Mammary hamartomas: an immunohistochemical study of ten cases.
Ten cases of breast hamartomas were reviewed; the patients' age ranged from 31 to 55 (mean 40.4, median 39). All cases presented with a palpable, sometimes tender, lump. The typical mammographic feature was a well defined, round to lens shaped, variable dense mass, occasionally surrounded by a thin radiolucent zone. All hamartomas were unilateral (4 in the right and 6 in the left breast, respectively) and no recurrence occurred after local excision. The tumor size ranged from 5 to 150 mm (mean 54 mm). Histologically all hamartomas were composed of a typical fibrous, adipose and glandular tissue combination. Immunohistochemically there was a strong positivity for cytokeratin and epithelial membrane antigen in the epithelial cells, a positive finding for vimentin and muscle-specific actin in stromal and myoepithelial cells, and for S-100 protein in myoepithelial cells. Vessels endothelial cells were immunoreactive for Factor VIII. Immunohistochemical analysis of hormone receptors completed on formaldehyde-fixed paraffin-embedded specimens, showed estrogen and progesterone receptors positivity in 9 cases and estrogen positive progesterone negative receptors in one case. In all cases the receptorial positivity was limited to the epithelial elements. These data revealed that 1) breast hamartoma is a benign, tumor-like lesion, histologically dissimilar from other lesions such as fibroadenoma and pseudoangiomatous hyperplasia; and 2) hamartoma tissue is influenced by hormones like the surrounding normal breast parenchyma.
Chiacchio
R
R
Dipartimento di Scienze Biomorfologiche e Funzionali, University of Medicine and Surgery, Federico II, Naples, Italy.
Panico
L
L
D'Antonio
A
A
Delrio
P
P
Bifano
D
D
Avallone
M
M
Pettinato
G
G
D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006222:Hamartoma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012189:Retrospective Studies
D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone