J Vet Sci.  2007 Dec;8(4):423-425. 10.4142/jvs.2007.8.4.423.

Mammary fibroadenoma in a lamb

• Gulbahar M
• Guvenc T
• Yarim M
• Kabak YB
• Sozgen Y

• KMID: 1106224
• DOI: http://doi.org/10.4142/jvs.2007.8.4.423

Abstract

A fibroadenoma was diagnosed in the left udder of a 3-month-old female Chios lamb. No recurrence was observed after surgery. Grossly, the tumor had a whitishgray lobular appearance, and the lobules were interlaced with thin septa. Microscopically, the tumor was composed of proliferating fibroepithelial tissue, including differentiated ducts lined by whorls and interlacing bundles of abundant loose fibrovascular stroma. Immunohistochemistry revealed the ductal epithelium to be positive for pancytokeratin (AE1/AE3) and loose fibrovascular stroma was positive for vimentin and basal cells covering the ductal epithelium of alpha-smooth-muscle actin. Immunostaining for the estrogen and progesterone receptors was negative. A diagnosis of mammary fibroadenoma was made based on the histological and immunohistochemical findings.

Keyword

fibroadenoma; lamb; mammary gland; ovine; tumor

MeSH Terms

Animals
Female
Fibroadenoma/pathology/*veterinary
Keratins/metabolism
Mammary Glands, Animal/*pathology
Mammary Neoplasms, Animal/*pathology
Sheep
Sheep Diseases/*pathology
Vimentin/metabolism

Figure

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  Fig. 1 Macroscopic appearance of the tumor. A formalin fixed piece of the tumor showed a lobular pattern delineated by fibrous septa.

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  Fig. 2 (A) Ductal structures covered by abundant and thin cellular fibroblastic stroma. H&E stain, ×40. (B) Strong pancytokeratin expression in the ductal epithelium. ×160. (C) Positive immunostaining for vimentin in the spindle cells in the stroma. ×320. (D) Positive immunostaining for ASMA in the basal cells of the ducts suggestive myoepithelium. ×320. (B-D) SBPC method, DAB chromogen and Harris' hematoxylin counterstain.

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