Screening by mammography

 

Breast cancer screening is performed by mammography at special breast cancer screening units. Mammography is an X-ray examination with X-rays taken on both breasts at different angles. If the first mammogram is unclear or any abnormality is detected, the woman will be called for further assessment. The further assessments may include additional mammogram, ultrasonography, fine- and/or core-needle biopsy, galactography and pneumo-cystography. If the possibility of cancer can not be excluded, a biopsy with open surgery is performed.

An early phase cancer is detected by the screening programme most likely if it is detectable by mammography, but not yet palpable. If the cancer has a long preclinical phase it is more likely growing slowly, and its prognosis is better. It is likely that the impact of screening on the reduction of mortality is due to early detection of these slowly growing cancers.