Malignant transformation of an intraparenchymal hemangioma in the cervical spinal cord of a German shepherd dog.

An 8-year-old female spayed German shepherd dog was presented for evaluation of a 1-week history of right thoracic limb monoparesis. Magnetic resonance imaging (MRI) identified an intraparenchymal, T2 hypointense and T1 isointense, strongly heterogeneously contrast-enhancing mass with moderate internal susceptibility artifact on T2* images at the level of the cranial extent of the C5 vertebral body. Euthanasia was elected after a rapid neurologic decline in the 24 hours after MRI. Necropsy and histopathology identified an intraparenchymal hemangiosarcoma arising from a hemangioma in the cervical spinal cord, with no evidence of neoplastic disease in any other examined organs. The spectrum of vasoproliferative disorders in the central nervous system in veterinary species has been codified recently, but hemangiosarcoma is considered metastatic to the central nervous system. Herein we describe the clinical, imaging, and histologic findings in a dog with a novel primary location of hemangiosarcoma in the cervical spinal cord.

Circulating nucleosomes as a potential cancer biomarker in dogs with splenic nodular lesions.

Splenic nodular lesions in dogs can be either benign or malignant. They might be discovered incidentally or, in case of rupture, they may lead to hemoabdomen. Nevertheless, splenectomy followed by histopathology is essential for diagnosis and to prevent rupture. Yet, this invasive procedure might be postponed for dogs with benign splenic nodular lesions. Conversely, owners may opt for euthanasia over surgery for malignancies with poor prognosis like hemangiosarcoma. Thus, anticipating diagnosis with non-invasive biomarkers is crucial for proper patient management. In this prospective study, plasma samples were collected from 66 dogs with histologically confirmed splenic nodular lesions. A canine-specific ELISA kit was applied to assess nucleosome concentration, with histopathology of the spleen serving as the gold standard. Nucleosome concentration was found to be significantly higher in dogs with malignant splenic nodular lesions, particularly in those with hemangiosarcoma and other malignancies. The presence of hemoabdomen, more prevalent in dogs with splenic malignancy, also resulted in increased plasmatic nucleosome concentrations. Plasma nucleosomes could serve as a biomarker for detecting malignant splenic nodular lesions in dogs. More research is needed to understand how nucleosome concentration relate to disease stage and prognosis in dogs with hemangiosarcoma.

Ventricular cardiac hemangiosarcoma with brain metastases in a dog.

An 11-year-old, female, spayed, soft-coated Wheaten terrier presented for acute onset of neurological signs. On presentation, neurological examination showed right thoracic and pelvic limb proprioceptive deficits, absent right menace reflex, and weak right nasal septum response. A left thalamocortical lesion was localized. On thoracic auscultation, an arrhythmia was noted, and electrocardiography showed frequent ventricular premature complexes and rare runs of ventricular tachycardia. Echocardiography identified an interventricular septal mass extending into the lumen of the left ventricle. Thalamocortical metastasis secondary to the cardiac mass was suspected to be the cause of the patient's neurological signs. Humane euthanasia was elected by the owner due to the patients clinical status and poor prognosis. A postmortem examination diagnosed hemangiosarcoma of the interventricular septum, the right ventricular free wall, and left ventricular free wall. The left ventricle adjacent to the paraconal groove showed myocardial necrosis and inflammation. Metastases to the brain and secondary intracranial hemorrhage were found which were suspected to be the cause of the antemortem neurological signs. Concurrent pulmonary and hepatic metastases were noted. This report describes a rare presentation of an intracardiac hemangiosarcoma of the interventricular septum, right ventricle, and left ventricle in a patient presenting with neurological signs.

HEMANGIOSARCOMA IN RED WOLVES (CANIS RUFUS) AND GRAY WOLVES (CANIS LUPUS) IN HUMAN CARE: SIX CASES.

Wolves are commonly housed in zoological institutions and captive breeding facilities that are essential for maintaining genetic diversity and for the recovery of declining populations. Neoplasia is a common cause of mortality in wolves, but hemangiosarcoma has not previously been described. This condition was diagnosed in four red wolves (Canis rufus) and two gray wolves (Canis lupus) housed at five different institutions between 2008 and 2018. Animals were 11-16 yr of age at the time of presentation. Clinical signs included loss of body condition, abdominal distension, lethargy, weakness, ataxia, and hyporexia. Three animals were mildly anemic. All animals were humanely euthanized within an average of 3 d from onset of clinical signs. Two animals had primary splenic tumors, two had pelvic tumors with one originating from the aorta, and one had a cranial mediastinal mass. Diagnosis was made on postmortem histologic examination in all cases. Four wolves had evidence of metastases with foci in the lungs, lymph nodes, mesentery, liver, subcutis/skeletal muscle, kidney, adrenal, and thyroid gland. Hemangiosarcoma should be considered in geriatric wolves presenting with nonspecific signs, particularly if abdominal distension, free peritoneal fluid, or anemia is present.

Ultrasonographic liver nodules are more often benign lesions in dogs with hemoperitoneum secondary to splenic tumor rupture.

OBJECTIVE: To evaluate the reliability of preoperative abdominal ultrasonography as a staging tool for dogs with hemoperitoneum due to presumed splenic tumor rupture, focusing on the detection of metastatic lesions in the liver. ANIMALS: 99 dogs from 20 emergency and specialty hospitals across the US. METHODS: Dogs with nontraumatic hemoperitoneum secondary to splenic tumor rupture were included. A post hoc analysis was conducted on data from a nationwide prospective trial investigating novel treatments for canine hemangiosarcoma. The accuracy of preoperative staging was assessed by comparing ultrasonographic findings with intraoperative observations and histologic findings. RESULTS: On preoperative ultrasonography, there was a 20% incidence of liver lesions identified, with no association to liver lesions seen during operation. Notably, 22% of liver lesions observed during operation were missed on preoperative ultrasonography. The presence of liver lesions on preoperative ultrasonography was associated with a higher likelihood of a benign splenic tumor diagnosis. There was no association between the identification of liver lesions on preoperative ultrasonography and the presence of metastatic disease on liver biopsy, with a sensitivity and specificity of 19% and 82%, respectively. Additionally, ultrasound had low sensitivity in detecting intra-abdominal lesions beyond the liver and spleen, with 82% of these lesions missed preoperatively. CLINICAL RELEVANCE: This study challenges conventional perceptions around the approach to staging in dogs with hemoperitoneum. These findings advocate for a reevaluation of the staging approach, with more comprehensive modalities like whole-body CT or MRI potentially being more warranted.

Evaluating preoperative coagulation panels in dogs undergoing liver lobectomy for primary liver tumors: A multi-institutional retrospective study.

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.

Effects of chemotherapy treatment with doxorubicin on right ventricular function in dogs.

Left ventricular dysfunction in dogs after the administration of doxorubicin (DOX) has been extensively examined. However, the effects of DOX on right ventricular (RV) function remain unknown. Therefore, the present study investigated whether the chemotherapy treatment with DOX decreases RV function. Twelve dogs (five with multicentric lymphoma, four with hemangiosarcoma, two with thyroid cancer, and one with lung adenocarcinoma) that received at least two doses of DOX were prospectively enrolled. Echocardiography and the measurement of troponin I were performed prior to each administration of DOX and approximately one month after the last administration. Right ventricular function was assessed by the RV fractional area change and RV Tei index. Two (n=4), three (n=3), four (n=3), and five (n=2) doses of DOX were administered. While no significant differences were observed in the RV fractional area change, the RV Tei index was significantly impaired after two doses of DOX. Troponin I level significantly increased after four doses. Cumulative doses of DOX correlated with the RV Tei index (r=0.77, P<0.001). The present results demonstrated that the chemotherapy treatment with DOX decreased RV function in a dose-dependent manner in dogs.

Prospective study of successful autologous dendritic cell therapy in dogs with splenic stage II hemangiosarcoma.

Hemangiosarcoma is an aggressive tumour that most frequently occurs in larger, middle-aged dogs of certain breeds. The spleen is the most commonly affected organ. The aim of this prospective therapy study was to evaluate the clinical effect of autologous, monocyte-derived dendritic cell (DC) therapy in canine hemangiosarcoma stage II after splenectomy. Dogs (n=452) diagnosed with splenic hemangiosarcoma that underwent splenectomy were enrolled. Of these, 42 dogs with stage II entered the DC therapy study. The median survival time for the total group of 42 dogs was 203 days. The median survival for the group (n=34) that received the full DC therapy (≥3 vaccines) was 256 days, with a 29 % one-year survival rate and a hazard ratio of 0.30, adjusted to age and bodyweight (P=0.010). We further observed a significant increase in DC yield after each application and demonstrated that DC yield at the beginning of treatment is significantly related to patient survival. While further evidence is needed, we conclude that autologous, monocyte-derived DC therapy is a viable alternative to standard treatment methods of canine splenic stage II hemangiosarcoma.

Right-sided ureteral hemangiosarcoma in a paraplegic dog.

BACKGROUND: This study aims to describe a rare case of primary ureteral hemangiosarcoma, in which surgical intervention preserved the kidney and ureter after tumor removal. CASE PRESENTATION: A 13-year-old, neutered male dog, weighing 14 kg, mixed-breed, presented with apathy, anorexia, acute-onset vomiting, and abdominal discomfort during the physical examination. Ultrasonography and pyelography revealed a right-sided dilation of the renal pelvis and ureter due to complete obstruction in the middle third of the ureter. A mass obstructing the lumen of the right ureter was completely resected, and ureteral suturing was performed, preserving the integrity of the involved structures. Histopathology confirmed primary ureteral hemangiosarcoma. Due to the local and non-invasive nature of the mass, chemotherapy was not initiated. The patient's survival was approximately two years, and normal renal function was preserved throughout this period. CONCLUSIONS: Considering this type of tumor in the differential diagnosis of upper urinary tract obstructive disorders. Furthermore, the preservation of the ureter and kidney is a suitable therapeutic option after surgical resection of non-invasive tumors.

Prognostic value of tumour-related factors associated with canine retroperitoneal hemangiosarcoma in comparison with other anatomic presentations: A retrospective observational study.

BACKGROUND: Dogs with retroperitoneal hemangiosarcoma (HSA) exhibit variable postoperative median survival times (MST). OBJECTIVE: To retrospectively evaluate the prognostic value of selected tumour-related factors, such as tumour size, rupture, invasion into adjacent tissue, involvement of lymph node and distant metastasis, they were analysed in dogs with retroperitoneal HSA. METHODS: Ten dogs with retroperitoneal HSA managed solely with surgical excision were reviewed and compared with spleen (71) and liver (9) HSA. The Kaplan-Meier method and log-rank analysis were used compare MSTs between factors. Multivariable Cox proportional-hazard analysis was used to compare differences between arising sites. RESULTS: Retroperitoneal HSA showed comparatively longer postoperative MST compared with that of spleen and liver HSA and demonstrated significantly longer MST (p = 0.003) for tumours ≥5 cm (195 days) than <5 cm (70 days). Spleen HSA revealed significantly shorter MSTs in involvement of distant lymph nodes (23 days) and distant metastasis (39 days) than those in negative (83 days, p = 0.002 and 110 days, p < 0.001, respectively). Liver HSA also revealed significantly shorter MST (16.5 days compared with 98 days, p = 0.003) for distant metastasis. Additionally, hazard ratios (HRs) and their forest plot for overall HSA revealed as poor prognostic factors, arising sites (spleen; HR 2.78, p = 0.016 and liver; HR 3.62, p = 0.019), involvement of distant lymph nodes (HR 2.43, p = 0.014), and distant metastasis (HR 2.86, p < 0.001), and as better prognostic factor of tumour size ≥5 cm (HR 0.53, p = 0.037). CONCLUSION: In combination with overall HSA, retroperitoneal HSA shows comparatively longer postoperative MST compared to spleen and liver HSA, associated with tumour size ≥5 cm suggesting better prognostic factor.

Gadoxetate disodium (Gd-EOB-DTPA) contrast-enhanced magnetic resonance imaging for differentiation between benign and malignant splenic lesions in dogs.

Malignant splenic lesions in dogs are common, with hemangiosarcoma diagnosed most frequently, and there have been no consistent clinicopathologic, gross, or imaging characteristics identified that differentiate malignant from benign splenic lesions. Histopathology is required for definitive diagnosis, and given the poor long-term prognosis of malignant splenic lesions, a noninvasive tool to aid in diagnosis would be valuable. This prospective cohort study utilized gadoxetate disodium, a liver-specific contrast agent (Gd-EOB-DPTA; Eovist), to identify the general lesion and pre- and postcontrast signal characteristics of benign and malignant splenic and hepatic lesions in dogs with naturally occurring disease. Twenty-five dogs were enrolled, Eovist-enhanced MRI was performed, and dogs were taken to surgery for splenectomy and other organ biopsy. All histopathology and MRI studies were evaluated by a single pathologist and a single radiologist, respectively. The associations between the tumor type and numerous variables defined on MRI were evaluated using Fisher's exact tests, and the significance was identified at a P-value of .05. Malignant splenic masses were identified in 11/25 (44%) dogs, and 5/11 malignancies represented hemangiosarcoma. The presence of abdominal effusion (P = .017) and the presence of hepatic nodules on MRI (P = .009) were associated with splenic malignancy. There were no benign T2 hyperintense and no malignant T2 hypointense lesions (P = .021). Utilization of the T2 W MRI sequence may aid in the identification of malignant splenic lesions, particularly when accompanied by abdominal effusion and hepatic lesions.

Hemangiosarcoma Cells Promote Conserved Host-derived Hematopoietic Expansion.

Hemangiosarcoma and angiosarcoma are soft-tissue sarcomas of blood vessel-forming cells in dogs and humans, respectively. These vasoformative sarcomas are aggressive and highly metastatic, with disorganized, irregular blood-filled vascular spaces. Our objective was to define molecular programs which support the niche that enables progression of canine hemangiosarcoma and human angiosarcoma. Dog-in-mouse hemangiosarcoma xenografts recapitulated the vasoformative and highly angiogenic morphology and molecular characteristics of primary tumors. Blood vessels in the tumors were complex and disorganized, and they were lined by both donor and host cells. In a series of xenografts, we observed that the transplanted hemangiosarcoma cells created exuberant myeloid hyperplasia and gave rise to lymphoproliferative tumors of mouse origin. Our functional analyses indicate that hemangiosarcoma cells generate a microenvironment that supports expansion and differentiation of hematopoietic progenitor populations. Furthermore, gene expression profiling data revealed hemangiosarcoma cells expressed a repertoire of hematopoietic cytokines capable of regulating the surrounding stromal cells. We conclude that canine hemangiosarcomas, and possibly human angiosarcomas, maintain molecular properties that provide hematopoietic support and facilitate stromal reactions, suggesting their potential involvement in promoting the growth of hematopoietic tumors. SIGNIFICANCE: We demonstrate that hemangiosarcomas regulate molecular programs supporting hematopoietic expansion and differentiation, providing insights into their potential roles in creating a permissive stromal-immune environment for tumor progression.

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.

Imaging diagnosis: Disseminated hemangiosarcoma in a Welsh pony.

A 16-year-old pony gelding presented with epistaxis and a head tilt. Referral skull radiographs suggested an ethmoid hematoma. Concurrent neurologic abnormalities prompted contrast-enhanced CT of the head and cranial neck, revealing numerous hyperattenuating masses throughout the brain and paranasal sinuses, along with a large osteolytic mass in the second cervical vertebra. The vertebral mass extended into the vertebral canal, causing focal extradural compressive myelopathy. These findings were inconsistent with ethmoid hematoma and metastatic hemangiosarcoma or malignant melanoma were prioritized as potential causes for the clinical signs. Postmortem examination confirmed the sinonasal, intracranial, and vertebral masses as hemangiosarcoma, and additionally revealed innumerable thoracoabdominal metastatic lesions and hemorrhagic foci. A final diagnosis of disseminated hemangiosarcoma was made. In this study, CT proved invaluable for evaluating the severity and characterizing regional disease and neural involvement, directly affecting case management decisions.

Ultrasonographic and CT-scan findings of splenic active chylous effusion and postlymphangiography enhancement in a cat with chylothorax associated with splenic angiosarcoma.

A 12-year-old domestic shorthair cat was presented with relapsing noncardiogenic chylothorax. CT-lymphangiography of the thorax confirmed bilateral pleural effusion without evidence of an underlying intra-thoracic origin. Abdominal CT-lymphangiography revealed a 2.6 cm diameter splenic mass surrounded by chylous effusion actively collecting during ultrasonographic assessment. Following splenectomy, histopathological analysis revealed that the splenic mass exhibited characteristics indicative of splenic angiosarcoma. This case report highlights the utility of advanced thoracic and abdominal imaging, notably CT-lymphangiography, in the diagnostic evaluation of chylothorax in cats. The identification of a splenic mass encased in chylous effusion should prompt a proactive case management strategy.

Pathological findings of mammary gland carcinoma and hemangiosarcoma cases in two African wild dogs (Lycaon pictus).

There are few studies on diseases affecting endangered African wild dogs. We report our findings on malignant tumors in two African wild dogs. Case 1 was a 6-year-old intact female diagnosed with inflammatory mammary carcinoma with pulmonary metastasis. Case 2 was an 11-year-old male diagnosed with primary hemangiosarcoma of the left atrial coronary sulcus with metastasis to multiple organs. Additionally, the tumor had grown through the cardiac wall, causing cardiac tamponade. The identification of disease incidence trends provides important information which will allow for the early detection and treatment of malignant tumors, and aid in the conservation of this species.

Improved predictability is needed for calculators used to preoperatively determine the etiology of splenic masses in dogs: an external validation study of the HeLP score and T-STAT.

OBJECTIVE: To assess the predictability of the hemangiosarcoma likelihood prediction (HeLP) score and the Tufts Splenic Tumor Assessment Tool (T-STAT) for hemangiosarcoma and malignancy, respectively. ANIMALS: 261 dogs undergoing splenectomy for a splenic mass. METHODS: Medical records were retrospectively reviewed; variables for the HeLP score and T-STAT were collected, and scores were assigned. Area under the curve (AUC) was calculated for each score. RESULTS: The HeLP score included 141 dogs; hemangiosarcoma was diagnosed in 87 (61.7%) dogs. The median cumulative HeLP score was 51 (range, 17 to 82; IQR, 39 to 58) for dogs with hemangiosarcoma and 28 (range, 0 to 70; IQR, 17 to 41) for dogs without hemangiosarcoma. The categorical HeLP score was low (28; 32.2%), medium (31; 35.6%), and high (28; 32.2%) for dogs with hemangiosarcoma and was low (41; 75.9%), medium (9; 16.7%), and high (4; 7.4%) for dogs without hemangiosarcoma. The AUC of the cumulative and categorical HeLP scores for diagnosis of hemangiosarcoma were 0.79 (95% CI, 0.71 to 0.86) and 0.73 (95% CI, 0.65 to 0.82), respectively. The T-STAT included 181 dogs. Lesions were benign in 95 (52.5%) and malignant in 86 (47.5%) dogs. The median T-STAT score was 62% (range, 5% to 98%; IQR, 36% to 77%) for dogs with malignant lesions and 38% (range, 5% to 91%; IQR, 24% to 59%) for dogs with benign lesions. The T-STAT had an AUC of 0.68 (0.60 to 0.76) for diagnosis of malignancy. CLINICAL RELEVANCE: The HeLP score had acceptable performance, and the T-STAT had poor performance for diagnosis prediction. A tool with excellent or outstanding discrimination is needed to more reliably predict the presence of hemangiosarcoma or a malignant lesion preoperatively.

Obstructive cardiac myxosarcoma of the right ventricular outflow tract with pulmonary embolism and concurrent right atrial hemangiosarcoma in a dog.

A 13-year-old spayed female rottweiler crossbreed dog was presented with an 8-day history of abnormal gait and collapse associated with excitement or physical activity. A cardiac gallop was noticed on thoracic auscultation, and a 1st-degree atrioventricular block and sinus tachycardia were noted on an electrocardiogram. Echocardiography identified a hypoechoic, irregularly marginated luminal mass in the right ventricle at the level of the pulmonic valves. Postmortem gross examination confirmed the presence of a soft, polypoid, and botryoid mass (9 × 3 × 3 cm) with a smooth and glistening surface attached to the endocardium of the right ventricular outflow tract and extending to the pulmonary artery. The histological findings were consistent with the diagnosis of myxosarcoma with pulmonary embolism. In addition, the dog in this report had a right atrial hemangiosarcoma and a cutaneous hemangioma unrelated to her clinical findings. Key clinical message: Cardiac myxosarcomas are very rare neoplasms in dogs and concomitant primary heart tumors of different histogenesis are even rarer in dogs. To the authors' knowledge, this is the first report of coexistent myxosarcoma and hemangiosarcoma in the heart of a dog. Cardiac myxosarcomas should be considered in the differential diagnosis of intracavitary heart masses associated with signs of cardiac obstruction and failure.

Myxosarcome cardiaque obstructif de la voie d'éjection du ventricule droit avec embolie pulmonaire et hémangiosarcome auriculaire droit concomitant chez un chien. Une chienne croisée rottweiler stérilisée âgée de 13 ans a été présentée avec une histoire de démarche anormale et d'effondrement associés à l'excitation ou à l'activité physique depuis 8 jours. Un galop cardiaque a été noté à l'auscultation thoracique, un bloc auriculo-ventriculaire du 1er degré et une tachycardie sinusale ont été notés à l'électrocardiogramme. L'échocardiographie a permis d'identifier une masse luminale hypoéchogène et irrégulièrement marginalisée dans le ventricule droit au niveau des valvules pulmonaires. L'examen macroscopique post-mortem a confirmé la présence d'une masse molle, polypoïde et botryoïde (9 × 3 × 3 cm) avec une surface lisse et brillante attachée à l'endocarde de la voie d'éjection du ventricule droit et s'étendant jusqu'à l'artère pulmonaire. Les résultats histologiques concordaient avec le diagnostic de myxosarcome avec embolie pulmonaire. De plus, la chienne dans ce rapport présentait un hémangiosarcome auriculaire droit et un hémangiome cutané sans rapport avec ses résultats cliniques.Message clinique clé :Les myxosarcomes cardiaques sont des néoplasmes très rares chez le chien et les tumeurs cardiaques primaires concomitantes d'histogenèse différente sont encore plus rares chez le chien. À la connaissance des auteurs, il s'agit du premier rapport de myxosarcome et d'hémangiosarcome coexistant dans le cœur d'un chien. Les myxosarcomes cardiaques doivent être pris en compte dans le diagnostic différentiel des masses cardiaques intracavitaires associées à des signes d'obstruction et d'insuffisance cardiaque.(Traduit par Dr Serge Messier).

Atypically located accessory splenic hemangiosarcoma in a Dog: Diagnostic value of triple-phase computed tomography.

A 10-year-old Cocker spaniel presented with lethargy. Triple-phase computed tomography was obtained with a contrast test bolus at the level of porta hepatis, which revealed a right lower abdominal mass. The mass was not connected to other abdominal organs; however, a linear structure was observed connecting the splenic hilum to the mass, which was suspected to be the feeding vessel. The arterial phase image was obtained again with a contrast bolus at the level of the celiac artery. A prominent contrast-enhanced feeding artery originating from the splenic artery to the mass was observed. Histopathology confirmed an accessory splenic hemangiosarcoma.

Telangiectatic osteosarcoma in four dogs: Cytologic, histopathologic, cytochemical, and immunohistochemical findings.

Telangiectatic osteosarcoma is a rare variant of osteosarcoma histologically and clinically similar to hemangiosarcoma (HSA). This case series describes the imaging and cytologic features of four histologically confirmed telangiectatic osteosarcomas, including the use of cytochemical stains. Alkaline phosphatase (ALP) was applied to Wright-Giemsa-stained cytology slides, and Factor VIII immunohistochemistry was evaluated. Cytologic characteristics included atypical mesenchymal cells with evidence of acute and chronic hemorrhage. Telangiectatic osteosarcoma cases had positive ALP cytochemical staining, while control HSA cases were negative. Factor VIII immunohistochemistry was negative in telangiectatic osteosarcoma and positive in HSA. Cytologic diagnosis of telangiectatic osteosarcoma with positive ALP cytochemical staining can help differentiate this neoplasm from HSA.