Osteogenic Sarcoma of the Breast. A Case Report

Osseous metaplasia of the breast: diagnosis with stereotactic core biopsy

There are approximately 200 reported cases of breast tumors containing areas of bone. The majority of the neoplasms are sarcomas, phylloides tumors, or fibroadenomata. We present a case of osseous metaplasia mammographically detected by clustered heterogeneous calcifications. Stereotactic core biopsy revealed the presence of well-formed bone tissue without associated neolplasia. The case represents the first reported case of mammographically detected osseous metaplasia confirmed by core biopsy.

Primary osteogenic sarcoma of the breast: a clinicopathologic analysis of 50 cases

Extraskeletal osteosarcomas are rare. Few primary mammary osteosarcomas have been reported; many of these have been described in association with a biphasic tumor. Fifty pure osteosarcomas of the breast, diagnosed between 1957 and 1995, were reviewed after excluding those of biphasic origin. The absence of epithelial differentiation was confirmed using a panel of immunohistochemical markers in 32 cases and using ultrastructural evaluation in an additional four cases. Tumors occurred in 49 women and one man; age ranged from 27 to 89 years (median, 64.5 years). One patient received radiotherapy for ipsilateral breast carcinoma 9 years before presentation. Patients were treated by excisional biopsy (n = 13), tylectomy (n = 5) or mastectomy (n = 32). All axillary nodes, dissected in 20 patients, were free of tumor. One patient had extramammary spread at diagnosis. The neoplasms were 1.4 cm to 13.0 cm (mean, 4.6 cm), and 60% were grossly circumscribed. Tumors were classified as fibroblastic (n = 28), osteoclastic (n = 14), or osteoblastic (n = 8). Of 39 patients with available follow-up information, locally recurrent (n = 11) and metastatic (n = 15) disease developed in 23 (59%) at a mean of 10.5 and 14.5 months from diagnosis. Eight (73%) patients in whom local recurrence developed were treated with excisional biopsy or tylectomy; of these, seven had a positive margin. Sixteen (41%) patients died of disease at a mean of 17.1 months, within 20 months of onset of metastases, most commonly to the lung. Mammary osteosarcomas are aggressive tumors with a propensity for blood-borne rather than lymphatic spread. Total excision without axillary dissection is advised.

Primary osteosarcoma of the breast

A case of primary osteosarcoma of the breast in an 83 year-old woman was studied by using a large immunohistochemical panel of antibodies. Tumor cells were stained intensely for vimentin, and focally for alpha-1-antitrypsin. No immunoreactivity was detected for cytokeratin. The absence of an epithelial component excludes a metaplastic carcinoma. The multinucleated giant cells stained strongly for KP-1 antibody, indicating a histiocytic nature. The question is raised whether osteosarcoma of the breast is a malignant tumor de novo, or develops by transformation of a fibroadenoma.