Medline ® Abstract for Reference 62
of 'Screening for breast cancer: Evidence for effectiveness and harms'
Regular self-examination or clinical examination for early detection of breast cancer.
Kösters JP, Gøtzsche PC
Cochrane Database Syst Rev. 2003;
BACKGROUND: Breast self-examination and clinical breast examination have been promoted for many years as general screening methods to diagnose breast cancer at an earlier stage in order to decrease morbidity and or mortality. The possible benefits and harms remain unclear.
OBJECTIVES: To determine whether screening for breast cancer by regular self-examination or clinical breast examination reduces breast cancer mortality and morbidity.
SEARCH STRATEGY: The Cochrane Library and Medline were searched for randomised trials; date of last search October 2002. The specialised register maintained by the Cochrane Breast Cancer Group was searched.
SELECTION CRITERIA: Randomised clinical trials, including cluster randomised trials.
DATA COLLECTION AND ANALYSIS: Decisions on which trials to include were taken independently by the reviewers based on the methods of trial. Disagreements were resolved by discussion. Intention to treat analyses were conducted using a fixed effect model with 95% confidence intervals.
MAIN RESULTS: Two large population-based studies (388,535 women) from Russia and Shanghai that compared breast self-examination with no intervention were included. There was no statistically significant difference in breast cancer mortality, relative risk 1.05 (95% confidence interval (CI) 0.90 to 1.24) (587 deaths in total). In Russia, more cancers were found in the breast self-examination group than in the control group (relative risk 1.24, 95% CI 1.09 to 1.41), while this was not the case in Shanghai (relative risk 0.97, 95% CI 0.88 to 1.06). Almost twice as many biopsies (3406) with benign results were performed in the screening group compared to the control group (1856), relative risk 1.89, 95% CI 1.79 to 2.00.
REVIEWER'S CONCLUSIONS: Data from two large trials do not suggest a beneficial effect of screening by breast self-examination whereas there is evidence for harms. There were no randomised trials of clinical breast examination. At present, breast self-examination cannot be recommended.
Nordic Cochrane Centre, Rigshospitalet, Dept. 7112, Blegdamsvej 9, 2100 CopenhagenØ, Denmark. firstname.lastname@example.org