Table 1 Learning points from this case report

1.

Primary breast sarcomas are rare tumours of the breast. They make up less than 0.1% of all breast tumours.

2.

Tumour development is either from normal breast tissue de novo, or as metaplastic differentiation of a primary benign or malignant breast lesion. Secondary deposits from a primary bone sarcoma occur only rarely, but need to be

3.

excluded clinically. Diagnosis is made by careful assessment of the histological specimen, together with immunohistochemical staining.

4.

Typically primary osteogenic breast cancer is usually considered a poor prognosis tumour, with high risk of disease recurrence and haematogeneous spread, most commonly to the lungs. Lymph node metastases do not occur.