Tumors in horses are abnormal growths of tissue that result from uncontrolled cell division. They can be benign or malignant and may affect various tissues and organs within the equine body. Common types of tumors in horses include sarcoids, melanomas, and squamous cell carcinomas. The presence and progression of tumors can impact a horse's health, performance, and quality of life. Diagnosis often involves clinical examination, imaging techniques, and histopathological analysis. This page compiles peer-reviewed research studies and scholarly articles that explore the types, diagnosis, treatment options, and prognostic factors associated with tumors in equine medicine.
van Rensburg IB, Stadler P, Soley J.A bronchiolo-alveolar adenocarcinoma was diagnosed in the lungs of a horse which was euthanased after protracted respiratory disease and radiological evidence of pulmonary neoplasia. Multifocal, large, firm neoplasms occurred throughout both lungs. Neoplastic lesions were not found elsewhere. Histologically the bronchiolar and alveolar architecture was retained. The cuboidal cells lining neoplastic alveoli had very vacuolated cytoplasm, while some were ciliated. Electron microscopy identified the cells as Type II pneumocytes. Numerous distended myelinoid bodies in the tumour cells accounted fo...
Palmer SE.A verrucous sarcoid was removed from the ear of a horse, using a carbon dioxide laser. The use of carbon dioxide laser excision and ablation enabled complete removal of tumor cells, with minimal damage to underlying normal cartilage. Cosmetic healing was observed with minimal disfigurement. Recurrence of the tumor was not observed after 11 months.
Smith BL, Morton LD, Watkins JP, Taylor TS, Storts RW.A 16-year-old cryptorchid Quarter House with colic had a large, lobulated soft-tissue mass to the left of the pelvic inlet. At surgery, 2 large multilobulated pedunculated masses were removed. A large blood vessel enveloped by one of the masses was damaged, and the horse exsanguinated. Postmortem examination of the abdomen revealed the masses to be malignant seminoma, with multiple sites of metastasis.
Detilleux PG, Cheville NF, Sheahan BJ.Tissues from subcutaneous lymphosarcomas and regional lymph nodes were examined by light and electron microscopy and by lectin histochemistry. Tumors were composed of two major cell types: small lymphocytes with few organelles and pleomorphic histiocytic cells with undulant surfaces, large numbers of cytoplasmic vacuoles, and many mitochondria with large crystalline inclusions. A large gram-positive coryneform bacterium was isolated from tumor nodules but was not identified morphologically in tumor tissues. Evaluation of sections of tumors with lectins as histochemical probes revealed three st...
Van Camp SD, Mahler J, Roberts MC, Tate LP, Whitacre MD.An ovarian adenocarcinoma with teratomatous elements was removed from a 9-year-old mare. Although no other lesions were detected at ovariectomy, multifocal metastatic masses led to cachexia and euthanasia 2 months later. This case reaffirms the need to exercise caution when removing ovarian masses to prevent seeding of the abdomen. This report includes discussion of the WHO system of classification of ovarian tumors.
Hill FW, Moulton JE, Schiff PH.A fifteen-year-old thoroughbred gelding with exophthalmos of the left eye, was found at necropsy to have an adenocarcinoma of the left frontal sinus. The tumour extended caudally through the cribriform plate into the orbit, displacing the eyeball anteriorly.
Madewell BR, Munn RJ.Abnormal irregularly branched and anastomosing tubules within cisternae of endoplasmic reticulum were observed by transmission electron microscopy in tumour cells comprising connective tissue neoplasms (sarcoids) from three horses and a mule. These tubuloreticular inclusions were also observed in cultured tumour cells from one of these horses examined, but were not detected in fibroblasts (fibrocytes), epidermis, or vascular endothelial cells in skin biopsy specimens from five clinically healthy horses, nor in one additional equine connective tissue neoplasm.
Hamir AN.During a routine necropsy examination of a 4-year-old standardbred mare, a well-demarcated dermal mass was seen near the right elbow. Grossly, the mass consisted of multifocal variably sized areas of dark brown, firm material that was separated by thin white septa. Histologically, within the individual compartments, there were numerous multinucleated giant cells, macrophages, and free erythrocytes. A diagnosis of giant cell tumor of soft tissues was made.
Allen D, Swayne D, Belknap JK.The clinical signs, medical and surgical management, and pathological findings are described for a ganglioneuroma, an atypical intestinal tumor, that caused colic because of small intestinal obturation.
Wilson DA, Foreman JH, Boero MJ, Didier PJ, Lerner DJ.A large granulosa cell tumor was believed to be responsible for causing obstruction and subsequent rupture of the small colon in a 10-year-old Quarter Horse mare. Two months earlier, a mass, tentatively diagnosed as granulosa cell tumor of the left ovary, had been identified by means of rectal palpation and ultrasonography. The mare was evaluated for clinical signs of acute, severe, abdominal pain, increased heart rate, cyanotic mucous membranes, clinical dehydration, with high PCV, leukopenia, and extreme abdominal distension. A large soft tissue mass and taut band that constricted the lumen ...
Green SL, Specht TE, Dowling SC, Nixon AJ, Wilson JH, Carrick JB.A neonatal foal was examined because of apparent abdominal pain and distention, anemia, and hemoperitoneum. Exploratory laparotomy was performed, and a large spherical mass, which had ruptured, was found in the area of the left ovary. Left salpingo-oophorectomy was performed. The mass was determined to be a juvenile granulosa cell tumor.
Morse CC, Saik JE, Richardson DW, Fetter AW.Benign proliferative fibro-osseous lesions of the rostral mandible in six young horses are classified as equine juvenile mandibular ossifying fibroma. Histologically there is a characteristic abrupt transition from subgingival fibroblastic stroma to a zone of proliferating osteoblasts that form irregular spicules of osteoid. The layer of proliferating osteoblasts blends with a deeper zone of bony trabeculae rimmed by osteoblasts and separated by intertrabecular spaces of moderate cellular density. Incomplete surgical excision resulted in local recurrence, while rostral mandibulectomies resulte...
Broström H, Fahlbrink E, Dubath ML, Lazary S.The distribution of equine leucocyte antigens (ELA) in Swedish Halfbreds affected by sarcoid tumors was determined and compared with that of control horses of the same breed. ELA-haplotype A3W13 appeared more frequently in affected horses, resulting in a chi 2 value of 4.45 (P = 0.034) for A3 and 9.05 (P = 0.0026) for W13, respectively. The relative risk factor (RR) could be estimated to 2.13 and 3.00 for A3 and W13, respectively. The etiology fraction (EF) was calculated to 28% and 37% for A3 and W13, respectively. Thus, in the population of Swedish Halfbreds approximately 40% (at least) of t...
Adams R, Calderwood-Mays MB, Peyton LC.A highly successful surgical technique for removing cutaneous tumors in humans was used in seven horses with cutaneous squamous cell carcinoma (n = 3) or sarcoid (n = 4). In humans, the complete underside of the tumor is evaluated histologically by processing horizontal sections from the tumor base, and orientation between the wound surface and the undersurface of the excised tumor is maintained by mapping both surfaces. The technique ensures that small foci of residual tumor can be located accurately and removed. Based on our experience, three modifications of the human technique are suggeste...
Millington WR, Dybdal NO, Dawson R, Manzini C, Mueller GP.Equine Cushing's disease is caused by an adenomatous hyperplasia of the intermediate pituitary which secretes high levels of beta-endorphin, ACTH, and other peptide derivatives of POMC. In the present study we found that plasma and cerebrospinal fluid immunoreactive beta-endorphin (i beta-endorphin) levels were 60- and 120-fold higher than control values in horses with Cushing's disease. There were no significant differences in intermediate lobe i beta-endorphin concentrations, although anterior lobe i beta-endorphin was significantly reduced in Cushing's horses, presumably because high levels...
Whiteley HE, Sundberg JP.A group of spontaneously occurring animal papillomas which were negative or positive for papillomavirus group-specific antigen were examined with a battery of biotinylated lectins including Con A, WGA, succinylated-WGA, PNA and UEA-I. Canine papillomas, equine papillomas, white-tailed deer fibromas, mule deer fibromas, and bovine fibropapillomas were examined. Each lectin had a specific staining pattern. No obvious differences in staining patterns between normal skin, viral antigen-positive and -negative neoplasms were identified. This may be due to the well-differentiated and organized nature...
Doran R, Allen D, Gordon B.Ovarian granulosa theca cell tumours were removed surgically in 10 mares. Stapling instruments were used to facilitate haemostasis of the ovarian pedicle in five out of 10 cases and as a sole method of haemostasis in the remaining five cases. Postoperative haemorrhage from the ovarian pedicle was suspected in only one case. All cases survived long term follow-up from six months to four years. Results from this series of cases indicate that stapling instruments provide a rapid, easy and efficient means of ligating ovarian pedicles when performing ovariectomy in the mare.
Angelos J, Oppenheim Y, Rebhun W, Mohammed H, Antczak DF.The relationship between breed and the risk of developing sarcoid tumours or uveitis of unknown etiology was evaluated in a retrospective study of 16242 equine cases admitted between 1975 and 1987 to the New York State College of Veterinary Medicine Large Animal Hospital, and 3198 equine tissue samples sent to the New York State Veterinary Diagnostic Laboratory between 1977 and 1987. Of 120 sarcoid cases from the Large Animal Hospital, sarcoids were twice as likely to develop in Quarter Horses (odds ratio, OR = 1.8, P less than 0.05) relative to Thoroughbreds and less than half as likely to de...
Romagnoli SE, Momont HW, Hilbert BJ, Metz A.Two yearling, paternal half-sibling Appaloosa fillies were ovariohysterectomized for treatment of multiple uterocervical leiomyomas. The tumors recurred in both fillies, originating from cervical tissue that could not be removed at surgery. Previously reported cases of uterine leiomyoma in the mare have been of solitary tumors in older mares that were treated successfully by surgical removal.
Moll HD, Slone DE, Juzwiak JS, Garrett PD.A diagonal paramedian approach to the abdomen was used for unilateral ovariectomy in 15 mares. In each case, surgery was performed for removal of a granulosa cell tumor. All horses recovered from surgery with minimal complications. Surgical exposure of the affected ovary was adequate to allow exteriorization and ligation. Other advantages of this approach were ease of closure and lack of postsurgical complications.
Clem MF, DeBowes RM, Leipold HW.A mass originating from the dorsal rectal wall of a 4-year-old mare was diagnosed as a leiomyosarcoma. General anesthesia and meticulous surgical dissection were required to effect removal. In spite of incomplete excision, as indicated by histologic sections, the mass has not recurred in the 18 months since removal.
Munson L.A 17-year-old Quarter Horse mare developed rapidly progressive, bilateral, firm enlargements of both mammary glands, ventral abdominal edema, dyspnea, and neurologic signs. The horse was euthanatized, and a carcinoma of the mammary gland was diagnosed at necropsy. Microscopically, normal glandular parenchyma was replaced by neoplastic nodules, and the tumor had metastasized to most visceral organs and throughout the musculoskeletal and central nervous systems. The tumor had a solid pattern, with microglandular differentiation, and numerous syncytial sheets.
Paradis MR.Neoplasia of the central nervous system (CNS) can be divided into two main categories: nonpituitary CNS neoplasia and pituitary adenomas. Nonpituitary CNS neoplasias are generally compressive in nature, although some are also invasive. The majority of reported CNS tumors are secondary with only a few originating from nervous tissue. Pituitary adenomas predominantly occur in the pars intermedia of the older horse. Clinical signs, diagnostic testing, and possible treatments are discussed.
Saroglu M, Aktas M, Olgun D, Arun SS.A tumor-like tissue mass of lateral-limbal site in the right eye of a 12-year-old Cob Pony mare was presented for surgical removal. The mass, covering the lateral limbus, bulbar conjunctiva and part of the cornea, was surgically removed, and the corneal defect repaired with a pedicle bulbar conjunctival graft. The mass was inflammatory in nature containing mononuclear cells. No recurrence or complication occurred at 6- and 12-month follow-up examination.
Johnstone AC.Congenital vascular tumours in the skin of the legs of two horses showed histological features at biopsy which were consistent with capillary haemangioma but, at necropsy, one tumour had invaded the superficial digital flexor tendon and was therefore classified as a haemangiosarcoma.
Lubczyk B, Nothelfer HB.A case of generalized equine leucosis is presented. The most important clinical signs were cachexia, loss of condition, fever, tachycardia, subcutaneous tumors and severe lameness accompanied by edema of the right thoracic limb. Hematology showed anemia and neutrophilia; clinical biochemistry indicated hypalbuminemia, hyperphosphatemia and hyperfibrinogenemia. Necropsy revealed multiple tumors throughout the body which mainly originated from lymph nodes. Histopathologically the tumors consisted of two cell-types: a. uniform lymphocytoid cells with a highly infiltrative growth pattern; b. heter...
Ochi A, Nishioka T, Kurimoto S, Kishi D, Ueno T, Nukada T.A 2-year-old male Thoroughbred horse presented with a mass in the maxilla. The focally ulcerated mass, approximately 8 cm in diameter, covered the upper left intermediate and corner incisor teeth (nos. 602 and 603 according to the modified Triadan system) and radiographic examination revealed displacement and lysis of the incisors. Histologically, the tumour was composed of a dense proliferation of spindle-shaped cells and neoplastic odontogenic epithelial cells arranged in island, follicular, plexiform or sheetlike patterns. The spindle-shaped cells were immunopositive for cytokeratins AE1/A...
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...
De Paolis L, Armando F, Montemurro V, Petrizzi L, Straticò P, Mecocci S, Guarnieri C, Pezzolato M, Fruscione F, Passeri B, Marruchella G, Razzuoli E.Vulvar squamous cell carcinoma (VSCC) has been recently associated with Equus caballus papillomavirus type 2 (EcPV2) infection. Still, few reports concerning this disease are present in the literature. Objective: To describe a case of naturally occurring EcPV2-induced VSCC, by investigating tumour ability in undergoing the epithelial-to-mesenchymal transition (EMT). Methods: Case report. Methods: A 13-year-old Haflinger mare was referred for a rapidly growing vulvar mass. After surgical excision, the mass was submitted to histopathology and molecular analysis. Histopathological diagnosis was c...
McCowan C, Stanley RG.Abstract A heavily pigmented tumor was removed from the lateral, perilimbal, bulbar conjunctiva of a bay Thoroughbred horse. Excision was incomplete and the base of the tumor was lasered on the assumption that the tumor was a melanoma. No other ophthalmic lesions were seen. Histology showed the mass to be a pigmented squamous cell carcinoma (SCC). The prognosis and recommended treatment protocols are different for SCC and melanoma. This is, to the best of our knowledge, the first report of an ocular, pigmented SCC in the veterinary literature.
Whiteley HE, Sundberg JP.A group of spontaneously occurring animal papillomas which were negative or positive for papillomavirus group-specific antigen were examined with a battery of biotinylated lectins including Con A, WGA, succinylated-WGA, PNA and UEA-I. Canine papillomas, equine papillomas, white-tailed deer fibromas, mule deer fibromas, and bovine fibropapillomas were examined. Each lectin had a specific staining pattern. No obvious differences in staining patterns between normal skin, viral antigen-positive and -negative neoplasms were identified. This may be due to the well-differentiated and organized nature...
Loynachan AT, Bryant UK, Williams NM.A 35-year-old horse was submitted to the necropsy service at the University of Kentucky Livestock Disease Diagnostic Center. At necropsy, multiple 1-4-cm-diameter cystic structures were incidentally identified unilaterally in the right renal medulla and the cortex. On histologic examination, the cystic structures compressed the normal renal architecture, were lined by tall columnar epithelium that formed occasional papillary projections, and contained large amounts of mucicarmine and periodic acid-Schiff-positive mucinous material. The masses were diagnosed as renal mucus-gland cystadenomas. T...
Pérez-Écija A, Estepa JC, Barranco I, Rodríguez-Gómez IM, Mendoza FJ, Gómez-Laguna J.Verrucous hemangiomas are a rare specific variant of equine skin tumors not well described in the literature. An 8-year-old gelding presented a unilateral lesion on the pastern. Macroscopically, the mass showed a warty and verrucous surface with focal ulcerations. The histology showed a dermal proliferation of endothelial-layered capillaries and venules separated by a delicate stroma of scant fibroblasts and collagen deposition, with pseudoepitheliomatous hyperplasia (exuberant reactive irregular epithelial hyperplasia with tongue-like projections extending into the dermis, mimicking downgrowt...
Nickels FA, Brown CM, Breeze RG.A unilateral pulmonary granular cell tumor occurred in a Thoroughbred mare with longstanding respiratory disease wrongly attributed to chronic obstructive pulmonary disease. The clinical features, radiology and endoscopic appearance permitted an accurate diagnosis, which was supported by subsequent necropsy and histologic examination. Obstructive pulmonary disease was ruled out after measurement of arterial blood gases and maximum intrathoracic pressure changes, and after microscopic examination of the lung.
Stutsel M, Gimeno M, Young A, Bell JW, Horadagoda N.A 2-year-old Standardbred gelding was referred for a mass on the palmaromedial right front pastern which was accompanied by progressively worsening lameness. The mass was firm to palpation and covered by normal skin. Ultrasonographically, a smooth encapsulated mass was present, medial to the flexor tendons and palmar to the neurovascular bundle. Because of a poor prognosis for future athletic performance without surgical or chemotherapeutic intervention and economic constraints preventing further diagnostics and treatment, the horse was euthanised. Post-mortem magnetic resonance imaging, histo...
Nasir L, Reid SW.An evolutionary conserved 1.3 kb fragment corresponding to the horse p53 tumour suppressor gene was PCR amplified, cloned and the nucleotide sequence determined. The p53 fragment encoded exons 5 to 9 and the intervening introns. The nucleotide sequence and the predicted aminoacid sequence showed a high level of homology with human and donkey p53 sequences.
Broome TA, Allen D, Baxter GM, Pugh DG, Mahaffey E.A 2-year-old Arabian filly was referred for evaluation of a serosanguineous vaginal discharge. Palpation per rectum revealed a large, fluid-filled uterus and a uterine mass. The filly developed septic metritis and secondary laminitis as a result of torsion and necrosis of a pedunculated uterine mass. Ovariohysterectomy was performed. The entire cervix was removed with the uterus. Gross examination of the excised uterus revealed 3 intraluminal masses. Histologic evaluation identified the tumors as fibroleiomyoma. The filly recovered completely, and there was no recurrence of the tumor.
Fidel JL.Although the diagnosis of cancer is relatively uncommon in horses, tumors do occur in this species. Surgery, radiation, and chemotherapy are traditional cancer treatments in all species. In equine patients, surgery has often been the only treatment offered; however, not all tumors can be controlled with surgery alone. In small animal oncology, newer and better therapies are in demand and available. Radiation therapy is often used to control or palliate tumors locally, especially to satisfy clients who demand sophisticated treatments. The large size of equine patients can make radiation therapy...
Gebhart W, Niebauer GW.The morphological substrates of pigmented and depigmented skin as well as the structural characteristics of spontaneously developing melanomas were revealed by clinical, light- and electron microscopic methods in gray horses (Lipizzaner breed) from the Vienna Spanish Riding School. On clinical investigations in a group of 31 older horses (more than 10 years old) 20 exhibited melanomas, whereas 23 younger animals (less than 10 years of age) had no evidence for visuable melanotic tumors. Concomitantly with the progressive graying of the hair a depigmentation of the skin was frequently observed. ...
Jaeschke G, Rudolph R.The literature contains about 500 cases of equine leucosis, though the reports are deposited in a great number of journals and vary considerably concerning particular topics. During the last years there has been a remarkable increase of publications about this syndrome in the equine. The clinical leucosis key recommended by us has been confirmed in principle considering the latest literature. In about 70 individual symptoms which can be clinically observed in equine with leucosis 11 can be considered as main symptoms because of their frequency; they are again classified in primary (lymph node ...
A 1.8-year-old maiden Thoroughbred filly, without previous history of mating or reproductive management, was referred for clinical inspection due to the presence of sanguineous vaginal discharge and severe abdominal pain. Transrectal palpation indicated uterine asymmetry, and transrectal ultrasonography revealed a mass near the cervix measuring 8.3 cm in diameter, with heterogeneous echogenicity, a trabeculated center, and a well-defined hyperechoic border. Smaller masses surrounded the larger uterine mass. During the examination, the mare expelled a uterine mass through the vulva. Histologica...
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 ...
Kofler J, Kübber-Heiss A, Schilcher F.Clinical, ultrasonographic and pathological findings of a cutaneous, multilocular T-cell lymphosarcoma (malignant lymphoma) in a 13-year-old, brown Austrian warmblood mare are reported. The horse was under clinical observation, and the tumours were sonographically monitored over an 8 month period, revealing worsening of body condition, weight loss, lameness of the left hindlimb and a slight increase in the tumours size. Most of the tumours were covered by normal skin, one showed ulceration. Ultrasonography of the tumours allowed accurate anatomical localization in relation to the adjoining tis...
Hinrichs K, Watson ED, Kenney RM.A functional corpus luteum was found in the ovary contralateral to the ovary with a granulosa cell tumor in a 24-year-old Standardbred mare. The mare was ovariectomized because she was to be used as a jump mare for collection of semen from stallions. The blood concentration of progesterone was 2.2 ng/ml, and the luteal tissue progesterone concentration was 6.3 micrograms/mg. Atrophy of the contralateral ovary is one of the major signs used in diagnosis of granulosa cell tumor; however, our findings indicate that the ovary contralateral to a granulosa cell tumor is not invariably nonfunctional....
Fadok VA.Papules and nodules are common lesions on horses and have a variety of underlying causes. This article addresses inflammatory and congenital nodules primarily, including urticaria, erythema multiforme, those nodules caused by infectious agents, epidermoid and dermoid cysts, and the uniquely equine skin tumor, the sarcoid. The eosinophilic nodules and other tumors are covered elsewhere in this issue. Diagnostic and therapeutic approaches to each of the diseases are emphasized.
Rowe EL, Sullins KE.To determine whether excision was an acceptable treatment for dermal melanomatosis in horses. Methods: Retrospective study. Methods: 11 horses with dermal melanomatosis involving the perineal, perianal, or perirectal region or ventral surface of the tail in which treatment consisted of tumor excision. Methods: Medical records were reviewed. Follow-up information was obtained from owners through telephone interviews. Results: 9 of the 11 horses were alive at the time of follow-up interviews. None of the horses had regrowth at the surgery site where the primary tumor was removed. There were no c...
Potter K, Anez D.A 17-year-old Quarter Horse mare was examined to determine the cause of a vulvar mass. Differential diagnoses for the swollen, ulcerated tissue included hypersensitivity reaction to insect stings or bites and cutaneous neoplasia. During the next 4 months, the mass enlarged involving the skin of the perineum and ventral aspect of the abdomen with secondary dependent edema of both hind limbs. Histologic examination of biopsy and necropsy specimens revealed changes consistent with a diagnosis of mycosis fungoides (cutaneous T-cell lymphoma). Diagnostic features included invasion of neoplastic lym...
Reid N.A round mass 4 cm in diameter was present on the proximal rostro-lateral border of the right pinna of a 10-year-old, gelded, Paint horse. A preliminary histopathological diagnosis of a potential squamous cell carcinoma and peripheral nerve sheath tumor was made, and the lesion was resected at the base of the lateral edge of the ear. Une masse ronde de 4 cm de diamètre était présente sur le bord rostrolatéral proximal du pavillon de l’oreille droite d’un Paint horse castré âgé de 10 ans. Un diagnostic histopathologique préliminaire d’un carcinome squameux et d’une tumeur de la ...
Steinmetz A, Gittel C, Böttcher D, Lapko L, Offhaus J.A melanoma of the upper eyelid was resected in a gray warmblood gelding. A full functional eyelid could be obtained by completion a sliding skin graft with a free labial mucocutaneous graft transplantation to restore the mucocutaneous junction and to decrease the risk of postoperative trichiasis.
De Lange V, Chiers K, Lefère L, Cools M, Ververs C, Govaere J.Two unilateral cryptorchid stallions were referred to the clinic because of chronic debilitating condition with emaciation. Rectal examination, and ultrasound and gross examination revealed in both animals an abdominal mass, caudally of the kidney, and multiple nodules spread over the abdomen. Histologic analysis revealed an intra-abdominal malignant seminoma with intraperitoneal and renal metastasis. Interestingly, a seminoma was also present in the descended testis of the draught horse.
Bockenstedt MM, Fales-Williams A, Haynes JS.The placenta from an embryo transfer-recipient mare and live foal was examined. The placenta was effaced by multifocal masses, which ranged from less than 1 cm to 14 cm in diameter. The foal represented at 52 days for lethargy, ataxia, and urine dribbling; due to a poor prognosis, the foal was euthanized. At necropsy, the liver was effaced by multifocal, pale, irregular nodules. The lumbar vertebrae and other skeletal sites had multifocal lytic lesions. The placenta had 4 populations of neoplastic cells, including a spindle cell population, tall columnar and transitional epithelial cell popula...
Stick JA.In three horses with abdominally retained testicles, teratomas with cyst formation were found. Bone development in the head of the epididymis, near the vascular supply of the tumor, was a consistent finding. Aspiration of the cystic portion of the tumor was necessary for surgical removal in two cases. Although germinal carcinoma cells have been suggested as the cause of teratomas, evidence of malignancy was not seen in any of the three tumors.
