A Simple Ductal Mammary Papilloma in a Male Maned Wolf (Chrysocyon Brachyurus)

Abstract

Abstract. A 1-cm-diameter nodule was identified in the left inguinal mammary gland of a 9-year-old male maned wolf (Chrysocyon brachyurus). The mass was surgically excised and examined histologically. Microscopically, the neoplasm consisted of papillary proliferations of epithelial cells on well-defined fibrovascular stalks. A myoepithelial layer was located between the single layer of epithelial cells and the fibrovascular stalk. This histologic appearance was compatible with a diagnosis of simple ductal mammary papilloma. Immunohistochemical staining was positive for p63, cytokeratins AE1/AE3, and estrogen receptors. The clinical and histologic observations in the present case indicate that male maned wolves may develop mammary tumors that are similar to those observed in domestic dogs and humans.

Histologic, Immunohistochemical, and Clinical Features of 27 Mammary Tumors in 18 Male Dogs

“…Demonstration of a continuous layer of myoepithelium between the neoplastic mammary epithelium and the stroma indicates that the neoplastic epithelium has not invaded the stroma and, thus, correlates with benignancy. 2,14 Myoepithelial cells can be difficult to identify in HE-stained sections; therefore, immunohistochemical markers for calponin and p63 were used to demonstrate their presence. Calponin is a smooth muscle-specific protein that has been shown to be a sensitive marker of normal and neoplastic myoepithelium in the canine mammary gland; however, other cell types (stromal myofibroblasts and chondroblasts) can also stain positively.…”

Tubulopapillary carcinoma of the mammary gland in a maned wolf (Chrysocyon brachyurus): histopathological and immunophenotypical analysis

“…Smooth muscle alpha actin, CK5 and p63 antibodies were used to highlight canine mammary gland myoepithelial cells (Ramalho et al, 2006). Nuclear myoepithelial staining for p63 has been utilized in a male maned wolf benign mammary tumor, and the non-infiltrative nature of the tumor was observed (Cassali et al, 2009). In this paper, myoepithelial cell smooth muscle alpha actin reactivity at the epithelialstromal junction demonstrated myoepithelium integrity loss and microinvasive areas, confirming an infiltrative tubulopapillary carcinoma.…”

“…Neoplasms have been described in captive maned wolves (Munson and Montali, 1991;McNulty et al, 2000;Cracknell et al, 2009). Until now, only one case of a male maned wolf mammary neoplasm has been described (Cassali et al, 2009). This is the first report of a malignant mammary tumor in a female maned wolf.…”

“…Mammary tumors have been reported previously in a European pine marten (Martes martes) (Williams et al, 1989), Blackfooted ferrets (Mustela nigripes) (Carpenter et al, 1980), Mexican gray wolf (Canis lupus baileyi) (Federico et al, 2010), red fox from Austria (Vulpes vulpes) ( Janovsky and Steineck, 1999), Guinea pig (Cavia porcellus) (Suárez-Bonnet et al, 2009) and male Maned wolf (Chrysocyon brachyurus) (Cassali et al, 2009). This is the first report that describes pathological and immunophenotyping findings of a female maned wolf tubulopapillary carcinoma of the mammary gland.…”

COMPLEX CARCINOMA OF THE MAMMARY GLAND IN A FREE-LIVING JAPANESE RACCOON DOG (NYCTEREUTES PROCYONOIDES VIVERRINUS)

“…10 On the other hand, mammary-gland tumors are rarely observed in wild or exotic animals. 1,2,4,5,7,15,17 There have been a few reports of the mammary-gland tumors in nondomestic carnivores. 1,2,4,5,7,11,15,17 Especially in exotic Canidae, there have been few case reports, e.g., adenocarcinoma of the mammary gland in a free-ranging red fox (Vulpes vulpes); 7 mixed mammary tumor composed of infiltrating ductal carcinoma with centers of mucinous, epidermoid, and chondrosarcoma (chondrosarcoma carcinoma) in a captive Mexican gray wolf (Canis lupus baileyi); 4 and simple ductal mammary papilloma 2 and tubulopapillary carcinoma of the mammary gland 5 in captive maned wolves (Chrysocyon brachyurus).…”