Complications and influence of cutaneous closure technique on subdermal plexus flaps in 97 dogs (2006-2022).

OBJECTIVE: To determine the incidence and severity of complications for subdermal plexus flaps in dogs and compare the complications when using sutures or staples for cutaneous closure of subdermal plexus flaps. STUDY DESIGN: Retrospective monocentric study. SAMPLE POPULATION: Ninety-seven client-owned dogs. METHODS: Dogs that underwent wound reconstruction using subdermal plexus flaps were retrospectively identified. Type of flap, cutaneous closure technique, complications and level of complication associated with their use were recorded. Follow-up was considered adequate if it was more than 10 days postoperatively or until a complication occurred. RESULTS: Complications were seen in 52 dogs (53.6%), of which 13/18 (72.2%) of dogs had cutaneous closure with skin staples versus 39/79 (49.3%) with skin sutures. The location of the mass/wound on the head and use of an advancement flap was associated with lower incidence of complications (p < .001; p = .018 respectively). Location of the mass/wound on the proximal pelvic limb was associated with a low level of complications (p = .01) on univariable analysis only. On multivariable analysis, only an increased bodyweight was associated with an increased incidence of complications (p = .029). CONCLUSIONS: Increased weight may be associated with an increased risk of complications with subdermal plexus flaps. No risk factor was found to be associated with the severity of complications. CLINICAL SIGNIFICANCE: Overall incidence of complications for subdermal plexus flaps in dogs in this study was 53.6%. The number of dogs included in the study was not sufficient to assess if the skin closure technique affects the incidence of complications.

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.

Marginal excision of cutaneous mast cell tumors in dogs was not associated with a higher rate of complications or prolonged wound healing than marginal excision of soft tissue sarcomas.

OBJECTIVE: To compare wound healing following planned marginal excision of cutaneous mast cell tumors (MCTs) with that of soft tissue sarcomas (STSs) and to identify risk factors for wound healing complications and delay in healing. ANIMALS: 126 dogs that underwent intentional marginal excision of cutaneous MCTs (n = 77) or subcutaneous STSs (49). PROCEDURES: Medical records of included dogs were reviewed and signalment, tumor size, tumor location, skin closure type, time to healing, reported complications, histopathological grade, and surgical margins were recorded. These variables and outcomes (complication rate and time to complete healing) were compared between dogs in the MCT and STS groups. Potential risk factors for complications and delayed healing were analyzed. RESULTS: No significant difference between the groups was found in any of the variables. Wound healing complication rates were 29% (22/77) for the MCT group and 31% (15/49) for the STS group. The mean ± SD time to complete healing was 16.5 ± 7.5 days for the MCT group and 17.7 ± 9.3 days for the STS group. These outcomes did not differ significantly between groups. For both groups, the use of subdermal plexus flap reconstruction was associated with the development of complications and increased time to complete healing. CLINICAL RELEVANCE: Marginal excision of cutaneous MCTs was not associated with a higher rate of complication or prolonged wound healing, compared with marginal excision of STSs. The use of flap reconstruction in skin closure may delay healing and planned adjuvant therapy. Owners should be counseled regarding these risks and where appropriate and feasible, surgery without reconstruction should be considered.

Regulation of COX-2 expression in canine prostate carcinoma: increased COX-2 expression is not related to inflammation.

BACKGROUND: Cyclooxygenase-2 (COX-2) expression has been documented in human and canine prostate carcinoma (PCA). Canine PCA is a histologically heterogeneous tumor, sometimes including inflammatory infiltrates. However, it is unknown whether COX-2 expression in canine PCA is related to the histologic type of tumor, to the presence of inflammation, or to both. Moreover, little is known about the mechanisms regulating COX-2 expression in neoplastic tissue. HYPOTHESIS: COX-2 expression is related to the presence of inflammation in canine PCA and correlates with the degree of tumor differentiation. METHODS: The expression of COX-2 was examined in 28 cases of canine PCA by immunohistochemistry. In addition, a neoplastic and a nonneoplastic canine prostatic cell line were used to investigate the effects of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), phorbol 12-myristate 13-acetate (PMA), epithelial growth factor (EGF), and specific signal transduction pathway inhibitors on COX-2 expression. RESULTS: Twenty-four of the 28 prostate tumors showed COX-2 expression. The presence of inflammatory infiltrates in tumor tissue was associated with lower COX-2 expression scores. In vitro, TNF-alpha, IL-6, and EGF increased COX-2 expression in nonneoplastic cells but not in PCA cells, where baseline expression was high. COX-2 expression in PCA cells could be suppressed by means of specific phosphatidyl inositol-3 kinase (PI3K), protein kinase C (PKC), or inhibitor of extracellular signal-related kinase (ERK/MAPK) inhibitors. CONCLUSIONS AND CLINICAL IMPORTANCE: COX-2 is expressed in canine PCA; however, expression is not related to the presence of inflammatory infiltrates. This conclusion is further supported by the finding that the cytokines TNF-alpha and IL-6 and their involved signaling pathways do not stimulate COX-2 expression in malignant canine prostate cells.

Successful treatment of tracheal lymphoma in a Siamese cat.

CASE SUMMARY: An 8-year-old female spayed Siamese indoor cat presented with a 3 week history of inspiratory dyspnoea, stridor and open-mouth breathing after exercise. Laryngoscopy, tracheoscopy, bronchoscopy and retroflexed nasopharyngoscopy were performed, and identified a multilobulated intraluminal mass within the trachea. Brush cytology was performed on the mass but was inconclusive in providing a definitive diagnosis. A CT scan of the neck failed to identify an obvious intraluminal mass and was negative to contrast uptake. Surgery was performed and seven rings of the trachea were removed to enable the complete excision of the mass. Histopathology of the excised mass was consistent with B cell lymphoma. After surgery, chemotherapy treatment was started. At the time of writing, 20 months since diagnosis, the cat remained clinically well, with no clinical signs or recurrence of macroscopic disease on endoscopic evaluation. RELEVANCE AND NOVEL INFORMATION: Upper airway endoscopy was considered to be an essential diagnostic tool in this case presenting with signs of upper respiratory dyspnoea. Moreover, combined surgery and chemotherapy were considered effective treatments and positively affected the long-term prognosis of this patient.

CAG-repeats in the androgen receptor gene relate with plasma androgen levels in the Bouvier Des Flandres.

BACKGROUND: The Bouvier des Flandres (BdF) dog is predisposed to develop prostate carcinoma (PCA). In humans, ethnic groups with higher prevalence of PCA have higher serum androgens concentrations and shorter polyglutamine (CAG) repeat lengths in the androgen receptor (AR) gene. In dogs, shorter CAG-I lengths are associated with increased PCA risk. OBJECTIVE: To compare serum androgens concentrations in the BdF with other breeds and to determine whether CAG repeats length and plasma androgens concentrations are correlated. MATERIALS AND METHODS: Androgens were measured in 46 BdF and in 53 other dog breed. Length of CAG-I and CAG-III repeats were measured in 41 BdF and correlated with androgen levels. RESULTS: In the BdF group shorter CAG-I and longer CAG-III repeat lengths were associated with lower androgen concentrations. CONCLUSION: As the shorter CAG-I repeat is associated with an increased PCA risk, higher androgen concentrations may protect against the development and progression of PCA.

Transitional cell carcinoma involving the ductus deferens in a dog.

CASE DESCRIPTION: A 12-year-old neutered male Springer Spaniel was referred with a 1-year history of recurring urinary tract infections. Repeated treatment with appropriate antimicrobials selected on the basis of bacterial culture and antimicrobial susceptibility results would result in clinical improvement, but recurrence of clinical signs was observed within days after discontinuation of treatment. CLINICAL FINDINGS: Ultrasound examination revealed a tubular, fluid-filled structure dorsal to the bladder that extended from the midlevel of the bladder to the cranial pole of the prostate. Mineralized foci within a heterogeneous prostatic parenchyma were also noted. Dilation of the right ductus deferens (DD) was observed during exploratory laparotomy. TREATMENT AND OUTCOME: Both DD were surgically removed, and the prostate was biopsied. The histopathological diagnosis was transitional cell carcinoma involving the right DD and the prostate. The dog was treated with meloxicam (0.1 mg/kg [0.05 mg/lb], p.o., q 24 h) for 9 months after diagnosis before being euthanized. CLINICAL RELEVANCE: Because the normal DD is rarely visualized during abdominal ultrasonography in dogs, identification of a tubular, fluid-filled structure dorsal to the bladder may indicate an abnormal DD. Transitional cell carcinoma of the DD should be included in the differential diagnoses of affected patients examined for clinical signs involving the urinary tract.

Zygomatic salivary mucocoele as a postoperative complication following caudal hemimaxillectomy in a dog.

Zygomatic mucocoele is reported as a postoperative complication occurring secondary to a caudal hemimaxillectomy in a two-year-old Labrador retriever. The dog was presented with a history of a rapidly growing oral mass, identified as a soft tissue sarcoma. A caudal hemimaxillectomy via an intraoral approach was performed as treatment for local control of the oral mass. Fifteen days postoperatively, periorbital swelling and exophthalmos developed on the ipsilateral side. The degree of swelling progressed and was identified by computed tomography, ultrasound and cytology as a salivary mucocoele. Zygomatic sialoadenectomy was performed via a modified lateral approach with zygomatic osteotomy. A small amount of discharge persisted from the surgical site but gradually resolved. Recurrence of the periorbital swelling and exophthalmos was noted 25 days later and further surgery was performed to excise residual salivary tissue. Adjuvant radiotherapy was performed, however local recurrence of the oral mass was identified 5 months postoperatively and the patient subsequently euthanased. Salivary mucocoele has been cited as a possible postoperative complication following maxillectomy and mandibulectomy procedures; however to the authors' knowledge, only one previous case report exists in the literature. The current case documents a zygomatic salivary mucocoele occurring subsequent to caudal hemimaxillectomy.

Partial prostatectomy using Nd:YAG laser for management of canine prostate carcinoma.

OBJECTIVE: To report a technique for partial prostatectomy by laser dissection and to evaluate outcome and complications in dogs with prostate carcinoma (PCA). STUDY DESIGN: Experimental and clinical case series. ANIMALS: Four normal dogs and 8 dogs with PCA. METHODS: Subcapsular partial prostatectomy, sparing the urethra and the dorsal aspect of the prostatic capsule, using Nd:YAG laser dissection to remove the prostatic parenchyma and control hemorrhage was performed in 4 normal dogs and subsequently in 8 dogs with histologically confirmed PCA. Additional treatment of PCA dogs included local application of interleukin-2 and systemic administration of meloxicam. Prostate size, complications, and survival time were recorded. Laser-associated thermal damage to surrounding tissue was evaluated by histology. RESULTS: In normal dogs, no damage to the dorsal prostatic capsule or urethra was detected. In PCA dogs, median survival was 103 days (range, 5-239 days). Three dogs died from complications within 16 days, whereas 5 (median survival, 183 days; range, 91-239 days) had improvement or resolution of clinical signs. Urinary incontinence did not occur. CONCLUSION: Laser assisted subcapsular partial prostatectomy can be performed in dogs with PCA without development of postoperative incontinence. CLINICAL RELEVANCE: Subcapsular partial prostatectomy is a potential palliative treatment for PCA in dogs and may lead to the resolution of clinical signs for several months.