Ethnic disparities in adverse events of chemotherapy for breast cancer: A scoping review.

Abstract

e18524 Background: Ethnic disparities may contribute to a higher symptom burden of adverse events following chemotherapy and poorer response to treatment for breast cancer. The objective was to examine the intra-group and inter-group ethnic differences in adverse effects experienced by Asian breast cancer patients undergoing chemotherapy with aromatase inhibitors or tamoxifen. Methods: A scoping review involving the Pubmed database was conducted. The search strategy included a combination of keywords and index terms related to Asians, breast cancer, CTCAE and treatment. Title, abstract and then full-text screening was performed by two reviewers. Primary research studies and systematic review articles involving female adults in peer-reviewed articles or grey literature records, of any design or date and published in English, were included. Descriptive statistics and charting was used to summarize the results. Results: Of 1765 abstracts retrieved and screened, 56 articles were ultimately included for analysis. Most articles (58.9%) studied the adverse events of tamoxifen. The majority of the studies involved Japanese patients (35.7%) followed by Chinese patients (19.6%) with an average of 8515 patients being studied per study. Only 2 studies were conducted in the US. Half the studies (50%) involved patients with TNM stage I breast cancer, postoperatively enrolled after BCS or mastectomy (71.4%). ER/PR status was reported in 58.9% of studies with an average of 494 patients being positive for either hormone receptor. HER-2 status was reported in 10 studies with an average of 53 positive HER-2 patients. 28.5% of studies involved patients with musculoskeletal adverse events following chemotherapy with aromatase inhibitors, commonly grade 3 or above (31.2%). These adverse events were arthralgia, fractures, osteoporosis or myalgia, affecting an average of 33.9% of patients in each study. 35.7% of studies involved patients with endocrinological adverse events following chemotherapy with tamoxifen. These adverse events involved menopausal symptoms, gynecological complications or endometrial cancer, affecting an average of 36.1% of patients in each study. Conclusions: Multi-level differences may contribute to the adverse events affecting Asian breast cancer patients undergoing chemotherapy with aromatase inhibitors or tamoxifen. Improving physician knowledge of ethnic disparities in adverse events occurring in Asian ethnic subgroups can help improve overall outcomes and patient adherence through a patient-centered approach.