Novel presentation of a feline patient with visceral and cervical lymph node hemangiosarcoma

OBJECTIVE

To report a novel presentation of feline hemangiosarcoma.

ANIMALS

A 14-year-old spayed female feline patient diagnosed with hemangiosarcoma of the spleen and a cervical lymph node.

CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES

The patient presented to the emergency service following a 1-week history of lethargy and hiding. Abdominal ultrasound revealed splenomegaly with multiple nodules and peritoneal fluid that was consistent with hemorrhagic effusion.

TREATMENT AND OUTCOME

The patient underwent a routine splenectomy and was started on doxorubicin. Histopathologic evaluation of the spleen confirmed visceral hemangiosarcoma. When the disease showed signs of progression, combination chemotherapy with cyclophosphamide and vincristine was initiated. Four months following presentation, a submandibular lymph node was removed and found to have metastatic hemangiosarcoma. From presentation to euthanasia, the patient survived 205 days.

CLINICAL RELEVANCE

Hemangiosarcoma is a rare cancer in feline patients, with a lack of veterinary literature on its presentation and chemotherapy protocols. The subject of this case report had a novel presentation of hemangiosarcoma and responded favorably to a chemotherapy protocol not previously described for this disease.

Natural Polymer-Based Nanogel for pH-Responsive Delivery of Sorafenib Tosylate in Hemangiosarcoma

Smart nanomedicinal treatment for cancer manifests a solubility challenge with inherent nanoscale size and nonspecific release with stimuli-responsive potential. This is the limelight in novel chemotherapy to pursue physiochemical differences between the tumor microenvironment (TME) and normal cells, which introduces active groups of nanocarriers responding to various stimuli, endowing them with concise responses to various tumor-related signals. The nanogels were successfully prepared by a modified solvent evaporation technique. Nine batches were formulated by changing the chitosan concentration (12, 14, 16 mg/ml) and sonication time (5, 10, 15 min). The formulations were optimized for particle size and zeta potential with high percent entrapment efficiency (%EE) through Central Composite Design software. The optimized batch F7 had a 182-nm size and high zeta potential (64.5 mV) with 98% EE. The drug release of F7 was higher at pH 6 (97.556%) than at pH 7.4 (45.113%). The pharmacokinetic study shows that the release follows the Hixon plot model (R2 = 0.9334) that shifts to zero order (R2 = 0.9149). The nanogel F7 was observed for stability and showed an absence of color change, phase separation, and opacity for 6 months. In the present study, the pH difference between cancer cells and normal cells is the key point of the smart nanogel. This study is promising but challenging depending on the in vivo study. The nanogel was successfully prepared and evaluated for pH-responsive release. As hemangiosarcoma commonly occurs in dogs, this formulation helps to limit the difficulties with administration.

Pathological Characterization and Risk Factors of Splenic Nodular Lesions in Dogs (Canis lupus familiaris)

In dogs, the spleen is a secondary lymphoid organ that can be affected by both neoplastic and non-neoplastic nodules. In general, few studies relate histopathological diagnosis to tumor size and the number of nodules in spleen biopsies. Some of these studies are inconclusive regarding the difference between neoplastic and non-neoplastic lesions and have small sample sizes or do not consider all splenic lesions. This study aimed to characterize splenic masses and determine risk factors for spleen tumors in dogs. A total of 507 histological reports corresponding to the diagnosis of splenic lesions in dogs from a private laboratory of animal pathology in the Metropolitan Region, Chile, were used. Data were analyzed by descriptive statistics and multiple logistic regression. The most frequent neoplastic and non-neoplastic diagnoses were hemangiosarcoma and hyperplasia, respectively. Most of the cases occurred in male (265 cases, 52.3%), senior (421 cases, 83%), and purebred individuals (342 cases, 67.5%). The most affected breeds were the Cocker Spaniel, German Shepherd, and Labrador Retriever. The most frequent lesion was a single nodule. The variables that exhibited a greater risk for the presentation of splenic neoplasia were male sex (odds ratio (OR) = 16.21; 95% confidence interval (CI) 1.741-150.879; p = 0.014), the presence of two or more splenic nodules (OR = 3.94; 95% CI 2.168-7.177; p < 0.001), an increase in nodule size greater than 2 cm (OR for quartiles 2, 3 and 4 of 2.2; 95% CI 1.036-4.941; p = 0.041, 2.9; 95% CI 1.331-6.576; p = 0.008, and 3.6; 95% CI 1.562-8.499; p = 0.003, respectively), and increasing age (OR = 1.23; 95% CI 1.048-1.436; p = 0.011). On the other hand, males exhibited a lower risk as age increases (OR = 0.76; 95% CI 0.615-0.928; p = 0.008). In conclusion, this study identified that males, multinodular presentation, nodule size, and age are risk factors for the occurrence of splenic neoplasia in dogs, knowledge that will contribute to the diagnostic management of dogs with spleen lesions.

A case of primary pulmonary angiosarcoma arising from tuberculous scar with fatal capillary bleeding

The etiology of primary pulmonary angiosarcoma is still unknown. Here we report a case of primary pulmonary angiosarcoma originated from a tuberculous scar and presented as aggressive deterioration with uncontrolled bleeding from capillaries with angiodysplasia.

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.

Prognostic impact of Ki-67 in canine splenic hemangiosarcoma: A preliminary study

Canine splenic hemangiosarcoma has a high metastatic rate and short survival time. Currently, the main prognostic parameters are tumor stage and therapy, while data on histologic parameters, such as grade and Ki-67 expression, are scarce. The aims of this study were to compare two methods of assessment of Ki-67, verify their prognostic impact, and define a threshold value based on survival. Thirty-one cases of histologically diagnosed canine splenic hemangiosarcoma, which were treated with splenectomy and had full staging and follow-up information, were collected. Three were stage I, 17 stage II, and 11 stage III. The mean mitotic count (MC) was 23.9 (standard deviation [SD]: 22.1) and the median was 15 (range, 1-93). Immunohistochemistry for Ki-67 was performed, the Ki-67 labeling index (Ki-67LI) was assessed as a percentage of positive neoplastic nuclei per ≥500 cell, and the Ki-67 count (KI-67C) was defined as the average number of positive nuclei using a 1 cm2 optical grid performed in 5, 40× fields. The mean Ki-67LI and Ki-67C were 56.4% (SD: 38.7) and 27.2 (SD: 12.9) and medians were 51% (range, 8.2-55.2) and 26 (range, 5.5-148), respectively. Using a cut-off of 56% and 9, respectively, Kaplan-Meier survival curves showed an association of overall survival with Ki-67LI and MC. In addition to clinical stage, Ki-67LI maintained its prognostic value on multivariate analysis, supporting the role of Ki-67LI as an independent prognostic parameter. Based on these results, we propose a diagnostically applicable cut-off value of 56% for Ki-67LI as a prognostic parameter for canine splenic hemangiosarcoma.

Immunohistochemical evidence of NF-kB activation in canine lymphomas, histiocytic sarcomas, hemangiosarcomas, and mast cell tumors

Increased or constitutive activation of nuclear factor kappa B (NF-kB) is a feature of many chronic disease processes, including cancer. While NF-kB overactivation has been documented extensively in human oncology, there is a relative paucity of data documenting the same phenomenon in veterinary medicine. To assess NF-kB activity, antibodies to p65 and p100/p52, which are components of NF-kB heterodimers, were first validated for specificity and canine cross-reactivity via Western blot and labeling of immortalized cell pellets. Then, nuclear labeling for these antibodies was assessed via QuPath software in over 200 tumor tissue samples (10 hemangiosarcomas, 94 histiocytic sarcomas, 71 lymphomas, and 28 mast cell tumors) and compared to immunolabeling in appropriate normal tissue counterparts. Greater than 70% of spontaneous canine tumors evaluated in this study had more nuclear p65 and p100/p52 immunoreactivity than was observed in comparable normal cell populations. Specifically, 144/204 (70.58%) of tumors evaluated had positive p65 nuclear labeling and 179/195 (91.79%) had positive p100/p52 nuclear labeling. Surprisingly, greater nuclear p100/p52 reactivity was associated with a longer progression-free survival (PFS) and overall survival (OS) in canine lymphomas. These results provide support and preliminary data to investigate the role of NF-kB signaling in different types of canine cancer.

Hemangiosarcoma in dogs as a potential non-rodent animal model for drug discovery research of angiosarcoma in humans

Since the domestication of dogs 10,000 years ago, they have shared their living environment with humans and have co-evolved. The breeding process that dogs have undergone in only a few centuries has led to a significant accumulation of specific genetic alterations that could induce particular diseases in certain breeds. These canine diseases are similar to what is found in humans with several differences; therefore, comparing such diseases occurring in humans and dogs can help discover novel disease mechanisms, pathways, and causal genetic factors. Human angiosarcoma (AS) and canine hemangiosarcoma (HSA), which are sarcomas originating from endothelium, are examples of diseases shared between humans and dogs. They exhibit similar characteristics and clinical behaviors, although with some critical differences resulting from evolution. In this review, we will describe the similarities and differences in terms of clinical and molecular characteristics between human AS and canine HSA, and discuss how these similarities and differences can be applied to advance the treatment of these diseases.

Efficacy and toxicity of carboplatin in the treatment of macroscopic mesenchymal neoplasia in dogs

Palliative chemotherapy options for dogs with macroscopic non-osseous mesenchymal tumours are limited. The purpose of this study was to assess the response rate of these tumours to carboplatin chemotherapy. Medical records of 28 dogs treated with carboplatin for macroscopic mesenchymal neoplasia between 1990 and 2022 were retrospectively reviewed. Sixteen dogs with soft tissue sarcoma and 12 dogs with haemangiosarcoma were included. Responses observed included one complete response and three partial responses, for an overall response rate of 14.2% (4/28) and median time to progression of 42 days (range 21-259 days). Responses were only seen in patients with haemangiosarcoma, for a response rate of 33.3% (4/12) and median time to progression for responders of 103 days (range 39-252 days). Median time to progression for dogs with metastatic disease was similar to those with only local disease (distant median: 44 days; local median: 23 days, p = 0.56). Dogs with chemotherapy-naïve disease were compared to dogs having received previous chemotherapy treatment and had a median time to progression of 75 days and 40.5 days respectively (p = 0.13). Twenty-two dogs experienced 48 adverse events, with most being grade 1 or 2 (79%). Carboplatin was well tolerated, with variable macroscopic anti-tumour activity and short response duration. Carboplatin may be an acceptable rescue option for dogs with macroscopic haemangiosarcoma, especially those patients that cannot receive doxorubicin.

Identification of genomic alterations with clinical impact in canine splenic hemangiosarcoma

Canine hemangiosarcoma (HSA) is an aggressive cancer of endothelial cells with short survival times. Understanding the genomic landscape of HSA may aid in developing therapeutic strategies for dogs and may also inform therapies for the rare and aggressive human cancer angiosarcoma. The objectives of this study were to build a framework for leveraging real-world genomic and clinical data that could provide the foundation for precision medicine in veterinary oncology, and to determine the relationships between genomic and clinical features in canine splenic HSA. One hundred and nine dogs with primary splenic HSA treated by splenectomy that had tumour sequencing via the FidoCure® Precision Medicine Platform targeted sequencing panel were enrolled. Patient signalment, weight, metastasis at diagnosis and overall survival time were retrospectively evaluated. The incidence of genomic alterations in individual genes and their relationship to patient variables including outcome were assessed. Somatic mutations in TP53 (n = 44), NRAS (n = 20) and PIK3CA (n = 19) were most common. Survival was associated with presence of metastases at diagnosis and germline variants in SETD2 and NOTCH1. Age at diagnosis was associated with somatic NRAS mutations and breed. TP53 and PIK3CA somatic mutations were found in larger dogs, while germline SETD2 variants were found in smaller dogs. We identified both somatic mutations and germline variants associated with clinical variables including age, breed and overall survival. These genetic changes may be useful prognostic factors and provide insight into the genomic landscape of hemangiosarcoma.

Clinical features and prognosis of retroperitoneal hemangiosarcoma in dogs with surgical resection with or without adjuvant doxorubicin

Retroperitoneal hemangiosarcoma (RPHSA) is a rare tumor in dogs with a poorly understood prognosis after surgery. The objectives of this study were to investigate the clinical features and prognosis of canine RPHSA that had undergone surgical resection. In this single-center, retrospective cohort study, we reviewed the medical records of dogs that had undergone surgical resection for retroperitoneal tumors and received a histopathologic diagnosis of HSA between 2005 and 2021. The median progression-free survival (PFS) and overall survival (OS) were 77.5 days and 168 days, respectively. In the present study, canine RPHSA had an aggressive biological behavior similar to visceral HSA. Further studies in larger canine populations are needed to evaluate the efficacy of adjuvant chemotherapy.

Prevalence of malignancy and factors affecting outcome of cats undergoing splenectomy

OBJECTIVE

To determine the prevalence of splenic malignancy in cats undergoing splenectomy and to investigate possible factors associated with post-operative outcome.

ANIMALS

62 client-owned cats that underwent splenectomy.

METHODS

Medical records of 4 UK-based referral hospitals were searched and data reviewed retrospectively over 17 years. Factors associated with outcomes post-splenectomy were analyzed.

RESULTS

50 out of 62 cats (81%) were diagnosed with splenic neoplasia. Mast cell tumor ([MCT], 42%), hemangiosarcoma ([HSA], 40%), lymphoma and histiocytic sarcoma (6% each) were the most common tumor types. Fifteen cats (24%) presented with spontaneous hemoabdomen and were all diagnosed with splenic neoplasia. The diagnostic accuracy of cytology to detect splenic malignant lesions was 73% (100% for MCTs and 54% for mesenchymal tumors). Median survival time for cats with nonneoplastic splenic lesions was 715 days (IQR, 18 to 1,368) and 136 days for cats with splenic neoplasia (IQR, 35 to 348); median survival time was longer for cats with splenic MCT when compared to cats with HSA (348 vs 94 days; P < .001). Presence of metastatic disease and anemia (PCV < 24%) at diagnosis were associated with a poorer survival when considering all cats. Presence of anemia, a splenic mass on imaging or spontaneous hemoabdomen were associated with a diagnosis of HSA (P < .001).

CLINICAL RELEVANCE

Benign splenic lesions were uncommon in this cohort of cats. Spontaneous hemoabdomen should prompt the clinician to suspect neoplasia in cats with splenic disease. Anemia and evidence of metastasis at diagnosis were poor prognostic factors regardless of the final diagnosis.

Intensity-modulated radiotherapy and chemotherapy for canine right atrial tumors: A retrospective study of seven dogs

Most primary cardiac tumors in dogs are located in the right atrium/atrial appendage, with hemangiosarcoma being the most common. The aims of this retrospective, case series were to describe outcomes for seven dogs with right atrial tumors treated with hypofractionated intensity-modulated radiotherapy and concurrent vinblastine and propranolol. One dog had a complete response, four dogs had partial responses and two dogs had stable disease after treatment. Effusions resolved in all dogs. Median progression-free survival was 290 days. Five dogs died from metastatic disease, one dog from unrelated neoplasia, and one dog is alive. Median overall survival was 326 days. Three dogs with confirmed hemangiosarcoma survived 244, 326, and 445 days. Two dogs developed clinically significant, but nonfatal, cardiac arrhythmias. One dog that received three courses of radiation had subclinical myocardial and arterial fibrosis at necropsy. Hypofractionated chemoradiotherapy was well tolerated and may provide clinical benefit in dogs with right atrial tumors.

LINE-1 Methylation Status in Canine Splenic Hemangiosarcoma Tissue and Cell-Free DNA

Splenic hemangiosarcoma is one of the most common malignant tumors in dogs, and early diagnosis is of great importance for achieving a good prognosis. DNA methylation plays an important role in cancer development. Long interspersed nuclear element 1 (LINE-1) is the most abundant repetitive element in the genome. LINE-1 hypomethylation has been shown to be related to carcinogenesis in humans, and it has been used as a novel cancer biomarker. This study aimed to evaluate the methylation status of LINE-1 in tumor tissue and circulating cell-free DNA and assess its clinical significance in canine splenic hemangiosarcoma. Genomic DNA was isolated from splenic masses of 13 dogs with hemangiosarcoma, 11 with other malignant tumors, and 15 with benign lesions. LINE-1 methylation was quantified using methylation-sensitive and -insensitive restriction enzyme digestion followed by real-time polymerase chain reaction. Additionally, blood samples were collected from eight patients to isolate cell-free DNA to determine LINE-1 methylation status changes during the treatment course. LINE-1 methylation in tumor samples was significantly lower in patients with hemangiosarcoma than in those with other malignant tumors and benign lesions. Non-significant but similar results were observed for the cell-free DNA samples. Our results demonstrate that LINE-1 methylation status is a potential biomarker for splenic hemangiosarcoma.

A prospective evaluation of the prevalence of thromboemboli and associated hemostatic dysfunction in dogs with carcinoma or sarcoma

BACKGROUND

Knowledge of the prevalence of thromboemboli and the associated hemostatic status in dogs with carcinoma or sarcoma is unknown and might allow earlier intervention.

OBJECTIVES

Estimate prevalence of thromboemboli and their association with hemostatic changes in dogs with carcinomas or sarcomas; estimate predictive values of hemostatic variables for thromboembolic disease in tumor-bearing dogs.

ANIMALS

Thirty-two dogs with sarcoma, 30 with carcinoma, 20 healthy age-controlled dogs.

METHODS

Prospective cross-sectional study. A hemostasis panel (platelet concentration, thromboelastography, fibrinogen and D-dimer concentration, factor X, VII and antithrombin activity) was performed in all dogs. Tumor-bearing dogs underwent complete post mortem and histopathological evaluation. Comparisons between healthy dogs and tumor-bearing dogs with and without intracavitary hemorrhage; and tumor-bearing dogs with and without microthrombi were analyzed.

RESULTS

Thromboembolic disease was identified in 32/62 (52%, 95% CI: 39%-65%) tumor-bearing dogs. Microthrombi were identified in 31/62 (50%, 95% CI: 37%-63%) dogs, 21/31 (68%, 95% CI: 49%-83%) had exclusively intra-tumoral microthrombi, 10/31 (32%, 95% CI: 17%-51%) had distant microthrombi. Macrothrombi were identified in 3 tumor-bearing dogs. Hemostatic changes potentially consistent with overt and non-overt disseminated intravascular coagulation were identified in some tumor-bearing dogs. D-dimer concentrations were significantly higher (P = .02) and platelet concentration significantly lower (P = .03) in tumor-bearing dogs with microthrombi compared to tumor-bearing dogs without microthrombi. D-dimer concentration above 500 ng/mL was 80% sensitive and 41% specific for the prediction of microthrombi presence.

CONCLUSION

The high microthrombi prevalence and concomitant hemostatic dysfunction in dogs with carcinomas or sarcomas has not previously been reported, though the clinical importance is unknown. Increased D-dimer concentration might increase suspicion of microthrombi.

New molecular targets in canine hemangiosarcoma-Comparative review and future of the precision medicine

Human angiosarcoma and canine hemangiosarcoma reveal similarities not only in their aggressive clinical behaviour, but especially in molecular landscape and genetic alterations involved in tumorigenesis and metastasis formation. Currently, no satisfying treatment that allows for achieving long overall survival or even prolonged time to progression does not exist. Due to the progress that has been made in targeted therapies and precision medicine the basis for a new treatment design is to uncover mutations and their functions as possible targets to provide tailored drugs for individual cases. Whole exome or genome sequencing studies and immunohistochemistry brought in the last few years important discoveries and identified the most common mutations with probably crucial role in this tumour development. Also, despite a lack of mutation in some of the culprit genes, the cancerogenesis cause may be buried in main cellular pathways connected with proteins encoded by those genes and involving, for example, pathological angiogenesis. The aim of this review is to highlight the most promising molecular targets for precision oncology treatment from the veterinary perspective aided by the principles of comparative science. Some of the drugs are only undergoing laboratory in vitro studies and others entered the clinic in the management of other cancer types in humans, but those used in dogs with promising responses have been mentioned as priorities.

Right atrial thrombus formation in a dog after successful electrical cardioversion for atrial fibrillation

Right atrial masses in dogs are commonly diagnosed as malignant tumors. This report describes a dog with a right atrial mass that appeared after successful electrical cardioversion of atrial fibrillation and resolved with antithrombotic treatment. A 9-year-old mastiff was presented for acute vomiting, and occasional cough of several weeks' duration. Ultrasonographic and radiographic examinations of the abdomen and chest identified mechanical ileus, as well as pleural effusion and pulmonary edema, respectively. Echocardiography indicated a dilated cardiomyopathy phenotype. During anesthetic induction for laparotomy, atrial fibrillation developed. Electrical cardioversion successfully restored sinus rhythm. An echocardiogram performed 2 weeks later disclosed a right atrial mass, which had not been apparent before cardioversion. Repeat echocardiography after 2 months of clopidogrel and enoxaparin treatment failed to detect the mass. Intra-atrial thrombus formation is possible after successful cardioversion of atrial fibrillation and should be considered as a differential diagnosis for echocardiographically detected atrial masses.

Use of intralesional cisplatin to successfully treat distal limb haemangiosarcoma in a foal

A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was performed at monthly intervals for three treatments. Four years post treatment with cisplatin, the horse remained in remission. This case report describes the diagnostic and treatment challenges for successful treatment of a primary haemangiosarcoma on the distal limb of a warmblood foal using intralesional cisplatin chemotherapy.

Hemorrhage and Sudden Death in a Cat with Pancreatic Hemangiosarcoma

A 15-year-old female, indoor, spayed, domestic shorthair cat was presented for post-mortem evaluation with a history of sudden death. A red-brown 3 cm x 4 cm neoplastic mass was identified within the body of the pancreas, along with multiple similar nodular structures within the omentum and liver. Associated lesions included hemoperitoneum, yellow discoloration of the peritoneal wall, and severe anemia. Spindle-shaped neoplastic cells exhibiting malignancy features, which occasionally contained within the cytoplasm haematoidin crystals and/or red blood cells, were observed during cytological examination. Histologically, the neoplastic cells were organized in short streams forming vascular spaces filled with erythrocytes. Immunohistochemically, the neoplastic cells were immunolabeled for vimentin and CD31, supporting the diagnosis of hemangiosarcoma. This report offers a complete post-mortem and histological evaluation of a rare tumor in cats with an unusual location and a comparative assessment of 3 anti-CD31 antibodies.

Hemangiosarcoma of the nasal planum in cats: five cases (2010-2021)

CASE SERIES SUMMARY

Nasal planum tumors are rare in cats, with squamous cell carcinoma over-represented. Other skin tumors have been reported in this location and though hemangiosarcoma frequently occurs on the skin of the head, these tumors localized to the nasal planum have not been specifically reported. The objectives of this study were to report the clinical findings and outcomes in cats diagnosed with hemangiosarcoma of the nasal planum. Medical records from four different institutions were reviewed to identify cats with a definitive diagnosis of hemangiosarcoma of the nasal planum. Five cats met the inclusion criteria. One cat was treated with palliative radiation therapy (RT) alone, two cats had lesions removed via an excisional biopsy by the primary care veterinarian and two cats had excisional biopsies performed at a referral institution. All four cats that received surgical treatment were treated with adjuvant strontium-90 therapy. The cat receiving palliative RT alone was lost to follow-up 311 days after treatment. At the time of writing, the survival time for 2/3 cats receiving surgery and strontium-90 was 365 days and 1381 days, respectively. One cat receiving this combination of therapy was lost to follow-up immediately after treatment. One cat developed tumor recurrence and a revision surgery via nasal planectomy and upper lip resection was performed 376 days following the initial surgery. Following revision, palliative RT was pursued. The cat was still alive at the time of writing 618 days after the initial procedure, with no evidence of recurrence.

RELEVANCE AND NOVEL INFORMATION

In this case series, surgery was the primary treatment used, but due to the location, only narrow or incomplete surgical margins were possible. RT (strontium-90 and/or palliative) was utilized to decrease the risk of recurrence.

The immunohistochemical detection of peroxiredoxin 1 and 2 in canine spontaneous vascular endothelial tumors

Peroxiredoxin (PRDX) is an antioxidant enzyme family with six isoforms (PRDX1-6). The main function of PRDXs is to decrease cellular oxidative stress by reducing reactive oxygen species, such as hydrogen peroxide, to H2O. Recently, it has been reported that PRDXs are overexpressed in various malignant tumors in humans, and are involved in the development, proliferation, and metastasis of tumors. However, studies on the expression of PRDXs in tumors of animals are limited. Therefore, in the present study, we immunohistochemically investigated the expression of PRDX1 and 2 in spontaneous canine hemangiosarcoma (HSA) and hemangioma (HA), as well as in selected normal tissue and granulation tissue, including newly formed blood vessels. Although there were some exceptions, immunolocalization of PRDX1 and 2 in normal canine tissues was similar to those in humans, rats, or mice. In granulation tissue, angiogenic endothelial cells were strongly positive for PRDX1 and 2, whereas quiescent endothelial cells in mature vessels were negative. Both PRDX1 and 2 were significantly highly expressed in HSA compared to HA. There were no significant differences in the expression of PRDX1 and 2 among the subtypes and primary sites of HSA. These results suggest that PRDX1 and 2 may be involved in the angiogenic phenotypes of endothelial cells in granulation tissue as well as in the behavior in the malignant endothelial tumors.

Hemorrhagic shock after contrast-enhanced ultrasound-guided liver biopsy: A case report of primary hepatic angiosarcoma

Primary hepatic angiosarcoma (PHA) is a rare, highly aggressive malignancy. There is no specificity in clinical manifestations, laboratory examinations and imaging examinations. The definitive diagnosis of PHA depends on pathological analysis. The gold standard method to obtain specimens is percutaneous transhepatic biopsy under the guidance of contrast-enhanced ultrasound (CEUS). However, CEUS-guided biopsy for PHA is controversial. If a biopsy is necessary, a comprehensive preoperative evaluation is essential. In addition, CEUS has an auxiliary value in diagnosing PHA. In this case, we present an elderly woman who underwent CEUS-guided liver mass biopsy. The patient developed hemorrhagic shock after biopsy.

Manipulating Histone Acetylation Leads to Antitumor Effects in Hemangiosarcoma Cells

Canine hemangiosarcoma (HSA) is a malignant tumor derived from endothelial cells. No effective treatment has yet been developed because of the lack of understanding of its pathogenesis. Histone acetylation, an epigenetic modification, is highly associated with cancer pathogenesis. Manipulating histone acetylation by histone deacetylase inhibitors (HDACi) or bromodomain and extraterminal domain inhibitors (BETi) is one approach to treat various cancers. However, the role of histone acetylation in HSA remains unknown. This study aimed to investigate how histone acetylation functions in HSA pathogenesis using two HDACi, suberanilohydroxamic acid (SAHA) and valproic acid (VPA), and one BETi, JQ1, in vitro and in vivo. Histone acetylation levels were high in cell lines and heterogeneous in clinical cases. SAHA and JQ1 induced apoptosis in HSA cell lines. HSA cell lines treated with SAHA and VPA upregulated inflammatory-related genes and attracted macrophage cell line RAW264 cells, which suggests that SAHA and VPA can affect immune responses. JQ1 stimulated autophagy and inhibited the cell cycle in HSA cell lines. Finally, we demonstrated that JQ1 suppressed HSA tumor cell proliferation in vivo although SAHA and VPA did not affect tumor growth. These results suggest that BETi can be alternative drugs for HSA treatment. Although further research is required, our study indicated that dysregulation of histone acetylation is likely to be involved in HSA malignancy. This article is protected by copyright. All rights reserved.

Surgical treatment of conjunctival hemangioma and hemangiosarcoma: A retrospective study of 52 dogs

OBJECTIVE

To review cases of canine conjunctival hemangioma (HA) and hemangiosarcoma (HSA) treated surgically at a referral center to establish success of surgical management, recurrence rates, and long-term outcomes for patients.

ANIMALS STUDIED

Retrospective record review of dogs that underwent surgery to remove histologically diagnosed conjunctival HA or HSA between April 2004 and April 2020 to collect data on signalment, tumor location, interval between initial presentation and surgery, tumor diagnosis, surgical dose, surgical margins, tumor size, recurrence and survival times.

RESULTS

A total of 52 dogs (60 tumors) were included. The mean age of affected dogs was 8.69 years; the most affected breed was the Border collie (n = 13, 25%). 28 tumors were HA (46.67%) and 32 HSA (53.33%). Tumors occurred in three locations: the lateral bulbar conjunctiva (n = 37, 61.67%), the third eyelid margin (n = 19, 31.67%), and the ventral conjunctival fornix (n = 4, 6.67%). There was no site predilection for HA versus HSA. 97% of tumors occurred in non-pigmented tissue. Corneal invasion was more likely to be a feature of malignant tumors. Five tumors were incompletely excised, one of which recurred. There was no statistical difference in likelihood of incomplete excision between HSA and HA. Six tumors (10%) recurred. HSA was not statistically more likely to recur than HA. Recurrence times ranged from 5 weeks to 1 year.

CONCLUSION

Surgical treatment of conjunctival HA and HSA is likely to be curative. There is a recurrence rate of 10% regardless of tumor type, and recurrence may be late in the course of the disease.

Prognostic value of sternal lymphadenopathy on malignancy and survival in dogs undergoing splenectomy

The purpose of this retrospective cohort study was to determine prevalence of sternal lymphadenopathy in a population of dogs undergoing splenectomy, and to evaluate if the prevalence was associated with splenic malignancy. In addition, the study investigated if survival in dogs diagnosed with hemangiosarcoma (HSA) differed between those with or without sternal lymphadenopathy at the time of surgery. Digital radiographs and medical records for dogs who underwent splenectomy from 2013 to 2016 where retrospectively reviewed. One hundred ninety-five dogs underwent splenectomy during the study period. The overall prevalence of sternal lymphadenopathy was 12.8%. The prevalence of sternal lymphadenopathy in dogs with hemangiosarcoma was 16.2% (12/74), other malignancy was 15.8% (3/19), and with a benign process 9.8% (10/102). There was no significant association between sternal lymphadenopathy with hemoperitoneum (p = .20) or between sternal lymphadenopathy and presence of neoplasia (p = .37). There was no significant difference in survival probability in all dogs with or without sternal lymphadenopathy (p = .073). However, sternal lymphadenopathy was associated with lower survival in 74 dogs with HSA (p = .036) and 19 with other splenic malignancies (p = .039). The presence of sternal lymphadenopathy should not be considered a negative prognostic indicator if present in dogs presenting with a hemoperitoneum. Although the presence of sternal lymphadenopathy at the time of initial presentation was not significantly associated with survival time in all dogs with splenic disease, it may have predictive value related to survival of dogs with splenic malignancy.

Epizootic neoplasia in a managed population of Atlantic bumper fish, Chloroscombrus chrysurus (Osteichthyes: Carangidae), at a public aquarium

Advances in fish medicine and husbandry have increased the average lifespans of specimens in managed aquarium populations. As a result, an increased incidence and variety of neoplasia is expected. This work characterizes diverse neoplasms arising within a managed population of Atlantic bumper fish acquired via repeated collections from the Charleston Harbor region. A total of 76 neoplasms were evaluated histologically from 41 of 45 fish that died or were killed over a 46-month period, including cutaneous hemangiomas and hemangiosarcomas, lepidocytomas and lepidosarcomas, fibromas, vertebral body or cutaneous osteomas, disseminated lymphomas, testicular leiomyomas, cutaneous or branchial fibrosarcomas, myxomas, fibroblastic lepidosarcoma, teratoid medulloepithelioma, ganglioglioma, malignant nerve sheath tumour, cardiac rhabdomyoma, cutaneous rhabdomyosarcoma, soft tissue sarcoma and renal adenoma. Perioral and cutaneous lesions of vascular and scale origin were observed most frequently. Other, often malignant, neoplasms arose within these benign lesions, resulting in extensive local tissue invasion. However, excluding disseminated lymphomas, metastasis was only detected in one case of hemangiosarcoma. These findings suggest early surgical intervention may limit tissue destruction and loss of display quality. This report details a variety of common and rare neoplasms in fish, as well as the first characterizations of neoplasia in Atlantic bumper and ganglioglioma in fish.

Candidate Glycoprotein Biomarkers for Canine Visceral Hemangiosarcoma and Validation Using Semi-Quantitative Lectin/Immunohistochemical Assays

Visceral hemangiosarcoma (HSA) is one of the more frequent cancers in dogs and has a high metastatic rate and poor prognosis, as clinical signs only become apparent in advanced stages of tumor development. In order to improve early and differential diagnostic capabilities and hence, prognosis for dogs with HSA, two types of biomarker are needed: a point-of-care diagnostic biomarker and a prognostic biomarker—preferentially based on samples obtained with minimally invasive methods. In this study, we applied a lectin magnetic bead array-coupled tandem mass spectrometry (LeMBA-MS/MS) workflow through discovery and validation phases to discover serum glycoprotein biomarker candidates for canine HSA. By this approach, we found that Datura stramonium (DSA), wheat germ agglutinin (WGA), Sambucus nigra (SNA), and Pisum sativum (PSA) lectins captured the highest number of validated candidate glycoproteins. Secondly, we independently validated serum LeMBA-MS/MS results by demonstrating the in situ relationship of lectin-binding with tumor cells. Using lectin-histochemistry and immunohistochemistry (IHC) for key proteins on tissues with HSA and semi-quantitation of the signals, we demonstrate that a combination of DSA histochemistry and IHC for complement C7 greatly increases the prospect of a more specific diagnosis of canine HSA.

Propranolol Sensitizes Vascular Sarcoma Cells to Doxorubicin by Altering Lysosomal Drug Sequestration and Drug Efflux

Angiosarcoma is a rare cancer of blood vessel-forming cells with a high patient mortality and few treatment options. Although chemotherapy often produces initial clinical responses, outcomes remain poor, largely due to the development of drug resistance. We previously identified a subset of doxorubicin-resistant cells in human angiosarcoma and canine hemangiosarcoma cell lines that exhibit high lysosomal accumulation of doxorubicin. Hydrophobic, weak base chemotherapeutics, like doxorubicin, are known to sequester within lysosomes, promoting resistance by limiting drug accessibility to cellular targets. Drug synergy between the beta adrenergic receptor (β-AR) antagonist, propranolol, and multiple chemotherapeutics has been documented in vitro, and clinical data have corroborated the increased therapeutic potential of propranolol with chemotherapy in angiosarcoma patients. Because propranolol is also a weak base and accumulates in lysosomes, we sought to determine whether propranolol enhanced doxorubicin cytotoxicity via antagonism of β-ARs or by preventing the lysosomal accumulation of doxorubicin. β-AR-like immunoreactivities were confirmed in primary tumor tissues and cell lines; receptor function was verified by monitoring downstream signaling pathways of β-ARs in response to receptor agonists and antagonists. Mechanistically, propranolol increased cytoplasmic doxorubicin concentrations in sarcoma cells by decreasing the lysosomal accumulation and cellular efflux of this chemotherapeutic agent. Equivalent concentrations of the receptor-active S-(-) and -inactive R-(+) enantiomers of propranolol produced similar effects, supporting a β-AR-independent mechanism. Long-term exposure of hemangiosarcoma cells to propranolol expanded both lysosomal size and number, yet cells remained sensitive to doxorubicin in the presence of propranolol. In contrast, removal of propranolol increased cellular resistance to doxorubicin, underscoring lysosomal doxorubicin sequestration as a key mechanism of resistance. Our results support the repurposing of the R-(+) enantiomer of propranolol with weak base chemotherapeutics to increase cytotoxicity and reduce the development of drug-resistant cell populations without the cardiovascular and other side effects associated with antagonism of β-ARs.

A neurological presentation caused by brain metastases in a dog with interventricular septal hemangiosarcoma

BACKGROUND

Brain metastases are well known for disseminated hemangiosarcoma involving the right atrium/auricle.

CASE REPORT

An 8-year-old male Australian Shepherd Dog presented with a 3-day history of circling to the left. A neurological examination revealed obtunded mentation, right hemi-inattention, bilateral strabismus towards the left side and absent physiological nystagmus. In addition, the dog had muffled heart sounds on auscultation and exercise-induced weakness. Laboratory findings included hypercoagulability and marked elevation in the C-reactive protein concentration. Electrocardiography detected a sinus rhythm with right bundle-branch block and ventricular bigeminy. Echocardiography revealed an extensive interventricular septal mass. Due to the grave prognosis, the owners elected for euthanasia, and a complete necropsy was performed. The main pathological findings were an interventricular septal and left ventricular hemangiosarcoma, with metastases in the brain, lungs, spleen and adrenal glands. No evidence of tumour infiltration was found in the right atrium.

CONCLUSION

To the authors' knowledge, this is the first report of neurological signs due to confirmed brain metastases in a dog with interventricular septal hemangiosarcoma. Although the right atrium is the main location for cardiac hemangiosarcoma, the interventricular septum should be evaluated in all cases.

Triple-Phase Multidetector Computed Tomography in Distinguishing Canine Hepatic Lesions

Simple Summary

The goal of this study was to find any associations between the histologic diagnosis and the radiodensity of liver lesions. Thirty-one dogs with focal or multifocal liver lesions undergoing computed tomography examination were included in the study. Computed tomography examinations were performed before and after the application of a contrast medium, and postcontrast images were obtained in three different vascular phases; the arterial, portal, and delayed venous phases. A histological diagnosis was subsequently obtained for all of the dogs. From the results, no significant differences were identified between the benign and malignant liver lesions, nor between the individual histological types of lesions. The conclusion from this study is that triple-phase contrast-enhanced computed tomography cannot differentiate between benign and malignant liver lesions. Biopsy and further histological analysis are necessary.

Abstract

The liver has a unique vascular supply, and triple-phase contrast-enhanced computed tomography examinations are being performed in order to characterize liver lesions. This study aimed to look for any associations between the attenuation values of liver lesions and their histological classification. The inclusion criteria for this retrospective study were focal or multifocal liver lesions and histological diagnosis. All of the dogs underwent pre-contrast and triple-phase postcontrast computed tomography (CT) examinations with identical timings of the postcontrast series. Thirty-one dogs were included in the study, and various benign and malignant pathologies were identified. The results did not identify any significant differences between the benign and malignant liver lesions, nor between the individual histological diagnoses. Inflammatory lesions were significantly different compared to the normal liver parenchyma, and significant hypoattenuation was found in the portal and delayed venous phases. Hemangiosarcomas were significantly hypoattenuating to the normal liver parenchyma in the pre-contrast and arterial phases, and also to all of the benign lesions in the arterial phase. The other pathologies showed variable attenuation patterns in the different postcontrast phases, and differentiation was not possible. On the basis of this study, triple-phase contrast-enhanced computed tomography cannot differentiate between benign and malignant liver lesions, and biopsy and further histological analysis are necessary.

A Review of Proliferative Vascular Disorders of the Central Nervous System of Animals

In disease, blood vessel proliferation has many salient roles including in inflammation, when granulation tissue fills superficial defects, or in the recanalization of an occluded blood vessel. Sometimes angiogenesis goes awry-granulation can be exuberant, and plexiform proliferation of vascular components can contribute to pulmonary hypertension. This review focuses on the diverse manifestations of pathologic vascular overgrowth that occur in the brain, spinal cord, and meninges of animals from birth until old age. Entities discussed include systemic reactive angioendotheliomatosis in which glomeruloid vascular proliferations are encountered in various organs including the central nervous system (CNS). The triad of CNS vascular malformations, hamartomas, and benign vascular proliferations are an especially fraught category in which terminology overlap and the microscopic similarity of various disorders makes diagnostic classification incredibly challenging. Pathologists commonly take refuge in "CNS vascular hamartoma" despite the lack of any unique histopathologic features and we recommend that this diagnostic category be abandoned. Malformative lesions that are often confusing and have similar features; the conditions include arteriovenous malformation, cavernous angioma, venous angioma, and capillary telangiectases. Meningioangiomatosis, a benign meningovascular proliferation with dual components, is a unique entity seen most commonly in young dogs. Last, accepted neoplastic conditions range from lower-grade locally acquired growths like hemangioblastoma (a tumor of mysterious interstitial stromal cells encountered in the setting of abundant capillary vasculature proliferation), the rare hemangioendothelioma, and the highly malignant and invariably multifocal metastatic hemangiosarcoma. Additionally, this review draws on the comparative medical literature for further insights into this problematic topic in pathology.

Radiation-induced angiosarcoma: case report

Angiosarcoma of the breast accounts for less than 1% of breast tumors. This tumor may be primary or secondary to previous radiation therapy and it is also named "radiogenic angiosarcoma of the breast", which is still a rare entity with a poor prognosis. So far, there are only 307 cases reported about these tumors in the literature. We present a case of a 73-year-old woman with a prior history of breast-conserving treatment of right breast cancer, exhibiting mild pinkish skin changes in the ipsilateral breast. Her mammography was consistent with benign alterations (BI-RADS 2). On incisional biopsy specimens, hematoxylin-eosin showed atypical vascular lesion and suggested immunohistochemisty for diagnostic elucidation. Resection of the lesions was performed and histology showed radiogenic angiosarcoma. The patient underwent simple mastectomy. Immunohistochemistry was positive for antigens related to CD31 and CD34, and C-MYC oncogene amplification, confirming the diagnosis of angiosarcoma induced by breast irradiation. A delayed diagnosis is an important concern. Initial skin changes in radiogenic angiosarcoma are subtle, therefore, these alterations may be confused with other benign skin conditions such as telangiectasia. We highlight this case clinical aspects with the intention of alerting to the possibility of angiosarcoma of the breast in patients with a previous history of adjuvant radiation therapy for breast cancer treatment. Sixteen months after the surgery the patient remains asymptomatic.

Angiosarcomas of Primary Gynecologic Origin - A Case Series and Review of the Literature

BACKGROUND/AIM

Angiosarcoma of primary gynecologic origin is an extremely rare and highly malignant tumor of endothelial origin with a 5-year survival rate of less than 35%. To date, only 61 cases have been described in the literature. The aim of this study was to present more cases and discuss potential therapy options.

CASE REPORT

The following case series presents three cases of gynecologic angiosarcomas that were under therapy at the Charité - University medicine of Berlin from June 2014 to February 2018.

RESULTS

Two of the cases deal with primary angiosarcomas of the uterus whereas the third case was diagnosed after the suspicion of a recurrence of a poorly differentiated squamous cell carcinoma of the cervix uteri. In case one a 75-year old patient with initial postmenopausal bleeding and a tumor mass of the uterus is described. After surgery a hemangiosarcoma of the uterus was confirmed. After two months the patient presented with a presacral peritoneal sarcomatosis. Chemotherapy of weekly paclitaxel was administered. Case two deals with a patient presenting with abdominal pain. A uterine sarcoma with infiltration of the parametry and angiosarcomatosis peritonei was diagnosed during an emergency laparotomy because of spontaneous peritoneal bleeding. Moreover, osseous metastasis was found. The patient underwent weekly paclitaxel. Due to tumor progression, chemotherapy was changed to doxorubicin and olaratumab and radiotherapy was induced. The patient died 33 months after initial diagnosis. Case three describes a 34-year old patient with suspected local recurrence of cervical cancer with infiltration of the bladder. During TURB an angiosarcoma was found. Following laparoscopy revealed peritoneal metastasis. The patient underwent weekly paclitaxel followed by a paclitaxel and pazopanib maintainance therapy which showed a regression. Due to progression afterwards, chemotherapy was changed to gemcitabine and docetaxel and gemcitabine monotherapy. The patient died 33 months after initial diagnosis.

CONCLUSION

Even though there is no evidence on standard treatment of this extremely rare and aggressive tumor entity of the female genital tract the patients showed the longest stability of disease during chemotherapy with weekly paclitaxel.

Assisting Decision-Making on Age of Neutering for 35 Breeds of Dogs: Associated Joint Disorders, Cancers, and Urinary Incontinence

Neutering (including spaying) of male and female dogs in the first year after birth has become routine in the U.S. and much of Europe, but recent research reveals that for some dog breeds, neutering may be associated with increased risks of debilitating joint disorders and some cancers, complicating pet owners' decisions on neutering. The joint disorders include hip dysplasia, cranial cruciate ligament tear or rupture, and elbow dysplasia. The cancers include lymphoma, mast cell tumor, hemangiosarcoma, and osteosarcoma. In previous studies on the Golden Retriever, Labrador Retriever and German Shepherd Dog, neutering before a year of age was associated with increased risks of one or more joint disorders, 2-4 times that of intact dogs. The increase was particularly seen with dogs neutered by 6 months of age. In female Golden Retrievers, there was an increase in one or more of the cancers followed to about 2-4 times that of intact females with neutering at any age. The goal of the present study was to expand and use the same data collection and analyses to cover an additional 29 breeds, plus three varieties of Poodles. There were major breed differences in vulnerability to neutering, both with regard to joint disorders and cancers. In most cases, the caregiver can choose the age of neutering without increasing the risks of these joint disorders or cancers. Small-dog breeds seemed to have no increased risks of joint disorders associated with neutering, and in only two small breeds (Boston Terrier and Shih Tzu) was there a significant increase in cancers. To assist pet owners and veterinarians in deciding on the age of neutering a specific dog, guidelines that avoid increasing the risks of a dog acquiring these joint disorders or cancers are laid out for neutering ages on a breed-by-breed and sex basis.

Thalidomide Reduces Vascular Endothelial Growth Factor Immunostaining in Canine Splenic Hemangiosarcoma

Hemangiosarcomas (HSA) are common neoplasms of dogs that often metastasize and are typically fatal. Recently it was demonstrated that thalidomide extends the survival time of dogs with HSA, potentially due to thalidomide-induced inhibition of vascular endothelial growth factor (VEGF) production by the neoplastic cells. To investigate this, immunostaining was used to evaluate VEGF within HSA metastases that developed after thalidomide treatment. The immunostaining was then compared to VEGF immunostaining in primary tumors from the same dogs prior to treatment with thalidomide and in metastatic tumors from untreated dogs with splenic HSA. Immunostaining was scored from 1 to 4 for each sample. Immunostaining in the metastatic lesions that had been treated with thalidomide had a mean immunostaining score of 1.4 which was significantly lower than the mean score in the corresponding primary splenic HSA (3.8, p = 0.02) and in metastases from untreated dogs (3.5, p = 0.02). This supports the hypothesis that thalidomide prolongs survival time in dogs with HSA due to inhibition of VEGF production by the neoplastic cells. As VEGF remained visible within HSAs exposed to thalidomide, additional treatments to inhibit VEGF production may further prolong survival times of dogs with these common canine neoplasms.

Extracellular vesicular microRNAs as potential biomarker for early detection of doxorubicin-induced cardiotoxicity

Background

Long‐term use of doxorubicin (DOX) is limited by cumulative dose‐dependent cardiotoxicity.

Objectives

Identify plasma extracellular vesicle (EV)‐associated microRNAs (miRNAs) as a biomarker for cardiotoxicity in dogs by correlating changes with cardiac troponin I (cTnI) concentrations and, echocardiographic and histologic findings.

Animals

Prospective study of 9 client‐owned dogs diagnosed with sarcoma and receiving DOX single‐agent chemotherapy (total of 5 DOX treatments). Dogs with clinically relevant metastatic disease, preexisting heart disease, or breeds predisposed to cardiomyopathy were excluded.

Methods

Serum concentration of cTnI was monitored before each treatment and 1 month after the treatment completion. Echocardiography was performed before treatments 1, 3, 5, and 1 month after completion. The EV‐miRNA was isolated and sequenced before treatments 1 and 3, and 1 month after completion.

Results

Linear mixed model analysis for repeated measurements was used to evaluate the effect of DOX. The miR‐107 (P = .03) and miR‐146a (P = .02) were significantly downregulated whereas miR‐502 (P = .02) was upregulated. Changes in miR‐502 were significant before administration of the third chemotherapeutic dose. When stratifying miRNA expression for change in left ventricular ejection fraction, upregulation of miR‐181d was noted (P = .01). Serum concentration of cTnI changed significantly but only 1 month after treatment completion, and concentrations correlated with left ventricular ejection fraction and left ventricular internal dimension in diastole.

Conclusion and Clinical Significance

Downregulation of miR‐502 was detected before significant changes in cTnI concentrations or echocardiographic parameters. Further validation using a larger sample size will be required.

Expression of Hematopoietic Stem and Endothelial Cell Markers in Canine Hemangiosarcoma

Several chemicals and pharmaceuticals increase the incidence of hemangiosarcomas (HSAs) in mice, but the relevance to humans is uncertain. Recently, canine HSAs were identified as a powerful tool for investigating the pathogenesis of human HSAs. To characterize the cellular phenotype of canine HSAs, we evaluated immunoreactivity and/or messenger RNA (mRNA) expression of markers for hematopoietic stem cells (HSCs), endothelial cells (ECs), a tumor suppressor protein, and a myeloid marker in canine HSAs. Neoplastic canine cells expressed EC markers and a myeloid marker, but expressed HSC markers less consistently. The canine tumor expression results were then compared to previously published immunoreactivity results for these markers in human and mouse HSAs. There are 2 noteworthy differences across species: (1) most human HSAs had HSC marker expression, indicating that they were comprised of tumor cells that were less differentiated than those in canine and mouse tumors; and (2) human and canine HSAs expressed a late-stage EC maturation marker, whereas mouse HSAs were negative, suggesting that human and canine tumors may retain greater differentiation potential than mouse tumors. These results indicate that HSA development is variable across species and that caution is necessary when discussing translation of carcinogenic risk from animal models to humans.

Spontaneous abdominal hemangiosarcoma in a ferret

Herein, we describe the case of a 6-year-old female ferret that died within a few days of the onset of anorexia and reduced spontaneous locomotor activity. Necropsy revealed a dark red abdominal mass of unknown origin between the right lobes of the pancreas and the proximal jejunum, with massive blood retention in the peritoneal cavity. Histopathologically, spindle-shaped or sometimes polygonal tumor cells were proliferating with irregularly shaped vascular spaces containing blood components and surrounding-tissue infiltration. In some areas, tumor cells formed distinctly dilated blood vessel-like structures. Immunohistochemically, most of the tumor cells were strongly positive for CD31, but factor VIII-related antigen immunoreactivity was confined to the area with dilated blood vessel-like structures. Based on these findings, the tumor was diagnosed as an abdominal hemangiosarcoma. Abdominal hemangiosarcoma excluding cases of the liver and spleen are rare in ferrets.

Magnetic resonance imaging findings of an intradural extramedullary hemangiosarcoma in a dog

An 11-year-old male Miniature Dachshund was referred for acute neurological deficits in the pelvic limbs. T2-weighted magnetic resonance imaging revealed that the spinal cord at the L1-2 intervertebral disc space was heterogeneously hyperintense in the sagittal plane and was mildly compressed from the ventral side by a small hypointense mass in the transverse plane. However, the lesion showed mass enhancement and severe spinal cord compression on post-contrast T1-weighted imaging. On three-dimensional myelography, a “golf tee sign” was observed around the mass. Therefore, we diagnosed an intradural extramedullary lesion. The mass was surgically removed and histologically diagnosed as a hemangiosarcoma. The “golf tee sign” observed on magnetic resonance myelography may be useful for distinguishing intradural extramedullary masses from intramedullary masses.

A radiological and clinical description of metastatic angiosarcoma simulating a hydatid cyst

Los angiosarcomas son sarcomas malignos que se originan en las células endoteliales vasculares. Su diagnóstico diferencial es muy amplio debido a su parecido con otras enfermedades, como las parasitarias, y usualmente es un diagnóstico por exclusión. La neurocisticercosis y la hidatidosis cerebral son parasitosis intestinales que pueden comprometer el sistema nervioso central y tienen mayor incidencia en los países suramericanos.

El diagnóstico se establece a partir del perfil epidemiológico, el estudio parasitológico, la apariencia radiológica de las lesiones y el estudio de histopatología del espécimen.

Se presenta el caso de una adolescente con factores de riesgo para parasitosis y neuroimágenes sugestivas de hidatidosis cerebral, cuyo diagnóstico definitivo fue angiosarcoma cardiaco metastásico.

Radiation-induced angiosarcoma of the breast: A review

Angiosarcoma is a rare, aggressive malignant vascular neoplasm with poor prognosis that has a predilection for skin and superficial soft tissue. It can arise spontaneously or in association with factors like chronic lymphedema or radiation therapy. Radiotherapy used to treat invasive breast tumors is a known risk factor for the development of the so-called radiation-induced angiosarcoma (RIAS), a condition that has been described in the literature with increasing frequency. Radiation-induced angiosarcoma of the breast usually arises on the previously irradiated skin area several years after radiotherapy and presents as painless multifocal erythematous patches or plaques similar to a hematoma. Cutaneous biopsy is essential for the diagnosis. Histologically, RIAS is characterized by irregular anastomosing vessels lined by endothelial cells showing nuclear atypia. Treatment is mostly surgical, and mastectomy with negative margins is considered the standard procedure. However, recurrences are common, and an approach combining surgery, chemo- and radiotherapy may be more effective. The purpose of this study is to review the most recent medical literature on RIAS of the breast, with emphasis on its pathophysiology, clinical and histological features and current treatment options.

Understanding the Efficiency of Splenic Hemangiosarcoma Diagnosis Using Monte Carlo Simulations

Hemangiosarcoma is a common neoplasm of the spleen in older dogs. However, diagnosis is complicated by necrosis and hemorrhage, which can mimic a number of benign processes. Currently, there is no consensus about the number of sections pathologists should examine to rule out hemangiosarcoma. To answer this question, we examined 413 histopathologic sections from 50 cases of canine hemangiosarcoma (mean: 8.1 sections per case; range, 5-14). Each section had the presence or absence of hemangiosarcoma determined by 2 board-certified anatomic pathologists. Then, 100 Monte Carlo simulations were performed, randomly selecting sections from each case 10 000 times and the results averaged. These simulations suggest that examination of 5 sections from a spleen with hemangiosarcoma yields a 95.02% chance of diagnosing hemangiosarcoma, while examination of 10 sections yields a 98.59% chance of diagnosis when hemangiosarcoma is in fact present. The data emphasize the need to submit the entire spleen for histopathologic examination in suspected cases of hemangiosarcoma and suggest that 5 sections obtained by a trained individual are likely sufficient for diagnosis.

Adjuvant anthracycline-based vs metronomic chemotherapy vs no medical treatment for dogs with metastatic splenic hemangiosarcoma: A multi-institutional retrospective study of the Italian Society of Veterinary Oncology

Treatment options for dogs with metastatic (stage III) splenic hemangiosarcoma are limited. A doxorubicin-based chemotherapy regimen is commonly administered; however, there are no published data to support this practice. The aim of this study was to investigate the impact of maximum-tolerated-dose chemotherapy (MTD), metronomic chemotherapy (MC) and no adjuvant treatment on outcome in dogs with stage III splenic hemangiosarcoma undergoing splenectomy. Medical records of dogs with stage III splenic hemangiosarcoma that underwent splenectomy followed by MTD chemotherapy, MC or no adjuvant treatment were retrieved. Time to progression (TTP), survival time (ST) and toxicity were evaluated. One hundred three dogs were identified: 23 received adjuvant MTD, 38 MC and 42 were not medically treated. Overall median TTP and ST were 50 (95% confidence interval [CI], 39-61) and 55 days (95% CI, 43-66), respectively. Dogs treated with adjuvant MTD had a significantly longer TTP and ST compared with dogs receiving MC (median TTP, 134 vs 52 days, P = .025; median ST, 140 vs 58 days, P = .023, respectively). Dogs treated by splenectomy only had the shortest median TTP (28 days) and ST (40 days). However, treatment-related adverse events (AEs) were significantly more frequent in the MTD group (P = .017). The outcome for dogs with metastatic splenic hemangiosarcoma is poor. While MTD showed greater efficacy compared to MC, toxicity was higher in this group. Treatment-related AEs need to be carefully balanced against this modest survival prolongation when offering adjuvant MTD to dogs with advanced stage hemangiosarcoma.

Primary Epithelioid Angiosarcoma of the Breast: A Rare and Challenging Biopsy Diagnosis

BACKGROUND Primary angiosarcoma of the breast is a rare neoplasm, accounting for less than 0.04% of all breast cancers. Epithelioid angiosarcoma is even more unusual with only a handful of cases reported in literature. Differentiating this from other breast malignancy is a challenge. There have been conflicting reports regarding factors that affect prognosis. We present a case of primary epithelioid angiosarcoma of the breast, and also discuss the prognostic and differential diagnostic issues. CASE REPORT A 70-year old female presented with slowly enlarging fungating mass in the right breast with a necrotic center and serosanguineous discharge. Initial biopsy done at an outside institution reported the lesion as carcinosarcoma. Histologic sections showed cellular, infiltrative neoplasm with extensive necrosis and ectatic vascular proliferations lined by plump endothelial cells. Infiltrative cells were spindle-shaped with vacuolated cytoplasm and marked anisonucleosis in myxoid background. Mitotic activity was brisk. CAM5.2, AE1/AE3, and CD31 were positive. Proliferation index was high. Estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor 2 (HER2)/neu were negative. CONCLUSIONS Primary epithelioid angiosarcoma of the breast can present as a diagnostic dilemma in needle biopsies. This malignancy may mimic carcinoma or benign endothelial lesions. This entity is important to be recognized because it carries poor prognostic risk and requires distinct treatment modalities different from the usual epithelial breast neoplasms.

Primary pulmonary angiosarcoma: case reports and review of the literature

Pulmonary artery angiosarcoma is a rare malignant vascular tumor with an aggressive clinical course and a poor prognosis. Hemoptysis and shortness of breath have been reported as common clinical presentations. The exact clinicopathology is unknown. A tissue specimen obtained by percutaneous fine-needle aspiration cytology or open/thoracoscopic biopsy can confirm the diagnosis based on histopathological and immunohistochemical features. The differential diagnosis includes pulmonary thromboembolism, vascular malformations, and lung carcinoma. There is a paucity of literature describing this tumor, with only a few case reports available. There is also a lack of standardized guidelines for management, which further worsens the survival outcome. We report 3 cases of pulmonary artery angiosarcoma and review the recent literature.

Evaluation of hepatic tumor portal perfusion using mesenteric angiography: A pilot study in 5 dogs

BACKGROUND

Mesenteric angiography is a sensitive method for visualizing portal perfusion in the dog.

OBJECTIVES

To evaluate hepatic portal perfusion in dogs with incompletely resectable hepatic tumors using mesenteric angiography.

ANIMALS

Five client-owned dogs with incompletely resectable hepatic tumors evaluated with mesenteric angiography.

METHODS

Retrospective case series. Electronic medical records at the Animal Medical Center were analyzed to identify dogs that underwent mesenteric portography to determine blood flow to nonresectable hepatic tumors and subsequently determine ideal routes for transarterial embolization, vascular stent placement, or both. The images obtained from mesenteric angiography were analyzed and compared to those obtained from computed tomography angiography.

RESULTS

Portography was accomplished using direct mesenteric venography in 3 dogs with hepatocellular carcinoma (HCC), cranial mesenteric arteriography in 1 dog with hepatic adenoma or well-differentiated HCC, and via splenic arteriovenous fistula in 1 dog with diffuse hepatic hemangiosarcoma metastases. Mean pixel densities in areas of hepatic tumor growth identified statistically significant decreases in portal blood flow (P = .02) compared to normal hepatic parenchyma.

CONCLUSIONS AND CLINICAL IMPORTANCE

Initial findings indicate that the blood supply to large and metastatic hepatic tumors in dogs may correlate with that in humans, such that the majority of the tumor blood supply arises from the hepatic artery and not the portal vein. Differences in blood supply between normal hepatic parenchyma and hepatic tumors might be exploited by developing selective tumor therapies such as arterial embolization or chemoembolization that largely spare normal liver tissue. Further investigation is warranted.