Feline primary nonhematopoietic malignant liver tumours: A multicenter retrospective study (2000-2021).

There is scant literature on primary nonhematopoietic malignant liver tumours (PMLT) in cats. In this retrospective study, medical data of 40 cats diagnosed with PMLT were reviewed over a period of 22 years (2000-2021). The most frequent epithelial tumours were hepatocellular (42.5%) and bile duct carcinomas (32.5%), only six (15%) cats had mesenchymal tumours. The median age was 13 years and clinical signs commonly included ano-/hyporexia (62.5%), apathy/lethargy (52.5%), weight loss (42.5%) and vomiting (35%). At initial diagnosis, metastases were confirmed in 1 (2.5%) and suspected in three (7.5%) cats. Massive was the most frequent morphology (75%). Most intrahepatic tumours were left-sided (54.2%) with the left medial lobe being primarily affected (25%). Extrahepatic tumours were rare (5%). In 34 (85%) cats, liver lobectomy was performed (surgery group), four (10%) were treated palliatively (non-surgery group), and two (5%) received no treatment. Intraoperative complications occurred in 11.8% with four (15.4%) postoperative deaths. Recurrence was detected in 28.6% at a median of 151 days (range, 79-684 days), while postoperative metastases were suspected in 21.4% at a median of 186 days (range, 79-479 days). The median survival time (MST) was significantly longer in cats of the surgery group (375 days) than in the non-surgery group (16 days) (p = .002). MST was 868 days for hepatocellular compared to 270 days for bile duct carcinomas (p = .06). In summary, liver lobectomy is associated with prolonged survival times and good prognosis in cats with hepatocellular, and an acceptable prognosis in cats with bile duct carcinoma.

Subcutaneous vascular access port implantation in the axillary or femoral/external iliac vein at the time of full limb amputation in dogs.

OBJECTIVE: To report outcomes and complications after placement of a subcutaneous vascular access port (SVAP) in the jugular (jSVAP), axillary (aSVAP), and femoral or external iliac vein (fSVAP) in dogs. STUDY DESIGN: Retrospective. METHODS: Medical records from a single hospital, covering a period between September 2015 and October 2020, were reviewed to identify dogs that had an SVAP placed. Complications and outcomes for dogs who had an SVAP placed in the axillary vein, or femoral/external iliac vein during amputation for appendicular skeletal neoplasm, and in the external jugular vein were recorded and analyzed statistically. RESULTS: Subcutaneous vascular access ports were placed in the axillary vein in 13 dogs, femoral/external veins in 4 dogs, and in the jugular vein in 19 dogs. The SVAPs fulfilled their purpose throughout treatment in 12/13 aSVAP, 4/4 fSVAP, and 15/19 jSVAP. Dogs were followed for a median of 145.5 days (range 30-945 days). Minor and major complications were recorded in 1/13 and 2/13 aSVAPs, 0/4 and 0/4 fSVAPs, and 3/19 and 4/19 of jSVAPs. Two dogs with jSVAPs were euthanized due to SVAP-related complications. No difference in complication rate was detected between groups (P = .12). CONCLUSION: No difference in short-term outcome was detected between implantation sites for subcutaneous vascular access ports. CLINICAL SIGNIFICANCE: The axillary or femoral/external iliac veins offer alternative sites for placement of SVAP in dogs undergoing limb amputation.

Surgical treatment of a circumferential oesophagogastric mass associated with a peritoneopericardial diaphragmatic hernia in a Maine Coon cat.

Case summary: A 7-month-old intact female Maine Coon presented with a 2-week history of vomiting. A peritoneopericardial diaphragmatic hernia (PPDH) and a mass arising from the cardia, protruding into the gastric lumen, were diagnosed using a combination of ultrasound and CT. An exploratory gastrotomy revealed a circumferential, irregular, ulcerated mass involving the submucosal layer of the cardia. This mass was excised by partial-thickness resection of the gastro-oesophageal wall. The PPDH was corrected and a gastrostomy feeding tube was placed under the same anaesthetic. Histopathologically, the most characteristic feature of this mass was a submucosal fibroplasia associated with marked ulceration and granulation tissue. No infectious or neoplastic cells were identified. The affected region of the gastric wall appeared narrowly excised. Resolution of clinical signs was achieved until the cat was lost to follow-up 12 months postoperatively. Relevance and novel information: This is the first report of the surgical management of an oesophagogastric mass in a cat with a concurrent PPDH and no other underlying disease. A benign fibrous mass should be considered as a differential diagnosis of an oesophagogastric mass in feline patients with PPDH. While medical and surgical options are debated for the management of PPDH, symptomatic patients with a concurrent oesophagogastric mass are legitimate candidates for surgical herniorrhaphy to prevent further complications. Based on this case, prognosis can be considered good if surgical resection is complete.

Partial laryngectomy for the management of laryngeal masses in six cats.

OBJECTIVES: Partial laryngectomy is an organ-sparing surgical procedure for the removal of laryngeal masses which has not been described in cats. The aim of this study was to report on the surgical procedure and the short- and long-term clinical outcomes of cats that underwent partial laryngectomy. METHODS: Medical records were retrospectively collected over a 4-year period in two institutions. The following data were retrieved: signalment, history, clinical signs, diagnostic test results, surgical procedure, postoperative management, complications and outcome. RESULTS: Six cats underwent partial laryngectomy. The most common clinical signs in cats with laryngeal masses were stridor (n = 4) and dyspnoea (n = 4). In all cats, a full-thickness portion of one or several laryngeal cartilages was resected, including thyroid cartilage alone (n = 2), thyroid cartilage and arytenoid (n = 2), and arytenoid cartilage and epiglottis (n = 2). The resected laryngeal masses were reported to be lymphoma (n = 3), carcinoma (n = 1), laryngeal cyst (n = 1) and inflammatory laryngeal disease (n = 1). All cats survived the surgical intervention of partial laryngectomy. Four cats showed varying degrees of respiratory distress in the short-term postoperative period. A temporary tracheostomy tube was placed in two cats. No other postoperative complications were noted in the short- or long-term. Four cats were still alive at the time of writing. These cats survived at least 252 days. CONCLUSIONS AND RELEVANCE: In a small number of cases, our results show that successful long-term outcomes after partial laryngectomy are achievable, with longer survival times than previously reported. Therefore, partial laryngectomy should be considered as a viable treatment option in cats with laryngeal masses.

Comparison of Fat Harvested from Flank and Falciform Regions for Stem Cell Therapy in Dogs.

BACKGROUND: Adipose tissue has recently gained attention as a source of mesenchymal stem cells (AdMSCs) for applications in treating degenerative joint disease in veterinary patients. This study aimed to quantify the stromal vascular fractions (SVFs) and colony forming units (CFU) of AdMSCs from the falciform and flank regions and compare dogs of different ages and weights. METHODS: Fat tissue was harvested from the flank (21 dogs) and falciform regions (17 dogs). The fat tissue was enzymatically digested and the number of nucleated cells in the SVF was counted. The SVF was cultured in vitro and the cell growth was assessed by counting the CFU per gram of fat and the aspect ratio of the cells. CONCLUSIONS: There was no significant difference in the number of nucleated cells in the SVF from the two sites. The CFU/g of fat from falciform was 378.9 ± 293 g and from flank was 486.8 ± 517 g, and this was also insignificant. Neither age nor weight of the patient had an impact on the SVF or CFU/g. No surgical complications were reported from either of the sites. Harvesting fat for stem cell therapy for intra-articular therapy of degenerative joint disease can be an easy and fast process when obtaining the fat either from the flank or the falciform region, and it is not age or weight dependent. The harvest site for clinical canine patients can be left to the surgeon's discretion and comfort.

Spontaneous Regression of a Mandibular Plasmacytoma in a Juvenile Dog: A Case Report.

A 4 mo old female Finnish lapphund presented for further investigation of a swelling of the right rostral mandible. A computed tomography scan showed the swelling to be an expansile and osteolytic mandibular lesion. Histopathology revealed a poorly differentiated, moderately well-demarcated, unencapsulated, highly infiltrative round cell neoplasm, and immunohistochemistry was supportive of a plasmacytoma. Performance of a rostral partial mandibulectomy was initially discussed with the owners, but the lesion improved spontaneously both clinically and on repeated computed tomography scanning before surgery could be performed. It subsequently almost completely resolved 6 mo after diagnosis. Hypotheses for spontaneous regression of the lesion are discussed and the human literature is briefly reviewed.

Quantification of tissue shrinkage in canine small intestinal specimens after resection and fixation.

The aim of this study was to quantify the longitudinal shrinkage of canine small intestinal specimens after resection and fixation in 10% formalin. Samples were obtained from 12 clinically normal dogs of medium to large breed via ventral midline coeliotomy and enterectomy. The length of each sample was measured before excision, immediately after excision, and after 24 h in 10% formalin. The results were interpreted with the use of single-sample t-tests of the average changes; P-values of less than 0.01 were considered significant. The samples indicated a significant decrease in length after resection and fixation. The mean shrinkage from the pre-excision state was 28.3% immediately after excision (P < 0.0001) and 26.3% after 24 h of fixation (P < 0.0001). There was a small but not significant increase in the length of the specimens between the 2nd and 3rd measurement points. Quantification of the longitudinal shrinkage of resected intestinal specimens may improve interpretation of the distance of surgical margins from abnormal tissue in histopathology reports and allow investigation of the margins required for the clearance of specific tumors.

L'objectif de la présente étude était de quantifier le rétrécissement longitudinal de spécimens de petit intestin de chiens après résection et fixation dans de la formaline 10 %. Des échantillons ont été obtenus de 12 chiens cliniquement normaux de race moyenne à large via entérectomie et céliotomie via la ligne blanche ventrale. La longueur de chaque échantillon a été mesurée avant excision, immédiatement après l'excision, et après 24 h dans 10 % de formaline. Les résultats des changements moyens ont été interprétés au moyen de test de t pour échantillon unique; les valeurs de P inférieures à 0,01 étaient considérées significatives. Les échantillons ont montré une diminution significative de leur longueur après la résection et la fixation. Le rétrécissement moyen par rapport à l'état pré-excision était de 28,3 % immédiatement après l'excision (P < 0,0001) et 26,3 % après 24 h de fixation (P < 0,0001). Il y avait une légère, mais non significative, augmentation de la longueur des spécimens entre la 2e et la 3e mesure. La quantification du rétrécissement longitudinal des spécimens d'intestin réséqués pourrait améliorer l'interprétation de la distance des marges chirurgicales de tissus anormaux dans les rapports d'histopathologie et permettre l'étude des marges requises pour l'enlèvement de tumeurs spécifiques.(Traduit par Docteur Serge Messier).

Total scapulectomy for the treatment of chondrosarcoma in a cat.

CASE DESCRIPTION: A 10-year-old neutered male domestic shorthair cat was admitted for treatment of a mass affecting the right scapula. CLINICAL FINDINGS: A firm soft tissue mass located over the craniolateral aspect of the right scapula was evident during palpation. The mass extended close to the shoulder joint but did not cause lameness of the affected limb. TREATMENT AND OUTCOME: Examination of a biopsy specimen obtained from the mass indicated chondrosarcoma. Total scapulectomy was performed to allow wide excision of the tumor. Weight bearing on the operated limb was tolerated 12 hours after surgery. Six months after surgery, limb function was assessed and considered excellent. The owner reported that the cat had its typical amount of activity and was able to jump and play normally. No recurrence of the tumor was evident 6 months after surgery. CLINICAL RELEVANCE: On the basis of the functional outcome after surgery, total scapulectomy may be a viable limb-sparing technique for the treatment of local neoplasms in cats. Subtotal scapulectomy has been reported previously, with a good to excellent clinical outcome expected. Total scapulectomy associated with only a fair clinical outcome has been reported previously, which has led to the general recommendation that scapulectomy be performed with preservation of the shoulder joint. The information provided in this report revealed that total scapulectomy can be associated with an excellent outcome in a cat.

Inhibition of catecholamine-induced cardiac fibrosis by an aldosterone antagonist.

In heart failure, the renin-angiotensin-aldosterone and the sympathetic systems are overactivated and lead to formation of cardiac fibrosis, which contributes to the aggravation of cardiac function. The aim of the present study was to evaluate the role of aldosterone and angiotensin II on formation of left ventricular fibrosis induced by chronic beta-adrenergic stimulation with isoproterenol (iso) in the rat heart failure model induced by myocardial infarction (MI). Rats were submitted to chronic treatment with either the aldosterone receptor antagonist potassium canrenoate (pc, 20 mg/kg/d) or both aldosterone and angiotensin II receptor antagonists with addition of losartan (los, 10 mg/kg/d). Isoproterenol induced cardiac hypertrophy, which was completely inhibited by potassium canrenoate alone in atria and by potassium canrenoate plus losartan in infarcted ventricles. Isoproterenol also induced cardiac fibrosis, which was completely inhibited in infarcted rats by potassium canrenoate alone in right and left ventricles. In left ventricle, extent of fibrosis was, for control MI, 1.30 +/- 0.34%; MI + iso, 2.50 +/- 0.27%; MI + iso + pc, 0.82 +/- 0.11%; and MI + iso + pc + los, 1.47 +/- 0.31%. The deleterious effects of beta-adrenoceptor stimulation on cardiac fibrosis seem therefore to involve aldosterone action. These results suggest a transregulation between the adrenergic and mineralocorticoid pathways, most likely at the nucleus level, with activation of profibrotic genes.

Toxic cardiac effects of catecholamines: role of beta-adrenoceptor downregulation.

The aim of our study was to analyse the mechanisms underlying cardiac toxicity caused by beta-adrenoceptor stimulation and the relationships with their associated downregulation during heart failure. We used the experimental model of coronary artery ligation-induced myocardial infarction in male Wistar rats. In order to increase beta-adrenergic stimulation, rats were subjected to a 15-day chronic isoprenaline administration (30 microg/kg/h). Isoprenaline administration induced haemodynamic inotropic compensation, almost abolished in vitro inotropic response to isoprenaline on papillary muscle (P<0.005) but promoted fibrosis. Isoprenaline treatment markedly reduced the B(max) of beta(2)-adrenoceptors (by 53% in sham and 44% in infarcted rats) but not that of beta(1)-adrenoceptors. These results suggest that beta(1)-adrenoceptors rather than beta(2)-adrenoceptors underlie the deleterious effects of chronic beta-adrenergic stimulation on cardiac fibrosis and are in agreement with the demonstrated benefit induced in human heart failure by beta(1)-adrenoceptor antagonists.