TY - JOUR
T1 - Incidence of hypothyroidism after treatment for breast cancer
T2 - A Korean population-based study
AU - Park, Jongmoo
AU - Kim, Choongrak
AU - Ki, Yongkan
AU - Kim, Wontaek
AU - Nam, Jiho
AU - Kim, Donghyun
AU - Park, Dahl
AU - Jeon, Hosang
AU - Kim, Dong Woon
AU - Joo, Ji Hyeon
N1 - Publisher Copyright:
© 2022 Park et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
PY - 2022/6
Y1 - 2022/6
N2 - This Korean population-based study aimed to describe the patterns of hypothyroidism after adjuvant radiation therapy (RT) in patients with breast cancer. The Korean Health Insurance Review and Assessment Service database was searched for patients with invasive breast carcinomas. We calculated the cumulative incidence and incidence rates per 1,000 person-years of subsequent hypothyroidism and compared them using the log-rank test and the Cox proportional hazards model. Between 2007 and 2018, 117,135 women diagnosed with breast cancer with a median follow-up time of 4.6 years were identified. The 8-year incidence of hypothyroidism was 9.3% in patients treated with radiation and 8.6% in those treated without radiation (p = 0.002). The incidence rates per 1,000 person-years in the corresponding treatment groups were 6.2 and 5.7 cases, respectively. The hazard ratio (HR) in patients receiving RT was 1.081 (95% confidence interval [CI], 1.013–1.134; p = 0.002). After mastectomy, RT showed a trend toward a higher risk of hypothyroidism (HR = 1.248; 95% CI, 0.977–1.595; p = 0.076). Our study provides one of the largest population-based data analyses regarding the risk of hypothyroidism among Korean patients with breast cancer. The adjusted risk for patients treated with RT exceeded that for patients with breast cancer treated without RT. The effect was evident immediately after treatment and lasted up to approximately 9 years.
AB - This Korean population-based study aimed to describe the patterns of hypothyroidism after adjuvant radiation therapy (RT) in patients with breast cancer. The Korean Health Insurance Review and Assessment Service database was searched for patients with invasive breast carcinomas. We calculated the cumulative incidence and incidence rates per 1,000 person-years of subsequent hypothyroidism and compared them using the log-rank test and the Cox proportional hazards model. Between 2007 and 2018, 117,135 women diagnosed with breast cancer with a median follow-up time of 4.6 years were identified. The 8-year incidence of hypothyroidism was 9.3% in patients treated with radiation and 8.6% in those treated without radiation (p = 0.002). The incidence rates per 1,000 person-years in the corresponding treatment groups were 6.2 and 5.7 cases, respectively. The hazard ratio (HR) in patients receiving RT was 1.081 (95% confidence interval [CI], 1.013–1.134; p = 0.002). After mastectomy, RT showed a trend toward a higher risk of hypothyroidism (HR = 1.248; 95% CI, 0.977–1.595; p = 0.076). Our study provides one of the largest population-based data analyses regarding the risk of hypothyroidism among Korean patients with breast cancer. The adjusted risk for patients treated with RT exceeded that for patients with breast cancer treated without RT. The effect was evident immediately after treatment and lasted up to approximately 9 years.
UR - http://www.scopus.com/inward/record.url?scp=85132080434&partnerID=8YFLogxK
U2 - 10.1371/journal.pone.0269893
DO - 10.1371/journal.pone.0269893
M3 - Article
C2 - 35709221
AN - SCOPUS:85132080434
SN - 1932-6203
VL - 17
JO - PLoS ONE
JF - PLoS ONE
IS - 6 June
M1 - e0269893
ER -
