Sensitivity, specificity, and interobserver variability of survey thoracic radiography for the detection of heart base masses in dogs

Computed tomographic findings in canine and feline heart base tumors (25 cases)

Tumors located at the heart base are rare in dogs and cats and aortic body tumors (chemodectoma/paraganglioma), hemangiosarcoma, ectopic thyroid carcinoma, lymphoma, and other uncommon neoplasia can be found at that location. The objective of this retrospective case series was to describe the CT characteristics of canine and feline heart base tumors. CT studies of 21 dogs and four cats with histologically or cytologically confirmed heart base tumors were reviewed for size, location, shape, margination, contrast enhancement, adjacent neovascularization, invasion, mass effect, cavitary effusions, and metastasis. Neuroendocrine tumors (15 aortic body tumors, three ectopic thyroid carcinoma, and three nonspecific neuroendocrine) were more commonly observed than hemangiosarcoma (4) and were frequently located between the cranial vena cava and aortic arch (12/21; 57%) and or dorsal to the pulmonary trunk bifurcation/pulmonary arteries (10/21; 48%). Hemangiosarcoma was more commonly found cranioventral to the aortic arch and cranial to the right auricular appendage (3/4; 75%). Mediastinal and peritumoral neovascularization was associated with 16/21 (76%) neuroendocrine tumors but none of the hemangiosarcoma. Median postcontrast attenuation in Hounsfield units (HU) was higher in neuroendocrine (110 HU) than in hemangiosarcoma (51 HU). Pericardial effusion was frequently observed with hemangiosarcoma (3/4; 75%) and infrequently in neuroendocrine (3/21; 14%). In four cases (all neuroendocrine), concurrent cranial mediastinal masses were present. CT provides useful information regarding the characteristics of heart base tumors, indicating differences between the appearance of neuroendocrine tumors and hemangiosarcoma. However, no differences were found between aortic body tumors and ectopic thyroid carcinoma.

Ultrasound-Guided Radiofrequency Ablation of Chemodectomas in Five Dogs

Chemodectomas are low prevalence tumors with complex clinical management. Many present as an incidental finding however, in other dogs, they produce pericardial effusion and/or compression, leading to the appearance of severe clinical signs. There are currently several approaches: surgery, radiotherapy, stent placement and chemotherapy. This is the first description of percutaneous echo-guided radiofrequency ablation of aortic body tumors. This minimally invasive treatment is based on high frequency alternating electrical currents from an electrode that produces ionic agitation and generates frictional heat, causing coagulation necrosis. Five dogs with an echocardiographic and cytological diagnosis of chemodectoma underwent percutaneous echo-guided radiofrequency ablation. At the time of presentation, all the dogs showed clinical signs, such as ascites and/or collapse. There were no complications either during the procedure or in the following 24 hours. Rapid clinical improvement associated with a reduction in size and change in sonographic appearance of the mass were achieved with no complications. Six months follow-up was carried out in all dogs. A second percutaneous echo-guided RFA was performed eight months after the first procedure in one dog. Based on our experience, radiofrequency ablation seems to be a feasible and safe technique, making it a potential alternative therapeutic approach in the clinical management of aortic body tumors leading to severe clinical compromise.

Horizons in Veterinary Precision Oncology: Fundamentals of Cancer Genomics and Applications of Liquid Biopsy for the Detection, Characterization, and Management of Cancer in Dogs

Cancer is the leading cause of death in dogs, in part because many cases are identified at an advanced stage when clinical signs have developed, and prognosis is poor. Increased understanding of cancer as a disease of the genome has led to the introduction of liquid biopsy testing, allowing for detection of genomic alterations in cell-free DNA fragments in blood to facilitate earlier detection, characterization, and management of cancer through non-invasive means. Recent discoveries in the areas of genomics and oncology have provided a deeper understanding of the molecular origins and evolution of cancer, and of the "one health" similarities between humans and dogs that underlie the field of comparative oncology. These discoveries, combined with technological advances in DNA profiling, are shifting the paradigm for cancer diagnosis toward earlier detection with the goal of improving outcomes. Liquid biopsy testing has already revolutionized the way cancer is managed in human medicine - and it is poised to make a similar impact in veterinary medicine. Multiple clinical use cases for liquid biopsy are emerging, including screening, aid in diagnosis, targeted treatment selection, treatment response monitoring, minimal residual disease detection, and recurrence monitoring. This review article highlights key scientific advances in genomics and their relevance for veterinary oncology, with the goal of providing a foundational introduction to this important topic for veterinarians. As these technologies migrate from human medicine into veterinary medicine, improved awareness and understanding will facilitate their rapid adoption, for the benefit of veterinary patients.

A retrospective analysis of stereotactic body radiation therapy for canine heart base tumors: 26 cases

INTRODUCTION

This study retrospectively evaluated outcomes and adverse radiation effects (AREs) associated with stereotactic body radiation therapy (SBRT) for canine heart base tumors (HBTs). A secondary aim was to identify any demographic or echocardiographic factors that might determine which dogs would most benefit from SBRT.

ANIMALS

Twenty-six dogs that received SBRT for an imaging-based diagnosis of a HBT were evaluated.

METHODS

Twenty-three dogs were treated with three fractions of 10 Gy delivered daily or every other day. The remaining 3 dogs received variable protocols of one to five fractions. Demographic, echocardiographic, and radiographic information, AREs, and treatment responses were collected. Correlations of these data with survival time were evaluated.

RESULTS

The median overall survival time was 404 days (95% confidence interval: 239-554 days). The majority of dogs experienced a partial response (25%) or stable disease (60%) for a median duration of 333 days (95% confidence interval: 94-526 days). Three dogs had progressive disease within six months of SBRT. Radiographic pneumonitis was identified in 7 of 23 dogs, and clinical pneumonitis was identified in 4 dogs. No other AREs were noted. The rate of distant metastasis was 13%. On multivariate analysis, it was found that vena caval obstruction, supraventricular and ventricular arrhythmias, clinical signs, and enlarged locoregional lymph nodes at presentation were negatively associated with survival time.

CONCLUSIONS

Stereotactic body radiation therapy was delivered with a low rate and degree of normal tissue complications. Asymptomatic dogs with confirmed, progressive growth of a HBT may most likely benefit from SBRT.

Correlação entre os achados radiográficos e ecocardiográficos sugestivos de aumento cardíaco em cães: 104 casos

RESUMO Radiografias torácicas e ecocardiogramas de 104 caninos foram avaliados e correlacionados quanto ao aumento das câmaras cardíacas. Os achados radiográficos foram correlacionados estatisticamente a fim de se estabelecer a acurácia do exame radiográfico na detecção do aumento cardíaco em comparação ao ecocardiográfico - padrão-ouro não invasivo. A correlação entre os achados radiográficos indicativos de aumento cardíaco e os índices ecocardiográficos mostrou-se fraca, significativa somente para VHS versus relação átrio esquerdo/aorta (r=0,3136), eixo curto versus relação átrio esquerdo/aorta (r=0,3813) e eixo curto versus velocidade da onda E (r=0,2021). A acurácia da radiografia na determinação subjetiva de aumento das câmaras cardíacas foi razoável, variando entre 72,1% e 80,8%. Em contrapartida, o VHS apresentou baixa acurácia (50,9%) na detecção de cardiomegalia.

PCR evaluation of selected vector-borne pathogens in dogs with pericardial effusion

OBJECTIVES

To investigate evidence for selected vector-borne pathogen infections in dogs with pericardial effusion living in a Mediterranean area in which several canine vector-borne diseases are endemic.

MATERIALS AND METHODS

Archived EDTA blood (n=68) and pericardial fluid samples (n=58) from dogs with pericardial effusion (n=68) were included. Dogs without pericardial effusion examined for other reasons were included as controls (n=60). Pericardial effusion was classified as neoplastic in 40 dogs, idiopathic in 23 dogs and of unknown aetiology in 5 dogs. Real-time PCR was performed for Leishmania infantum, Ehrlichia/Anaplasma species, Hepatozoon canis, Babesia species, Rickettsia species and Bartonella species, and sequencing of PCR products from positive samples was used to confirm species specificity.

RESULTS

Vector-borne pathogens were found in 18 dogs: 16 of 68 dogs with pericardial effusion (23·5%) and two of 60 control dogs (3·3%). Positive dogs demonstrated DNA of Leishmania infantum (n=7), Anaplasma platys (n=2, one dog coinfected with Leishmania infantum), Babesia canis (n=5), Babesia gibsoni (n=3) and Hepatozoon canis (n=2). Vector-borne pathogens were more commonly detected among dogs with pericardial effusion than controls (P=0·001). There was no relationship between aetiology of the pericardial effusion and evidence of vector-borne pathogens (P=0·932).

CLINICAL SIGNIFICANCE

Vector-borne pathogens are often detected in dogs with pericardial effusion and require further investigation, especially in dogs with idiopathic pericardial effusion. PCR can provide additional information about the potential role of vector-borne pathogens in dogs with pericardial effusion living in endemic areas.