Search

Acquired pulmonary artery branch stenosis without main pulmonary artery involvement due to external compression by neoplasia has been described in human and veterinary medicine. Over time, this can result in right ventricular hypertension and right-sided heart failure. Endovascular stenting offers quick relief from signs, while the underlying cause is addressed. Here, we present a dog with severe right pulmonary artery compression caused by a chemodectoma, which was treated with two, overlapping, self-expanding vascular stents and chemotherapy. The patient experienced immediate symptomatic relief, progressive stent expansion over time, and has been free of clinical symptoms for 5 months post implantation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ferrel, Winter, Maneval, Matz, Bergman, Starbird, Koehler and Liao.)

Objective:  The aim of this study was to compare the bending properties of String of Pearls plate-bone substitute constructs with and without bending tees in the nodes over a simulated fracture gap. It is hypothesized that the constructs with tees will have higher bending stiffness., Study Design:  Acetal polymer tubes and 12-hole, 3.5-mm String of Pearls plates were used to create plate-bone substitute constructs simulating stabilization in a bridging fashion over a 45-mm gap. Twenty-four constructs were made with 12 containing tees in the nodes over the fracture gap. Single-cycle load-to-failure 4-point bending was performed in mediolateral and craniocaudal planes. Bending stiffness was compared with a t -test ( p  < 0.05)., Results:  All plate-bone substitute constructs had a permanent loss of structural integrity via plastic deformation of the plate. The bending stiffness (mean ± standard deviation) of the craniocaudal group was 59.11 ± 1.98 N/mm with tees and 59.25 ± 1.69 N/mm without tees ( p  = 0.88). In the mediolateral group, the bending stiffness was 43.17 ± 0.75 N/mm with tees and 41.09 ± 0.91 N/mm without tees ( p  = 0.0042)., Conclusion:  In 4-point bending, the plate-bone substitute constructs with tees had equivalent bending stiffness in the craniocaudal plane and increased bending stiffness in the mediolateral plane. However, with a small absolute difference in values, the clinical significance is unclear. Future studies for cyclic bending, torsional, and axial compression tests should be performed to further investigate the value of tees in the nodes over a comminuted or gap fracture repaired in a bridging fashion., Competing Interests: None declared., (Thieme. All rights reserved.)

Objective: To describe cytologic findings from mandibular and superficial cervical lymph nodes in dogs with thyroid carcinoma and to determine prognostic factors associated with lymph node metastasis., Animals: A total of 71 client-owned dogs with confirmed thyroid carcinoma that had cytologic results from at least 1 mandibular or superficial cervical lymph node between 2010 and 2020., Procedure: Medical records from 2 referral veterinary hospitals were retrospectively reviewed. Cytology of lymph nodes was reviewed for presence of metastasis by diplomates of the American College of Veterinary Pathologists. Thyroid tumor diameter and volume, tumor fixation, bilateral location, vascular invasion, and stage were recorded to determine effects on nodal metastasis., Results: A total of 154 lymph nodes (104 mandibular and 50 superficial cervical lymph nodes) from 71 dogs were cytologically evaluated, and 1/154 (0.6%) and 2/154 (1.3%) lymph nodes were noted to be definitively metastatic or probably metastatic, respectively. Given the infrequent rate of nodal metastasis (1.9% or less), statistical analysis of potential prognostic variables was not completed., Conclusion and Clinical Relevance: Routine lymph node cytology of mandibular and superficial cervical lymph nodes appeared to be of low yield when assessing for metastasis of canine thyroid carcinomas. The medial retropharyngeal and deep cervical lymph nodes should continue to be evaluated as they appeared to have higher metastatic rates, based on historic reports. Additional studies are needed to determine prognostic factors associated with lymph node metastasis and effects on patient survival., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Osteosarcoma (OSA) is a highly aggressive bone tumor primarily affecting pediatric or adolescent humans and large-breed dogs. Canine OSA shares striking similarities with its human counterpart, making it an invaluable translational model for uncovering the disease's complexities and developing novel therapeutic strategies. Tumor heterogeneity, a hallmark of OSA, poses significant challenges to effective treatment due to the evolution of diverse cell populations that influence tumor growth, metastasis, and resistance to therapies. In this study, we apply single-nuclei multiome sequencing, encompassing ATAC (Assay for Transposase-Accessible Chromatin) and GEX (Gene Expression, or RNA) sequencing, to a treatment-naïve primary canine osteosarcoma. This comprehensive approach reveals the complexity of the tumor microenvironment by simultaneously capturing the transcriptomic and epigenomic profiles within the same nucleus. Furthermore, these results are analyzed in conjunction with bulk RNA sequencing and differential analysis of the same tumor and patient-matched normal bone. By delving into the intricacies of OSA at this unprecedented level of detail, we aim to unravel the underlying mechanisms driving intra-tumoral heterogeneity, opening new avenues for therapeutic interventions in both human and canine patients. This study pioneers an approach that is broadly applicable, while demonstrating significant heterogeneity in the context of a single individual's tumor.

Objective: To report the outcomes and complications associated with staphylectomy in nonbrachycephalic dogs., Animal: Twenty-seven nonbrachycephalic dogs with elongated soft palates and undergoing staphylectomy., Procedure: Retrospective study., Results: Increased upper airway noise (70.4%) and dyspnea (44.4%) were the most common presenting clinical signs. Concurrent upper airway abnormalities found in the study population included laryngeal collapse (25.9%) and laryngeal paralysis (14.8%). The most common staphylectomy technique used in this study was sharp excision (66.7%) with sutured oral and nasal mucosal apposition. The dogs in this study had an overall minor postoperative complication rate of 33.3%, with regurgitation/vomiting (11.1%) and coughing (11.1%) occurring most commonly. No dog required supplemental oxygen therapy or temporary tracheostomy., Conclusion: Staphylectomy was well-tolerated in nonbrachycephalic dogs and was associated with a relatively low rate of complications. Concurrent airway abnormalities were common among nonbrachycephalic dogs with elongated soft palates, similar to brachycephalic dogs., Clinical Relevance: Clinicians should be aware that elongated soft palate can occur in nonbrachycephalic dogs, and surgical correction can be achieved with rare major or catastrophic complications., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Objective: The objective of this study was to describe the clinical features, prognostic factors, and outcomes in dogs with surgically treated salivary gland carcinoma., Study Design: Multi-institutional retrospective case series., Animals: Seventy-two client-owned dogs from 16 institutions with surgically excised salivary gland carcinoma., Methods: Medical records of dogs undergoing sialoadenectomy from January 1, 2000 to January 1, 2020 were reviewed for signalment, clinical signs, preoperative staging results, preoperative mass evaluation, complications, histopathologic diagnosis, local recurrence, metastatic disease, and survival times. Survival functions were estimated using the Kaplan-Meier estimator. Factors related to survival were individually tested using the log-rank test., Results: The overall median survival time (MST) associated with salivary carcinoma was 1886 days. Local recurrence occurred in 29/69 (42%) dogs with an overall disease-free interval (DFI) of 191 days. Metastatic disease occurred in 22/69 (31.9%) dogs, with an overall DFI of 299 days. Lymph node metastasis was present at the time of surgery in 11/38 (28.9%) dogs in which lymphadenectomy was performed at the time of surgery; these dogs had a shorter DFI at 98 days (P = .03) and MST at 248 days (P < .001)., Conclusion: The prognosis for dogs with salivary gland carcinoma treated surgically was more favorable than previously reported. Nodal metastasis was a negative prognostic factor for canine salivary gland carcinoma., Clinical Significance: Surgical intervention should be considered for dogs with salivary carcinoma., (© 2023 American College of Veterinary Surgeons.)

Background: Greater than 90% of dogs with appendicular osteosarcoma will develop pulmonary metastasis despite the standard of care. Available treatments have limited efficacy for stage III disease. Zoledronate, a bisphosphonate, induces apoptosis of canine osteosarcoma cells and appears to modulate the tumour microenvironment., Objectives: This prospective, single institutional phase IIa trial investigated the use of single agent zoledronate in dogs with pulmonary metastases from osteosarcoma., Methods: Zoledronate was administered once monthly, and thoracic radiographs were used to assess response., Results: Eleven dogs were enrolled. Stable disease was achieved in two of eight dogs available for response assessment. The median progression-free survival was 28 days (range: 4-93 days). The median stage III-specific survival time was 92 days. Adverse events were reported in four dogs; two dogs developed grade III or higher toxicities. Notable adverse events included conjunctivitis, fever, hypocalcaemia, and hypophosphatemia., Conclusions: Zoledronate appears to have limited efficacy as a single agent for stage III osteosarcoma and may be associated with unexpected toxicity in this population. This clinical trial was registered on the AVMA Animal Health Studies Database (AAHSD004396)., (© 2022 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.)

Objective: To determine the influence of staple size on leakage pressure of typhlectomy sites in canine cadavers., Study Design: Randomized, experimental cadaveric study., Animals: Twenty-four fresh canine cadavers., Methods: Ileocecocolic segments were exteriorized following right paracostal laparotomy after euthanasia. Cecal base length and wall thickness were measured. Each cecum was randomly assigned to 1 of 3 groups (TA 30 V3 2.5 mm, TA 60 3.5 mm, and TA 60 4.8 mm). The cecal base was stapled and the cecum was removed. A 10 cm segment including the stapled cecal excision site was tested for initial leak pressure., Results: The mean ± standard deviation body weights across the groups were 18.7 ± 6.1 kg, 16.2 ± 7.5 kg, and 14.2 ± 5.5 kg for the TA 30 V3 2.5 mm, TA 60 3.5 mm, and TA 60 4.8 mm groups, respectively (P = .48). There were no differences for mean cecal base length or wall thickness. Mean initial leak pressure (ILP) across groups was 182 ± 111 mmHg (TA 30 V3 2.5 mm), 112 ± 57 mmHg (TA 60 3.5 mm), and 77 ± 60 mmHg (TA 60 4.8 mm) (P = .78)., Conclusion: Each stapler size that was evaluated resulted in a mean ILP in excess of typical intraluminal pressures under normal circumstances. There were no differences among groups., Clinical Significance: The results of this cadaveric study support the use of any of the stapler sizes evaluated in similarly sized dogs. A prospective study is needed to be able to correlate stapler size and clinical outcome., (© 2022 American College of Veterinary Surgeons.)

In collaboration with the American College of Veterinary Pathologists.

The objective of this study was to compare maximal leakage pressures and locations of 2 functional end-to-end stapled anastomosis (FEESA) constructs. Grossly normal jejunum was harvested from 4 large breed dogs. Thirty-two 8-cm segments of bowel were used to construct 16 FEESA. Construct type was divided into 2 groups: traditional FEESA (tFEESA) and modified FEESA (mFEESA). Leakage pressures and locations were recorded and compared for the 2 groups. There was no difference in the leakage pressures of the tFEESA and the mFEESA. However, 1 tFEESA did leak at subphysiologic intestinal peristaltic pressures. Although no difference in maximal leakage pressure was detected between the 2 constructs, mFEESA is an attractive alternative to tFEESA, as it requires less equipment and none of the mFEESA constructs leaked at subphysiologic pressures., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Objective: To determine the outcome in dogs diagnosed with congenital extrahepatic portosystemic shunts (EHPSS) at ≥ 5 years of age treated with medical management only (M) or with surgical attenuation (S). The hypothesis was that dogs undergoing surgical attenuation would have a longer survival time than dogs undergoing medical management only., Animals: 351 dogs definitively diagnosed with EHPSS at ≥ 5 years of age., Procedures: Medical records from 2009 to 2019 at 16 veterinary teaching hospitals were evaluated. Data collected included signalment, clinical signs at diagnosis, clinicopathologic data, surgical and medical treatments, shunt morphology, clinical signs and medical treatments at 6 to 12 months after diagnosis, and survival time., Results: 351 dogs (M, 119 [33.9%]; S, 232 [66.1%]) were included in the study. Survival time was longer with surgery than medical management (hazard ratio, 4.2; M, 3.4 years; S, 10.9 years). Continued clinical signs at 6 to 12 months after diagnosis were more common with medical management (M, 40% [33/88]; S, 14% [21/155]). Continued medical treatments at 6 to 12 months after diagnosis were more common in the medical management group (M, 78% [69/88]; S, 34% [53/155]). Perioperative mortality rate was 7.3%., Clinical Relevance: Dogs diagnosed at ≥ 5 years of age with EHPSS have significantly better survival times and fewer clinical signs with surgical attenuation, compared with medical management. Older dogs have similar surgical mortality rates to dogs of all ages after surgical EHPSS attenuation.

The objective of this report is to describe the surgical technique for total laryngectomy and outcome in six dogs. Laryngeal cancer is an uncommon and challenging clinical problem. Total laryngectomy can provide local disease control but is uncommonly performed. Detailed procedural descriptions are limited and similarly limited information is available regarding patient outcome. Institutional medical records were searched for dogs treated with total laryngectomy. Six dogs were identified. The procedure resulted in postoperative quality of life similar to permanent tracheostomy alone. Surgical margin status was evaluated in five of six cases and was complete in those five. All dogs survived to discharge from the hospital. Complications were mostly related to tracheostomy occlusion or collapse which is recognized as a complication associated with permanent tracheostomy. Patient quality of life was acceptable. Local recurrence was suspected in one dog. Recurrence was not observed in the case with unknown margin status., (© 2021 John Wiley & Sons Ltd.)

Excellent outcomes have been reported following thyroidectomy for thyroid carcinoma in dogs, but outcomes for thyroid carcinomas with gross vascular invasion are poorly described. This study describes the clinical outcomes and complications in dogs with thyroid carcinomas with gross vascular invasion undergoing thyroidectomy. Medical records of dogs that underwent thyroidectomy between January 1st 2010 and December 31st 2019 were reviewed at 10 hospitals. Signalment, diagnostic data, primary and adjuvant treatments performed, and outcome were abstracted. Survival was calculated using Kaplan-Meier analysis. Multiple logistic regression was used to identify variables associated with disease-specific survival. Seventy-three dogs were included, of which 58 underwent unilateral thyroidectomy and 15 underwent bilateral thyroidectomy. Complications were reported in five dogs (three major, two minor; 6.8%) intraoperatively and 12 dogs (two major leading to death, 10 minor; 16.4%) postoperatively. Seven (9.6%) dogs developed locoregional recurrence at a median of 238 days postoperatively (range: 15-730 days). Distant metastasis was suspected or confirmed in nine dogs (12.3%) at a median of 375 days postoperatively (range: 50-890 days). Twenty-seven dogs (37%) received adjuvant therapy (chemotherapy: n = 21; radiotherapy: n = 6). Thirty-nine dogs were euthanized or died, with 20 deaths related to disease (n = 10) or of unknown cause (n = 10), 19 due to unrelated causes, and nine lost to follow-up. Median overall and disease-specific survival were 621 days and not reached respectively. One-year disease-specific survival rate was 82.5%. No variables were associated with disease-specific survival in our dataset. Surgery may be considered for loco-regional therapy in dogs with thyroid carcinoma with gross vascular invasion., (© 2021 John Wiley & Sons Ltd.)

Osteosarcoma is one among the most common neoplasms in dogs. Current treatments show limited efficacy and fail to prevent metastasis. Conditionally replicative adenoviruses (CRAd) replicate exclusively in targeted tumor cells and release new virus particles to infect additional cells. We proposed that OC-CAVE1 (CAV2 with the E1A promoter replaced with the osteocalcin promotor) may also enhance existing immunity against tumors by overcoming immune tolerance via exposure of new epitopes and cytokine signaling. Eleven client-owned dogs with spontaneously occurring osteosarcomas were enrolled in a pilot study. All dogs were injected with OC-CAVE1 following amputation of the affected limb or limb-sparing surgery. Dogs were monitored for viremia and viral shedding. There was minimal virus shedding in urine and feces by the 6th day and no virus was present in blood after 4 weeks. CAV-2 antibody-titers increased in all of the patients, post-CRAd injection. Immunological assays were performed to monitor 1) humoral response against tumors, 2) levels of circulatory CD11c + cells, 3) levels of regulatory T cells, and 4) cytotoxic activity of tumor specific T cells against autologous tumor cells between pre-CRAd administration and 4 weeks post-CRAd administration samples. Administration of the CRAd OC-CAVE1 resulted in alteration of some immune response parameters but did not appear to result in increased survival duration. However, 2 dogs in the study achieved survival times in excess of 1 year. Weak replication of OC-CAVE1 in metastatic cells and delay of chemotherapy following CRAd treatment may contribute to the lack of immune response and improvement in survival time of the clinical patients., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

The goal of this study was to evaluate whether fine-needle aspirate cytology of a previous surgical site was predictive of recurrence for incompletely excised mast cell tumors (MCTs). Electronic medical records were searched for dogs diagnosed with MCTs; those with histologically confirmed, incompletely resected MCTs evaluated by scar aspiration cytology within 60 days after surgery were included for analysis. Variables were compared between groups using Fisher's exact test and logistic regression. Twenty-nine cutaneous and 7 subcutaneous tumors were evaluated. Local recurrence, confirmed by either histopathology or cytology, occurred in 13.8% of cases. No significant differences were identified for any variables other than surgical site cytology status. The negative predictive value of surgical site aspirate cytology without residual mast cell tumor was 93.5%, with an overall predictive accuracy of 88.9%. For the dogs evaluated in this report, surgical site aspiration cytology was predictive of local disease control for incompletely resected MCTs., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Sentinel lymph node (SLN) mapping by various means has become standard of care in certain types of human cancers and is receiving more attention in veterinary oncology. Current SLN mapping techniques can be costly and often require advanced imaging equipment. The objective of this prospective, method comparison study was to compare an SLN mapping protocol of lymphoscintigraphy to lymphography using water soluble iodinated contrast medium (WIC) and digital radiography for identification of an SLN. Lymphoscintigraphy and lymphography were performed on eight healthy purpose-bred dogs using technetium-99m sulfur colloid and WIC injected into the subcutaneous tissues in a four-quadrant technique around a predefined area of skin on the brachium. Images were obtained using a gamma camera and digital radiography at different time points post-injection. Image sequences were evaluated by one of two American College of Veterinary Radiology board-certified veterinary radiologists. Data obtained were compared between methods using descriptive statistics. An SLN was identified in all dogs with lymphoscintigraphy and seven of eight dogs with lymphography. Agreement between results of the lymphoscintigraphy and lymphography studies was a complete match in three dogs, a partial match in four dogs, and no match in one dog. The SLN detected differed based on the imaging modality used., (© 2020 American College of Veterinary Radiology.)

Objective: To determine the effect of surgery on lymphoscintigraphy drainage patterns from the canine brachium., Study Design: Experimental study., Animals: Eight healthy research beagles., Methods: A predefined area of skin measuring 2 × 1.5 cm in dimension was designated on either the right or left brachium. Preoperative lymphoscintigraphy was performed with technetium sulfur colloid injected into the subcutaneous tissues around the predefined anatomic location in a four-quadrant technique. Dogs underwent surgery for excision of the predefined area of skin, subcutis, and fascia of the lateral head of the triceps muscle with 1-cm margins. Eighteen days after surgery, lymphoscintigraphy was again performed with technetium sulfur colloid injected into the subcutaneous tissues around the surgical scar in a four-quadrant technique., Results: Sentinel lymph nodes were identified in eight of eight dogs preoperatively and in eight of eight dogs postoperatively. Agreement between the results of the preoperative and postoperative lymphoscintigraphy studies was identified as complete in four of eight dogs and partial in four of eight dogs. Sentinel lymph node identification occurred immediately in three of eight dogs preoperatively and in eight of eight dogs postoperatively., Conclusion: Sentinel lymph node identification occurred faster postoperatively. Agreement or partial agreement between the results of the preoperative and postoperative lymphoscintigraphy studies was observed in eight of eight dogs., Clinical Significance: Surgery appears to have an effect on lymphoscintigraphy drainage patterns. Additional studies are required to compare preoperative and postoperative sentinel lymph node mapping patterns in tumor-bearing dogs. However, this study provides preliminary information regarding the effect of surgery on sentinel lymph node identification., (© 2020 The American College of Veterinary Surgeons.)

The objective of this retrospective study was to describe the outcome and incidence of splenic malignancy in 18 dogs undergoing partial splenectomy for incidentally detected, non-ruptured splenic lesions. Incidence of splenic malignancy in the present study was 5.6% [95% confidence interval (CI): 0.14% to 27.65%]. Median diameter of splenic nodules was 2 cm (range: 1.5 to 4 cm). Splenic hemangiosarcoma was diagnosed in 1 dog, while the remaining 17 dogs had benign splenic lesions. There was a higher incidence of non-splenic malignancy (50%) than splenic malignancy (5.6%) in the study population. Overall median survival time after surgery was 300 days (range: 4 to 1332 days). Median survival time in dogs with malignant disease (splenic and non-splenic) was 67 days (range: 4 to 425 days) and for non-malignant disease was 727 days (range: 8 to 1332 days). In conclusion, partial splenectomy may be appropriate for small, incidental non-ruptured splenic lesions in dogs., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Background: Early enteral nutrition in dogs with critical illnesses, including septic peritonitis, has been shown to have a positive influence on patient outcome. Surgical placement of a gastrostomy tube (GT) is one option for providing early enteral nutrition. Complications, including premature tube removal or separation of the stomach from the body wall, can result in leakage of gastric contents into the abdominal cavity and subsequent peritonitis. A safe and reliable technique for the placement of a GT is desirable to minimize such complications., Key Concepts: A modified method for surgical placement of a GT is described. A thoracic trocar catheter (TTC) with an attached Pezzer tube is inserted through a gastrotomy incision and exited through the left gastric body and body wall. A left-sided tube gastropexy is performed using an interlocking box (ILB) pattern., Significance: GT placement using a TTC is efficient, requiring minimal additional anesthesia time. The gastric defect created by the TTC conforms well with the Pezzer tube. As such, placement and utilization of the ILB suture pattern enables removal of the GT in the early postoperative period, if appropriate., (© Veterinary Emergency and Critical Care Society 2019.)

Objective: To describe the postoperative use of gastrostomy tubes (GT) in dogs with septic peritonitis. A secondary objective was to identify factors associated with GT placement and use that may be related to outcome., Design: Retrospective study., Setting: University teaching hospital., Animals: Twenty-four dogs diagnosed with septic peritonitis with GT placement at the time of exploratory laparotomy., Interventions: None., Measurements and Main Results: Eighteen dogs (75%) survived to discharge. Eighteen dogs (75%) had a gastrointestinal source of septic peritonitis. Complications were reported in 12/24 (50%) patients. Four dogs (16.6%) had non-GT-related complications such as vomiting, regurgitation, or increased gastric residual volume. GT-related complications occurred in 8/24 (33.3%) dogs, the majority of which (6/8 [75%]) were minor and did not necessitate removal of the GT. Two dogs had major complications that required removal of the GT. Significant differences between survivors and nonsurvivors were found between the length of time after placement of the GT to when they began eating and outcome (discharge versus death versus euthanasia) (P = 0.03), and GT dwell time (length of time the GT was in place) and outcome (P = 0.006). Clinically relevant correlations were found between the time after placement of the GT until feeding and time after placement until voluntarily eating (P = 0.0349), time after placement of the GT until voluntarily eating and length of hospitalization (P = 0.0391), and time after placement of the GT until feeding and length of hospitalization (P = 0.036)., Conclusions: GTs can be placed during exploratory laparotomy in dogs with septic peritonitis. They facilitate early enteral nutrition and are associated with few clinically significant complications. Prospective studies are needed to determine the optimal postoperative feeding plan and the effects of early enteral nutrition on serum albumin concentration in this patient population., (© Veterinary Emergency and Critical Care Society 2019.)

Primary abdominal visceral soft tissue sarcomas (STSs) are rare tumours in dogs with little information available on outcomes. The goal of this retrospective, multi-institutional study was to describe the common tumour types, location and prognostic factors associated with primary abdominal visceral STSs. Medical records were searched for dogs with primary abdominal visceral STSs at six institutions and were retrospectively reviewed. Tumours were graded using the previously described grading scheme for STSs of the skin and subcutis when information in the histopathology report contained adequate details. Forty-two dogs were included in the study. Five dogs had grade I tumours, 11 had grade II and 15 had grade III tumours. The most common tumour type was leiomyosarcoma (38.1%). The most common tumour locations were the spleen (47.6%) and small intestine (23.8%). The local recurrence rate was low (4.7%). Metastasis was present at the time of surgery in 23.8%, and the overall metastatic rate was 40.4%. Mitotic index of ≥9 was associated with significantly shorter survival time (MST 269 days) compared with a mitotic index of <9 (MST not reached). The MST for grade I STSs was not reached, was 589 days for grade II and 158 days for grade III. Dogs with grade III tumours were more likely to develop metastatic disease. Neither location of the primary tumour nor the histologic subtype was associated with survival time. Histologic grading of abdominal visceral STSs using the previously described scheme is prognostic and should be provided on histopathology reports., (© 2019 John Wiley & Sons Ltd.)

Objective: To describe the clinical characteristics, perioperative complications, and outcomes in dogs surgically treated for gastric carcinoma., Study Design: Multi-institutional retrospective case series., Animals: Forty client-owned dogs with histologically confirmed gastric carcinoma., Methods: Medical records were reviewed for preoperative diagnostics, surgery, histopathology, postoperative complications, adjuvant chemotherapy, disease progression, and survival. Variables were assessed for associations with outcome by using Cox proportional hazards regression analysis., Results: Surgical treatment included partial gastrectomy (28 dogs), Billroth I (9 dogs), subtotal gastrectomy (2 dogs), and submucosal resection (1 dog). Major postoperative complications occurred in 8 of 40 dogs, including septic peritonitis secondary to dehiscence in 4 dogs. The median progression free interval was 54 days, and the median survival time (MST) was 178 days (range, 1-1902). According to multivariable analysis results, experiencing an intraoperative complication was associated with an increased risk of death (hazard ratio [HR] 3.5, 95% CI 1.1-9.8, P = .005), and administration of adjuvant chemotherapy correlated with an improved survival (HR 0.4, 95% CI 0.2-0.9, P = .03)., Conclusion: In this population of dogs, MST exceeded historically reported data, major postoperative complication rates were comparable to established literature, and administration of adjuvant chemotherapy was associated with improved survival., Clinical Significance: Results from this study may be used to counsel owners more accurately regarding prognosis for dogs undergoing surgical excision for gastric carcinoma., (© 2019 The American College of Veterinary Surgeons.)

Objective: To evaluate long-term outcomes and identify factors associated with death or the need for revision surgery in dogs with permanent tracheostomies (PTs)., Design: Retrospective cohort study., Animals: 69 client-owned dogs that received a PT between January 2002 and June 2016 at 1 of 4 veterinary teaching hospitals., Procedures: Medical records were reviewed, and data extracted included signalment, history, clinical signs, radiographic and laryngeal examination findings, presence of esophageal abnormalities, date and reason for receiving a PT, postoperative complications, cause of death, and survival time. Dogs surviving < 2 weeks after receiving a PT were excluded., Results: Major complications occurred in 42 of 69 (61%) dogs, with aspiration pneumonia (13 [19%]), skinfold occlusion (13 [19%]), and stoma stenosis (12 [17%]) being most common. Revision surgery was performed in 24 of 69 (35%) dogs, most commonly because of stoma stenosis or skinfold occlusion (9/24 [38%] each). Brachycephalic dogs were more likely (OR, 3.5; 95% confidence interval, 1.2 to 10.2) to require revision surgery than were nonbrachycephalic dogs. The overall median survival time was 1,825 days, and dogs that received corticosteroids before receiving a PT, had tracheal collapse, or were older had shorter survival times., Conclusions and Clinical Relevance: Results of the present study indicated that creation of a PT was a viable treatment option for obstructive upper airway diseases in dogs and that long-term survival after receiving a PT was possible; however, a PT may not reduce the risk of aspiration pneumonia in dogs.

Sentinel lymph node mapping and biopsy are important parts of oncologic staging in human medicine. Sentinel lymph node mapping enables identification of the first lymph node to receive lymphatic drainage while avoiding unnecessary lymph node dissection. Anal sac adenocarcinoma is the most common malignant neoplasm of the canine perineal area. For dogs with anal sac adenocarcinoma, lympadenectomy and metastasis to the iliosacral lymphocentrum are negative prognostics indicators. The objectives of this prospective, two by two, crossover pilot study were to establish the feasibility of lymphoscintigraphy using Technetium-99 sulfur colloid of the canine anal sac of healthy dogs, compare two injection techniques, and the time for identification of sentinel lymph nodes using each technique. We hypothesized that both intramural and perimural injections of the canine anal sac would identify similar sentinel lymph node drainage. The sentinel lymph node was identified in all dogs using either technique. Intramural injection of the canine anal sac showed radiopharmaceutical uptake faster than perimural injection technique (P = 0.040). There was concordance between intramual and perimural techniques for the sentinel lymph node identified in 50% of cases. A sacral lymph node was identified as sentinel in three of eight dogs (37.5%). Lymphoscintigraphy of the canine anal sac is safe and feasible in normal dogs; however, the method of injection technique seems to have a significant effect on the sentinel lymph node identified., (© 2018 American College of Veterinary Radiology.)

Objective: To assess histologic evaluation of mandibular lymph nodes (MLNs) and medial retropharyngeal lymph nodes (MRLNs) for metastatic disease during tumor staging for dogs with oral malignant melanoma (OMM) and oral squamous cell carcinoma (OSCC)., Design: Retrospective multi-institutional study., Animals: 27 dogs with OMM and 21 dogs with OSCC., Procedures: Medical record databases of 8 institutions were searched to identify dogs with OMM or OSCC that underwent unilateral or bilateral extirpation of the MLNs and MRLNs during the same procedure between January 2004 and April 2016. Information extracted from the records included signalment, primary mass location and size, diagnostic imaging results, histologic results for the primary tumor and all lymph nodes evaluated, and whether distant metastasis developed., Results: Prevalence of lymph node metastasis did not differ significantly between dogs with OMM (10/27 [37%]) and dogs with OSCC (6/21 [29%]). Distant metastasis was identified in 11 (41%) dogs with OMM and was suspected in 1 dog with OSCC. The MRLN was affected in 13 of 16 dogs with lymph node metastasis, and 3 of those dogs had metastasis to the MRLN without concurrent metastasis to an MLN. Metastasis was identified in lymph nodes contralateral to the primary tumor in 4 of 17 dogs that underwent contralateral lymph node removal., Conclusions and Clinical Relevance: Results indicated histologic evaluation of only 1 MLN was insufficient to definitively rule out lymph node metastasis in dogs with OMM or OSCC; therefore, bilateral lymphadenectomy of the MLN and MRLN lymphocentra is recommended for such dogs.

Objective: To determine the outcome and prognostic variables associated with long-term survival and complications in dogs undergoing hepatic lobectomy of the central division., Study Design: Multi-institutional retrospective case series., Animals: Sixty-one client-owned dogs with central division masses., Methods: Medical records of dogs undergoing hepatic lobectomy of the central division from January 1, 2000 to January 1, 2015 were reviewed for signalment, clinical signs, preoperative staging, preoperative cytology or biopsy results, date of procedure, location of mass, surgical technique, whether cholecystectomy or cholecystopexy was performed, complications, histopathologic diagnosis and margin evaluation, date of local recurrence or detection of metastatic disease, and survival., Results: Hilar resection was associated with increased intraoperative and postoperative complications. Intraoperative complications occurred in 29 dogs, with 20 dogs experiencing intraoperative hemorrhage. Nineteen dogs required transfusions. Immediate postoperative complications occurred in 20 dogs. Perioperative mortality rate was 11%, and 2-week mortality rate was 14.7%. The median survival time for dogs with hepatocellular carcinoma (HCC) was not reached. The 1- and 3-year censored survival rates for dogs with HCC was 82.1% and 82.1%, respectively. Margin status did not impact survival time., Conclusion: Hepatic lobectomy of the central division was associated with hemorrhage in approximately 33% of dogs, but there was a relatively low perioperative mortality rate. Hepatic lobectomy for HCC resulted in long-term survival, regardless of margin status., Clinical Significance: Surgeons should anticipate the requirement for blood products in dogs that may require hepatic lobectomy of the central division. Long-term survival can be expected after surgical treatment of HCC, regardless of margin status., (© 2019 The American College of Veterinary Surgeons.)

The purpose of this study was to evaluate owner perception of outcome following permanent tracheostomy (PT) in dogs. Medical records of dogs who received PT from 2002 to 2016 were reviewed. A questionnaire was given to owners verbally or by e-mail to ascertain their perception of their dog's outcome after PT. Median time to questionnaire administration from PT surgery was 608 days (64-3,708). Owner satisfaction after PT was high (89.7%), with the majority stating they would have the procedure performed again (79.5%). Owners reported an improvement in their dog's personality (30.8%) and increased activity (41%). Median survival time was 1,825 days (64-2,663), with 6 of 39 dogs (15.4%) alive at study end. Of the 33 dogs who died, 11 (33.3%) died from underlying respiratory conditions suspected to be related to the PT. The overall complication rate was 82.1%, with mucus secretion being the most common. Revision surgery was required in 30.8% of dogs (most commonly due to skin occlusion), and aspiration pneumonia occurred in 17.9% of dogs. Overall, owner satisfaction after PT in dogs is high despite intensive postoperative management, and long survival times can be achieved.

Objective: To describe the complications and outcome after total prostatectomy in dogs with histologically confirmed prostatic carcinoma., Study Design: Multi-institutional retrospective case series., Animals: 25 client-owned dogs., Methods: Medical records of dogs undergoing total prostatectomy were reviewed from 2004 to 2016. Data retrieved included signalment, presenting signs, preoperative clinical findings, laboratory data, diagnostic imaging, surgical technique, histologic diagnosis, postoperative complications, occurrence of postoperative metastasis, and survival., Results: Twenty-five dogs underwent total prostatectomy for prostatic carcinoma. Urinary anastomotic techniques included urethrourethral anastomosis in 14 dogs, cystourethral anastomosis in 9 dogs, ureterocolonic anastomosis in 1 dog, and anastomosis between the bladder neck and penile urethra in 1 dog. All dogs survived to discharge. Fifteen dogs were diagnosed with transitional cell carcinoma, 8 dogs with prostatic adenocarcinoma, 1 with prostatic cystadenocarcinoma, and 1 with an undifferentiated carcinoma. Permanent postoperative urinary incontinence was present in 8 of 23 dogs. The median survival time was shorter in dogs with extracapsular tumor extension compared with those with intracapsular tumors. The overall median survival time was 231 days (range, 24-1255), with 1- and 2-year survival rates equal to 32% and 12%, respectively., Conclusion and Clinical Significance: Total prostatectomy, combined with adjunct therapies, prolongs survival and lowers complication rates compared to previous reports of dogs with prostatic carcinoma. It should be noted, however, that case selection likely played a significant role in postoperative outcome., (© 2018 The American College of Veterinary Surgeons.)

Melanocytic neoplasms are common in dogs and frequently occur within the oral cavity or in haired skin. The behavior of melanocytic neoplasms is variable and depends on tumor location, size, and histopathologic features. This study compared cytopathology and histopathology of 32 lymph nodes from 27 dogs diagnosed with melanocytic neoplasms. Agreement between the original cytology report, cytology slide review, original histopathology report, and histopathology slide review was determined for each lymph node. A subset of lymph nodes was subjected to immunohistochemistry (Melan-A) and additional histochemical stains/techniques (Prussian blue, bleach) to assist in differentiation of melanocytes and melanophages. Agreement ranged from slight to fair for each of the variables evaluated with weighted kappa (κ w ) or kappa (κ) analysis (original cytology vs cytology review κ w = 0.24; original cytology vs original histopathology κ w = 0.007; original cytology vs histopathology review κ w = 0.23; cytology review vs original histopathology κ w = 0.008; cytology review vs histopathology review κ w = 0.006; and original histopathology vs histopathology review κ = 0.18). The diagnoses (metastatic, equivocal, or negative for metastasis) of the original report and slide review for both cytology and histopathology were not significantly correlated with survival in this population of patients. Overall, agreement between cytology and histopathology was poor even with a single clinical or anatomic pathologist performing slide review. Consensus between routine cytology and histopathology for staging of lymph nodes in patients with melanocytic neoplasms is poor and does not correlate with survival.

Objective: To determine the stiffness and load to failure of two different ostectomy configurations using canine mandibles., Study Design: Cadaveric biomechanical assessment., Animals: Paired mandibles (n = 30)., Methods: Standardized partial ostectomies were created on the alveolar surface of 30 mandibles. Samples were randomly assigned to right-angled (n = 15) or crescentic ostectomy (n = 15). Excision spanned the mesial aspect of the fourth premolar tooth to the distal aspect of first molar tooth. Mandibles were loaded to failure in three-point bending. The stiffness, displacement at maximum load, and load to failure were measured., Results: There was no significant difference in stiffness (p = 0.59), displacement at maximum load (p = 0.16) and load to failure (p = 0.76) between right-angled or crescentic ostectomy. Right-angled and crescentic ostectomy failed mostly by fracture through an empty alveolus (11/15 and 13/15, respectively)., Clinical Relevance: No significant differences in load to failure or stiffness between ostectomy techniques were observed. Crescentic ostectomy did not improve the acute load to failure for partial mandibulectomy. The empty alveolus served as a focal stress concentration point eliminating the potential mechanical advantage of a crescentic ostectomy.

Surgical oncology is experiencing rapid transition in veterinary medicine. Mast cell tumors and soft tissue sarcomas are two of the most common neoplasms in small animal patients. Clinicians should be familiar with the need for staging and the procedures involved in treating patients with these tumors. Clinicians should be comfortable with available adjuvant therapies and when to use them in certain patients., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: To determine the effectiveness of a vascular sealing technology on canine carotid arteries using various seal configurations to achieve maximal vessel security., Study Design: Ex-vivo study., Animals: Dogs (n = 20)., Methods: Carotid arteries (n = 40) were removed from the mid-cervical region of recently euthanatized dogs. Harvested vessels were closed with 2 circumferential ligatures (Group 1) or a vascular sealing device using 1 of 4 seal configurations of 1 or 2 seals combined with 1 or 2 machine activations/seal. The artery was instrumented to measure intraluminal pressure to evaluate the security of each seal during saline infusion. Maximum intraluminal pressure was recorded for each group, and time for application of each sealing protocol was compared using 1-way ANOVA and Tukey's test for multiple comparisons. Histologic features of the sealing protocols were evaluated., Results: Arterial closures for each group were effective in preventing leakage up to 300 mmHg. There was no significant difference in maximum intraluminal pressure between any group. A significant difference (P ≤ .001) was observed for time to seal creation between the groups using 1 and 2 seals. Histologic evaluation showed no differences between the different sealing protocols., Conclusion: Vessel sealing using a single seal created with a single activation cycle was adequate for sealing canine carotid arteries. Histologic examination did not demonstrate any disadvantages to multiple seals or multiple cycle activations., (© Copyright 2014 by The American College of Veterinary Surgeons.)

This study describes the effect of enteric biopsy closure orientation on circumference and volume of saline needed for leak testing. There were significant differences in circumference measurements at baseline, central circumference of longitudinally closed sites, and volume of saline for leak testing.