Clinical and Immunohistochemical Characterization of Thymic Lymphosarcoma in a Heifer

Abstract

A 2-year-old Holstein heifer with a swollen brisket, jugular vein distention, muffled heart sounds, tachycardia, and free gas bloat was examined. Thymic lymphosarcoma was suspected based on a negative agar gel immunodiffusion test for bovine leukemia virus, presence of atypical lymphocytes in pleural fluid, and detection of a mass in the thoracic inlet. Right-sided cardiac catheterization was performed, and markedly increased jugular venous pressures (41 m m Hg) hymic lymphosarcoma, juvenile multicentric lympho-T sarcoma, and cutaneous lymphosarcoma are 3 sporadic forms of bovine lymphosarcoma that are not associated with bovine leukemia virus (BLV) infection.' Thymic lymphosarcoma produces clinical signs related to an anterior mediastinal mass, such as cervical and submandibular edema, bilateral jugular vein distention, and varying degrees of ruminal tympany, as well as dyspnea, anorexia, and weight loss.',' The clinical signs of thymic lymphosarcoma can therefore be difficult to differentiate from right-sided heart failure (RSHF). In this report, we describe the clinical and pathological findings in a heifer with thymic lymphosarcoma. Thoracocentesis, ultrasonography, electrocardiography, cardiac catheterization, and immunohistochemical staining pennitted detailed characterization and classification of this case. Case DescriptionA 2-year-old Holstein heifer was examined because of a 6-day history of a swollen brisket, anorexia, and free gas bloat. The heifer had been previously treated for bloat by oral-ruminal passage of a stomach tube and intraruminal administration of liquid fat and magnesium hydroxide. A magnet (PO), procaine penicillin G (IM), and ceftiofur sodium (IM) (doses unknown) had also been administered for treatment of suspected traumatic reticulopericarditis.The heifer appeared depressed and had bilateral abdominal distention. Rectal temperature and respiratory rate were within normal limits, while the pulse rate was increased (1 05 beatshinute). The heart and lung sounds were difficult to auscultate over the entire left side of the thorax, but could be heard normally over the right side of the thorax. Pitting edema extended from the thoracic inlet to the ramus of the mandible, and both jugular veins were greatly distended. Edema and venous distention were not evident caudal to the brisket. Palpation of the brisket revealed a 10-cm diameter, firm mass that extended deep into the thoracic inlet. The mass was fixed in place and surrounded by a markedly edematous subcutis, and the cervical skin was cold to the touch. Palpation per rectum revealed ruminal gas distention and a gravid uterus of approximately 7 months gestation. The feces were dark green and contained frank blood and mucus. A 3-cm diameter stomach tube was easily passed into the mmen and a large volume of gas released with subsequent decrease in abdominal distention.The heifer had a normal blood leukocyte count (9,000 cells/pL; normal, 4,000 to 12,000 cells/pL), normal lymphocyte count (3,150 cells/pL; normal, 2,500 to 7,500 cells/pL),...

Thymic Lymphosarcoma with Brain Involvement in a Holstein Heifer

“…Macroscopic neoplastic lesions are distributed across lymph nodes, bone marrow, liver, spleen, kidneys, lungs, and thymus [13]. Brain and spinal cord are usually not directly affected in this form of SBL [1,2,4,7,10,13,16]. Here, we present a rare clinical case of thymic lymphosarcoma accompanied by brain involvement in a Holstein heifer.…”

“…Involvement of the central nervous system (CNS) is a common clinical observation in EBL [5]. However, the brain and spinal cord are usually not directly affected by the thymic form of lymphosarcoma [1,2,4,7,10,13,16]. One exception was a clinical case of thymic lymphosarcoma with metastases causing spinal cord compression and pelvic limb paresis in a heifer [11].…”

Lymphosarcoma in a Boar

“…In the present case, the neoplastic lymphoid cells were positive for CD3, but not for CD79 and BLA, supporting the diagnosis of a T‐cell lymphosarcoma. Polyclonal CD3 antibody also cross‐reacts with canine (Ferrer et al., 1992; Day, 1995), bovine (Alexander et al., 1996) and equine (Kelley and Mahaffay, 1998) T cells. Kadota et al.…”

Myeloblastic Leukemia with Massive Neoplastic Infiltration of the Skin and Mediastinum in a Cow.

“…The present tumor, which had massive or nodular neoplastic lesions in the dermis and mediastinum, could not be differentiated distinctly from these lymphomas in HE preparations. The control case of skin lymphoma as well as thymic lymphoma cases [1,26] exhibited CD3 positivity, and the presence of MHC II was demonstrated in enzootic [23] and sporadic B-cell [18] lymphomas. The present tumor had neither and was suggested to have originated from nonlymphoid tissue.…”

“…The antibodies to CD3 and CD79a used in the present study had broad species cross-reactivity, and were effective in paraffin sections in determing the phenotype of canine, feline and porcine lymphomas [4,19]. In addition, the anti-CD3 antibody was utilized for the identification of thymic T-cell lymphomas in cattle [1,26] and of a simian T-cell lymphoma [16]. These antibodies are also available for the analysis of the inflammatory infiltrate in neoplastic or infectious diseases [13,14].…”