Objective:To describe the clinical presentation, perioperative variables, surgical management, and outcomes in cats that underwent surgery for biliary cystadenomas. Animals:21 cats met inclusion criteria. These cats had surgery for biliary cystadenomas between 2008 and 2023, with a corresponding histopathologic diagnosis. Clinical Presentation:Cats were reported as domestic shorthair (15 of 21), domestic longhair (3 of 21), Himalayan (1 of 21), Ragdoll (1 of 21), and Persian (1 of 21). This included 13 neutered males and 8 spayed females with a median age of 13 years. Cats most commonly presented with nonspecific clinical signs such as vomiting, weight loss, hyporexia, and lethargy. Cats were occasionally subclinical with a liver mass identified on physical examination or abdominal imaging. Results:Surgery was pursued based on a variety of factors, including comorbidities requiring surgery, features of the mass, and clinical signs attributed to the mass. Major surgical complications were uncommon, and the perioperative mortality rate was 10% (2 of 21). Three cats had concerns for malignant transformation on histopathology. The recurrence rate was 22% (4 of 18) for the cats with follow-up. The biliary cystadenoma was not the life-limiting issue for cats that survived the perioperative period. The median survival time was 570 days with 1-, 2-, and 3-year survival rates of 67%, 43%, and 15%, respectively. Clinical Relevance:Cats had positive short-term outcomes and long-term prognosis, and surgery should be considered for suspected biliary cystadenomas to obtain a definitive diagnosis and address associated morbidity. The potential for malignant transformation exists for feline biliary cystadenomas.

Purpose: Osteosarcoma is the most common primary malignancy of the skeleton. Despite advances in imaging modalities, neoadjuvant and adjuvant chemotherapy, and limb-sparing surgery over the past decades, there has been a general lack of improvement in survival rates. Tumor recurrence and metastases are associated with a worse prognosis, and complete tumor excision is critical. The use of real-time imaging could facilitate the acquisition of tumor-free surgical margins. Spontaneous osteosarcoma in dogs is an established translational model of human osteosarcoma.Experimental Design: In this study, 12 dogs with spontaneous appendicular osteosarcoma received a cathepsin-targeted quenched activity-based probe (VGT-309) intravenously 16 to 20 hours before amputation. The limb was imaged at four levels of dissection, and the margins of near-infrared fluorescence were marked for comparison with histopathology and preoperative MRI.Results: All appendicular tumors fluoresced on cross-section of the bone, and the extent of fluorescence coincided with MRI and histopathologic margins, with variability associated with necrosis. All tumors had visible fluorescence through cortical bone, although this did not consistently reflect intramedullary extension of the tumor. Necrotic tumor regions did not fluoresce.Conclusions: These data support the safety and feasibility of VGT-309 as a tool for evaluating the tissue extent of canine osteosarcoma and spur investigation for intraoperative detection of osteosarcoma during limb-sparing surgery in humans. Due to frequent intramedullary tumor extension and inconsistent fluorescence through unaffected cortical bone, this modality is likely most appropriate for assessing residual tumor following planned resection. Caution should be exercised when significant tumor necrosis is present.

Nasal biopsies from 21 dogs diagnosed with chondro-osseous respiratory epithelial adenomatoid hamartomas or respiratory epithelial adenomatoid hamartomas were reviewed. Associated lesions included angiomatous tissue (4/21), seromucinous gland proliferation (2/21), and polyps (3/21), and all had chronic inflammation. Dogs had epistaxis (14/21), sneezing (9/21), decreased airflow (8/21), congestion (6/21), and discharge (5/21). In addition to a mass lesion, computed tomography findings (n = 19) included turbinate lysis (10/19), cribriform plate and orbit erosion (4/19), and contralateral extension (8/19). In 16 dogs with outcome data collected 0-49 months after diagnosis, 13 had continued respiratory symptoms, 11 of which received medical management; 2 of the 3 dogs with improvement had radiotherapy/radiofrequency procedures after biopsy. Eight dogs were alive, 5 were euthanized due to the hamartoma (median survival 9.3 months), 2 died from unknown causes, and 1 died from a seizure. Nasal hamartomas are often locally destructive mass lesions that cause recurrent upper respiratory symptoms and may require more aggressive therapeutic interventions for disease control. Diagnosing nasal hamartomas requires integrating the clinical history, imaging results, adequate biopsy sampling of the mass, and the presence of characteristic histologic features.

Case summary A 2-year-old female spayed domestic shorthair cat was presented for evaluation of severe thickening of the proximal duodenum identified on abdominal ultrasound after a 1-year history of vomiting. At surgery, a proximal duodenal mass encompassed the areas of the major and minor duodenal papillae. A gastrojejunostomy was performed to bypass the proximal duodenum and maintain the integrity of the major duodenal papilla. Histopathology revealed changes consistent with feline eosinophilic sclerosing fibroplasia. The cat was treated with prednisolone and survived for 2.5 years. It was euthanized for bronchopneumonia. Relevance and novel information This case report describes a surgical approach for cats with lesions involving the pylorus and proximal duodenum. Gastrojejunostomy provided a therapeutic option that preserved exocrine pancreatic and biliary secretion in this cat.

OBJECTIVE:The aim of this study was to develop and describe pre- and intra-operative sentinel lymph node (SLN) mapping techniques in dogs with thyroid carcinoma. STUDY DESIGN:A prospective, pilot clinical trial was performed. ANIMALS:Six client-owned dogs with unilateral thyroid carcinoma and no overtly metastatic locoregional lymph nodes (LNs) were enrolled. METHODS:All dogs underwent preoperative indirect computed tomography (CT)-lymphography (CTL) with peritumoral iohexol injection and intraoperative SLN mapping with peritumoral injection of a visible dye (methylene blue [MB]) and near-infrared (NIR) fluorescent dye (indocyanine green [ICG]). Subsequent LN extirpation and routine thyroidectomy were performed. All excised tissues were evaluated histologically. RESULTS:Pre- and intra-operative SLN mapping identified at least one SLN in all dogs. A median of one SLN (range, 1-2) was identified on both CTL and intraoperative SLN mapping. Identified SLNs included medial retropharyngeal, cranial deep cervical, and superficial cervical LNs. Variability between pre- and intra-operative SLN findings occurred in 3/6 dogs. A median of two LNs (range, 1-3) were extirpated for each dog. Metastatic carcinoma was diagnosed in extirpated LNs in 2/6 dogs and 3/12 extirpated LNs. CONCLUSION:In this pilot study, preoperative CTL and intraoperative MB and ICG/NIR allowed for identification of SLNs in dogs with thyroid carcinoma. CLINICAL SIGNIFICANCE:Sentinel lymph nodes were identified and extirpated using the described techniques, with nodal metastasis identified in a subset of these dogs due to SLN mapping. Large-scale, powered studies are needed to accurately determine the incidence and prognostic significance of nodal metastasis identified by SLN mapping and extirpation in dogs with thyroid carcinoma.

OBJECTIVE:To compare bacteria cultured at the time of total ear canal ablation (TECA) to bacteria cultured from post-TECA incisional dehiscence. STUDY DESIGN:Multicenter retrospective case series. ANIMAL POPULATION:Dogs (n = 12) with incisional dehiscence following TECA. METHODS:Medical records of dogs that had a TECA between August 1, 2015, and August 1, 2023, with a subsequent incisional dehiscence within 5 weeks of surgery were reviewed. Aerobic cultures were performed at the time of surgery and time of incisional dehiscence. RESULTS:The most common organisms cultured from TECA samples included Staphylococcus spp. (5/12, 41.7%), Enterococcus spp. (3/12, 25%), Streptococcus spp. (3/12, 25%), Escherichia coli (2/12, 16.7%), and Corynebacterium spp. (2/12, 16.7%). The organisms most commonly isolated from incisional dehiscences were Staphylococcus spp. (10/12, 83.3%) and Escherichia coli (5/12, 41.7%). The median time for incisional dehiscence was 11.5 days postoperatively (range, 2-34 days). The same single bacteria species, Staphylococcus schleiferi, was identified from the TECA and incisional dehiscence cultures in only one dog (1/12, 8.3%). In 6/12 (50%) dogs, the same bacteria were cultured before or during TECA and at the time of incisional dehiscence, but additional organisms were also identified. Antibiotic susceptibility patterns were different in four of seven dogs where the same bacteria were cultured prior to and during incisional dehiscence. CONCLUSION:Cultures performed during TECA were not predictive of culture results at the time of dehiscence. Antibiotic susceptibility patterns often changed when the same organism was cultured prior to and at incisional dehiscence. CLINICAL SIGNIFICANCE:Repeating cultures is essential to treat infectious incisional dehiscence following TECA appropriately.

The high incidence of nodal metastasis, variable lymphatic drainage patterns, and prognostic significance of nodal metastasis in dogs with apocrine gland anal sac adenocarcinoma (AGASACA) highlight the need for development of standardized techniques for lymph node staging in canine AGASACA. The aim of this study was to develop and describe the utility of pre- and intra-operative sentinel lymph node (SLN) mapping techniques for subsequent nodal extirpation and histologic assessment in dogs with AGASACA. A prospective clinical trial was performed as a pilot study. Eight client-owned dogs with unilateral AGASACA were enrolled. Preoperative contrast-enhanced ultrasound (CEUS) via transrectal ultrasound (TRUS) and CT-lymphography (CTL) was followed by intraoperative SLN mapping within 7 days utilizing a visible dye (methylene blue [MB]) and a near-infrared (NIR) fluorescent dye (indocyanine green [ICG]) with subsequent nodal extirpation and routine anal sacculectomy. In all dogs, preoperative CTL and intraoperative SLN mapping identified at least one SLN. Pre- and intra-operative findings differed in 4/8 dogs. Preoperative CEUS identified a SLN in 7/8 dogs, but the exact location of the SLN was indeterminate. Extirpated lymph nodes were metastatic in 2/8 dogs. Preoperative CTL and intraoperative MB and ICG were an effective combination of SLN mapping techniques in dogs with AGASACA. These techniques each provided unique advantages. Combined, they identified and guided extirpation of early metastatic lymph nodes. Large-scale, prospective studies utilizing the techniques described are needed to accurately determine the incidence and significance of early/occult nodal metastasis in canine AGASACA.

A potbelly pig was evaluated for anorexia and icterus. Clinicopathologic abnormalities suggested an active inflammatory hepatobiliary process. Ultrasound and CT of the abdomen revealed an extrahepatic biliary obstruction of the common bile duct (CBD). Surgical exploration and choledochotomy revealed a markedly dilated CBD containing a large volume of intraluminal inspissated biliary material. This case report describes the imaging findings of an extrahepatic biliary obstruction secondary to abscessation within the CBD in a pig.

Lung cancer, the most common cause of cancer-related death in the United States, requires advanced intraoperative detection methods to improve evaluation of surgical margins. In this study we employed DDAO-arachidonate (DDAO-A), a phospholipase A2 (PLA2) activatable fluorophore, designed for the specific optical identification of lung cancers in real-time during surgery. The in vitro fluorescence activation of DDAO-A by porcine sPLA2 was tested in various liposomal formulations, with 100 nm extruded EggPC showing the best overall characteristics. Extruded EggPC liposomes containing DDAO-A were tested for their stability under various storage conditions, demonstrating excellent stability for up to 4 weeks when stored at -20 degrees C or below. Cell studies using KLN 205 and LLC1 lung cancer cell lines showed DDAO-A activation was proportional to cell number. DDAO-A showed preferential activation by human recombinant cPLA2, an isoform highly specific to arachidonic acid-containing lipids, when compared to a control probe, DDAO palmitate (DDAO-P). In vivo studies with DBA/2 mice bearing KLN 205 lung tumors recapitulated these results, with preferential activation of DDAO-A relative to DDAO-P following intratumoral injection. Topical application of DDAO-A-containing liposomes to human (n = 10) and canine (n = 3) lung cancers ex vivo demonstrated the preferential activation of DDAO-A in tumor tissue relative to adjacent normal lung tissue, with fluorescent tumor-to-normal ratios (TNR) of up to 5.2:1. The combined results highlight DDAO-A as a promising candidate for clinical applications, showcasing its potential utility in intraoperative and back-table imaging and topical administration during lung cancer surgeries. By addressing the challenge of residual microscopic disease at resection margins and offering stability in liposomal formulations, DDAO-A emerges as a potentially valuable tool for advancing precision lung cancer surgery and improving curative resection rates.

BACKGROUND:The objectives of this study were to: (i) Determine whether operable primary liver tumors were associated with prolongations in prothrombin time (PT) and activated partial thromboplastin time (aPTT) and (ii) determine if these secondary hemostatic abnormalities were more prevalent with specific liver tumors. STUDY DESIGN:Multi-institutional retrospective study. ANIMAL POPULATION:Dogs (n = 359) undergoing liver lobectomy for a primary liver tumor with a preoperative coagulation panel. METHODS:Data was identified via electronic medical record review at eight veterinary teaching hospitals. Baseline dog characteristics, coagulation panel values, platelet count, emergency versus non-emergency procedure, whether the dogs received transfusion(s) of a blood product, liver lobe removed, and histopathological diagnosis were extracted from the medical record. Chi-square analysis was used to compare categorical variables between groups. Continuous variables were assessed for normality using the Shapiro-Wilk test. RESULTS:A total of 74 of 359 dogs (20.6%) had a prolongation in either PT or aPTT preoperatively. A total of 20 of 359 dogs (5.6%) were found to have prolongation of both PT and aPTT. Hemangiosarcoma was the only histopathological diagnosis associated with concurrent prolongations of both PT and aPTT (p < .001) in 6/16 (37.5%) dogs. CONCLUSION:Coagulation panels including PT and aPTT are unlikely to detect substantial deficiencies in secondary hemostasis in most dogs with primary liver tumors except in dogs with a histopathological diagnosis of hemangiosarcoma. CLINICAL SIGNIFICANCE:PT and aPTT testing is low yield as an elective preoperative screening test in dogs with primary liver tumors except in dogs where there is a hemoabdomen or high suspicion for hepatic hemangiosarcoma.

Clinical case presentations detail unique and clinically relevant anatomical features about the canine and feline head and neck, including aspects of dentition, nasal passages, ear, eye, thyroid, vertebrae, and the central nervous system.

Abstract Purpose: Fluorescence-guided surgery using tumor-targeted contrast agents has been developed to improve the completeness of oncologic resections. Quenched activity–based probes that fluoresce after covalently binding to tumor-specific enzymes have been proposed to improve specificity, but none have been tested in humans. Here, we report the successful clinical translation of a cathepsin activity–based probe (VGT-309) for fluorescence-guided surgery. Experimental Design: We optimized the specificity, dosing, and timing of VGT-309 in preclinical models of lung cancer. To evaluate clinical feasibility, we conducted a canine study of VGT-309 during pulmonary tumor resection. We then conducted a randomized, double-blind, dose-escalation study in healthy human volunteers receiving VGT-309 to evaluate safety. Finally, we tested VGT-309 in humans undergoing lung cancer surgery. Results: In preclinical models, we found highly specific tumor cell labeling that was blocked by a broad spectrum cathepsin inhibitor. When evaluating VGT-309 for guidance during resection of canine tumors, we found that the probe selectively labeled tumors and demonstrated high tumor-to-background ratio (TBR; range: 2.15–3.71). In the Phase I human study, we found that VGT-309 was safe at all doses studied. In the ongoing Phase II trial, we report two cases in which VGT-309 localized visually occult, non-palpable tumors (TBRs = 2.83 and 7.18) in real time to illustrate its successful clinical translation and potential to improve surgical management. Conclusions: This first-in-human study demonstrates the safety and feasibility of VGT-309 to label human pulmonary tumors during resection. These results may be generalizable to other cancers due to cathepsin overexpression in many solid tumors.

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.

A recessed vulva is a conformational abnormality that predisposes affected dogs to urinary tract infections. An episioplasty can be recommended for correction of this abnormality when medical management of recurrent urinary tract infection fails. The objective of this study was to investigate the type and incidence of urogenital abnormalities visualized by cystoscopy in dogs presenting for episioplasty. Medical records of 29 dogs that presented for an episioplasty and had a concurrent or prior cystoscopy were reviewed. Eleven of the 29 dogs had urogenital abnormalities diagnosed on cystoscopic evaluation, and 1 dog was diagnosed with a urogenital abnormality during vaginal examination while under general anesthesia. Ten of the dogs with urogenital abnormalities had a corrective procedure performed, 8 of which were cystoscopically assisted. Cystoscopy provides the ability to directly visualize the urinary tract and obtain samples for biopsy and culture and facilitates correction of some anatomic abnormalities that may predispose the patient to developing recurrent urinary tract infections. Cystoscopy should be considered as a routine part of a thorough evaluation of the urinary tract in cases presenting for episioplasty.

OBJECTIVE To determine the severity of nasopharyngeal collapse in brachycephalic dogs before and after corrective airway surgery. ANIMALS Twenty-three brachycephalic dogs (21 with clinical signs referrable to the upper airway) and nine clinically normal nonbrachycephalic dogs (controls). METHODS Dogs were evaluated with fluoroscopy awake and standing with the head in a neutral position. The magnitude of nasopharyngeal collapse was measured as the maximum reduction in the dorsoventral dimension of the nasopharynx during respiration and expressed as a percentage. Brachycephalic dogs were anesthetized, the airway evaluated, and corrective upper airway surgery (alaplasty, staphylectomy, sacculectomy, tonsillectomy) was performed. A cohort (n = 11) of the surgically treated brachycephalic dogs had fluoroscopy repeated a minimum of 6 weeks after surgery. RESULTS Median preoperative reduction in the dorsoventral dimensions of the nasopharynx was greater in brachycephalic dogs (65%; range: 8-100%) than in controls (10%; range: 1-24%, p = .0001). Surgery did not improve the reduction in dorsoventral diameter of the nasopharynx during respiration in brachycephalic dogs (n = 11) postoperatively (p = .0505). CONCLUSION AND CLINICAL SIGNIFICANCE Nasopharyngeal collapse was a common and sometimes severe component of brachycephalic airway obstruction syndrome in the cohort of dogs evaluated. The lack of significant postoperative improvement may represent a type II error, a failure to adequately address anatomical abnormalities that increase resistance to airflow, or inadequate upper airway dilator muscle function in some brachycephalic dogs.

Gorilla Glue contains methylene diphenyl diisocyanate that expands significantly and hardens once exposed to moisture. Case reports of methylene diphenyl diisocyanate glue ingestion in dogs document gastrointestinal foreign body formation and mechanical obstruction. Medical record queries from four veterinary hospitals identified 22 dogs with Gorilla Glue ingestion. Records were evaluated retrospectively to characterize clinical presentation, diagnostic findings, treatment, and patient outcome. Vomiting was the most common clinical sign (n = 11), with a median time from ingestion to presentation of 42 hr. Abnormal abdominal palpation (e.g., pain) was the most reported examination finding (n = 13). Radiographs were performed in 18/22 dogs, with Gorilla Glue expansion described as granular or mottled soft tissue with gas in the stomach. In 73% (11/15) of dogs requiring surgery, history, clinical findings, and survey abdominal radiographs sufficed to proceed with celiotomy. Surgical removal of the Gorilla Glue foreign body was performed via gastrotomy (n = 14) or gastrotomy and duodenotomy (n = 1). Endoscopic removal was performed in one dog. One dog with suspected mechanical obstruction was euthanized owing to financial constraints. Remaining cases were managed conservatively (n = 5). Short-term prognosis following appropriate fluid therapy and surgical or endoscopic removal was very good.

An 8-month-old spayed female Labrador retriever dog was evaluated for regurgitation 6 months after surgery for a suspected vascular ring anomaly. The dog had a history of regurgitation and slow development as a puppy. An initial left-sided exploratory thoracotomy was unsuccessful in identifying and treating a vascular ring anomaly. The dog was subsequently presented to the PennVet Emergency Service for regurgitation. Thoracic radiography showed cranial thoracic esophageal dilation and an esophageal foreign body that was then removed endoscopically. Subsequent computed tomographic (CT) angiography revealed a double aortic arch. A left 4th intercostal space thoracotomy was performed. The smaller left aortic arch and a left ligamentum arteriosum were ligated and transected. The dog recovered uneventfully and was healthy at the 1-month follow-up visit. This is the 5th reported successful surgical correction of a double aortic arch in a dog. Computed tomographic angiography was essential in diagnosis and surgical planning. Key clinical message: Although uncommon, double aortic arches can occur and present a diagnostic and surgical challenge when a persistent right aortic arch is suspected. Computed tomographic angiography provides an accurate preoperative diagnosis and allows for surgical planning.

Perioperative administration of desmopressin has shown to significantly decrease rates of local recurrence and metastasis, and increase survival times in dogs with grade II and III mammary carcinomas. The objective of this study was to compare the oncologic outcome of cats with mammary carcinoma treated with bilateral mastectomy with or without perioperative administration of desmopressin. Medical records from nine veterinary institutions were searched to identify cats diagnosed with mammary carcinoma treated with bilateral mastectomy. Sixty cats treated with single-session or staged bilateral mastectomy were included. There were no significant differences in oncologic outcomes found between cats treated and not treated with desmopressin. No adverse effects were seen in any of the cats treated with perioperative desmopressin. Postoperative complications occurred in 18 cats (38.3%) treated with single-session bilateral mastectomy and in three cats (23.1%) treated with staged bilateral mastectomy (P = .48). Histologic grade and a modification of a proposed five-stage histologic staging system were both prognostic for disease-free interval. Incomplete histologic excision was associated with significantly increased rates of metastasis and tumour progression, and a shorter median survival time (MST). Cats that developed local recurrence also had a significantly shorter MST. The results of this study do not support the use of perioperative desmopressin to improve outcome when performing bilateral mastectomy for the treatment of mammary carcinoma in cats.

OBJECTIVETo evaluate complication rates for various types of mastectomy procedures, identify factors associated with an increased risk of complications, and determine the consequences of such complications.ANIMALS140 female dogs that underwent 154 separate mastectomy procedures to treat mammary gland tumors.PROCEDURESMedical records of dogs in the Penn Vet Shelter Canine Mammary Tumor Program from July 2009 to March 2015 were reviewed. Data regarding signalment, tumor characteristics (ie, number and size, benign or malignant, and bilateral or unilateral), mastectomy type, anesthesia time, concurrent ovariohysterectomy or ovariectomy, surgeons' qualifications, antimicrobial administration after surgery, postoperative placement of surgical drains, and complications (seroma, abscess, dehiscence, or infection) were collected. Complications that required hospitalization were recorded. Fisher exact tests were used to evaluate associations between variables of interest and complications. Multivariable analysis was used to identify factors independently associated with an increased risk of complications.RESULTSComplication rate following all mastectomy procedures was 16.9% (26/154); of these, 9 (34.6%) required hospitalization. High body weight, undergoing bilateral mastectomy, and postoperative antimicrobial administration were associated with significantly increased odds of complications. The odds of complications associated with postoperative antimicrobial administration, however, varied according to mastectomy type; dogs undergoing chain mastectomy that did not receive antimicrobials postoperatively had the highest odds of developing complications. Dogs undergoing concurrent ovariohysterectomy or ovariectomy had significantly decreased odds of complications.CONCLUSIONS AND CLINICAL RELEVANCEPreviously spayed dogs with a large body size that underwent the most extensive mastectomy procedures had increased odds of having postoperative complications.