Annual or biennial mammography screening for women at a higher risk with a family history of breast cancer : prognostic indicators of screen-detected cancers in New South Wales, Australia

This study examined whether offering annual mammography screening for women with the risk factor of a family history of breast cancer resulted in more favourable prognostic indicators of diagnosed cancers than the usual approach of biennial screening. The study involved women aged 50ââ"šÂ¬Ã¢â‚¬Å“69 years with a family history of breast cancer, defined as having C1 first-degree relative diagnosed with breast cancer, who were diagnosed with a screen-detected invasive breast cancer between 1998 and 2004 in BreastScreen New South Wales (n = 590). The women were grouped according to whether they screened in an area offering annual screening to women with a family history, or were offered the standard biennial screening. The odds of having favourable tumor size, grade, and nodal status prognosis were compared between these screening groups using logistic regression. A comparison group of women without a family history, all offered biennial screening, was also evaluated based on the same area groupings to examine whether any differences were due to the area, rather than the screening interval policy. Women with a family history who were offered annual screening at BreastScreen NSW were significantly more likely than those who were offered biennial screening to be diagnosed with a tumor B20 mm in size (adjusted odds ratio (AOR) = 1.91, 95% CI: 1.21ââ"šÂ¬Ã¢â‚¬Å“3.02), and to have a node-negative tumor (AOR = 1.61, 95% CI: 1.03ââ"šÂ¬Ã¢â‚¬Å“2.50). There were also significantly higher odds of being diagnosed with tumors B15 mm (p