morphology, and less common in glandular PC or UC with divergent differentiation. This study establishes that BRAFV600‐specific IHC is a reliable and accurate method for detecting the mutant BRAFV595E protein in canine UC and PC. Moreover, the use of IHC, especially with tissue microarrays, provides a cost‐efficient test for large‐scale screening of canine cancers for the presence of BRAF mutations. This advancement paves the way for further research to define the prognostic and predictive role of this tumour marker in dogs and use IHC to stratify dogs for the treatment with BRAF inhibitors. [ABSTRACT FROM AUTHOR]

Urothelial carcinoma (UC) is the most common tumour of the canine urinary bladder. Recently, BRAF mutation testing emerged as a diagnostic option, but its prognostic significance is unknown. This study investigates the relationship between BRAF (variant V595E) mutation status and overall survival in UC‐bearing dogs. Seventy‐nine patients histologically diagnosed with UC of the bladder and/or urethra between 2006 and 2019 were included in this retrospective single‐centre‐study. Treatment consisted of meloxicam (n = 39, group 1 'Melox'), mitoxantrone and meloxicam (+/− followed by metronomic chlorambucil; n = 23, group 2 'Chemo') or partial cystectomy followed by meloxicam +/− mitoxantrone (n = 17, group 3 'Sx'). Survival was significantly influenced by treatment (p =.0002) and tumour location (p <.001) in both uni‐ and multivariable analyses. BRAF mutation was identified in 51 tumours (=64.6%) and had no statistically significant influence on overall survival: MST for BRAF‐negative patients 359 versus 214 days for BRAF‐positive dogs (p =.055). However, in BRAF‐positive dogs, survival depended significantly on type of treatment in univariable analysis: MSTs for groups 1–3 were 151, 244 and 853 days, respectively (p =.006); In BRAF‐positive group 2 ('Chemo')‐patients, adjuvant metronomic chlorambucil after mitoxantrone more than doubled MST compared to patients receiving mitoxantrone alone (588 vs. 216 days; p =.030). In contrast, MSTs were not significantly different in BRAF‐negative patients among the three treatment groups (p =.069). Multivariate analysis of these data was not possible due to group size limitations. This study identified tumour location and treatment type, but not BRAF mutation status, as independent prognostic factors for overall survival. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Forman et al (2021) have published a I Consensus Statement on Pancreatitis in Cats i , which covers information about etiology, pathophysiology, clinical findings, and therapy as well as clinical pathology and histopathology. The calculated specificity (74%) and sensitivity (mild pancreatitis: >3.5 g/L: 73.9%, >5.3 g/L: 56.5%; marked pancreatitis: >3.5 g/L: 81.8%, >5.3 g/L: 63.6%) in this study were comparable to specificities and sensitivities of fPLI in other articles. [Extracted from the article]