Prevalence of Neoplasia in Llamas and Alpacas (Oregon State University, 2001–2006)

Abstract. A 13-year-old female llama was presented to the referring veterinarian for swelling and firmness of the right rear mammary gland, for a duration of 2 months, which had been unresponsive to antibiotics. A formalin-fixed wedge biopsy specimen from the affected quarter was submitted to Purdue University Animal Disease Diagnostic Laboratory for histopathology. Histopathologic examination revealed tubulopapillary acinar or solid nest-like clusters of neoplastic epithelial cells surrounded by whorls and sheets of proliferative myoepithelial cells. Histologic criteria for malignancy observed in neoplastic epithelial cells included marked cellular and nuclear atypia, high mitotic index, and numerous bizarre mitoses. The presence of osseous metaplasia in the proliferative mesenchymal component justified classification as a mixed tumor. Positive immunohistochemical staining of neoplastic epithelial cells with anticytokeratin antibody, and proliferative spindloid cells with antiviemtin and antismooth muscle actin antibodies supported the histopathologic diagnosis. The llama was in good health after about 1 year of initial presentation, and metastasis to regional lymph nodes was not reported. Mammary neoplasia is rare in camelids. To the authors' knowledge, this is the first report of a carcinoma in a mixed mammary tumor in a llama.

mentioning

confidence: 99%

Carcinoma in a Mixed Mammary Tumor in a Llama (Lama Glama)

Bangari

Stevenson

2007

“…11 It has been shown that lymphoma occurs at a younger age in alpacas when compared with llamas. 1,11,22 One case of subcutaneous lymphoma affected a young animal (1.5-year-old alpaca), whereas the other 2 cases of cutaneous lymphoma affected adult animals (9-year-old alpaca and 20-year-old llama). In other species, the clinical course of epitheliotropic CTCL can range from months to a few years 6 ; however, the small number of cases that have been reported in SACs restricts any ability to draw reliable conclusions with regards to the clinical course of this disease in camelids.…”

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confidence: 99%

“…A retrospective study describing the prevalence and types of neoplasia diagnosed in SACs for the Pacific Northwest observed that cutaneous and mucocutaneous neoplasms were the most common types of tumors diagnosed in the llama and alpaca; however, none of those cases were cutaneous lymphoma. 22 A 2010 review of skin disease in the alpaca reported a single case of subcutaneous lymphoma in a young alpaca. 19 Additionally, a larger study describing the immunophenotypic characterizations of 26 camelid malignant round cell tumors identified a single case of epitheliotropic cutaneous T-cell lymphoma (CTCL) in an aged llama.…”

mentioning

confidence: 99%

Pagetoid reticulosis (epitheliotropic cutaneous T-cell lymphoma) in an adult alpaca (Vicugna pacos)

Hasbach

Stern

2016

A 9-year-old, intact female alpaca ( Vicugna pacos) was presented for a second opinion with a 1-year history of nonpruritic, multifocal scaling and crusted cutaneous lesions, mainly involving skin on the face, axillae, and ventral abdomen. Clinical abnormalities were limited to the skin, and the alpaca was otherwise healthy. The initial veterinarian had examined the alpaca, found no evidence of ectoparasites with laboratory testing, and had tried several trial therapies including oral antibiotics, ivermectin, and topical use of betadine solution. At the time of presentation, the lesions had neither improved nor worsened with any attempted therapy, and multiple skin biopsies were collected. Histopathology and immunohistochemical staining findings were consistent with the pagetoid reticulosis type of cutaneous epitheliotropic T-cell lymphoma. Our report describes the clinical, histopathologic, and immunophenotypic features of pagetoid reticulosis epitheliotropic cutaneous T-cell lymphoma in an alpaca.

“…4,7,8,13 In the horse, melanomas most frequently occur in gray horses, and it is believed that a disturbance in melanin metabolism occurs during the graying process, leading to overproduction and accumulation of melanoblasts in the dermis. 4,13 Retrospective studies 2,9,12 reported the prevalence of neoplasia in the New World camelid to be 1.0-8.3%. To date, there has been 1 report of nonmetastatic intraocular melanoma in a 2-year-old female alpaca, 3 The malignant melanoma in the case here originated in the skin at the mucocutaneous junction of the left nares and was locally invasive, with metastasis to the regional lymph nodes and lung.…”

mentioning

confidence: 99%

Metastatic Malignant Melanoma in an Alpaca (Vicugna Pacos)

Mollat¹,

Gailbreath

Orbell

2009

Abstract. A case of malignant melanoma in a 7-year-old, intact, black, male Huacaya alpaca with a history of a chronic, nonhealing wound involving the left external nostril, weight loss, and inappetence is described. Malignant melanoma was diagnosed by histology of punch biopsy specimens from a mass on the maxilla associated with the nonhealing wound and from a mass in the submandibular region. The alpaca was humanely euthanized 10 days after the diagnosis on the basis of the poor prognosis and rapid clinical deterioration. At postmortem examination, the alpaca had an ulcerated, multilobulated, black pigmented mass (8.0 cm 3 6.0 cm 3 4.0 cm) that infiltrated the left rostral maxilla extending into the marrow space and into the left nasal cavity. Numerous, discrete, coalescing masses were present in the subcutaneous tissue of the submandibular area, peritracheal connective tissue, pericardium, and diaphragmatic parietal pleura and were disseminated throughout the pulmonary parenchyma. The masses were diffusely black on cut surface and exuded black pigment. Histologically, all masses were composed of spindloid to polygonal cells with indistinct cell borders and moderate amounts of cytoplasm that contained abundant fine, black granules (melanin), confirming metastasis of a primary mucocutaneous melanoma. To the authors' knowledge, this is the first report of a malignant melanoma involving bone in a New World camelid.Key words: Alpacas; camelid; malignant melanoma; metastatic; neoplasia.A 7-year-old, 56-kg, intact, black, male Huacaya alpaca presented with a 2-month history of a nonhealing wound on the left external nostril and a 10-day history of left submandibular and retropharyngeal swelling. Before referral, the alpaca had received local wound care and several courses of antibiotics without clinical improvement. The alpaca was housed in a paddock and fed a diet of grass hay and pellets. The animal was treated with anthelmintics and vaccinated (Clostridium perfringens types C and D and Clostridium tetani) regularly. No prior history of illness was reported by the owner. Physical examination revealed a normal temperature (38uC), heart rate (52 beats/min), and respiratory rate (32 breaths/min). The alpaca was thin, with a body condition score of 1.5 out of 5. The mucous membranes were moist, but capillary refill time could not be assessed because of dark pigmentation. Abnormalities were not noted on auscultation of the cardiovascular or respiratory system. Fewer than 2 first-compartment borborygmi were auscultated per minute (reference [ref.] range: 3-4 per min). A raised mass (6.0 cm 3 6.0 cm 3 3.0 cm) was present on the left cranial-lateral maxilla at the caudal aspect of the nares. The mass was firm, nonmovable, and intimately associated with the overlying black-pigmented skin, which was centrally ulcerated and firm with an irregular, bumpy surface and areas of mild hemorrhage. The mass appeared to extend into the nasal cavity in that the left nasal passage was completely obstructed by a black expansile mass si...