Sarcoma in horses refers to a group of malignant tumors that arise from connective tissues, including bone, cartilage, fat, muscle, and blood vessels. These tumors can develop in various parts of the horse's body and may differ in their behavior, growth rate, and response to treatment. Common types of sarcomas in horses include fibrosarcoma, osteosarcoma, and hemangiosarcoma. The diagnosis of sarcoma typically involves a combination of clinical examination, imaging techniques, and histopathological analysis. Treatment options may vary depending on the type and location of the tumor and can include surgical excision, chemotherapy, or radiation therapy. This page compiles peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, and treatment of sarcomas in equine patients.
Gumber S, Baia P, Wakamatsu N.A 15-year-old female gray Appaloosa horse was presented with history of a mass over the right dorsal commissure of vulva for the past 7 months. Based on histopathological examination, and positive staining with factor VIII-related antigen, vimentin, and Verhoeff-van Gieson stain, the vulvar mass was diagnosed as hemangiosarcoma with marked solar elastosis.
Arenas-Gamboa AM, Mansell J.Haemangiosarcomas (HSAs) are malignant tumours of endothelial cell origin. Epithelioid HSA is a variant of the histologically conventional HSA that has little or no morphological evidence of a vascular origin and has been reported rarely in domestic animals. The following report documents six cases of equine epithelioid HSA occurring in the ocular tissues of horses with a mean age of 19.8 years at the time of diagnosis. Microscopically, all of the lesions consisted of solid sheets or cords of epithelioid cells with rare narrow clefts or small spaces containing erythrocytes that were often the ...
Yuan Z, Gault EA, Campo MS, Nasir L.Equine sarcoids represent the most common skin tumours in equids worldwide, characterized by localized invasion, rare regression and high recurrence following surgical intervention. Bovine papillomavirus type 1 (BPV-1) and less commonly BPV-2 are now widely recognized as the causative agents of the disease. Fibroblasts isolated from sarcoids are highly invasive. Invasion is associated with a high level of viral gene expression and matrix metalloproteinase upregulation. However, it remains unclear to what extent BPV-1 proteins are involved in the transformation of equine cells. To address this ...
Corteggio A, Di Geronimo O, Roperto S, Roperto F, Borzacchiello G.Studies regarding the functions of the bovine papillomavirus (BPV) E7 oncoprotein in vivo are lacking and no E7-mediated mechanism underlying mesenchymal carcinogenesis is known. Here, we show that the interaction between the 600 kDa retinoblastoma protein-associated factor (p600) and BPV E7, described in vitro in cultured cells, takes place in vivo in naturally occurring equine sarcoids. In these cancers we detect the expression of E7 and p600, and demonstrate that E7 and p600 co-localize and physically interact. Furthermore, intracellular signals involved in p600 functional activity are foun...
Govaere J, Maes S, Saey V, Blancke W, Hoogewijs M, Deschauwer C, Smits K, Roels K, Vercauteren G, de Kruif A.This paper describes a case of uterine fibrosarcoma in an 18-year-old Warmblood mare. The mare had exhibited bloody fluid accumulation inside the uterus and vaginal haemorrhagic discharge since the previous foaling. The mare was euthanized, and on pathological examination, in addition to the uterine neoplasia, multiple metastases were found in the lungs, liver and spleen. The histological and immunohistochemical examination determined that the tumour was a fibrosarcoma. To our knowledge, this is the first paper to describe a uterine fibrosarcoma in a mare.
Snook ER, Wakamatsu N.A 17-year-old, Thoroughbred mare was presented for necropsy with a large, invasive oral mass determined via immunohistochemistry to be a soft tissue sarcoma of neural origin. Oral sarcomas are rare in veterinary medicine, and to the authors' knowledge, this is the first oral sarcoma of neural tissue origin reported in a horse.
Bogaert L, Heerden MV, Cock HE, Martens A, Chiers K.Ten equine skin tumors that had been classified as schwannomas on routine histological examination were analyzed by polymerase chain reaction for bovine papillomavirus DNA. All 10 were positive for bovine papillomavirus 1 or 2, and all 10 were immunohistochemically negative for S-100 protein and strongly positive for vimentin. Nine tumors were moderately positive for laminin and 8, for smooth muscle actin. Five tumors were variably and weakly positive for type IV collagen. The lack of S-100 protein expression made Schwann cells an unlikely cell of origin, as opposed to peripheral nerve sheath ...
Bogaert L, Martens A, Kast WM, Van Marck E, De Cock H.Bovine papillomavirus (BPV)-1 and -2 is linked to equine sarcoids, a commonly observed skin tumor in horses that is of considerable veterinary importance. Previous studies using in situ hybridization have detected BPV DNA only in fibroblasts and not in keratinocytes of sarcoids. In contrast, normal equine skin latently infected with BPV shows a dysplastic epithelium without dermal changes, similar to lesions induced by other papillomavirus types infecting the epithelium. The first goal of our study was to describe the epidermal and dermal characteristics of several stages in sarcoid developmen...
Kannegieter NJ, Schaaf KL, Lovell DK, Simon CD, Stone BM.We describe a fibrosarcoma in a 12-year-old Quarterhorse x Arabian gelding as a sequela to equine influenza vaccination. Shortly after the second vaccination, swelling at the site was noticed by the owner and it continued to increase in size over the following 6 months. Biopsy of the mass indicated a fibrosarcoma had developed at the vaccination site. It was approximately 20 cm in diameter and elevated well above the level of the skin. There was no clinical evidence of metastases to the lungs or local lymph nodes. Surgical resection of the mass was performed and the wound healed by first and s...
Gobeil PA, Yuan Z, Gault EA, Morgan IM, Campo MS, Nasir L.Equine sarcoids are skin tumours of horses caused by infection with BPV-1 or 2. Maintenance and replication of the viral genome depend upon the viral proteins E1 and E2. We examined the effects of an E2 specific siRNA on E2 and E1 viral gene expression, viral load and cell growth in BPV-1 transformed sarcoid-derived cells. Transfection with E2-siRNA caused a reduction in E2 and E1 mRNA expression as well as viral load, growth inhibition and decreased anchorage-independent growth. siRNA treated cells showed significantly higher apoptosis rates than control cells. Thus sequence specific targetin...
Kappe EC, Köhler K, Felbert IV, Teifke JP, Tóth J, Reinacher M.A 14-year-old Haflinger gelding presented with a protruding mass involving the cornea of the right eye. The mass was resected and submitted for histopathologic and immunohistochemical examination. The preliminary diagnosis was corneal sarcoma, most likely fibrosarcoma. The immunohistochemical results confirmed the mesenchymal origin of the neoplastic cells, which were most consistent with a malignant peripheral nerve sheath tumor. Corneal mesenchymal neoplasms are extremely uncommon tumors in human beings and domestic animals. The cause for this tumor was not determined; infection with bovine ...
Equine sarcoids are benign fibroblastic skin tumours that are recognized throughout the world. Infection with bovine papillomavirus (BPV) types 1 and 2 has been implicated as a major factor in disease development; however, the cellular mechanisms underlying fibroblast transformation remain poorly defined. The present study further characterizes aspects of the association with BPV in 15 equine sarcoids. BPV DNA was demonstrated in 12/15 tumours collected from different areas of Italy. Nine of these 12 tumours expressed the BPV oncoproteins E5 and E7, but these oncoproteins were not expressed by...
Brandt S, Haralambus R, Shafti-Keramat S, Steinborn R, Stanek C, Kirnbauer R.Bovine papillomavirus type 1 or 2 (BPV-1, BPV-2) are accepted causal factors in equine sarcoid pathogenesis. Whereas viral genomes are consistently found and expressed within lesions, intact virions have never been detected, thus permissiveness of sarcoids for BPV-1 replication remains unclear. To reassess this issue, an immunocapture PCR (IC/PCR) was established using L1-specific antibodies to capture L1-DNA complexes followed by amplification of the viral genome. Following validation of the assay, 13 sarcoid-bearing horses were evaluated by IC/PCR. Samples were derived from 21 tumours, 4 per...
Puff C, Herder V, Philipp A, Baumgärtner W.A 15-year-old Haflinger gelding presented with a mass in the left nictitating membrane. Two biopsies and the excised nictitating membrane were taken at different time points as a result of reoccurrence of the mass and submitted for histopathologic evaluation. The horse was euthanized as a result of poor prognosis following the reoccurrence of the mass after surgical removal. Histologically, the mass consisted of dilated, thin-walled vascular clefts and channels, lined by flattened to cuboidal endothelial cells with moderate cellular pleomorphism. There was up to 1 mitotic figure per high power...
Théon AP, Wilson WD, Magdesian KG, Pusterla N, Snyder JR, Galuppo LD.To determine outcome associated with cutaneous tumors treated via intratumoral chemotherapy with cisplatin and identify risk factors affecting local tumor control and complications in equidae. Methods: Retrospective case series. Methods: 573 equidae with 630 cutaneous tumors. Methods: Medical records of horses, mules, donkeys, and ponies with cutaneous tumors treated via intratumoral chemotherapy with cisplatin were analyzed. Results: 549 horses, 13 mules, 8 donkeys, and 3 ponies with 630 histologically confirmed cutaneous tumors were included. Tumors included sarcoids (n = 409), squamous cell...
Gearhart PM, Steficek BA, Peteresen-Jones SM.A 12-year-old Belgian draft horse presented for a right eye third eyelid mass and red-tinged ocular discharge of 3 months' duration. The third eyelid was excised and submitted for histopathology. On histopathologic examination, the mass was composed of both hemangiosarcoma and squamous cell carcinoma. The horse developed thickened eyelids and hemorrhagic ocular discharge from the right eye approximately 16 months following surgery, and was euthanized. Necropsy and histopathology confirmed local recurrence and regional metastasis of the hemangiosarcoma. This was an unusual case because there we...
Bush JM, Fredrickson RL, Ehrhart EJ.In horses, osteosarcoma is a rare tumor, with the majority of reported cases occurring in the head, and, more specifically, in the mandible of young horses. The following report documents 8 cases of equine osteosarcoma, the majority occurring in male horses aged 7 years or older with a lack of metastasis identified in any horse. Six arose in the maxilla or mandible and one in the proximal tibia. The predominant subtype was fibroblastic osteosarcoma with fewer osteoblastic type tumors. All had osteoid and most had a chondromucinous matrix. Surgical excision was attempted in the majority of case...
Postey RC, Appleyard GD, Kidney BA.Immunohistochemical (IHC) testing and electron microscopy have implicated Papillomavirus (PV) as the etiologic agent for equine papillomas and aural plaques, but Equine papillomavirus (EPV) DNA has yet to be demonstrated in these lesions by polymerase chain reaction (PCR). The purpose of this study was to evaluate formalin-fixed, paraffin-embedded tissues from naturally occurring cases of equine papillomas, aural plaques, and sarcoids for the presence of EPV DNA by means of PCR and for the presence of PV antigen by means of IHC testing. We used EPV-specific primers that amplified a region of 3...
Hewes CA, Sullins KE.To determine outcome for equids with cutaneous neoplasms treated with cisplatin-containing biodegradable beads, alone or in conjunction with debulking. Methods: Retrospective case series. Methods: 56 horses, 1 zebra, 1 donkey, and 1 mule. Methods: Medical records were reviewed. Follow-up information was obtained through telephone conversations with owners and trainers of the animals. Results: 22 tumors were sarcoids, 6 were fibrosarcomas, 1 was a fibroma, 2 were peripheral nerve sheath tumors, 11 were squamous cell carcinomas, 14 were melanomas (13 gray horses and 1 bay horse), 1 was a lymphos...
Story MR, Gaughan EM, Andrews GA, Balch S.A 14-month-old male Quarter horse was presented for evaluation of a grade 3 out of 5 (grade 0 = sound; grade 5 = non-weight bearing) right rear lameness. A firm, 8 x 16 cm mass was palpable at the caudal medial aspect of the distal tibia and proximal tarsal region of the right hind limb. A percutaneous needle aspirate contained mesenchymal cells that were moderate to large in size with single, oblong nuclei. Differential diagnoses included fibrous hyperplasia, fibroma, or well-differentiated fibrosarcoma. Excisional biopsy for both definitive diagnosis and treatment was offered and selected by...
Ishigami N, Horiba K.A 41-year-old woman presented with symptoms of cardiac tamponade. Diagnosis of a primary malignant tumor in the right atrium without distant metastasis was made by echocardiography, computed tomography and coronary angiography. Aggressive surgery consisting of resection of the tumor including the right atrial wall together with the right coronary artery and sinus node was performed. This was followed by coronary artery bypass grafting with myocardial electrode implantation for reconstruction of the right atrial wall using an equine pericardium. Final diagnosis was of angiosarcoma by pathologic...
Epstein V, Hodge D.Multiple cutaneous lymphosarcomas were diagnosed in an 8-year-old Thoroughbred stallion presented for evaluation of lumps on its scrotum. Histological examination of skin biopsy samples showed a homogenous pattern of lymphoid tissue suggestive of a T-cell lymphosarcoma. Immuno-histochemical tests showed a positive reaction to Rabbit/Anti-Human T-Cell, CD3 antibodies confirming T-cell lymphosarcoma. The animal was not treated and was subsequently euthanased.
Nixon C, Chambers G, Ellsmore V, Campo MS, Burr P, Argyle DJ, Reid SW, Nasir L.Equine sarcoids are benign fibroblastic skin tumours affecting equids worldwide. Whilst the pathogenesis is not entirely understood, infection with Bovine Papillomavirus (BPV) types 1 and 2 has been implicated as a major factor in the disease process, however the mechanism by which BPV infection contributes to sarcoid pathology is not clear. In this study, we show that the majority of sarcoids express the BPV-1 major transforming gene E6. Further, we demonstrate that sarcoid lesions are not associated with high levels of cellular proliferation as assessed by Ki67 expression or with expression ...
Parkinson TJ, Mogg TD, Dykgraaf S, Collett MG.An aged pony gelding presented with sudden onset of neck pain, depression and ataxia and weakness of the hindlegs, together with longer-term weight loss. Diagnostic procedures failed to isolate the cause of these signs and, despite symptomatic treatment, the animal's condition deteriorated until it required euthanasia. Unassigned: Post mortem examination revealed the presence of multiple splenic and hepatic haemangiosarcomata, with metastases to the lung and dorsal cervical muscles overlying C1 and C2 vertebrae. No lesions were present in the spinal cord, spinal column or brain. Conclusions: T...
Hollis AR.Sarcoids are the most common cutaneous neoplasm of the horse, arising as a result of a neoplastic proliferation of fibroblasts associated with infection with bovine papillomavirus, most notably types 1 and 2. Although they do not metastasise, they are locally invasive and aggressive, and can lead to important welfare concerns, interfere with tack and therefore impede athleticism, and undoubtedly lead to a reduction in the value of affected horses. This review discusses the evidence behind the most commonly used treatments for equine sarcoids. The most commonly used treatments are discussed. No...
Miller RI, Campbell RS.A survey of granulomatous and neoplastic diseases of the skin of horses of tropical north Queensland was carried out during the period 1970-1980. Of 338 horses affected, 46.4% suffered from equine fibrosarcoma (sarcoid), 30.2% from phycomycosis, 7.4% from squamous cell carcinoma, 6.8% from other tumours, 4.7% from cutaneous habronemiasis and 4.4% from exuberant granulation tissue. Most specimens were submitted during the first half of the year after the wet monsoonal season and significantly more diseases originated during the first quarter. There was minor variations with breed, age and sex s...
Hainisch EK, Jindra C, Reicher P, Miglinci L, Brodesser DM, Brandt S.Equine sarcoids are common, locally aggressive skin tumors induced by bovine papillomavirus types 1, 2, and possibly 13 (BPV1, BPV2, BPV13). Current in vitro models do not mimic de novo infection. We established primary fibroblasts from horse skin and succeeded in infecting these cells with native BPV1 and BPV2 virions. Subsequent cell characterization was carried out by cell culture, immunological, and molecular biological techniques. Infection of fibroblasts with serial 10-fold virion dilutions (2 × 10-20 virions) uniformly led to DNA loads settling at around 150 copies/cell after four pass...
Podstawski P, Samiec M, Skrzyszowska M, Szmatoła T, Semik-Gurgul E, Ropka-Molik K.The equine sarcoid is one of the most common neoplasias in the family. Despite the association of this tumor with the presence of bovine papillomavirus (BPV), the molecular mechanism of this lesion has not been fully understood. The transgenization of equine adult cutaneous fibroblast cells (ACFCs) was accomplished by nucleofection, followed by detection of molecular modifications using high-throughput NGS transcriptome sequencing. The results of the present study confirm that - and -mediated nucleofection strategy significantly affected the transcriptomic alterations, leading to sarcoid-like...
Kannegieter NJ, Alley MR.A 20-month-old, Standard-bred colt was presented with an acute onset of hindlimb ataxia. Clinical and radiographic examination identified a compressive lesion affecting the spinal cord at the level of the 17th to 18th thoracic vertebrae. After euthanasia, post-mortem examination revealed a tumour in the epidural space, diagnosed histologically as a lymphosarcoma. Neoplastic lymphoid cells were also present in the abdominal lymph nodes and brain. Because of the disseminated nature of lymphosarcoma in the horse, involvement of the central nervous system is likely to be more common than is presen...
Okada K, Okada M, Yamamoto S, Mukai T, Tsukube T, Matsuda H, Okada M.We successfully performed a total resection of the pulmonary artery trunk and replaced it with an equine pericardial xenograft roll in a patient with a recurrent leiomyosarcoma. We believe, based on anatomic and embryologic principles, total rather than partial resection of the pulmonary artery trunk should be the treatment of choice for primary leiomyosarcomas of the pulmonary artery.
Gumber S, Baia P, Wakamatsu N.A 15-year-old female gray Appaloosa horse was presented with history of a mass over the right dorsal commissure of vulva for the past 7 months. Based on histopathological examination, and positive staining with factor VIII-related antigen, vimentin, and Verhoeff-van Gieson stain, the vulvar mass was diagnosed as hemangiosarcoma with marked solar elastosis.
Bush JM, Fredrickson RL, Ehrhart EJ.In horses, osteosarcoma is a rare tumor, with the majority of reported cases occurring in the head, and, more specifically, in the mandible of young horses. The following report documents 8 cases of equine osteosarcoma, the majority occurring in male horses aged 7 years or older with a lack of metastasis identified in any horse. Six arose in the maxilla or mandible and one in the proximal tibia. The predominant subtype was fibroblastic osteosarcoma with fewer osteoblastic type tumors. All had osteoid and most had a chondromucinous matrix. Surgical excision was attempted in the majority of case...
Gerding JC, Gilger BC, Montgomery SA, Clode AB.A 7-year-old, 153.0-kg American Miniature mare presented for evaluation of keratoconjunctivitis of the right eye (OD). A superior palpebral conjunctival mass and stromal keratitis were diagnosed. The incisional biopsy diagnosis was a presumptive corneal hemangiosarcoma. Transpalpebral enucleation was performed, and histopathologic evaluation confirmed angiosarcoma of the conjunctiva, cornea, and extraocular muscles. The horse developed progressive epistaxis and orbital swelling following surgery. A systemic workup was performed 3 months after enucleation, revealing regrowth within the orbit an...
Carmalt JL, Linn KA.To describe a large segmental (sub-total) mandibulectomy for removal of an undifferentiated sarcoma in a horse. Methods: Clinical report. Methods: A 10-year-old mare. Methods: A combination of methods including computed tomography (CT) were used to diagnose a large undifferentiated sarcoma of the right mandible. A large segmental mandibulectomy extending from 3 cm below the right temporomandibular joint to immediately caudal to tooth 407 was used to perform an en-bloc resection of the mass under general anesthesia. Results: Surgery time was 11 hours and 35 minutes and total anesthesia time, 12...
Spugnini EP, Bolaffio C, Scacco L, Baldi A.An eleven-year-old stallion was referred for adjuvant treatment of an incompletely excised, recurring penile fibrosarcoma. The horse was bright, alert and responsive with a 15 x 12 cm ulcerated lesion on the ventral side of the penis. The lesion was the tumor bed of an incompletely excised fibrosarcoma. After complete staging procedures, the owner elected to treat the horse with electrochemotherapy (ECT) using cisplatin as chemotherapy agent. Two sessions of ECT were performed at two-week intervals using local cisplatin followed by trains of biphasic electric pulses applied using different ele...
Sanchez B, Nieto A, de Ruiz Leon MA, Rodríguez J, Flores J.A lymphangiosarcoma with metastases was found in a horse that presented with respiratory distress and edema in the ventral thorax and abdomen. The necropsy revealed diffuse edema in the subcutaneous connective tissue. Mediastinal, mesenteric, iliac, and renal lymph nodes were enlarged and white with soft, yellowish necrotic areas. Histologic examination revealed numerous channels and disorganized vessels lined by large polyhedral, polymorphic cells. Tumor metastases were observed in the spleen, lungs, and kidneys. Immunohistochemical evaluation of the tumor cells demonstrated positive staining...
Gysens L, Martens A, Haspeslagh M.Although bovine papillomavirus (BPV)-induced equine sarcoids are often identified solely by clinical examination, confirmation of the clinical diagnosis is essential for correct treatment selection. Only few approaches are presently available for this purpose. PCR-based screening for BPV in superficial swabs is widely-used to support clinical suspicion. While this method effectively detects sarcoid involvement in ulcerated lesions, sensitivity is lower in tumors with intact epithelium. This cross-sectional study compared the diagnostic characteristics of superficial swabs and fine-needle aspir...
van den Hoven R, Franken P.This paper describes the clinical and laboratory findings in 16 horses suffering from lymphosarcoma and the autopsy results in 13 of these cases which were examined at the Large Animal Medicine Clinic, State University of Utrecht, from 1969 to 1981. The cases were classified into four groups, designated multicentric, alimentary, thymic and cutaneous forms, according to the situation of the tumours.
Hanson PD, Frisbie DD, Dubielzig RR, Markel MD.A 5-year-old Quarter Horse mare was examined because of a 6-month history of quidding and nasal discharge that contained feed material. Physical examination revealed weight loss and dorsal displacement of the soft palate, caused by a soft tissue mass located at the dorsal aspect of the base of the tongue. Surgical resection of the mass was successfully performed through an oral approach. The histopathologic diagnosis was rhabdomyosarcoma.
Beaumier A, Dixon CE, Robinson N, Rush JE, Bedenice D.Cardiac hemangiosarcoma, especially primary, is infrequently reported in the horse and remains a diagnostic challenge because of vague clinical signs and difficulty to reach an antemortem diagnosis. A 17-year-old American Quarter Horse gelding was presented with a history of tongue swelling and secondary aspiration pneumonia. Initial assessment indicated dehydration, and thoracic ultrasound revealed an abnormal structure within the myocardium alongside the previously suspected aspiration pneumonia. A subsequent, complete echocardiogram identified a large, heterogeneous, ill-defined mass invadi...
Hilmas DE, Gillette EL.The clinical records and follow-up data obtained over 13 years on the results of radiotherapy of spontaneous fibrous connective-tissue sarcomas in dogs, cats, and horses were reviewed. The results obtained from the treatment of fibrosarcomas and sarcoids of horses indicated that radiation administered with 60Co is important in the medical and surgical management of these tumors. Fibrous connective-tissue sarcomas in horses were radioresponsive. When radiotherapy was applied postoperatively, the probability of a 2-year cure approached 50% for all prescribed radiation doses of less than 2,000 to...
Hacker DV, Moore PF, Buyukmihci NC.In 4 horses with ocular angiosarcomas, the common characteristics were that all horses were aged, and the neoplasms developed initially on conjunctival surfaces, grew slowly, and metastasized despite excision and radiation treatment. Histopathologically, the neoplasms were of 2 types: a capillary pattern of scant stroma and endothelial-lined vascular channels, and a solid pattern composed of sheets of pleomorphic cells with hyperchromatic nuclei and poorly defined cytoplasmic borders. Definitive diagnosis was made by use of factor VIII:RAg, which stained the tissues intensely.
Gearhart PM, Steficek BA, Peteresen-Jones SM.A 12-year-old Belgian draft horse presented for a right eye third eyelid mass and red-tinged ocular discharge of 3 months' duration. The third eyelid was excised and submitted for histopathology. On histopathologic examination, the mass was composed of both hemangiosarcoma and squamous cell carcinoma. The horse developed thickened eyelids and hemorrhagic ocular discharge from the right eye approximately 16 months following surgery, and was euthanized. Necropsy and histopathology confirmed local recurrence and regional metastasis of the hemangiosarcoma. This was an unusual case because there we...
Anderson WI, Scott DW, Crameri FM.Two rare equine cutaneous neoplasms, an apocrine gland adenocarcinoma and a carcinosarcoma were diagnosed in a 17-year-old pony and a 14-year-old mare, respectively. The apocrine gland adenocarcinoma was present on the prepuce. Histologically, papillary projections of low cuboidal to columnar epithelial cells were generally well differentiated, and surrounded dilated acini. Stromal invasion was present, but vascular and lymphatic invasion was not seen. The carcinosarcoma was present in the right flank of the mare. Two discrete cell populations were characterized histologically. One portion of ...
Cheevers WP, Fatemi-Nainie S, Anderson LW.A retrovirus is spontaneously released into the culture medium of the equine sarcoid-derived MC-1 cell line. The MC-1 virus did not exhibit in vitro transforming activity or replication when tested on equine fibroblasts or a variety of other mammalian cell cultures. Complementary DNA, synthesized using detergent-activated MC-1 virus RNA-dependent DNA polymerase, detected homologous sequences in the DNA of an established equine dermal cell line and in the DNA of primary equine dermal fibroblasts. Iododeoxyuridine or azacytidine induced a replication-deficient endogenous retrovirus in the normal...
Sweeney CR, Gillette DM.Thirty-two horses and 3 ponies had neoplasia involving the thoracic cavity. Lymphosarcoma of the thorax was found in 19 (54.2%) of the equids. The other 16 equids had metastatic adenocarcinoma (7 horses; 20%), metastatic squamous cell carcinoma (5 equids; 14.3%), metastatic hemangiosarcoma (3 equids; 8.6%) or undifferentiated sarcoma (1 horse; 2.9%). Thoracic neoplasia was diagnosed before death in 15 equids (42.9%).
Edens LM, Taylor DD, Murray MJ, Spurlock GH, Anver MR.A large fibrotic mass originating from the cecal base was discovered upon surgical exploration of the abdomen in a Thoroughbred mare with a history of chronic colic and weight loss. The mass protruded intraluminally resulting in partial obstruction. Surgical excision was not feasible due to the location of the mass and the inability to exteriorize it adequately from the abdominal cavity. The mass was fibrous with a shiny, gelatinous material present throughout the neoplasm. Histologically, large confluent spaces filled with mucopolysaccharides were identified by staining with Alcian blue. The ...
Gobeil PA, Yuan Z, Gault EA, Morgan IM, Campo MS, Nasir L.Equine sarcoids are skin tumours of horses caused by infection with BPV-1 or 2. Maintenance and replication of the viral genome depend upon the viral proteins E1 and E2. We examined the effects of an E2 specific siRNA on E2 and E1 viral gene expression, viral load and cell growth in BPV-1 transformed sarcoid-derived cells. Transfection with E2-siRNA caused a reduction in E2 and E1 mRNA expression as well as viral load, growth inhibition and decreased anchorage-independent growth. siRNA treated cells showed significantly higher apoptosis rates than control cells. Thus sequence specific targetin...
Bolton JR, Lees MJ, Robinson WF, Thomas JB, Klein KT.HAENIANGIOMAS and haemangiosarcomas are neoplasms of probable vascular origin that occur rarely in the equine eye in a survey there were 21 cases of vascular neoplasia in the skin of horses, and the prevalence of these two tumours was estimated to be 0.25 and 0.02 percent respectively (Hargis and McElwain 1984). Their incidence is likely to be less in the eye than in the skin and in two surveys of equine ocular tumours there is only brief mention of two hacnumgiasarcomas. one involving the lid (Morgan 1969), the other the orbit and lower eyelid (Lavach and Severin 1977). Only two cases of hacm...
