The Impact of Breast Awareness on the Early Detection of Breast Cancer in Young Women: A Systematic Review.

Background: "Breast awareness" is a recommendation that women understand the symptoms of breast cancer and become familiar with the usual look and feel of their breasts. It is recommended for women of all ages in breast cancer screening guidelines around the world. The objective of this study was to assess the evidence for breast awareness by investigating its effect on breast cancer outcomes in women of pre-mammographic-screening age (under age 40), at average risk of breast cancer. Methods: A systematic review was performed using PRISMA methodology. Following the search, abstracts and full-text articles were assessed against eligibility criteria. Data were extracted into evidence tables, risk of bias was assessed, narrative synthesis was performed, and results were described. Eligible studies were original research studies assessing the impact of breast awareness on cancer outcomes (such as stage at diagnosis or survival) in women ≤40. Medline, PubMed, and Cochrane Library were searched. Results: After screening the 6,204 abstracts identified in the search, no studies meeting all eligibility criteria were found. Two partially eligible studies were identified. These met the intervention and outcomes criteria but included mixed-age cohorts that included but were not limited to women ≤40. These studies provided low-level (Level IV) evidence of moderate quality that there is some benefit (earlier stage at diagnosis and/or improved survival) of breast awareness in a mixed-age cohort that included some younger women. Conclusions: No studies evaluating the impact of breast awareness exclusively in young women were identified. Limited evidence of benefit of breast awareness was found. Guidelines that recommend breast awareness should be reviewed and qualified with an explanation that the evidence of benefit is weak. Women have limited screening options available to them for the early detection of breast cancer until they reach mammographic screening age. The study was registered on Prospero (ID: CRD42021279457).