Does Laterality in Breast Cancer still have the Importance to be Studied? A Meta-analysis of Patients with Breast Cancer

Abstract

Background: Breast cancer (BC) is one of the most common cancers in the world. Studies show that left-sided BC in pre and post-menopausal women leads to double the risk of worse morbidity and mortality and the reasons are uncertain. Finding the relationship between BC laterality and other possible risk factors can be advantageous for the prognosis of BC. Objective: This present study aimed to analyze the relationship between BC laterality and possible risk factors. Methods: A total of 6089 studies were screened. 23 studies from 1971 to 2021 met the inclusion criteria and were included in the meta-analysis. A pooled relative risk was generated via meta-analysis with a 95% confidence interval. Results: Left-side BC laterality was significant (p < 0.00001) in the women populations compared to the right side based on the pooled size with possible high-risk factors, including handedness, older women, body mass index, people with black skin, invasive type carcinoma, and estrogen receptor-negative BC. These findings suggest that there may be a complex interplay of genetic, environmental, and lifestyle factors that contribute to left-side BC laterality. Conclusion: Results suggest an increased rate of BC on the left side, with high-risk factors contributing to BC laterality, which may be useful in predicting prognosis. This study provides significant insights into the relationship between high-risk factors and BC laterality. By identifying potential risk factors associated with left-side BC, it may be possible to improve the ability to predict prognosis and develop more targeted treatment strategies. This information could be particularly useful for healthcare providers and patients, as it may guide decisions regarding screening, prevention, and treatment, ultimately improving patient outcomes and reducing the overall burden of BC.