Topic:Lymphoma
Lymphoma in horses is a type of cancer that originates in the lymphoid tissues, which are part of the immune system. It involves the uncontrolled proliferation of lymphocytes, a type of white blood cell. Lymphoma can affect various organs and systems in horses, including the lymph nodes, spleen, liver, gastrointestinal tract, and skin. Clinical signs may vary depending on the location and extent of the disease, and may include weight loss, lethargy, swelling of lymph nodes, and abnormal blood work. Diagnosis often involves a combination of clinical examination, imaging, and biopsy. This page compiles peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment options, and prognosis of lymphoma in equine patients.
Clinical and morphological features of corneal lymphoma in 26 horses (27 eyes). Little information describing the biologic behaviour and therapies for corneal lymphoma exist. Objective: To characterise histologically confirmed equine corneal lymphoma considering breed, age or sex predisposition, histologic and immunologic features, therapies and outcomes. Methods: Retrospective case series. Methods: A multicentre retrospective medical record review was used to identify horses that presented with corneal disease confirmed morphologically as corneal lymphoma from 2012 to 2022. Results: Mean age at diagnosis was 10.5 years. Males represented 18/26 cases. Warmblood (14) and...
Lymphoma & Myeloproliferative Disease. Lymphoma and myeloproliferative diseases in horses are relatively uncommon. The clinical signs, prognosis, and treatment options depend upon the anatomic location and subtype. Significant gaps in knowledge remain regarding prevalence, pathogenesis of different subtypes, antemortem diagnostic tests, response to treatment, and standardized treatment protocols. However, treatment options are available, accessible on the farm, and could improve quality of life and prolong survival.
Oral T-cell-rich large B-cell lymphoma in a horse. Lymphoma is the most common tumor of hematopoietic origin in horses. The course of the disease and clinical signs vary greatly, depending on tumor location and extent. The aim of this report is to describe the occurrence of T-cell-rich oral large B-cell lymphoma with marked local infiltration in a 25-year-old Crioula mare. The mare showed an increase in volume on the right side of its face, dyspnea, anorexia, and progressive weight loss. The clinical assessment showed that the lesion was located in the rostral and caudal sinuses and was markedly invasive to adjacent structures. The autopsy rev...
Chemotherapeutics in Equine Practice. Chemotherapy is the treatment of cancerous cells through the use of cytotoxic drugs. Whilst the use of systemic (intravenous) chemotherapy in equine practice is generally limited to the management of lymphoma, cytotoxic drugs are commonly used in the treatment of accessible skin tumors, either by topical application in the form of ointments or injected intralesionally. These drugs should be employed with caution due to the risk of serious adverse effects. In addition, extreme caution should be followed when preparing, handling, administering, and disposing them, due to their carcinogenic, muta...
A multicentric intermediate-size B-cell lymphoma with epitheliotropism in a Freiberger mare. This report describes a multicentric intermediate-size B-cell lymphoma with epitheliotropism in a Freiberger mare affecting multiple mucous membranes, skin and internal organs. The clonal neoplastic B-cell population was accompanied by numerous reactive polyclonal small T cells. Differential diagnoses for these unusual findings are discussed. 本报告描述了一种多中心性中等大小B细胞淋巴瘤, 其在弗雷伯格母马中具有驱上皮性, 影响多处粘膜、皮肤和内脏。克隆性肿瘤B细胞群伴有大量反应性多克隆小T细胞。就这些异常发现对鉴别诊...
A case of equine multicentric lymphoma: Clinical, microscopical, and molecular findings. Although relatively uncommon, lymphoma is the most prevalent haematopoietic neoplasia in horses, and multicentric lymphoma remains the most common presentation of the disease. The pathogenesis of equine lymphoma is still poorly understood and the diagnosis is usually confirmed at an advanced stage of the disease, compromising the prognosis. This study investigated the clinical, pathological, and molecular features of a case of equine multicentric lymphoma. Unassigned: An apparently healthy 5-year-old crossbreed mare hospitalized at the Centre of Animal Reproduction of Vairão, Portugal, sudden...
Multicentric lymphoma in a donkey with intestinal and bone marrow involvement. Lymphoma is a common neoplasm in horses but is reported much less commonly in donkeys. In this case report, we describe the macroscopic, microscopic and immunohistochemical features of a multicentric lymphoma with intestinal and bone marrow involvement. Methods: A geriatric female donkey with history of chronic lameness was found dead. Post-mortem examination revealed advanced emaciation, periodontal disease, left front foot laminitis and multiple, soft, white to yellow tan intestinal transmural masses, up to 12 cm in diameter. Cytology suggested a round cell intestinal neoplasm. The femur of...
Equine common variable immunodeficiency: lessons from 100 clinical cases. The clinical manifestation of recurrent fevers and infections alerts the clinician to the possibility of an underlying immunodeficiency. Common variable immunodeficiency (CVID) in the horse is a rare late-onset, non-familial immunologic disorder of B cell depletion and/or dysfunction with resultant inadequate antibody production. The most common clinical presentations in horses with CVID are recurrent upper and/or lower respiratory infections, meningitis and/or ataxia, cholangiohepatitis, infectious colitis, infectious dermatitis, and severe gastrointestinal parasitism. Immune-mediated and lym...
Head and neck squamous cell carcinoma with heterotopic ossification, lymphovascular invasion, and nodal and pulmonary metastases in a 23-year-old Morgan gelding. Primary squamous cell carcinoma of the head and neck occurs in the skin or squamous epithelial lining tissues of the oral cavity, pharynx, larynx, and sinonasal tract. Although it is a common tumor in horses, distant metastatic spread to the lung is rare. This report describes a case of metastatic pulmonary squamous cell carcinoma in a 23-year-old Morgan gelding. The clinical signs displayed by this gelding in some ways mimicked the typical presentation of equine multinodular pulmonary fibrosis or thoracic lymphoma. The postmortem diagnosis in this case was head and neck squamous cell carcinom...
An Unusual Cause of Femoral Nerve Paresis in a Horse: Disseminated B Cell Lymphoma With Plasmacytoid Differentiation and Direct Neuronal Invasion. A 21-year-old Quarter Horse mare presented with a chronic, progressively worsening left pelvic limb lameness of 3 weeks duration. The initial examination identified a consistent lameness at a walk. Neurological examination showed sensory and gait abnormalities consistent with left femoral nerve dysfunction. The horse minimally advanced the leg cranially and had a shortened stride length at the walk. During the stance phase, the heels of the left hind foot did not contact the ground and the horse quickly took weight off of the limb. Diagnostic imaging (ultrasound and nuclear scintigraphy) exami...
T-cell-rich, large B-cell lymphoma in the brain of a horse. T-cell-rich, large B-cell lymphoma (TCRLBCL) is the most commonly diagnosed type of lymphoma in horses. Here we describe the clinical signs, neuropathology, immunohistochemistry (IHC), and PCR for antigen receptor rearrangement (PARR) analysis results of a TCRLBCL in the brain of an 8-y-old male Quarter Horse that was euthanized after acute anorexia, tremors, head pressing, falling, blindness, incoordination, and seizures. Autopsy revealed a firm, smooth, pale-yellow mass that expanded both lateral ventricles and the adjacent subcortical white matter. Histologically, the mass consisted of a de...
Colonic T-cell-rich, large B-cell lymphoma associated with equid herpesvirus 5 infection and secondary trans-colonic fistula in a horse. A 17-y-old Rocky Mountain gelding was presented to the Virginia-Maryland Veterinary Teaching Hospital because of a 4-wk history of anorexia, weight loss, lethargy, and fever of unknown origin. Abdominal ultrasound revealed lymphadenomegaly of the abdominal and colonic lymph nodes, thickening of the wall of the large colon, and a mass associated with the large colon. The horse was euthanized given a poor prognosis. On autopsy, an ~20-cm diameter mass was found within the mesocolon between the right ventral and right dorsal colon. The mass had invaded through the colonic walls and formed a fistu...
Association of globulin concentrations with prognosis in horses with lymphoma. Lymphoma is the most common hemopoietic neoplasia in horses. Common clinicopathologic abnormalities in equine lymphoma include hyperglobulinemia, hypoalbuminemia, hyperfibrinogenemia, anemia, thrombocytopenia and lymphocytosis. Hypoglobulinemia has been reported in other species with lymphoma, however it has not been well-described in horses. The objectives of this study were to examine the prevalence of hypoglobulinemia in equine lymphoma, and to identify prognosis and clinicopathological abnormalities associated with serum globulin concentrations. Unassigned: Ninety-six horses with lymphoma ...
Markers for internal neoplasia in the horse. The diagnosis of internal neoplasia in horses is challenging. Increased production of hormones physiologic for adult animals (e.g., adrenocorticotropin, norepinephrine, and erythropoietin) or typical for the foetal phase (alpha-fetoprotein, anti-Müllerian hormone, and parathyroid-hormone-related protein) might aid in tumour diagnostics. Thymidine kinase-1 and alkaline phosphatase are examples of intracellular enzymes, whose activity in the blood may increase in some neoplasia cases. Furthermore, inappropriate production of abnormal monoclonal or autologous antibodies can accompany lymphoma an...
Lymphomatosis as a Cause of Abdominal Pain and Distension in Two Adult Horses. Two equine patients presented separately with severe abdominal distention, colic, lethargy, and decreased appetite. An ante-mortem diagnosis of lymphoma was reached in each case based on peritoneal fluid cytology. Due to a poor prognosis, the horses were humanely euthanized. Post-mortem examination with histology and immunohistochemistry confirmed both cases as lymphoma: alimentary B-cell lymphoma of the distal jejunum and cecum in one case, and T-cell lymphoma of the cecum in the second case. Both cases exhibited extensive metastasis with peritoneal and pleural serosae covered in small nodule...
Cutaneous epitheliotropic T-cell lymphoma in a donkey – a case report. Cutaneous epitheliotropic T-cell lymphoma is a malignant tumour of the skin already reported in humans, dogs, cats, horses, and other species, but not previously in donkeys. The standard diagnosis is based on clinical, morphological and immunophenotypic data. Differentiation of malignant versus benign proliferation of lymphocytes is crucial; in ambiguous cases T-cell receptor gamma (TRG) molecular clonality should be tested. In the present paper, we report a case of mycosis fungoides diagnosed in a donkey whose diagnosis was based on clinical, histological and immunohistochemical aspects and a...
Molecular characterization of equine thymidine kinase 1 and preliminary evaluation of its suitability as a serum biomarker for equine lymphoma. Thymidine kinase 1 (TK1) plays a key role in the synthesis of deoxythymidine triphosphate (dTTP) and is thus important for DNA replication and cell proliferation. The expression of TK1 is highest during S-phase, and it is rapidly degraded after mitosis. In cancer cells, TK1 is upregulated, resulting in leakage of excess TK1 into the blood. Consequently, serum TK1 has been used as a diagnostic and prognostic cancer biomarker, mainly in human medicine. The aims of this work were to characterize equine TK1 and to evaluate its suitability as a serum biomarker for equine lymphoma. Results: Equine T...
Clinical performance of a commercially available thymidine kinase 1 assay for diagnosis of lymphoma in 42 hospitalized horses (2017-2020). Antemortem definitive diagnosis of lymphoma in horses is often difficult. Thymidine kinase 1 (TK1) assay is a potentially useful biomarker for lymphoma in horses. Objective: To report the clinical performance of a commercially available TK1 assay for diagnosis of lymphoma in horses. We hypothesized that there would be no association between serum TK1 activity and a diagnosis of lymphoma in horses. Methods: Forty-two hospitalized horses, 14 with a definitive diagnosis of lymphoma, 4 with other neoplasia, and 24 with inflammatory disease. Methods: Retrospective medical record review, groups were...
Nonclassified Lymphoma as a Cause of Radial Nerve Paralysis in a Horse. A 4-year-old American Quarter Horse gelding was evaluated for acute non-weight-bearing lameness of the right thoracic limb with swelling in the right shoulder region. Physical examination revealed radial nerve paralysis of unknown etiology. The primary differential diagnosis was musculoskeletal trauma. Ultrasonography of the right shoulder region identified a heterogeneous mass that extended from the point of the shoulder to the thoracic inlet. Cytologic analysis of fluid collected by fine needle aspirate of the mass was consistent with large cell lymphoma. Based on the cytological findings, l...
Facial nerve paralysis in 64 equids: Clinical variables, diagnosis, and outcome. Facial nerve paralysis (FNP) in equids is not well described in the veterinary literature. Objective: To investigate the causes of FNP and associations among clinical variables, diagnosis, and outcome. Methods: Sixty-four equids presenting with FNP between July 2000 and April 2019. Cases of postanesthetic FNP were excluded. Methods: Medical records were retrospectively reviewed. Variables were evaluated for associations with outcomes (diagnosis and case outcome) using logistic regression. Results: The most common cause of FNP was trauma (n = 20). Additional diagnoses included central nervous s...
Equine Intestinal Lymphoma: Clinical-Pathological Features, Immunophenotype, and Survival. Lymphoma is the most common intestinal neoplasm in horses, but its clinical-pathological features are poorly characterized. Primary intestinal lymphoma was diagnosed in 20 horses on biopsy samples and further confirmed by postmortem examination in 16 cases. Lymphoma was found in the small intestine in 12 of 20 (60%), in the colon in 5 of 20 (25%), and in both small and large intestines in 3 of 20 (15%) cases. Gross findings included thickening of the intestinal wall (45%), mural nodules or masses (30%), and both thickening and nodules (10%). Cases were classified according to the human World H...
An atypical presentation of multi-systemic B-cell lymphoma in a horse. This report describes an unusual presentation of multicentric B-cell lymphoma with central and peripheral nerve involvement in a horse that was presented with acute onset, severe, multiple limb lameness, and muscle atrophy. This case highlights the importance of including neoplasia in the differential list in horses presenting for severe limb lameness associated with muscle atrophy, muscle fasciculations, and weakness. Présentation atypique d’un lymphome à cellules B multisystémique chez un cheval. Ce rapport décrit la présentation inhabituelle d’un lymphome à cellules B multicentriq...
Clinical and immunophenotypic findings in 4 forms of equine lymphoma. The clinical, histological, and immunophenotypic findings are presented for 4 horses affected by different types of lymphoma. Diagnoses of a monomorphic epitheliotropic intestinal T-cell lymphoma, a diffuse splenic large B-cell lymphoma, a peripheral T-cell lymphoma, and a T-cell rich large B-cell lymphoma of the third eyelid were made. Constatations cliniques et immunophénotypiques pour quatre formes de lymphomes équins. Les constatations cliniques, histologiques et immunophénotypiques sont présentées pour quatre chevaux affectés par différents types de lymphome. Des diagnostics d’un...
Retrospective evaluation of clinical outcome after chemotherapy for lymphoma in 15 equids (1991-2017). Prognosis associated with lymphoma in horses is poorly characterized, and treatment is often palliative. Long-term outcome after chemotherapy for horses with lymphoma is not well documented. Objective: To report long-term outcome of horses with lymphoma treated with chemotherapy. Methods: Fifteen equids. Methods: Retrospective case series. Medical record search and call for cases on the ACVIM listserv for horses treated with chemotherapy for lymphoma. Results: Fifteen cases with adequate data were identified. Complete remission was achieved in 5 horses (33.3%), partial response was achieved in...
Clinical features and outcome in horses with severe large intestinal thickening diagnosed with transabdominal ultrasonography: 25 cases (2003-2010). OBJECTIVE To describe clinical features and outcome of horses with severe large intestinal thickening diagnosed with transabdominal ultrasonography. Methods: Retrospective case series. ANIMALS 25 horses. PROCEDURES Medical records of horses that underwent transabdominal ultrasonography between 2003 and 2010 were reviewed. Horses were included if the wall of the large intestine was ≥ 9 mm thick in any of 6 abdominal zones. RESULTS Median age was 13 years (range, 3 to 28 years). Horses were initially examined because of colic, diarrhea, inappetence, weight loss, lethargy, fever, or hematuria. ...
[A case of leptomeningeal melanomatosis with acute paraplegia and multiple cranial nerve palsies]. A 62-year-old man with acute paraplegia was transferred to our hospital. He had flaccid paraplegia and multiple cranial nerve palsies, such as mydriasis of the left pupil, abduction palsy of the left eye, hoarseness and dysphagia, but no meningeal irritation signs. MRI of the spinal canal showed swellings of the conus medullaris and the cauda equine, and also contrast enhancement of the spinal meninges. The cerebrospinal fluid (CSF) showed pleocytosis and protein increment. The lymph node was swollen in his right axilla. The biopsy specimen from the right axillary lymph node revealed metastasi...
Blindness associated with nasal/paranasal lymphoma in a stallion. A 29-year-old stallion presented with bilateral blindness following the chronic purulent nasal drainage. The mass occupied the right caudal nasal cavity and right paranasal sinuses including maxillary, palatine and sphenoidal sinuses, and the right-side turbinal and paranasal septal bones, and cribriform plate of ethmoid bone were destructively replaced by the mass growth. The right optic nerve was invaded and involved by the mass, and the left optic nerve and optic chiasm were compressed by the mass which was extended and invaded the skull base. Histologically, the optic nerves and optic chia...
Extreme lymphocytosis with myelomonocytic morphology in a horse with diffuse large B-cell lymphoma. An 11-year-old, 443-kg Haflinger mare was presented to the North Carolina State University Veterinary Teaching Hospital with a 2-week history of lethargy and a 3-day duration of anorexia, pyrexia, tachycardia, and ventral edema. Severe pitting edema, peripheral lymphadenopathy, and a caudal abdominal mass were noted on physical examination. An extreme leukocytosis (154.3 × 103 /μL) and microscopic hematologic findings suggestive of myelomonocytic leukemia were observed. Serum protein electrophoresis revealed a monoclonal gammopathy and urine protein electrophoresis revealed a monoclonal ligh...
Neoplasia in 125 donkeys (Equus asinus): literature review and a survey of five veterinary schools in the United States and Canada. A diagnosis of neoplasia was noted in 125 of 357 donkeys (35%) in our review of medical records from 5 veterinary schools in the United States and Canada. Equine sarcoid was the most common tumor in our study, accounting for 72% of all tumors and 82% of cutaneous tumors. Soft-tissue sarcomas were the second most common skin tumors. All other types of neoplasia were rare. Important differences in the occurrence of neoplasia in donkeys compared to horses included the rarity or absence of squamous cell carcinoma in any organ system and gray horse melanoma. Lymphosarcoma, the most common malignant...
Peritoneal fluid immunocytochemistry used for the diagnosis of a possible case of equine gastrointestinal B-cell lymphoma. After physical examination, ultrasonographic evaluation of thorax and abdomen, and peritoneal fluid analysis, gastrointestinal neoplasia with suspected diffuse peritoneal metastasis was diagnosed in a 17-year-old Arabian gelding. The owner elected euthanasia and declined postmortem examination. Immunocytochemistry analysis of the peritoneal fluid resulted in a diagnosis of B-cell lymphoma. Immunocytochimie du liquide péritonéal utilisée pour le diagnostic d’un cas possible de lymphome gastro-intestinal à cellules B. Après un examen physique, une évaluation échographique du thorax et d...