title: Assessment of Breast Cancer Patients' Knowledge and Decisional Conflict Regarding Tamoxifen Use.
abstract: Breast cancer is the most common type of female cancer. Tamoxifen, a selective estrogen receptor modulator, is widely used to decrease breast cancer recurrence and mortality among patients. However, it also increases the risk of endometrial cancer. This study aimed to assess knowledge and decisional conflict regarding tamoxifen use. Between June and October 2014, breast cancer patients using tamoxifen were consecutively screened and requested to complete a survey including the EQ-5D, Satisfaction with Decision Scale (SWD), Decisional Conflict Scale (DCS), and a self-developed, 15-item questionnaire measuring tamoxifen-related knowledge. The study sample comprised 299 patients. The mean total knowledge score was 63.4 of a possible 100.0 (range, 13.3-93.3). While 73.9% of the participants knew that tamoxifen reduces the risk of breast cancer recurrence, only 57.9% knew that the drug increases endometrial cancer risk. A higher education level (≥ college) was associated with a higher, total knowledge score (β = 4.291; P = 0.017). A higher knowledge score was associated with a decreased DCS score (β = -0.366; P < 0.001). A higher SWD score was also associated with decreased decisional conflict (β = -0.178; P < 0.001). In conclusion, the breast cancer patients with higher levels of tamoxifen-related knowledge showed lower levels of decisional conflict regarding tamoxifen use. Clinicians should provide the exact information about tamoxifen treatment to patients, based on knowledge assessment results, so as to aid patients' decision-making with minimal conflict.
authors.affiliation: Department of Obstetrics and Gynecology, Seoul National University College of Medicine, Seoul, Korea. ; Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Se Ik
authors.initials: SI
authors.lastname: Kim
authors.affiliation: Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Yedong
authors.initials: Y
authors.lastname: Son
authors.affiliation: Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: So Yeun
authors.initials: SY
authors.lastname: Jun
authors.affiliation: Biometric Research Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Sooin
authors.initials: S
authors.lastname: Yun
authors.affiliation: Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Hyo Sook
authors.initials: HS
authors.lastname: Bae
authors.affiliation: Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea. ; Gynecologic Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Myong Cheol
authors.initials: MC
authors.lastname: Lim
authors.affiliation: Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: So-Youn
authors.initials: SY
authors.lastname: Jung
authors.affiliation: Biometric Research Branch, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Jungnam
authors.initials: J
authors.lastname: Joo
authors.affiliation: Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Eun Sook
authors.initials: ES
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000453:epidemiology; D032962:Consent Forms / Q000706:statistics & numerical data*; D003657:Decision Making; D016889:Endometrial Neoplasms / Q000139:chemically induced* / Q000453:epidemiology / Q000517:prevention & control; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006306:Health Surveys; D006801:Humans; D008875:Middle Aged; D010353:Patient Education as Topic / Q000706:statistics & numerical data*; D010358:Patient Participation / Q000706:statistics & numerical data; D015995:Prevalence; D056910:Republic of Korea; D018570:Risk Assessment; D013629:Tamoxifen / Q000009:adverse effects* / Q000627:therapeutic use*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D013629:Tamoxifen
keywords: Breast Neoplasms; Conflict; Decision Making; Knowledge; Patient Satisfaction; Tamoxifen