Genomic analysis across 53 canine cancer types reveals novel mutations and high clinical actionability potential.

A genomic understanding of the oncogenic processes and individual variability of human cancer has steadily fueled improvement in patient outcomes over the past 20 years. Mutations within tumour tissues are routinely assessed through clinical genomic diagnostic assays by academic and commercial laboratories to facilitate diagnosis, prognosis and effective treatment stratification. The application of genomics has unveiled a wealth of mutation-based biomarkers in canine cancers, suggesting that the transformative principles that have revolutionized human cancer medicine can be brought to bear in veterinary oncology. To advance clinical genomics and genomics-guided medicine in canine oncology, we have developed and validated a canine cancer next-generation sequencing gene panel for the identification of multiple mutation types in clinical specimens. With this panel, we examined the genomic landscapes of 828 tumours from 813 dogs, spanning 53 cancer types. We identified 7856 alterations, encompassing copy number variants, single nucleotide variants, indels and internal tandem duplications. Additionally, we evaluated the clinical utility of these alterations by incorporating a biomarker framework from comprehensive curation of primary canine literature and inferences from human cancer genomic biomarker literature and clinical diagnostics. Remarkably, nearly 90% of the cases exhibited mutations with diagnostic, prognostic or therapeutic implications. Our work represents a thorough assessment of genomic landscapes in a large cohort of canine cancers, the first of its kind for its comprehensive inclusion of multiple mutation types and structured annotation of biomarkers, demonstrating the clinical potential of leveraging mutation-based biomarkers in veterinary oncology.

Pathology in Practice.

In collaboration with the American College of Veterinary Pathologists.

Comparative Review of Malignant Melanoma and Histologically Well-Differentiated Melanocytic Neoplasm in the Oral Cavity of Dogs.

Oral malignant melanoma (OMM) is the most common neoplasm of the canine oral cavity. It is characterized by its aggressive local disease as well as its high rate of lymphatic invasion and distant metastasis. OMM carries a poor prognosis, with most patients succumbing to the disease due to progression of the neoplasm. Histopathologically, OMM is characterized by significant nuclear atypia, a mitotic index of greater than 4/10 hpf, and evidence of vascular invasion or metastasis. Clinically, these lesions can become locally invasive, causing lysis of bones and severe inflammation of the surrounding soft tissue. With time, these lesions can spread to the regional lymph node and to the lungs and other organs. Prognosis can vary depending on the size of the primary tumor, regional node involvement, and distant metastatic disease; however, multiple studies report a relatively short median survival time ranging from less than 4 months to 8 months. Histologically well- differentiated melanocytic neoplasms (HWDMN) are a variant of OMM and sometimes referred to as canine oral melanocytic neoplasms of low malignant potential. Unlike OMM, patients with HWDMN have longer survival times. Histopathologically, HWDMNs have well-differentiated melanocytes with a low mitotic index of 3 or less per 10 hpf and minimal nuclear atypia. HWDMNs have better prognosis with a mean survival time of up to 34 months. This article is a comparative review of OMM and its less aggressive counterpart.

Evaluation of novel serological markers and autoantibodies in dogs with inflammatory bowel disease.

BACKGROUND: The use of serological markers to diagnose inflammatory bowel disease (IBD) in humans is well-established. Because of the frequency of IBD in dogs and resources required for its diagnosis with current methods, new approaches are desired. OBJECTIVE: The goal is to evaluate novel serologic markers to differentiate clinical cohorts in dogs with gastrointestinal (GI) disease and assess their potential to develop a serum-based IBD diagnostic test. ANIMALS: Seventy dogs diagnosed with biopsy-confirmed IBD, 23 dogs with non-IBD predominantly acute GI diseases, and 58 normal dogs. METHODS: Prospective control study. ELISA methods were developed to detect autoantibodies to polymorphonuclear leukocytes (APMNA) and calprotectin (ACNA), antibodies against gliadins (AGA), microbial outer membrane porin C (ACA), and flagellins (AFA) isolated from diseased dogs based on clinical and histopathological scoring. RESULTS: IBD dogs displayed a 39%-76% prevalence of seropositivity against selected serologic markers that markedly decreased to 0%-13% in non-IBD and normal dogs. ROC analysis showed statistical significance in differentiating the cohorts, with seropositivity against OmpC being the highest single performance marker. The combination of markers such as OmpC and APMNA reached specificities of 93%-99% and 79%-98% and sensitivities of 76%-97% and 66%-86% when comparing IBD versus normal cohorts and non-IBD cohorts, respectively. CONCLUSION AND CLINICAL IMPORTANCE: Seropositivity of canine immunoglobulins A against selected serologic markers in dogs appears promising in the detection and differentiation of IBD versus other acute GI conditions. Among them, antibody reactivity to Escherichia coli OmpC and canine autoantibodies against polymorphonuclear leukocytes displayed the highest single marker discriminating performance.

Mucus Retention Cyst of the Soft Palate in a Dog.

A 10 yr old 6.6 kg (14.5 lb) castrated male Chihuahua was referred to the Alta Vista Animal Hospital for evaluation of a mass of the soft palate. The cystic structure was bluntly dissected from the soft palate submucosal tissue, and the dog recovered from surgery and anesthesia without complication. Histopathology revealed salivary tissue with a large multiloculated cyst lined by a single layer of cystic and dilated cuboidal epithelium. Follow up 7 mo after surgery revealed complete resolution of clinical signs with no evidence of local recurrence. To the authors' knowledge, this is the first confirmed report of a mucus retention cyst in a dog.

Apocrine gland anal sac adenocarcinoma in cats: 30 cases (1994-2015).

OBJECTIVE To describe the signalment, clinical signs, biological behavior, and outcome for cats with apocrine gland anal sac adenocarcinoma (AGASACA) that underwent surgical excision. DESIGN Retrospective case series. ANIMALS 30 client-owned cats. PROCEDURES Databases of 13 Veterinary Society of Surgical Oncology member-affiliated institutions were searched for records of cats with a histologic diagnosis of AGASACA that underwent tumor excision. For each cat, information regarding signalment, clinical signs, diagnostic test results, treatment, and outcome was extracted from the medical record. The Kaplan-Meier method was used to determine median time to local recurrence (TLR), disease-free interval (DFI), and survival time. Cox regression was used to identify factors associated with TLR, DFI, and survival time. RESULTS Perineal ulceration or discharge was the most common clinical sign in affected cats. Eleven cats developed local recurrence at a median of 96 days after AGASACA excision. Incomplete tumor margins and a high nuclear pleomorphic score were risk factors for local recurrence. Nuclear pleomorphic score was negatively associated with DFI. Local recurrence and a high nuclear pleomorphic score were risk factors for death. Median DFI and survival time were 234 and 260 days, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that, in cats, perineal ulceration or discharge should raise suspicion of AGASACA and prompt rectal and anal sac examinations. Local recurrence was the most common life-limiting event in cats that underwent surgery for treatment of AGASACA, suggesting that wide margins should be obtained whenever possible during AGASACA excision. Efficacy of chemotherapy and radiation therapy for treatment of cats with AGASACA requires further investigation. (J Am Vet Med Assoc 2019;254:716-722).

Clinicopathological Correlation and Prevalence of Increased Copper in Canine Hepatic Cytology.

Special staining and grading of canine liver cytology samples aids in detection of increased copper content. The prevalence of copper in routine diagnostic liver cytology samples, clinical findings associated with high cytologic copper (cCu) grade, and the correlation between cCu grade and histologic findings, including histologic copper (hCu) grade, are unknown. This data may be helpful in ascertaining when to determine a cCu grade and when interpreting cCu grade. Clinical data and available archived hepatic histologic and cytologic samples from 198 dogs were collected, evaluated, rhodanine stained, and graded for copper. Prevalence of increased cCu >5 in a randomly collected group of 163 individuals, and the correlation between cCu and clinical data (n = 198), hCu grade (n = 37), or findings on hematoxylin and eosin-stained hepatic sections (n = 32) were evaluated. The observed prevalence was 1.23%. Dogs with elevated alanine transaminase >180 IU/L or aspartate transaminase >90 IU/L and patients who subsequently had hepatic copper quantification were statistically more likely to have pathologic levels of copper detected by cytology. There was significant and modest correlation between cCu and hCu, interface hepatitis, portal inflammation, and fibrosis. Evidence of hepatocellular leakage may be indications for determination of cCu.

Retrospective evaluation of toceranib phosphate (Palladia®) use in the treatment of gastrointestinal stromal tumors of dogs.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are uncommon intestinal neoplasms in the dog. Literature regarding adjunctive therapy for GISTs in dogs is sparse. High-risk GISTs in humans respond to tyrosine kinase inhibition in the adjuvant setting. OBJECTIVES: To review cases of toceranib phosphate use in dogs with GISTs and provide initial assessment of possible biological activity. A secondary aim was to evaluate patient and tumor characteristics for possible prognostic value. ANIMALS: Twenty-seven dogs with confirmed GISTs based on histopathology and immunohistochemistry treated with toceranib. METHODS: Retrospective study in which cases of toceranib use in dogs with GIST were solicited using the American College of Veterinary Internal Medicine Oncology and Small Animal Internal Medicine listservs. RESULTS: Five of 7 dogs with gross disease experienced clinical benefit (71%; 3 complete responses, 1 partial response, 1 stable disease). These included 2 dogs with durable responses after toceranib discontinuation. Median progression-free interval (PFI) in dogs with gross disease was 110 weeks (range, 36-155 weeks). Median PFI in dogs with microscopic disease was 67 weeks (range, 9-257 weeks). Metastasis at diagnosis (P = 0.04) and high mitotic index (P < 0.001) were associated with shorter PFI in toceranib-treated dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Biological activity of toceranib is evident in dogs with gross disease. Metastasis of GIST at diagnosis, as well as high tumor mitotic index, was associated with shorter PFI in toceranib-treated dogs. Larger studies are needed to define postsurgical risk and refine the use of toceranib in dogs with gross and microscopic GIST.

Safety of an Oncolytic Myxoma Virus in Dogs with Soft Tissue Sarcoma.

Many oncolytic viruses that are efficacious in murine cancer models are ineffective in humans. The outcomes of oncolytic virus treatment in dogs with spontaneous tumors may better predict human cancer response and improve treatment options for dogs with cancer. The objectives of this study were to evaluate the safety of treatment with myxoma virus lacking the serp2 gene (MYXVΔserp2) and determine its immunogenicity in dogs. To achieve these objectives, dogs with spontaneous soft tissue sarcomas were treated with MYXVΔserp2 intratumorally (n = 5) or post-operatively (n = 5). In dogs treated intratumorally, clinical scores were recorded and tumor biopsies and swabs (from the mouth and virus injection site) were analyzed for viral DNA at multiple time-points. In all dogs, blood, urine, and feces were frequently collected to evaluate organ function, virus distribution, and immune response. No detrimental effects of MYXVΔserp2 treatment were observed in any canine cancer patients. No clinically significant changes in complete blood profiles, serum chemistry analyses, or urinalyses were measured. Viral DNA was isolated from one tumor swab, but viral dissemination was not observed. Anti-MYXV antibodies were occasionally detected. These findings provide needed safety information to advance clinical trials using MYXVΔserp2 to treat patients with cancer.

Dedifferentiated Chondrosarcoma in the Dog and Cat: A Case Series and Review of the Literature.

This retrospective case series describes seven dogs and one cat diagnosed with dedifferentiated chondrosarcoma, an uncommon, aggressive variant of chondrosarcoma. The purpose of the study is to describe clinical, imaging, and histopathological findings of this tumor. Medical records and the diagnostic laboratory database at Colorado State University from 2000 to 2015 were reviewed and complete medical records were available for the eight animals in this report. Similar to what has been reported in people, poor long-term survival and high metastatic rate, particularly to the lungs, was observed in our case series. A bimorphic pattern on imaging (radiographs, computed tomography, and MRI) consisting of mineralized and nonmineralized areas was seen mirroring the high-grade sarcomatous component adjacent to a low-grade chondroid component seen histopathologically. A review of the human literature including suspected etiology, imaging findings, histopathology, and survival times with various treatment options is presented. This article describes the first reported cases of dedifferentiated chondrosarcoma in the veterinary literature. Early accurate recognition could lead to treatment plans tailored to this variant.

Malignant collision tumors in two dogs.

CASE DESCRIPTION A 13-year-old Labrador Retriever with a 4-cm-diameter ulcerated perianal mass and a 12-year-old Golden Retriever with a 5-cm-diameter ulcerated caudolateral abdominal mass were brought to a referral oncology practice for evaluation of the dermal masses. Both masses were resected with wide margins without reported postoperative complications. For both dogs, a diagnosis of collision tumor was made. The database of the Veterinary Diagnostic Laboratories at Colorado State University was searched for other examples of collision tumors in dogs. CLINICAL FINDINGS Histologic assessment of the masses revealed collision tumors in both patients. The perianal mass was diagnosed as a perianal gland carcinoma with adjacent hemangiosarcoma. The flank mass was diagnosed as a fibrosarcoma with an adjacent mast cell tumor. The university database search of sample submissions in 2008 through 2014 for the keywords collision, admixed, or adjacent yielded 37 additional cases of dogs with malignant nontesticular collision tumors. TREATMENT AND OUTCOME Both dogs were treated with surgery alone and received no adjunctive treatments. Both tumors were completely excised. There was no evidence of either local tumor recurrence or metastasis in the Labrador Retriever and the Golden Retriever at 1,009 and 433 days after surgery, respectively. CLINICAL RELEVANCE Collision tumors are rare, and there is minimal information regarding treatment recommendations and outcome for animals with collision tumors. On the basis of the 2 cases described in this report, the outcome associated with treatment of collision tumors may be similar to the expected outcome for treatment of any of the individual tumor types in dogs.

Optimising daytime deliveries when inducing labour using prostaglandin vaginal inserts.

OBJECTIVE: To determine induction start time(s) that would maximise daytime deliveries when using prostaglandin vaginal inserts. METHODS: Women enrolled into the Phase III trial, EXPEDITE (clinical trial registration: NCT01127581), had labour induced with either a misoprostol or dinoprostone vaginal insert (MVI or DVI). A secondary analysis was conducted to determine the optimal start times for induction by identifying the 12-h period with the highest proportion of deliveries by parity and treatment. RESULTS: Optimal start times for achieving daytime deliveries when using MVI appear to be 19:00 in nulliparae and 23:00 in multiparae. Applying these start times, the median time of onset of active labour would be approximately 08:30 for both parities and the median time of delivery would be the following day at approximately 16:30 for nulliparae and 12:00 (midday) for multiparae. Optimal start times when using DVI appear to be 07:00 for nulliparae and 23:00 for multiparae. Using these start times, the median time of onset of active labour would be the following day at approximately 04:00 and 11:50, and the median time of delivery would be approximately 13:40 and 16:10, respectively. CONCLUSIONS: When optimising daytime deliveries, different times to initiate induction of labour may be appropriate depending on parity and the type of retrievable prostaglandin vaginal insert used.

Splenic liposarcoma in dogs: 13 cases (2002-2012).

OBJECTIVE: To describe the clinical signs, diagnostic findings, surgical management, and outcome in dogs with splenic liposarcoma. DESIGN: Retrospective case series. ANIMALS: 13 client-owned dogs with splenic liposarcoma. PROCEDURES: Medical and pathology records of dogs with a histopathologic diagnosis of splenic liposarcoma from 2002 to 2012 were reviewed for the following data: clinical signs, CBC, biochemical profile, thoracic and abdominal imaging, surgical management, histologic grade, and outcome (local recurrence, distant metastasis, and survival time). Telephone interviews were conducted with referring veterinarians. RESULTS: The median survival time (MST) was 623 days (range, 1 to 1,283 days). In 5 dogs that died of splenic liposarcoma, survival times ranged from 42 to 369 days. Metastasis at the time of surgery was a negative prognostic indicator: the MST was 45 days for dogs with metastasis and 767 days for dogs without metastasis. Dogs with grade 1 splenic liposarcoma had a significantly greater MST (1,009 days), compared with dogs with grade 2 or 3 splenic liposarcoma (MST, 206 and 74 days, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Results confirmed that splenic liposarcoma is a rare differential diagnosis in dogs with a splenic mass. Survival time was influenced by preoperative clinical stage and histologic grade.

Racial/Ethnic Differences in Labor Outcomes with Prostaglandin Vaginal Inserts.

OBJECTIVE: The aim of this study is to compare labor outcomes across race/ethnicity in women undergoing prostaglandin labor induction. METHODS: Secondary analysis of misoprostol vaginal insert (MVI) trial, a double-blind, randomized, control trial of 1,308 patients comparing sustained release vaginal inserts containing dinoprostone 10 mg and misoprostol 50 mcg (MVI 50) or 100 mcg (MVI 100). RESULTS: Achievement of active labor and induction failures were similar across race/ethnicity. Cesareans were performed less frequently in whites (29 %) and Hispanics (24.5 %) compared to blacks (32.7 %) (adjusted odds ratio (aOR) 0.87, 95 % confidence interval (CI) 0.47-0.97, p = 0.03 and aOR 0.86, 95 % CI 0.44-0.97, p = 0.03, respectively). When compared to blacks, whites were less likely to undergo cesarean for non-reassuring fetal heart rate tracing (aOR 0.41, 95 % CI 0.25-0.66, p = 0.0003), as were Hispanics (aOR 0.38, 95 % CI 0.22-0.65, p = 0.0004). Postpartum hemorrhage occurred more frequently in Hispanics (8.8 %) versus blacks (4.1 %) and whites (OR 2.27, 95 % CI 0.23-0.82, p = 0.02 and OR 3.69, 95 % CI 0.14-0.51, p < 0.0001, respectively). Birth weights of black infants were lower than whites (p < 0.0001) and Hispanics (p = 0.0003). Neonatal outcomes did not differ between groups. CONCLUSION: Differences in labor induction outcomes with prostaglandin labor induction exist based on race/ethnicity. Blacks delivered smaller babies, were more likely to undergo cesarean, and have cesareans performed for non-reassuring fetal heart tracing compared to other groups. Hispanics were more likely to experience postpartum hemorrhage compared to the other races.

Appendicular osteosarcoma in small-breed dogs: 51 cases (1986-2011).

OBJECTIVE: To describe outcomes for small-breed dogs with appendicular osteosarcoma. DESIGN: Multi-institutional retrospective case series. ANIMALS: 51 small-breed dogs. PROCEDURES: Records from participating Veterinary Society of Surgical Oncology members were searched for dogs that weighed ≤ 15 kg (33 lb) with a histologic diagnosis of appendicular osteosarcoma. The Kaplan-Meier method was used to determine median survival times (MSTs), and Cox regression was performed to identify variables associated with survival time. RESULTS: Tumors were most commonly located on the humerus (n = 15) and femur (14). Of the 51 study dogs, 9 were treated nonsurgically, 16 underwent amputation of the affected limb only, and 26 underwent curative-intent treatment, with MSTs of 112, 257, and 415 days, respectively. The MST did not differ significantly between dogs in the amputation-only and curative-intent groups. For dogs in the nonsurgical group, MST decreased significantly as the tumor histologic score increased. For dogs in the amputation-only group, MST decreased as body weight increased. CONCLUSIONS AND CLINICAL RELEVANCE: For the small-breed dogs with appendicular osteosarcoma of the present study, tumor histologic grade and mitotic index were subjectively lower and MST following amputation of the affected limb without adjuvant chemotherapy was longer, compared with those for similarly affected larger dogs. Results indicated no significant advantage in MST for dogs that underwent curative-intent treatment versus dogs that underwent amputation only, and further investigation of the importance of adjuvant chemotherapy is warranted.

Misoprostol vaginal insert for induction of labor: a delivery system with accurate dosing and rapid discontinuation.

Labor induction and cervical ripening are widely utilized and new methods are constantly being investigated. Prostaglandins have been shown to be effective labor induction agents and, in particular, were compared with other prostaglandin preparations; vaginal misoprostol used off-label was associated with reduced failure to achieve vaginal delivery. The challenge is to provide this medication with the correct dosing for this indication and with the ability to discontinue the medication if needed, all while ensuring essential maternal and neonatal safety. The misoprostol vaginal insert initiates cervical ripening using a delivery system that controls misoprostol release and can be rapidly removed. This article reviews the development, safety and efficacy of the misoprostol vaginal insert for induction of labor and cervical ripening, and will focus on vaginally administered prostaglandins.

Detection and isolation of Influenza A virus subtype H1N1 from a small backyard swine herd in Colorado.

Influenza A virus subtype H1N1 A(H1N1)pdm09 was first confirmed in pigs in the United States in October 2009. In November 2010, lungs and intestines from 2 York piglets from a small, privately owned herd were submitted to the Colorado State University Veterinary Diagnostic Laboratory. The submitting veterinarian reported rapid weight loss and signs of pneumonia in the piglets. Gross lesions included caudoventral pneumonia in both piglets, and histologic lesions in the lungs showed characteristics consistent with influenza virus and bacterial infection. Ribonucleic acid extracted from fresh lung homogenates from both piglets was positive for influenza A(H1N1)pdm09 by a real-time reverse transcription polymerase chain reaction. Virus was isolated from lung homogenates from both piglets in Madin-Darby canine kidney cells, as well as in 10-day-old specific pathogen-free embryonated chicken eggs. Sequence analysis showed 98% homology with 2009 H1N1 human isolates from across the United States and 98% homology against two 2009 and 2010 swine isolates from Nebraska and Minnesota. The current report documents the possible transmission of pandemic influenza A(H1N1)2009 virus [A(H1N1)pdm09] from a human being to a small, privately owned backyard swine herd. The owner was employed as a pharmacist, making occupational exposure to the pandemic influenza A(H1N1)pdm09 a possibility.