formed (14 gauge, Tru-cut Biopsy Needle, Travenol. Laboratories, Deerfield, Illinois, USA) under sedation with xylazine (Rompun, Bayer Corporation, Shawnee.
Multicentric lymphosarcoma with ovarian involvement in a Nubian goat W.A. DiGrassie, M.A. Wallace, D.P. Sponenberg Abstract Multiple lymph node enlargement and an intra-abdominal mass were diagnosed in a 6-year-old doe. Necropsy revealed lymphosarcoma involving multiple organs, including the ovaries. Lymphosarcoma is rare in goats; ovarian involvement has not previously been reported.
Resume - Lymphosarcome multicentrique impliquant les ovaires chez une chevre nubienne. Une hypertrophie de multiples ganglions lymphatiques ainsi qu'une masse intra-abdominale ont ete diagnostiquees chez une chevre de 6 ans. La necropsie a revele la presence d'un lymphosarcome impliquant plusieurs organes dans les ovaires. Les lymphosarcomes sont rares chez les chevres; l'implication des ovaires n'avait pas ete rapportee auparavant. (Traduit par docteur Andre Blouin) Can Vet J 1997; 38: 383-384
Nubian doe was to the Virginia A6-year-old, *A, Tech Veterinary Teaching presented Hospital with 2-week a
history of depression, anorexia, and weight loss. A complete blood count and biochemical profile performed by the referring veterinarian revealed that the doe was marginally anemic, mildly eosinophilic, hypoglycemic (2.66 mmol/L; reference range 4.83 to 7.05 mmol/L), and hypocalcemic (1.98 mmol/L; reference range 2.43 to 2.78 mmol/L). Previous therapy included oral calcium and glucose-containing electrolyte solutions, ivermectin, and procaine penicillin G. The goat's serum tested negative for caprine arthritis encephalitis (CAE) on agar gel immunodiffusion (AGID). On physical examination, the doe was depressed, weak, and thin (body condition score 1/5). Rectal temperature was 39.1 °C, heart rate 132 beats/min, and respiratory rate 60 breaths/min. The right submandibular and right prescapular lymph nodes were enlarged but not painful. Exophthalmos and scleral injection were present bilaterally. Bruxism was noted. Lung sounds were harsh bilaterally, but no adventitial sounds were noted. A cardiac arrhythmia with variability in the intensity of the heart sounds was noted on auscultation. Ruminal motility was decreased. A large, firm, caudal intra-abdominal mass was palpable. The differential diagnoses for a caudal abdominal mass included lymphosarcoma, caseous lymphadenitis abscess, pyometra, hydronephrosis, and intestinal adenocarcinoma. Differential diagnoses for lymph node enlargement included caseous lymphadenitis, lymphosarcoma, and reactive lymph node secondary to a local primary infection. The findings on physical examination and the history of rapid systemic deterioration were suggestive of lymphosarcoma. Initial diagnostics included complete blood count, fibrinogen level, serum biochemical profile, abdominal ultrasound, and an agar gel immunodiffusion (AGID) test Department of Large Animal Clinical Sciences (DiGrassie, Wallace), Department of Biomedical Sciences and Pathobiology (Sponenberg), Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia 24061-0442 USA. Con Vet J Volume 38, June 1997 Vet
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for bovine leukemia virus (BLV). The complete blood count and fibrinogen levels were within normal limits. On the biochemical profile, hypoglycemia (3.50 mmol/L) and hypocalcemia (1.8 mmol/L) were noted. Gamma glutamyl transferase (187 U/L; reference range 5 to 25 U/L), aspartate aminotransferase (422 U/L; reference range 1 to 37 U/L), and blood urea nitrogen (5.98 mmol/L; reference range 1.0 to 4.65 mmol/L) were increased. Transcutaneous abdominal ultrasound confirmed the presence of 2, caudal abdominal, homogenous masses. They were believed to be of ovarian origin. Numerous blood vessels were observed throughout the masses and free abdominal fluid was present. An ultrasound-guided biopsy of the mass was performed (14 gauge, Tru-cut Biopsy Needle, Travenol Laboratories, Deerfield, Illinois, USA) under sedation with xylazine (Rompun, Bayer Corporation, Shawnee Mission, Kansas, USA), 0.12 mg/kg body weight (BW), IV, and local infiltrative anesthesia. A fine needle aspirate of the right submandibular lymph node was submitted for cytologic evaluation. The doe was administered 5% dextrose in water at a rate of 4 mL/kg BW and given flunixin meglumine (Banamine, Schering-Plough Animal Health, Kenilworth, New Jersey, USA), at a dose of 1 mg/kg BW, IV. However, she died 7 h after admission.
The biopsy samples contained sheets of pleomorphic neoplastic cells. The cells ranged from 8 to 15 pm in diameter, and most were round or irregularly ovoid. Cytoplasm was scant and eosinophilic. Nuclei were generally vesicular, although many were darkly stained. Nuclei contained 0 to 1 nucleoli in most instances, although rare cells contained up to 4 nucleoli. The nucleoli were generally eosinophilic and varied in size up to 4 pm in diameter. Most high power magnification fields contained 2 to 3 cells in mitosis. The histologic diagnosis was lymphoblastic lymphoma, a highly metastatic neoplasm. On necropsy, several regions of the body, including ovaries, cervix, pericardium at the heart base, right ventricle, right submandibular lymph node, and retropharyngeal lymph node, were infiltrated by a tan, soft, fleshy tissue. The ovaries measured 20 x 20 x 15 cm
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Figure 1. Reproductive tract of a female goat with ovarian lymphosarcoma. The ovaries (20 X 20 X 15 cm) in this goat were 10 times the normal size.
(normal 2.2 X 1.2 cm) (1) and were uniformly infiltrated with neoplastic tissue (Figure 1). Rings of similar neoplastic tissue, 2 mm thick, were found surrounding the hilar bronchioles. The liver was pale, yellow, and greasy. The exophthalmos was the result of retrobulbar masses consisting of tan, fleshy tissue, similar to that of the ovaries. The gross diagnosis was disseminated lymphosarcoma. The histologic diagnosis at necropsy of lymphoblastic lymphosarcoma was consistent with the biopsy results. The results of the AGID test were negative. Caprine lymphosarcoma is a rare neoplastic condition. Of 458 goats presented for necropsy at the New York State College of Veterinary Medicine, a prevalence of 2.2% was reported (2). Typical presentation includes depression, anorexia, and weight loss that often progresses to death within 2 wk of the owner seeking veterinary attention (2). Areas infiltrated with lymphosarcoma typically include the liver, lungs, spleen, peripheral lymph nodes, and the mandible and maxilla (2-4). The goat in this case presented with depression, anorexia, and weight loss and died within 2 wk of initial examination. She also presented with atypical findings of large caudal abdominal masses and exophthalmos. Exophthalmos due to retrobulbar masses has been noted in a goat experimentally infected with BLV but not in naturally occurring caprine lymphosarcoma (5). The ovarian involvement was unusual and suggested a degree of tropism for these organs. This has not been previously reported in the literature.
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Treatment options for caprine lymphosarcoma are limited, due to the rapid progression of the disease and lack of response to symptomatic therapy. Temporary remission of lymphosarcoma has been reported in sheep given cyclophosphamide (6). Efficacy and cost effectiveness of this treatment in goats is questionable. The cause of caprine lymphosarcoma is unknown. Some researchers suggest the clinical findings associated with caprine lymphosarcoma are similar to those of enzootic bovine viral leukosis (5). Cattle present with signs of depression, anorexia, and weight loss, and rapidly deteriorate and die within 2 to 3 wk of the onset of clinical signs (6). Cattle are typically infected between the ages of 4 and 8 y, with an incubation period of 4 to 5 y (6). The youngest goat that has been reported with lymphosarcoma was 2-years old, indicating that the minimum incubation period is less than 2 y (2). There has been 1 reported case of a goat that developed lymphosarcoma 8 y postinoculation with BLV (5). There have been no reported cases of natural caprine lymphosarcoma due to BLV, so if caprine lymphosarcoma is viral in origin, the virus may be similar to BLV but oncogenically distinct (2). This case was noteworthy for the atypical clinical and pathological findings. The enlarged ovaries infiltrated with neoplastic lymphoid tissue and the exophthalmos due to retrobulbar masses were the most unique findings, demonstrating the clinical variability of caprine lymphosarcoma. Lymphosarcoma should be considered in any goat over 2 y of age that presents with depression, anorexia, weight loss, with or without peripheral lymph node enlargement, and potential ovarian enlargement. cvI
References 1. Smith MC. The reproductive anatomy and physiology of the female goat. In: Morrow DA, ed. Current Therapy in Theriogenology. 2nd ed. Philadelphia: WB Saunders, 1986: 577. 2. Craig DR, Roth L, Smith MC. Lymphosarcoma in goats. Compend Contin Educ Pract Vet 1986; 8: s 190-197. 3. Baker JC, Sherman DM. Lymphosarcoma in a Nubian goat. Vet Med Small Anim Clin 1982; 77: 557-559. 4. Matthews JG. Caprine tumours seen in a mixed practice. Goat Vet Soc J 1992; 13: 52-54. 5. Olson C, Kettmann R, Burny A, Kaja R. Goat lymphosarcoma from bovine leukemia virus. J Natl Cancer Inst 1981; 67: 671-673. 6. Olson C. Lymphosarcoma. In: Howard JL, ed. Current Veterinary Therapy: Food Animal Practice. Philadelphia: WB Saunders, 1981:
640-642.
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