title: A case of muscular hamartoma of the breast.
abstract: We describe a 74-year-old female presenting with a right breast mass. She had found the mass on self-examination. Physical examination revealed a 2.2 x 2.5 cm, firm, smooth, and mobile lump in the upper medial portion of the right breast. Mammography revealed a well marginated, oval-shaped, and isodense nodule. Calcification was not evident. On ultrasonography, the lesion was 17 x 18 x 9 mm and located 5 mm below the overlying skin. Excisional biopsy under local anesthesia was performed. The tumor was easily excised. Histopathologically, the lesion was composed of intersecting bundles of spindle-shaped smooth muscle cells, and involved peripheral ducts and fat tissue. Immunohistochemical staining showed positivity for alpha-smooth muscle actin (SMA), but was negative for S-100 protein, myoglobin, keratin, and vimentin. From these findings a muscular hamartoma of the breast, a rare subtype of hamartoma, was diagnosed.
authors.affiliation: Department of Surgery, Gihoku General Hospital, 1187-3 Takatomi, Takatomichou, Yamagatagun, Gifu 501-2105, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Takeuchi
authors.forename: Y
authors.initials: Y
authors.lastname: Kashiki
authors.forename: C
authors.initials: C
authors.lastname: Shibuya
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: F
authors.initials: F
authors.lastname: Kitamura
authors.forename: Y
authors.initials: Y
authors.lastname: Nagao
authors.forename: H
authors.initials: H
authors.lastname: Oota
authors.forename: N
authors.initials: N
authors.lastname: Yoshimi
mesh_terms: D000368:Aged; D001941:Breast Diseases / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006222:Hamartoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D008327:Mammography; D009130:Muscle, Smooth; D014463:Ultrasonography