Clinical and Histopathological Diagnosis of Superficial Angiomyxoma in a Pregnant Holstein Heifer

Myxomas are tumors of soft tissue with fibroblast origin characterized by their remarkable myxoid matrix rich in mucopolysaccharides. Here, we report the clinical and histopathological characteristics of angiomyxoma in a pregnant two-year-old- Holstein heifer. A notable and palpable mass was found in the right teat of the front quarter with no ulcer or infection. In the gross examination, the mass was soft, solitary, well-circumscribed, and unencapsulated grey to white. The mass was removed by local anesthesia and surgery. Histopathology dominantly demonstrated an unencapsulated and well-differentiated proliferation of spindle to stellate-shaped fibroblasts loosely arranged in a myxoid matrix associated with admixed numerous thin-walled blood vessels. Cellularity was low, mitoses were rare, and there was little cytological atypia. No evidence of hemorrhage, edema, necrosis, and acute inflammation were observed on the tissue sections. Immunohistochemical examinations were positive for S100 and vimentin markers. The surgical removal of the tumor mass with sedation and local anesthesia was suggested as the treatment of choice for optimal recovery.