New research presented today at the 6th European Breast Cancer Conference, Berlin, suggests that the risk of developing breast cancer after a prophylactic mastectomy is much lower than originally thought.

Those found to carry the BRCA gene mutation, predisposing them to hereditary breast cancer, often choose to have both breasts removed before any sign of cancer due to the high risk - 85%.

This procedure was previously thought to lower the risk of breast cancer to 5%, but Dr. Reine Kaas, from the Surgical Department of the Netherlands Cancer Institute says that the resulting risk is actually less than 1%.

Dr. Kaas and her team studied the effects of prophylactic mastectomy in 250 patients who were BRCA carriers. Only one was later diagnosed with a breast cancer, thought to be because the axillary tail (a small part of the breast that extends towards the armpit) had not been completely removed.

"Our epidemiologists are investigating how many breast cancers are avoided up to the age of 80 in these women," she says. "But on current evidence we can safely state that continued follow-up, which can be costly as well as stressful for the patient, is not warranted in patients who have had a prophylactic mastectomy. Surveillance in those BRCA carriers who do not opt for mastectomy has to start at an early age, and the frequent visits to the doctor and the many examinations which need to be undertaken regularly can be a source of great stress for many women:

Monthly breast self-examination, bi-annual clinical breast examination by a physician and annual mammography plus breast MRI, means that around half of the BRCA carriers simply opt for prophylactic mastectomy.