Topic:Cancer
Cancer in horses encompasses a range of neoplastic diseases that affect various tissues and organs in equine species. These conditions involve the uncontrolled growth of abnormal cells, which can form tumors and potentially spread to other parts of the body. Common types of cancer in horses include sarcoids, squamous cell carcinoma, and melanoma, each with distinct characteristics and clinical presentations. Diagnosis often involves a combination of physical examination, imaging techniques, and histopathological analysis. Treatment options vary based on the type and stage of cancer and may include surgical intervention, chemotherapy, and radiation therapy. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, pathophysiology, diagnostic methods, and treatment strategies for cancer in horses.
Comparison of the levels of Equus caballus papillomavirus type 2 (EcPV-2) DNA in equine squamous cell carcinomas and non-cancerous tissues using quantitative PCR. Equus caballus papillomavirus type 2 (EcPV-2) infection has been associated with equine genital squamous cell carcinomas (SCCs). However, quantitative PCR (qPCR) has not been performed to determine viral copy numbers within these lesions. Additionally, the frequency with which EcPV-2 can be detected in other common sites of equine SCC development remains uncertain. The aim of this study was to develop a qPCR assay to estimate the viral load in a variety of equine tissue samples. These included 40 SCC lesions, 19 penile non-SCC or precursor disease lesions, and 222 tissues without observable le...
Multiple glucagon-producing pancreatic neuroendocrine tumors in a horse (Equus caballus). Pancreatic neuroendocrine tumors of glucagon-producing cells are extremely rare in domestic animals. In this report, we describe for the first time, to our knowledge, the incidental finding of multiple glucagon-producing neuroendocrine tumors of the pancreas of a horse. The animal was euthanized due to severe local infection after tooth extraction. On postmortem examination, multiple white nodules of up to 4 cm in diameter were observed in the pancreas. Histologically, pancreatic nodules had the appearance of neuroendocrine neoplasms with positive immunoreactivity for glucagon, synaptophysin, ...
Changes in DNA methylation patterns and repetitive sequences in blood lymphocytes of aged horses. It is known that aged organisms have modified epigenomes. Epigenetic modifications, such as changes in global and locus-specific DNA methylation, and histone modifications are suspected to play an important role in cancer development and aging. In the present study, with the well-established horse aging model, we showed the global loss of DNA methylation in blood lymphocytes during juvenile-to-aged period. Additionally, we tested a pattern of DNA methylation of ribosomal DNA and selected genes such as IGF2 and found no significant changes during development and aging. We asked if genetic compo...
A case report of lung cancer in a horse trainer caused by exposure to respirable crystalline silica: an exposure assessment. Here, we present a case of lung cancer in a 48-year-old male horse trainer. To the best of our knowledge, this is the first such case report to include an exposure assessment of respirable crystalline silica (RCS) as a quartz. The trainer had no family history of lung cancer. Although he had a 15 pack/year cigarette-smoking history, he had stopped smoking 12 years prior to his diagnosis. For the past 23 years, he had performed longeing, and trained 7-12 horses per day on longeing arena surfaces covered by recycled sands, the same surfaces used in race tracks. We investigated his workplace RCS ...
Fumonisin B(1): a neurotoxic mycotoxin. Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium spp. moulds that contaminate crop, predominantly maize, all around the world. More than 15 types of fumonisins have been indentified so far, but FB(1) is the most abundant and toxicologically the most significant one. FB(1) has a wide range of toxic effects, depending on animal species. In horses FB(1) causes equine leukoencephalomalacia (ELEM), in pigs pulmonary oedema and in experimental rodents nephrotoxicity and hepatotoxicity. In humans exposure to FB(1) is linked with higher incidence of primary liver cancer and oesophageal cance...
Equine sarcoids: Bovine Papillomavirus type 1 transformed fibroblasts are sensitive to cisplatin and UVB induced apoptosis and show aberrant expression of p53. Bovine papillomavirus type 1 infects not only cattle but also equids and is a causative factor in the pathogenesis of commonly occurring equine sarcoid tumours. Whilst treatment of sarcoids is notoriously difficult, cisplatin has been shown to be one of the most effective treatment strategies for sarcoids. In this study we show that in equine fibroblasts, BPV-1 sensitises cells to cisplatin-induced and UVB-induced apoptosis, a known cofactor for papillomavirus associated disease, however BPV-1 transformed fibroblasts show increased clonogenic survival, which may potentially limit the therapeut...
O(6)-methylguanine-DNA methyltransferase in equine sarcoids: molecular and epigenetic analysis. Bovine papillomaviruses (BPVs) types 1 and 2 are the only known papillomaviruses able to jump the species. In fact, BPVs 1/2 induce neoplasia in their natural bovine host but infection is also associated to neoplastic skin lesions in equids termed sarcoids. The equine sarcoid is considered to be the most common equine cutaneous tumour worldwide for which no effective therapy is available. Very little is known about the molecular mechanisms underlying tumourigenesis, although genes contributing to sarcoid development have been identified. Several studies associate the development of cancer to t...
Lymphoma risk in livestock farmers: results of the Epilymph study. We explored the risk of lymphoma and its most prevalent subtypes associated with occupational contact with livestock, and whether risk was modified by age at first contact, in 2,348 incident lymphoma cases and 2,462 controls who participated in the EPILYMPH case-control study. A detailed occupational history was collected in cases and controls, including working in a livestock farm, species of livestock, its approximate number and circumstances of contact. For each disease outcome, and each type of livestock, odds ratios (OR) and their 95% confidence intervals (95% CI) were calculated using un...
Multicentric T-cell lymphoma presenting as inferior palpebral swelling in a Standardbred mare. A 6-year-old Standardbred mare that presented with bilateral palpebral swelling and a left corneal ulcer was diagnosed with a multicentric T-cell lymphoma. Other clinical findings included submandibular lymphadenopathy and oedema, pharyngeal oedema and rhinitis. Prior to euthanasia the horse developed keratomalacia, the onset of which was coincidental with the use of high doses of topical and systemic corticosteroids. Although an unusual presentation, palpebral swelling should be considered as a clinical sign of lymphoma.
[Successful treatment of an equine sarcoid. Case report on a combined surgical and photodynamic therapy]. The case report describes the surgical and photodynamic treatment (PDT) of an equine sarcoid in a 6-year-old gelding. A mass on the ventral prepuce, several tumours on the lateral aspect of the prepuce and one sarcoid on the front aspect of the chest were treated. For PDT, Temoporfin (Fospeg® Biolitec AG, Jena) at a concentration of 0.15mg/ml was injected locally. The subsequent irradiation was performed using a red-light laser (652nm) with an energy density of 10J/cm². The mass on the ventral aspect of the prepuce and some of the lateral tumours displayed total remission. The remaining tumo...
EcPV2 DNA in equine papillomas and in situ and invasive squamous cell carcinomas supports papillomavirus etiology. Equine penile papillomas, in situ carcinomas, and invasive carcinomas are hypothesized to belong to a continuum of papillomavirus-induced diseases. The former ones clinically present as small grey papules, while the latter 2 lesions are more hyperplasic or alternatively ulcerated. To test the hypothesis that these lesions are papillomavirus-induced, samples of 24 horses with characteristic clinical and histologic findings of penile papillomas or in situ or invasive squamous cell carcinomas were collected. As controls, 11 horses with various lesions--namely, Balanoposthitis (6 cases), melanoma ...
Benign intraocular teratoid medulloepithelioma causing glaucoma in an 11-year-old Arabian mare. An 11-year-old Arabian mare was presented for investigation of a visible, pale-colored intraocular mass in the right eye. Results: An intraocular mass was detected clinically and ultrasonographically as originating from the superior temporal quadrant of the ciliary body and iris and causing secondary glaucoma. The echodense mass was occupying the majority of the vitreous chamber and extended into the anterior chamber. The left eye appeared normal. Results: Enucleation was recommended for therapeutic and diagnostic purposes. No adjuvant treatment was given. Histopathological examination demonst...
Copy number expansion of the STX17 duplication in melanoma tissue from Grey horses. Greying with age in horses is an autosomal dominant trait, associated with loss of hair pigmentation, melanoma and vitiligo-like depigmentation. We recently identified a 4.6 kb duplication in STX17 to be associated with the phenotype. The aims of this study were to investigate if the duplication in Grey horses shows copy number variation and to exclude that any other polymorphism is uniquely associated with the Grey mutation. Results: We found little evidence for copy number expansion of the duplicated sequence in blood DNA from Grey horses. In contrast, clear evidence for copy number expansio...
Congenital ascites due to hepatoblastoma with extensive peritoneal implantation metastases in a premature equine fetus. A premature dead equine fetus with excessive fluctuating distension of the abdomen was delivered by extraction. Post-mortem examination revealed ascites and a solitary, irregular, bulging, multinodular, firm, yellow mass of 25 cm in diameter in the right liver lobe. Extensive peritoneal implantation metastases were present. The masses were composed of polygonal embryonal cells arranged in sheets and nests. Based on the immunohistochemical expression of Ki67, low molecular weight cytokeratin and alpha-1 fetoprotein, a diagnosis of hepatoblastoma with peritoneal implantation metastases was made....
Determination of serum anti-Müllerian hormone concentrations for the diagnosis of granulosa-cell tumours in mares. Endocrinological assays are important for evaluation of mares with granulosa-cell tumours (GCTs), and our research in mares indicates that anti-Müllerian hormone (AMH) may be a good biomarker for this type of ovarian tumour. Objective: To evaluate the use of serum AMH concentrations for endocrine diagnosis of GCTs in mares. Methods: Archived serum samples (n = 403) previously assayed for determination of serum inhibin, testosterone and progesterone concentrations (GCT panel) were assayed for serum AMH concentrations using a heterologous enzyme-linked immunosorbent assay previously validated b...
Ocular manifestations of a metastatic adenocarcinoma in a horse. A 10-year-old German Warmblood gelding was referred to the Equine Department of the Vetsuisse Faculty, University of Zurich, Switzerland, for an iris mass OD, lethargy, intermittent fever, and coughing. Ophthalmic examination revealed a 7 × 9 mm raised, fleshy, whitish to pinkish, vascularized iris mass at the 2 o`clock position OD. Fundic examination showed multifocal round, brown to black, slightly raised lesions with indistinct margins and a surrounding hyperreflective zone OU. Physical examination revealed a temperature of 39.2 °C, sinus tachycardia, preputial and ventral edema, and an e...
RACK1, a clue to the diagnosis of cutaneous melanomas in horses. Melanocytic proliferations are common in horses but the diagnosis of malignancy is not always straightforward. To improve diagnosis and prognosis, markers of malignancy are needed. Receptor for activated C kinase 1 (RACK1) protein may be such a marker. RACK1 was originally found to characterize malignant melanocytic lesions in the Melanoblastoma-bearing Libechov minipig (MeLiM) and, later, in human patients. Our purpose was to investigate the value of RACK1 in the classification of cutaneous melanocytic proliferations in horses. Results: Using immunofluorescence, we report here that both MITF ...
DNA hypomethylation and oxidative stress-mediated increase in genomic instability in equine sarcoid-derived fibroblasts. It is widely accepted that equine sarcoid disease, the most common skin associated neoplasm in equids, is induced by bovine papillomavirus (BPV-1). Although BPV-1 DNA has been found in almost all examined sarcoids so far, its detailed impact on the horse's host cell metabolism is largely unknown. We used equine fibroblast cell lines originating from sarcoid biopsies to study BPV-1-associated changes on DNA methylation status and oxidative stress parameters. Sarcoid-derived fibroblasts manifested increased proliferation in vitro, transcriptional rDNA activity (NORs expression) and DNA hypometh...
Extraocular lymphoma in the horse. To describe the clinical findings and prognosis for extraocular lymphoma in the horse. Methods: Retrospective medical records study of horses diagnosed with third eyelid, corneoscleral, conjunctival, and/or eyelid lymphoma from multiple academic and private veterinary institutions. Data collected from the medical records included signalment, clinical descriptions of the extraocular lesions, treatment, and treatment outcomes. Nonparametric statistical analysis was performed with Fischer's exact tests. Results: Extraocular lymphoma involving the eyelid, third eyelid, cornea, sclera, and/...
EcPV-2 is transcriptionally active in equine SCC but only rarely detectable in swabs and semen from healthy horses. Squamous cell carcinomas (SCC) are malignant tumours arising from keratinocytes. In horses, there is increasing evidence for Equus caballus papillomavirus type 2 (EcPV-2) being causally involved in SCC development. However, only little is known regarding intralesional transcription of the virus, and sparse information on the incidence of EcPV-2 infection in healthy equids is available so far. Using RT-PCR, total mRNA from 8 EcPV-2 DNA-positive and 1 EcPV-2 negative SCC/SCC precursor lesions was screened for the presence of EcPV-2 E6 and E1 transcripts. Using PCR, we tested 193 sample specimens...
EcPV2 DNA in equine genital squamous cell carcinomas and normal genital mucosa. Squamous cell carcinoma (SCC) represents the most common genital malignant tumor in horses. Similar to humans, papillomaviruses (PVs) have been proposed as etiological agents and recently Equine papillomavirus type 2 (EcPV2) has been identified in a subset of genital SCCs. The goals of this study were (1) to determine the prevalence of EcPV2 DNA in tissue samples from equine genital SCCs, penile intraepithelial neoplasia (PIN) and penile papillomas, using EcPV2-specific PCR, (2) to examine the prevalence of latent EcPV2 infection in healthy genital mucosa and (3) to determine genetic variabili...
Evaluation of tyrosinase expression in canine and equine melanocytic tumors. To determine the tissue-restricted expression pattern of tyrosinase mRNA in canine and equine melanocytic tumors and relative tyrosinase and major histocompatibility complex (MHC) I mRNA expression in variants of melanocytic tumors. Methods: 39 canine and 8 equine tumor samples and 10 canine and 6 equine normal tissue samples. Methods: RNA was isolated from formalin-fixed, paraffin-embedded tissues. Real-time PCR assays were designed to amplify canine and equine tyrosinase, S18 ribosomal RNA, and major histocompatibility complex I transcripts. Relative expression was determined by use of S18 a...
Cranial mediastinal liposarcoma in a horse. A 23-year-old Anglo-Arabian mare was presented with tachypnea, dyspnea, and pitting edema of the ventral thoracic subcutis. On necropsy, a tan to red, friable, irregularly shaped mass (23 × 20 × 18 cm) occupied the cranial mediastinum. Histologically, the mass was classified as a liposarcoma and was composed of short interlacing bundles of spindle-shaped to irregularly rounded cells with discrete, variably sized, clear cytoplasmic vacuoles, which were stained with oil red O in frozen sections of formalin-fixed tissue.
Computed tomographic appearance of equine sinonasal neoplasia. The computed tomography (CT) features of tumors involving the nasal cavity and/or paranasal sinuses of 15 horses were reviewed. The 15 tumors included five neuroendocrine tumors/neuroblastomas, two undifferentiated carcinomas, two myxosarcomas, and one each of nasal adenocarcinoma, hemangiosarcoma, chondroblastic osteosarcoma, anaplastic sarcoma, myxoma, and ossifying fibroma. All tumors except the ossifying fibroma were iso- or hypoattenuating relative to masseter muscle. Thirteen of the fifteen tumors exhibited moderate or marked osteolysis of adjacent cortical bone and 14/15 were characteri...
Carbon dioxide laser photoablation adjunctive therapy following superficial lamellar keratectomy and bulbar conjunctivectomy for the treatment of corneolimbal squamous cell carcinoma in horses: a review of 24 cases. To determine the complications and nonrecurrence rates following superficial lamellar keratectomy, bulbar conjunctivectomy, and adjunctive carbon dioxide (CO(2)) photoablation for corneolimbal squamous cell carcinoma (SCC) in the horse. Methods: Retrospective study. Sample population Twenty-four horses with corneolimbal SCC. Methods: Medical records of horses diagnosed with corneolimbal SCC that was surgically excised and where CO(2) photoablation was used as an adjunctive therapy from 2000 to 2007 were reviewed. Signalment, prior therapy, tumor location and size, complications,...
Performance characteristics of a conformal ultra-wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non-resectable tumours. Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth...
A retrospective comparison of surgical removal and subsequent CO2 laser ablation versus topical administration of mitomycin C as therapy for equine corneolimbal squamous cell carcinoma. To compare the complications and nonrecurrence rate following topical mitomycin C (MMC) therapy vs. CO(2) laser ablation for treating equine corneolimbal squamous cell carcinoma (SCC). Methods: Retrospective study. Methods: Twenty-five horses with corneolimbal SCC. Methods: Medical records of horses undergoing surgical tumor resection followed by either topical MMC therapy (0.04%) or CO(2) laser ablation between the years of 2004 and 2010 were reviewed. Recurrence and complications were compared between groups and within MMC subgroups defined by the time at which treatment was ...