Epidemiology and incidence
Primary breast sarcomas accounting 0.0006% - 1% of all breast
malignancies and PBOS is far less common which accounts for about 4 -
12.5% of primary breast sarcomas (2,3).
There is a discrepancy among the reports in the literature as three
large studies of major referral centers over the same span of 40 to 50
years reported different incidences (2,3,4). Two
studies from Md Anderson (4) and Mayo clinic(3) reported one to two cases of primary breast
osteosarcoma among all sarcomas that they encountered in the same time
window (almost 40-50 years); Meanwhile, the third study from Armed
Forces Institute of Pathology in Washington DC has reported a much
higher incidence of 50 cases within the almost the same period of 40
years (2).
Although PBOS has been reported in a wide range of ages from 16 years
old teens (5) to 96 years old patients(6), it usually affects menopaused women in their
sixties to eighties (2,3,4).