Case summary A 5-month-old entire male domestic shorthair kitten was referred for investigation of a month-long history of urinary incontinence. Clinical examination, baseline blood work and imaging (plain radiography and ultrasonography) were unremarkable. Urinalysis documented a urinary tract infection and a retrograde urethrocystogram revealed an outpouching of the pelvic urethra. Surgical exploration revealed the absence of the dorsal portion of the urethral wall in this section of pelvic urethra, replaced by an epithelial lined expanded ‘pouch’. The ventral aspect of the urethra appeared grossly normal. A modified perineal urethrostomy was performed to create an anastomosis of the urethral pouch to the skin of the perineum alongside conventional castration. The kitten made a full recovery and the incontinence resolved within 48 h. A congenital urethral diverticulum and secondary urinary tract infection were deemed the most likely aetiology in this case. Relevance and novel information Urethral diverticuli are a rare condition in veterinary medicine. To our knowledge, it has only been reported in two dogs and presumptively in one cat, all of which made a complete recovery after surgical intervention. The present case reports an unusual urethral deformity as a potential differential diagnosis for lower urinary tract signs in a young cat.

Objectives Serum amyloid A (SAA) concentrations are increased in cats with lymphoma vs healthy cats; however, the association between SAA concentrations and prognosis in cats with lymphoma is unclear. The aim of this study was to evaluate if SAA concentrations were different in cats with nasal vs non-nasal lymphoma, if SAA concentrations are prognostic in patients treated with high-dose chemotherapy and if SAA concentrations are correlated with other clinicopathological variables. Methods Cats diagnosed with intermediate- or large-cell lymphoma between 2012 and 2022 with SAA concentration data available were included. Associations between tumour site (nasal vs non-nasal), stage, response to treatment and SAA concentration were evaluated using non-parametric statistics. Associations between SAA concentrations and stage with survival time were evaluated using Cox regression analysis. Patients with nasal tumours and those not receiving high-dose chemotherapy were excluded from the survival analyses. Results Thirty-nine cats were included. Median SAA concentrations were significantly higher in non-nasal compared with nasal lymphoma (42 µg/ml [range <0.3–797] vs <0.3 µg/ml [range <0.3–0.9]; P = 0.026). SAA concentrations did not correlate with tumour stage. Median survival time for patients with non-nasal tumour and undergoing chemotherapy was 49 days (range 2–1726). Responders had a better median survival time than non-responders (273 days [range 43–1728] vs 39 days [range 2–169]; P <0.001), whereas SAA concentrations were not associated with survival time. Lower haematocrit at presentation was associated with a reduced median survival time (P = 0.007). Conclusions and relevance In the population examined, no correlation between serum concentration of SAA and prognosis in patients with lymphoma was identified, while low haematocrit and lack of response to treatment were both found to be associated with survival time. SAA concentrations were elevated in patients with non-nasal lymphoma vs patients with tumours confined to the nasal cavity.

A 9-year-old female neutered Miniature Schnauzer was diagnosed with a lingual malignant melanoma on the basis of incisional biopsy and histopathology. The patient was initially given a guarded prognosis of a few months’ survival as surgical treatment options were declined by the owner. In order to control the disease a combination treatment of immunotherapy and tyrosine kinase inhibitors was initiated. The mass showed a marked and sustained reduction in size, whilst preserving quality of life for the patient, with a survival at the time of writing of 15 months since diagnosis. This experience suggests that combination therapy for oral malignant melanoma using immunotherapy and tyrosine kinase inhibitors may be successful in some patients and warrants further investigation.

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Funding informationLinnaeus Veterinary Limited supported the costs of the open access publication charges.

Canine cutaneous mast cell tumours (cMCTs) of the pinna have been associated with an aggressive biological behaviour, although data remain scarce. The knowledge acquired over the past years on histologic gradings, and the value of lymph node (LN) staging, may help in better characterizing this anatomical presentation. The first aim was to describe the frequency, location, and histologic appearance of LN metastases in cMCT of the pinna. A second aim was to evaluate prognosis. Medical records of dogs with cMCT of the pinna, that underwent tumour and sentinel (SLN) or regional LN (RLN) excision, were reviewed. The influence of potential prognostic variables on time to progression (TTP) and tumour‐specific survival (TSS) was investigated. Thirty‐nine dogs were included: 19 (48.7%) had Kiupel high‐grade (K‐HG) and 20 (51.3%) had low‐grade (K‐LG) MCTs. Eighteen (46.1%) dogs underwent SLN mapping: the superficial cervical LN was at least one of SLN in 17 (94.4%) cases. Twenty‐two (56.4%) dogs had LN metastases; the superficial cervical LN was always involved. On multivariable analysis, only K‐HG was associated with increased risk of progression (p = .043) and tumour‐related death (p = .021). Median TTP and TSS were 270 and 370 days in K‐HG, respectively; these were not reached in dogs with K‐LG tumours (p < .01). cMCTs of the pinna are often K‐HG and are also associated with a higher frequency of LN metastasis; however, we confirmed the independent prognostic value of histologic grading. A multimodal treatment may lead to favourable long‐term outcome. Moreover, the superficial cervical LN is most often the SLN.

Canine transmissible venereal tumour (CTVT) is a contagious cancer spread by transfer of living cancer cells. Occasional cases are observed in the UK in dogs imported from endemic regions. Here, we report a case of imported canine transmissible venereal tumour that was transmitted to a second dog within the UK. Transmission of genital canine transmissible venereal tumour occurred despite neutered status of the second dog. The aggressive course of disease in both cases, which included metastasis, resistance to therapeutic interventions and ultimate euthanasia of both dogs, is described. The diagnosis of canine transmissible venereal tumour was made using a combination of cytology, histology, immunohistochemistry and PCR to detect the LINE‐MYC rearrangement. Practitioners unfamiliar with canine transmissible venereal tumour are reminded of this disease of concern, particularly when imported dogs are placed in multi‐dog households, irrespective of neuter status.

Case summary A 7-year-old neutered female domestic longhair cat was presented for further investigation of suspected hepatobiliary disease. Increases in serum 1,2-o-dilauryl-rac-glycero-3-glutaric acid-(6'-methylresorufin) ester lipase and hepatobiliary enzymes, with concurrent hypoalbuminaemia, were documented on blood biochemistry. Abdominal ultrasonography findings were consistent with acute pancreatitis with multiple pancreatoliths visualised within the pancreatic duct. Treatment for suspected triaditis was initiated with a hydrolysed protein diet, amoxicillin–clavulanate, hepatoprotectants and buprenorphine. Fifty-three days later, the patient presented with hypercalcaemia and obstructive pancreatolithiasis, and was euthanased. Post-mortem examination revealed severe chronic active pancreatitis with moderate chronic lymphocytic, plasmacytic cholangiohepatitis and mild chronic lymphocytic–plasmacytic duodenal enteritis (triaditis). Multiple calcium carbonate pancreatoliths present within the pancreatic ducts had resulted in pancreatic duct obstruction. Relevance and novel information Pancreatolithiasis is a very rare condition in cats, with only five reports to date. In human medicine, pancreatolithiasis is often a sequala to chronic pancreatitis, seen in up to 50–90% of patients. However, in cats the aetiology of pancreatolithiasis, and indeed chronic pancreatitis, is poorly understood. This report describes a case of obstructive pancreatolithiasis in a cat with histopathological confirmation of triaditis and is the first report of hypercalcaemia in a cat with obstructive pancreatolithiasis. This further adds to the evidence base that pancreatolithiasis may have a similar pathogenesis to humans and can develop secondarily to chronic pancreatitis in cats.