Boyoung Park

Changes in metabolic syndrome and the risk of breast and endometrial cancer according to menopause in Korean women

OBJECTIVES: This study investigated how changes in metabolic syndrome (MetS) are associated with the subsequent risk of breast and endometrial cancer according to menopausal status.METHODS: This cohort study, using data from the National Health Insurance Service database, included women aged ≥40 years who underwent 2 biennial cancer screenings (2009-2010 and 2011-2012) and were followed up until 2020. Participants were grouped into MetS-free, MetS-recovery, MetS-development, and MetS-persistent groups. Menopausal status (premenopausal, perimenopausal, and postmenopausal) was assessed at 2 screenings. Cox proportional hazard regression was used to assess the association between MetS changes and cancer risk.RESULTS: In 3,031,980 women, breast and endometrial cancers were detected in 39,184 and 4,298, respectively. Compared with the MetS-free group, those who recovered, developed, or had persistent MetS showed an increased risk of breast cancer, with adjusted hazard ratios (aHRs) of 1.05, 1.05, and 1.11, respectively (p<0.005). MetS persistence was associated with an increased risk of breast cancer in postmenopausal women (aHR, 1.12, 95% confidence interval [CI], 1.08 to 1.16) but not in premenopausal or perimenopausal women. MetS persistence was associated with an increased risk of endometrial cancer in premenopausal, perimenopausal, and postmenopausal women, with aHRs of 1.41 (95% CI, 1.17 to 1.70), 1.59 (95% CI, 1.19 to 2.12), and 1.47 (95% CI, 1.32 to 1.63), respectively.CONCLUSIONS: Increased breast cancer risk was associated with recovered, developed, and persistent MetS in postmenopausal women. Meanwhile, increased endometrial cancer risk was found in obese women who recovered from MetS or persistently had MetS, regardless of menopausal status, when compared to MetS-free women.

Associations between obesity, metabolic syndrome, and endometrial cancer risk in East Asian women

This study investigated the associations between obesity, metabolic syndrome (MetS), the combination of these two components as a metabolic obesity phenotype, and endometrial cancer risk in East Asian women. A total of 6,097,686 cancer-free women aged 40-74 years who underwent the National Health Insurance Service health examination between 2009 and 2010 were included. Cancer incidence was identified using the healthcare utilization database. Associations between baseline obesity (body mass index <23 kg/m², 23-24.9 kg/m², ≥25 kg/m²), MetS, each component of MetS, MetS stratified by obesity status, combination of obesity and MetS, and endometrial cancer risk were investigated using hazard ratios (HRs). Obesity, each component of MetS, and MetS increased the endometrial cancer risk. After these factors were mutually adjusted for, the association did not change. When stratified by obesity, MetS and MetS components were not associated with endometrial cancer in normal-weight or overweight women. However, in obese women, MetS and MetS components increased the risk of endometrial cancer (HR=1.29; 95% confidence interval [CI]=1.20-1.39). Compared with normal-weight women without MetS, endometrial cancer risk was not increased in normal-weight women with MetS. Overweight women showed an increased risk of endometrial cancer irrespective of the presence of MetS (HR=1.37 and 1.38, respectively). The HR of obese women with MetS was higher than that of obese women without MetS (HR=2.18 and 1.75). The association between MetS and endometrial cancer was most prominent in obese women, suggesting that obese women with MetS would be more vulnerable to endometrial cancer.

Mammographic Breast Density and Risk of Ovarian Cancer in Korean Women

Abstract Background: This study aimed to investigate the potential association between mammographic breast density and ovarian cancer risk. Methods: This retrospective cohort study included women ≥40 years of age who underwent a mammography screening from 2009 to 2014. Breast density was assessed using the Breast Imaging-Reporting and Data System. The primary outcome was ovarian cancer development, and the cases were recorded until 2020. Cox proportional hazards regression was used to assess the association between breast density and ovarian cancer development. Subgroup analyses stratified by age, menopausal status, and body mass index (BMI) were conducted. Results: Of the 8,556,914 women included in this study, 9,246 ovarian cancer events were recorded during a median follow-up period of 10 years (interquartile range, 8.1–11.0 years). Compared with women with almost entirely fat density, those with scattered fibroglandular density, heterogeneous density, and extreme density had an increased risk of ovarian cancer with adjusted HRs of 1.08 [95% confidence interval (CI), 1.02–1.15], 1.16 (95% CI, 1.09–1.24), and 1.24 (95% CI, 1.15–1.34), respectively. The strongest association was observed in the ≥60 years age group; subgroup analysis indicated a significant increase in association between the higher-density category and ovarian cancer risk, regardless of BMI or menopausal status. Conclusions: Higher levels of breast density are associated with an increased risk of ovarian cancer. Impact: Breast density may have a relationship with ovarian cancer risk and could be used to assess future risk.