Abstract PD4-05: Complementary and alternative medicine use and breast cancer chemotherapy initiation: The BQUAL study
Authors: H Greenlee, AI Neugut, L Falci, GC Hillyer, D Buono, JM Roh, IJ Ergas, ML Kwan, M Lee, WY Tsai, Z Shi, L Lamerato, JS Mandelblatt, LH Kushi, DL Hershman
Journal: Cancer Research (2016)

Abstract PURPOSE: Adjuvant therapy is associated with improved survival for women with breast cancer, but not all women who could benefit initiate treatment. Women's belief systems are related to treatment initiation. It has been hypothesized that complementary and alternative (CAM) use is associated with decreased initiation of standard oncology treatments because patients may be exploring alternative treatment approaches. However, there are limited data on the association between CAM use and cancer treatment initiation. We examined the association between CAM use and initiation of adjuvant breast cancer chemotherapy in a prospective cohort of early stage breast cancer patients. PATIENTS AND METHODS: Subjects participated in a multi-center prospective cohort study of women with early stage invasive breast cancer (n=1,156). National Comprehensive Cancer Network guidelines were used to define groups based on whether chemotherapy was indicated. Three subgroups were created: chemotherapy indicated for subjects &amp;lt;70 years, chemotherapy discretionary for subjects &amp;lt;70 years, and chemotherapy discretionary for subjects ≥70 years. CAM use was assessed based upon self-reported use of 5 CAM modalities, including vitamin/mineral supplements, herbal supplements, other over-the-counter natural products, mind-body based approaches, and body/energy-based treatments. Psychosocial factors potentially related to chemotherapy initiation were assessed. Multivariable logistic regression models evaluated the associations between CAM use and chemotherapy initiation, adjusted for demographic, clinical and psychosocial factors. RESULTS: Current CAM use was reported by 87% of women and 38% reporting current use of ≥3 modalities. The most commonly used CAM modalities were mind body therapies (63%) and other natural products (41%). In bivariate analyses, among women &amp;lt;70 years where chemotherapy was indicated, women who reported current use of vitamins/minerals or current use of all 5 CAM modalities were less likely to initiate chemotherapy compared to non-users (P&amp;lt;.0001), but this was not observed among women for whom chemotherapy was discretionary. Psychosocial factors were also associated with high levels of current CAM use in this group, including higher expectations of adverse effects from chemotherapy, more concerns about the physical effects of chemotherapy, lower beliefs in the benefits of chemotherapy, and lower positive decision balance while making chemotherapy decisions (all P&amp;lt;.05). Among women age &amp;lt;70 years for whom chemotherapy was indicated, 89% initiated treatment, and current use of all 5 CAM modalities was inversely associated with initiation in multivariable analyses adjusted for demographic and clinical factors (OR=0.08, CI: 0.02-0.32). The association remained after separately adjusting for psychosocial factors (all P&amp;lt;.05), except for positive decision balance, which was no longer statistically significant. CONCLUSIONS: High use of CAM was associated with decreased chemotherapy initiation among women with breast cancer for whom chemotherapy was indicated. It is important for oncologists to discuss CAM use with their patients, especially since high CAM use is associated with negative expectations and beliefs about chemotherapy. Citation Format: Greenlee H, Neugut AI, Falci L, Hillyer GC, Buono D, Roh JM, Ergas IJ, Kwan ML, Lee M, Tsai WY, Shi Z, Lamerato L, Mandelblatt JS, Kushi LH, Hershman DL. Complementary and alternative medicine use and breast cancer chemotherapy initiation: The BQUAL study. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD4-05.