A new study has found that the mammogram x-ray scan picks up just 56 per cent of early-stage breast lesions in women classified as being in a high-risk group.
Most breast cancers begin with non-invasive cancerous cells in the milk ducts which, if detected and treated early enough, can prevent the disease progressing. Lead researcher Christiane Kuhl at the University of Bonn commented: "If you picked up all cases of ductal carcinoma in situ (DCIS) you would prevent virtually all cases of breast cancer."
The researchers also discovered that magnetic resonance imaging scans (MRI) - which is currently used for brain scans - was a more effective test, picking up 92 per cent of early-stage cancers. Currently, only young woman at high-risk of breast cancer are offered the more expensive MRI scan.
The mammogram is the standard screening test for woman aged between 50 and 70 years.
(Source: The Lancet, 2007; 370: 485-92).