Background: There is uncertainty about the effectiveness of clinical breast examination (CBE) and conflicting recommendations regarding its usefulness as a screening tool for breast cancer. This paper provides an overview of systematic reviews that assessed the effectiveness of CBE as a 'stand-alone' screening modality for breast cancer compared to no screening and focused on its value in low- and middle-income countries (LMICs).
Methods: We searched MEDLINE, EMBASE, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews for systematic reviews reporting the effectiveness of CBE published prior to October 29, 2019. The main outcomes assessed were mortality and down staging. The AMSTAR 2 checklist was used to assess the methodological quality of the reviews including risk of bias.
Results: Eleven systematic reviews published between 1993 and 2019 were identified. There was no direct evidence that CBE reduced breast cancer mortality. Indirect evidence suggested that a well-performed CBE achieved the same effect as mammography regarding mortality despite its apparently lower sensitivity (40-69% for CBE vs 77-95% for mammography). Greater sensitivity was recorded among younger and Asian women. Moreover, CBE contributed between 17 and 47% of the shift from advanced to early stage cancer.
Conclusions: CBE merits attention from health system and service planners in LMICs where a national screening programme based on mammography would be prohibitively expensive. In particular, it is likely that considerable value would be gained from conducting implementation scientific research in countries with large numbers of Asian women and/or where younger women are at higher risk.
Registration: PROSPERO, registration number CRD42019126798 .
Keywords: Breast cancer; Clinical breast examination; LMICs; Systematic reviews.