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.
Cannabidiol-induced cellular and matrix-associated responses in primary equine sarcoid cells. Sarcoids are locally invasive skin tumors in equids, associated with bovine papillomavirus. Objective: Address potential applications of cannabidiol (CBD) in veterinary medicine. We evaluated the response of equine sarcoid cells to CBD in vitro, focusing on viability, invasiveness, and matrix remodeling. Methods: Three primary sarcoid cell lines. Methods: Cells were treated with CBD (20, 6.75, 2.25, 0.75 μM) and incubated for 6, 24, 48, 72 hours. Cell viability, cytotoxicity, and apoptosis were assessed using the ApoTox-Glo Assay. Based on these results, further analyses were performed for ...
Acquired and Degenerative Conditions of the Cervical Vertebral Column in Horses. The cervical vertebral column in horses plays a crucial role in movement, posture, and performance and disorders affecting it can cause pain, ataxia, or lameness. This review discusses major acquired (traumatic, infectious, neoplastic) and degenerative (osteoarthritis, foraminal stenosis, intervertebral disc disease) conditions. Acquired lesions often arise from trauma, bacterial infection, or neoplasia, with clinical signs ranging from neck pain to neurologic deficits. Degenerative disorders, particularly osteoarthritis of articular process joints, are common in the caudal cervical spine and ...
Engineered biopolymeric hydrogels for in vitro modeling of equine sarcoid tumors in comparative oncology. Developing advanced preclinical in vitro cancer models is essential for understanding tumor biology, improving drug discovery, and enhancing the clinical translation of new therapies. Papillomaviruses (PVs) cause diverse lesions in humans and animals; notably, bovine papillomavirus (BPV) is the main cause of equine sarcoid, the most common skin tumor in horses. Its pathogenesis involves viral infection, fibroblast transformation, and extracellular matrix (ECM) remodeling. These processes highlight the limitations of conventional two-dimensional (2D) culture systems, which fail to replicate the...
Clear cell squamous cell carcinoma in the third eyelid of a horse. Squamous cell carcinoma (SCC) is the most common ocular and periocular neoplasm of horses, typically arising from the limbus, third eyelid mucosa or mucocutaneous junctions of the upper and lower eyelids. Tumours are locally invasive, prone to recurrence and may rarely metastasize. Histological evaluation is required for definitive diagnosis and atypical SCC subtypes may be diagnostically challenging. Here we describe a clear cell SCC in the third eyelid of a 16-year-old female Quarter Horse. The red and invasive mass was surgically excised for histological evaluation. The lesion consisted of ...
Two cases of primary hepatic neoplasia in young horses: Diagnostic challenges and clinical implications. Primary hepatic neoplasms are rare in horses and often have a poor prognosis due to non-specific clinical signs and delayed diagnosis. This report describes two cases of primary hepatic neoplasia in young horses. The first case was a yearling Hanoverian filly presenting with non-specific clinical signs, including poor weight gain and inappetence, ultimately diagnosed with hepatoblastoma based on ultrasonographic findings and histopathological examination. The second case was a three-year-old Polish Sport Horse stallion that died suddenly, with post-mortem examination revealing advanced cholang...
Reducing Recurrence in Equine Corneolimbal SCC: Outcomes of Adjunctive Cisplatin Biodegradable Bead Therapy. (1) Context: Squamous cell carcinoma (SCC) is the most prevalent ocular neoplasm in horses, with a reported 45% recurrence rate when managed by surgery alone. (2) Objective: To evaluate the effect of adjunctive cisplatin biodegradable beads (CBBs) on recurrence rates of equine corneolimbal squamous cell carcinoma (SCC) and to document associated adverse effects. (3) Methods: Seventeen cases of histopathologically confirmed corneolimbal SCC in horses were retrospectively identified. Masses were surgically excised by keratectomy and/or conjunctivectomy under general anesthesia, followed by impla...
Detection of vasculogenic mimicry in equine ocular, oronasal, and genital squamous cell carcinoma. Squamous cell carcinoma (SCC) is the most common malignant tumor disease in horses. It predominantly affects the ocular, oronasal, and anogenital region. Equine SCC is difficult to treat, also because important aspects of SCC development and metastasis are still unclear. We previously provided evidence that equine SCC cells can adopt a stem cell-like phenotype as a hallmark of malignant progression. Here, we investigated whether equine SCCs harbor endothelial-like tumor cells that form an alternative network of pseudo-vessels better known as vasculogenic mimicry (VM). Following histopathologic...
Melanoma in horses: distribution by sex, age, nationality, and slaughterhouse findings in 28 horses from Northern Italy. Melanomas are dermal-epidermal and subcutaneous tumors commonly found in horses, especially those with grey coats. This study aimed to characterize melanomas in slaughtered horses by analyzing their distribution according to sex, age, and nationality, and to describe the veterinary inspection interventions required at slaughterhouses based on lymph node involvement and distant metastases in a province of northern Italy. Between January and December 2024, 182 grey horses were examined, and 28 cases of melanoma were identified (15% of grey horses) with an average age of 14 years: 8 males (mean a...
Intraocular Tumors in Horses: Diagnosis, Tumor Classification, Oncologic Assessment and Therapy. Intraocular neoplasia in horses is rare and only few case reports and small case series exist. Intraocular neoplasia has various clinical signs and includes important differential diagnoses in ocular disease. This narrative review of the current literature aims to provide a clinically relevant overview and classification of intraocular tumors in horses and adds a comparative oncological perspective concerning diagnosis, treatment and future considerations. The available clinical and imaging examination techniques allow for a reliable and differentiated investigation of the tumor, even in the s...
Corneal Squamous Cell Carcinoma Arising From a Conjunctival Graft Scar in a Horse. To describe the case details of an equine corneal squamous cell carcinoma (SCC) arising from the central scar of a previous conjunctival pedicle graft. Methods: An 18-year-old Thoroughbred gelding, showing a progressive increase in diameter, depth, opacity, and pigmentation of a conjunctival pedicle graft scar of the left eye, 34 months after surgery. Methods: Complete ophthalmic examination, standard histologic and immunohistochemical evaluation of an incisional biopsy to formulate a definitive diagnosis. Carbon dioxide (CO) laser photoablation combined with topical mitomycin C treatment. R...
Autologous Cancer Vaccines: A Precision Immunotherapy Strategy for Veterinary Cancer Patients. Precision medicine is a therapeutic strategy to provide treatment that is tailored to a specific patient based on factors unique to that individual, such as the genetic makeup or the environment. Autologous cancer vaccines (ACVs) are ideal for a precision medicine approach because they incorporate antigens specific to the patient's tumor and provide an elegant solution to identifying and selecting relevant immunogenic neoantigens. ACVs are an appealing option for veterinary medicine because they are cancer-type and species agnostic. Over the past 50 years, many innovative ACVs have been evalua...
Probing Wnt pathway and functional signal in equine melanocytic neoplasms through quantitative proteomics and immunohistochemistry. Equine melanocytic neoplasm (EMN) is a skin tumor commonly observed in grey horses. Limited research has yet to investigate proteomic profiles of EMN, particularly in the early stages and their expression patterns. This study, therefore, aimed to identify signature proteins from tissue biopsies to distinguish early EMN, severe EMN, and normal groups. Results: Using proteomic analysis of 19 tissue samples (normal: n = 6, early EMN: n = 7, severe EMN: n = 6) through LC-MS/MS, 12,310 proteins were identified. Differentially expressed proteins (DEPs) and functional interaction analysi...
Pigments with antimicrobial and cytotoxic activities from the coprophilous fungus Fusarium solani isolated from horse dung. Four previously undescribed phenazine-derived pigments (1-4), along with seventeen known compounds, were isolated from a strain cultured on solid rice medium. Structural elucidation of the new compounds was achieved through extensive spectroscopic analysis, while known compounds were identified by comparison with literature data. The antimicrobial and cytotoxic activities of the isolated compounds were assessed. Compounds 2, 5, and 11 exhibited weak antifungal activity against at 200 μM, while compounds 5, 6, 11, 12, 15, and 20 demonstrated moderate antibacterial effects against at the sam...
Gray-Horse Melanoma-A Wolf in Sheep’s Clothing. Malignant melanoma (MM) affects not only humans but also animals, with gray horses being particularly predisposed to acquiring the disease. Multiomics have greatly advanced the understanding of human MM. In contrasty little is known regarding the pathogenesis of gray-horse melanoma and the unique phenomenon of melanoma "dormancy" in some animals. To help close this gap in knowledge, melanoma tissue and intact skin collected from gray horses were subjected to transcriptome analysis using RNAseq. In the next step, cultured primary tumor cells and normal skin fibroblasts were established from gra...
Immune cell analysis in equine penile papilloma, in situ squamous cell carcinoma and invasive squamous cell carcinoma: FoxP3+ T regulatory lymphocytes differ according to equine papillomavirus 2 status. Equine penile tumors are common in horses and are often related to infection with equine papillomavirus type 2 (EcPV2). This study investigated the immune cell infiltrate (ICI) of these tumors in horses, focusing on the role of EcPV2. Using multiplex immunohistochemistry (mIHC) for CD3, CD20, and IBA-1 and immunohistochemistry (IHC) for FoxP3, 27 horses with papillomas (5/27), in situ carcinomas (CISs) (3/27), and squamous cell carcinomas (SCCs) (19/27) were evaluated. Eighteen cases tested positive for EcPV2 by either or both in situ hybridization (ISH) and polymerase chain reaction (PCR) (18...
Altered expression of collagen gene family members and its epigenetic background in equine Sarcoids. Alterations in the genes involved in the creation of the extracellular matrix (ECM) were observed in our earlier transcriptome studies of sarcoids and their cell culture model. For a complete characterization of the underlying molecular pathways, it is imperative to comprehend the involvement of ECM modifications in the oncogenic transformation of sarcoid fibroblasts. Thus, the aim of this investigation was to describe the expression patterns of a set of genes that are essential for the rearrangements of the extracellular matrix, namely collagen genes, and elucidate possible mechanisms underly...
Intratumoural tigilanol tiglate in the multicentre treatment of equine sarcoids and cutaneous melanomas. Intralesional chemotherapeutic administration represents an important treatment option for equine cutaneous neoplasia. Tigilanol-tiglate (TT), a novel molecule extracted from Fontainea picrosperma, an Australian rainforest plant, is registered for intratumoural treatment of canine MCT, leading to rapid oncosis and tumour slough. Evidence from horses is limited but suggests that efficacy may be similar. Objective: To evaluate the response to intratumoural TT treatment in horses with sarcoids (fibroblastic/nodular) and cutaneous melanomas. Methods: Two noncontrolled prospective multicentre clini...
Papillary Renal Cell Carcinoma With Widespread Metastases in an Arabian Mare. This report describes a case of massive renal cell carcinoma (RCC) causing mild chronic colic in a 20-day-postpartum Arabian mare. The mare presented with deteriorating abdominal pain following normal parturition. Clinical examination revealed tachycardia, tachypnoea, weak intestinal motility and pale mucosal membranes. Rectal examination identified a very large mass in the caudal part of the abdominal cavity, and abdominal ultrasound examination revealed a huge space-occupying mass with renal architecture. During midline exploratory laparotomy, a massive tumour was observed in the anatomical ...
Studying the Impact of the DDB2 T338M Missense Mutation on the Development of Equine Squamous Cell Carcinoma and Sarcoid. A missense mutation in damage-specific DNA binding protein 2 (DDB2 c.1013 C>T; p.Thr338Met) has been described as a risk factor for ocular squamous cell carcinoma (OSCC) in the Haflinger breed. Here, we examined the impact of DDB2 C>T allele status on the development of OSCC, squamous cell carcinoma (SCC) at other localisations, or equine sarcoid (ES) in Haflingers and other breeds with a high incidence of these tumour types. We genotyped affected Haflinger, Noriker, Warmblood, and Icelandic horses. Results based on 56 Haflingers confirmed the significantly higher risk for OSCC in DDB2-TT Hafl...
Electrochemotherapy with bleomycin for bilateral ocular squamous cell carcinoma in a horse. To describe the procedure and outcome of electrochemotherapy (ECT) with bleomycin as a first-line treatment for bilateral ocular surface squamous neoplasia (OSSN) in the eye of a horse. Methods: A client-owned 5-year-old Haflinger gelding with limbal-conjunctival squamous cell carcinoma. Methods: During general and local anesthesia, injection of bleomycin in the ocular tumor was followed by electroporation, applied with a 15 mm needle electrode, needles held parallel to the ocular surface. Results: Treatment with ECT resulted in therapeutic electric pulses and complete tumor response with no...
Electrochemotherapy with bleomycin for bilateral ocular squamous cell carcinoma in a horse. To describe the procedure and outcome of electrochemotherapy (ECT) with bleomycin as a first-line treatment for bilateral ocular surface squamous neoplasia (OSSN) in the eye of a horse. Methods: A client-owned 5-year-old Haflinger gelding with limbal-conjunctival squamous cell carcinoma. Methods: During general and local anesthesia, injection of bleomycin in the ocular tumor was followed by electroporation, applied with a 15 mm needle electrode, needles held parallel to the ocular surface. Results: Treatment with ECT resulted in therapeutic electric pulses and complete tumor response with no...
[Retrospective study of the effectiveness of human tyrosinase vaccination in eight horses]. Dermal melanoma is a common neoplastic disease in horses, which occurs particularly in gray horses. There are various local and systemic therapeutic approaches to treat this skin tumor. Vaccination with human tyrosinase, ONCEPT ® vaccine, is a newer type of systemic melanoma therapy. In this study, the effectiveness of this ONCEPT ® vaccine was retrospectively examined in eight treated horses. In half of the horses (4) a positive change in tumor growth in the sense of retardation, stagnation and, in one of these horses, even reduction in the size of the melanomas was observed. Of the rem...
Overexpression of the key metabolic protein Carnitine Palmitoyl Transferase 1A (CPT1A) in equine sarcoid. The equine sarcoid is the most common skin neoplasia of fibroblastic origin in horses, characterized by an excessive accumulation of extracellular matrix produced by sarcoid fibroblasts under hypoxic condition. Neoplastic cells can adapt to hypoxia by using alternative energy sources, particularly those that arise from fatty acid oxidation (FAO). The Carnitine Palmitoyl Transferase 1A (CPT1A) belongs to Carnitine System (CS) and promotes the entrance of fatty acids into the mitochondria for β-oxidation. In this study, CPT1A expression was comparatively addressed in 25 equine sarcoids and 5 no...
Multimodal Spatial Profiling Reveals Immune Suppression and Microenvironment Remodeling in Fallopian Tube Precursors to High-Grade Serous Ovarian Carcinoma. High-Grade Serous Ovarian Cancer (HGSOC) originates from fallopian tube (FT) precursors. However, the molecular changes that occur as precancerous lesions progress to HGSOC are not well understood. To address this, we integrated high-plex imaging and spatial transcriptomics to analyze human tissue samples at different stages of HGSOC development, including p53 signatures, serous tubal intraepithelial carcinomas (STIC), and invasive HGSOC. Our findings reveal immune modulating mechanisms within precursor epithelium, characterized by chromosomal instability, persistent interferon (IFN) signaling...
Disseminated pleomorphic rhabdomyosarcoma in a horse. An 8-y-old National Show Horse mare was presented for evaluation of pneumonia and laminitis. Harsh bronchovesicular sounds were auscultated throughout both lung fields, and the mare had signs of moderately painful laminitis. Thoracic ultrasonography revealed lung consolidation throughout the dorsal aspect of both lungs, and radiography revealed an extensive diffuse-to-patchy bronchointerstitial lung pattern. The mare's clinical condition rapidly deteriorated, and euthanasia was elected. On postmortem examination, the lungs, omentum, spleen, liver, adrenal glands, kidneys, and femur contained 0...
Equine Melanoma Updates. Melanomas are very common in older gray horses, with 80% of gray horses having at least 1 melanoma by 15 years of age. Historically considered a benign disease, it is now known that up to 66% of lesions will eventually metastasize. Melanomas may also cause local problems due to abscessation, ulceration, and interference with function of the affected areas. Treatment can be limited by size and location, but surgical resection, where possible, is likely to be the treatment of choice.
Diagnosis and Staging of Equine Neoplasia. The diagnosis of neoplasia in the horse is both simple and extremely challenging, depending on the type of neoplasm and its location. Obtaining an accurate diagnosis of a neoplastic condition is key to formulating an appropriate treatment plan if possible or developing a palliative plan if curative treatment options do not exist. A combination of historical features, clinical examination findings, and diagnostic testing typically allow a working diagnosis of neoplasia to be made, with a definitive diagnosis requiring the identification of neoplastic cells in a sample or tissue.
An intronic copy number variation in Syntaxin 17 determines speed of greying and melanoma incidence in Grey horses. The Greying with age phenotype in horses involves loss of hair pigmentation whereas skin pigmentation is not reduced, and a predisposition to melanoma. The causal mutation was initially reported as a duplication of a 4.6 kb intronic sequence in Syntaxin 17. The speed of greying varies considerably among Grey horses. Here we demonstrate the presence of two different Grey alleles, G2 carrying two tandem copies of the duplicated sequence and G3 carrying three. The latter is by far the most common allele, probably due to strong selection for the striking white phenotype. Our results reveal a rem...
Exploring the Dissolution, Solid-state Properties, and Long-term Storage Stability of Cryoprotectant-free Fenbendazole Nanoparticles. Fenbendazole is an antiparasitic drug widely used in veterinary medicine to treat parasitic infections caused in animals like cattle, horses, sheep, and dogs. Recently, it has been repositioned as a potential alternative for cancer treatment. However, it is a highly hydrophobic molecule (0.9 ug/mL), which can compromise its dissolution rate and absorption. Thus, this work aimed to apply a nanotechnological approach to improve drug solubility and dissolution performance. Fenbendazole nanoparticles stabilized by different poloxamers were obtained by lyophilization without cryoprotectants. The be...
Radiotherapy in Equine Practice. Radiotherapy is a valuable treatment option for equine tumors that have a high rate of recurrence or where complete surgical resection may damage vital structures. Teletherapy, brachytherapy, and plesiotherapy have been used successfully for the treatment of a variety of tumors and locations in the horse. Radiobiology, treatment protocols, side effects, and patient management are reviewed, with a focus on linear accelerator-based teletherapy. There is evidence of good success rates for treatment of periocular sarcoids and squamous cell carcinoma but teletherapy treatment is often limited to tu...