Authors' objectives:

This report aims to assess the available evidence on the benefits of mammography screening.

Authors' recommendations: - Mammography screening in the age group of 50-69 years reduces breast cancer mortality. - The scientific documentation has some weaknesses and the estimated relative risk of reduction in mortality is in the order of 6% to 27%. Other documentation reports a risk reduction of 20-25%. - The effect in the age group 40-49 years is less and uncertain with an even weaker evidence. - Mammography screening does not protect against development of breast cancer between the screening rounds. Interval cancer is a reality and more than on fifth of the women who get the diagnosis breast cancer, get their cancer diagnosis between the screening rounds. The women must have knowledge of this phenomenon. - There is a cumulative risk of false positive mammograms for each screening round, and thereby a need for new mammograms and other examinations (included biopsies or surgery). - It is uncertain if all ductal carcinomas in situe (DCISs) need treatment. The problem is that one does not know which DCISs needs treatment and which ones do not.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.nokc.no/

Year Published: 2002

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Norway

Organisation Name: Norwegian Institute of Public Health

Contact Address: Universitetsgata 2, Postbox 7004 St. Olavs plass, NO-0310 Oslo NORWAY. Tel: +47 23 25 50 00; Fax: +47 23 25 50 10;

Contact Name: Berit.Morland@nokc.no, dagny.fredheim@nokc.no

Contact Email: Berit.Morland@nokc.no, dagny.fredheim@nokc.no

Copyright: The Norwegian Knowledge Centre for the Health Services