TY - JOUR
T1 - Adjuvant tamoxifen adherence in men with early-stage breast cancer
AU - Oke, Oluchi
AU - Niu, Jiangong
AU - Chavez-MacGregor, Mariana
AU - Zhao, Hui
AU - Giordano, Sharon H.
N1 - Publisher Copyright:
© 2021 American Cancer Society
PY - 2022/1/1
Y1 - 2022/1/1
N2 - Background: Most breast cancers (BCs) in men are hormone receptor–positive. Adjuvant tamoxifen is part of the standard treatment of these patients. Small, single-institution studies have suggested that men have high rates of discontinuing adjuvant endocrine treatment. The authors examined rates of tamoxifen discontinuation and medication adherence in a large population-based cohort of male patients with BC. Methods: In the Surveillance, Epidemiology, and End Results–Medicare database, male patients with invasive nonmetastatic BC, diagnosed between 2007 and 2013, who were ≥65 years old, had Part D coverage, and had tamoxifen prescriptions within 1 year of diagnosis were identified. Adherence was defined as a medication possession ratio of ≥80% among those patients who were filling tamoxifen prescriptions. Logistic regression model was used to assess predictors of tamoxifen adherence. Results: A total of 451 patients met eligibility criteria. The median age at diagnosis was 75 years. The median follow-up was 32.5 months. The rates of tamoxifen discontinuation were 15.8%, 24.3%, 31.3%, 36.9%, and 48.3% at 1, 2, 3, 4, and 5 years after diagnosis, respectively. Among the men who were still taking tamoxifen, the corresponding adherence rates were 76.9%, 73.6%, 68.7%, 64.8%, and 60.2%. In the adjusted model, significant predictors of lower adherence included residing in a high poverty area (odds ratio [OR], 0.77; 95% confidence interval [CI], 0.28-2.12) and a Charlson comorbidity score of ≥2 (OR, 0.46; 95% CI, 0.22-0.97). Conclusion: Older men with breast cancer have high rates of tamoxifen discontinuation, with 48% of all patients discontinuing tamoxifen before the end of year 5. Additionally, even among those patients continuing tamoxifen, a substantial number of patients are nonadherent. Further research should evaluate potentially modifiable reasons for treatment discontinuation and lack of adherence to tamoxifen.
AB - Background: Most breast cancers (BCs) in men are hormone receptor–positive. Adjuvant tamoxifen is part of the standard treatment of these patients. Small, single-institution studies have suggested that men have high rates of discontinuing adjuvant endocrine treatment. The authors examined rates of tamoxifen discontinuation and medication adherence in a large population-based cohort of male patients with BC. Methods: In the Surveillance, Epidemiology, and End Results–Medicare database, male patients with invasive nonmetastatic BC, diagnosed between 2007 and 2013, who were ≥65 years old, had Part D coverage, and had tamoxifen prescriptions within 1 year of diagnosis were identified. Adherence was defined as a medication possession ratio of ≥80% among those patients who were filling tamoxifen prescriptions. Logistic regression model was used to assess predictors of tamoxifen adherence. Results: A total of 451 patients met eligibility criteria. The median age at diagnosis was 75 years. The median follow-up was 32.5 months. The rates of tamoxifen discontinuation were 15.8%, 24.3%, 31.3%, 36.9%, and 48.3% at 1, 2, 3, 4, and 5 years after diagnosis, respectively. Among the men who were still taking tamoxifen, the corresponding adherence rates were 76.9%, 73.6%, 68.7%, 64.8%, and 60.2%. In the adjusted model, significant predictors of lower adherence included residing in a high poverty area (odds ratio [OR], 0.77; 95% confidence interval [CI], 0.28-2.12) and a Charlson comorbidity score of ≥2 (OR, 0.46; 95% CI, 0.22-0.97). Conclusion: Older men with breast cancer have high rates of tamoxifen discontinuation, with 48% of all patients discontinuing tamoxifen before the end of year 5. Additionally, even among those patients continuing tamoxifen, a substantial number of patients are nonadherent. Further research should evaluate potentially modifiable reasons for treatment discontinuation and lack of adherence to tamoxifen.
KW - adherence
KW - hormone receptor positive
KW - male breast cancer (MBC)
KW - medication possession ratio (MPR)
KW - tamoxifen
UR - http://www.scopus.com/inward/record.url?scp=85116068635&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85116068635&partnerID=8YFLogxK
U2 - 10.1002/cncr.33899
DO - 10.1002/cncr.33899
M3 - Article
C2 - 34597415
AN - SCOPUS:85116068635
SN - 0008-543X
VL - 128
SP - 59
EP - 64
JO - Cancer
JF - Cancer
IS - 1
ER -