Type of breast cancer diagnosis, screening, and survival

Breast cancer screening is known to reduce mortality. In the present study, we analyzed the prevalence of breast cancers detected through screening, before and after introduction of an organized screening, and we evaluated the overall survival of these patients in comparison with women with an extrascreening imaging-detected breast cancer or those with palpable breast cancers.

We collected data about all women who underwent a breast operation for cancer in our department between 2001 and 2008, focusing on type of tumor diagnosis, tumor characteristics, therapies administered, and patient outcome in terms of overall survival, and recurrences. Data was analyzed by R (version 2.15.2), and P < .05 was considered significant.

Among the 2070 cases of invasive breast cancer we considered, 157 were detected by regional mammographic screening (group A), 843 by extrascreening breast imaging (group B: 507 by mammography and 336 by ultrasound), and 1070 by extrascreening breast objective examination (group C). The 5-year overall survival in groups A, B, and C were, respectively, 99% (95% CI, 98%-100%), 98% (95% CI, 97%-99%), and 91% (95% CI, 90%-93%), with a significant difference between the first 2 groups and the third (P < .05) and a trend between groups A and B (P = .081).

The diagnosis of invasive breast cancer with screening in our population resulted in a survival gain at 5 years from the diagnosis, but a longer follow-up is necessary to confirm this data.