Associations between breast cancer risk factors and mammographic breast density in a large cross-section of Korean women.

BACKGROUND: We investigated the association between established risk factors for breast cancer and mammographic breast density in Korean women. METHODS: This large cross-sectional study included 8 460 928 women aged >40 years, who were screened for breast cancer between 2009 and 2018. Breast density was assessed using the Breast Imaging Reporting and Data System. This study used multiple logistic regression analyses of age, BMI, age at menarche, menopausal status, menopausal age, parity, breastfeeding status, oral contraceptive use, family history of breast cancer, physical activity, smoking, drinking and hormone replacement therapy use to investigate their associations with mammographic breast density. Analyses were performed using SAS software. RESULTS: Of 8 460 928 women, 4 139 869 (48.9%) had nondense breasts and 4 321 059 (51.1%) had dense breasts. Factors associated with dense breasts were: earlier age at menarche [<15 vs. ≥15; adjusted odds ratio (aOR), 1.18; 95% confidence interval (CI), 1.17-1.18], premenopausal status (aOR, 2.01; 95% CI, 2.00-2.02), later age at menopause (≥52 vs. <52; aOR, 1.23; 95% CI, 1.22-1.23), nulliparity (aOR, 1.64; 95% CI, 1.63-1.65), never breastfed (aOR, 1.23; 95% CI, 1.23-1.24) and use of hormone replacement therapy (aOR, 1.29; 95% CI, 1.28-1.29). Women with a higher BMI and the use of oral contraceptives were more likely to have nondense breasts. CONCLUSION: Lower BMI, reproductive health and behavioral factors were associated with dense breasts in Korean women. Additional research should investigate the relationship between mammographic breast density, breast cancer risk factors and breast cancer risk.

Family history of breast cancer, mammographic breast density and breast cancer risk: Findings from a cohort study of Korean women.

BACKGROUND: This study investigated whether the association between family history of breast cancer in first-degree relatives and breast cancer risk varies by breast density. METHODS: Women aged 40 years and older who underwent screening between 2009 and 2010 were followed up until 2020. Family history was assessed using a self-reported questionnaire. Using Breast Imaging Reporting and Data System (BI-RADS), breast density was categorized into dense breast (heterogeneously or extremely dense) and non-dense breast (almost entirely fatty or scattered areas of fibro-glandular). Cox regression model was used to assess the association between family history and breast cancer risk. RESULTS: Of the 4,835,507 women, 79,153 (1.6%) reported having a family history of breast cancer and 77,238 women developed breast cancer. Family history led to an increase in the 5-year cumulative incidence in women with dense- and non-dense breasts. Results from the regression model with and without adjustment for breast density yielded similar HRs in all age groups, suggesting that breast density did not modify the association between family history and breast cancer. After adjusting for breast density and other factors, family history of breast cancer was associated with an increased risk of breast cancer in all three age groups (age 40-49 years: aHR 1.96, 95% confidence interval [CI] 1.85-2.08; age 50-64 years: aHR 1.70, 95% CI 1.58-1.82, and age ≥65 years: aHR 1.95, 95% CI 1.78-2.14). CONCLUSION: Family history of breast cancer and breast density are independently associated with breast cancer. Both factors should be carefully considered in future risk prediction models of breast cancer.

Prognostic Value of Post-diagnosis Health-Related Quality of Life for Overall Survival in Breast Cancer: Findings from a 10-Year Prospective Cohort in Korea.

PURPOSE: We aimed to evaluate health-related quality of life (HRQOL) at 1-year post-diagnosis in breast cancer (BC) patients and its association with overall survival using data from the National Cancer Center Hospital. MATERIALS AND METHODS: Data of a BC cohort were first obtained between 2004 and 2006 and followed up. HRQOL was assessed using EORTC QLQ-C30 and BC specific module QLQ-BR23 few days after diagnosis and 1 year after that. We examined and compared the difference in the two HRQOL scores measured for each patient by the patient's current survival status. The Cox proportional hazards model was fitted to evaluate the impact of HRQOL on survival, with adjustment for baseline HRQOL and other factors. RESULTS: Of 299 enrolled patients, 206 responded at 1-year post-diagnosis (80.6%) and were followed up for 11.6 years on average. At 1-year post-diagnosis, survivors had better HRQOL scores than those who died, although their health status was similar at baseline. Survivors reported significant increase 1 year after diagnosis in global health status and emotional scales. Between the groups, functional scales such as physical, role, and emotional were significantly different. Functional scales, including physical (adjusted hazard ratio [aHR], 0.70), role (aHR, 0.68), emotional (aHR, 0.72), and symptom scales, including fatigue (aHR, 1.34), dyspnea (aHR, 1.29), appetite loss (aHR, 1.24) were significantly associated with overall survival. Patients who were less worried about future health had favorable survival (aHR, 0.83). CONCLUSION: Besides treatment-related symptoms, non-medical aspects at 1-year post-diagnosis, including functional well-being and future perspective, are predictive of long-term survival. Intervention to enhance physical, role, and emotional support for women soon after their BC diagnosis might help to improve disease survival outcomes afterwards.

Socioeconomic Inequalities in Cervical and Breast Cancer Screening among Women in Korea, 2005-2015.

PURPOSE: Consistent evidence indicates that cervical and breast cancer screening rates are low among socioeconomically deprived women. This study aimed to assess trends in cervical and breast cancer screening rates and to analyze socioeconomic inequalities among Korean women from 2005 to 2015. MATERIALS AND METHODS: Data from the Korean National Cancer Screening Survey, an annual nationwide cross-sectional survey, were utilized. A total of 19910 women were finally included for analysis. Inequalities in education and household income status were estimated by slope index of inequality (SII) and relative index of inequality (RII), along with calculation of annual percent changes (APCs), to show trends in cancer screening rates. RESULTS: Cervical and breast cancer screening rates increased from 54.8% in 2005 to 65.6% in 2015 and from 37.6% in 2005 to 61.2% in 2015, respectively. APCs in breast cancer screening rates were significant among women with higher levels of household income and education status. Inequalities by household income in cervical cancer screening uptake were observed with a pooled SII estimate of 10.6% (95% CI: 8.1 to 13.2) and RII of 1.4 (95% CI: 1.3 to 1.6). Income inequalities in breast cancer screening were shown to gradually increase over time with a pooled SII of 5.9% (95% CI: 2.9 to 9.0) and RII of 1.2 (95% CI: 0.9 to 1.3). Educational inequalities appeared to diminish over the study period for both cervical and breast cancer screening. CONCLUSION: Our study identified significant inequalities among socioeconomically deprived women in cervical and breast cancer screening in Korea. Especially, income-related inequalities were greater than education-related inequalities, and these were constant from 2005 to 2015 for both cervical and breast cancer screening.

Socioeconomic Inequalities in Colorectal Cancer Screening in Korea, 2005-2015: After the Introduction of the National Cancer Screening Program.

PURPOSE: This study aimed to investigate inequalities in colorectal cancer (CRC) screening rates in Korea and trends therein using the slope index of inequality (SII) and relative index of inequality (RII) across income and education groups. MATERIALS AND METHODS: Data from the Korean National Cancer Screening Survey, an annually conducted, nationwide cross-sectional survey, were utilized. A total of 17174 men and women aged 50 to 74 years were included for analysis. Prior experience with CRC screening was defined as having either a fecal occult blood test within the past year or a lifetime colonoscopy. CRC screening rates and annual percentage changes (APCs) were evaluated. Then, SII and RII were calculated to assess inequality in CRC screening for each survey year. RESULTS: CRC screening rates increased from 23.4% in 2005 to 50.9% in 2015 (APC, 7.8%; 95% CI, 6.0 to 9.6). Upward trends in CRC screening rates were observed for all age, education, and household income groups. Education inequalities were noted in 2009, 2014, and overall pooled estimates in both indices. Income inequalities were inconsistent among survey years, and overall estimates did not reach statistical significance. CONCLUSION: Education inequalities in CRC screening among men and women aged 50 to 74 years were observed in Korea. No apparent pattern, however, was found for income inequalities. Further studies are needed to thoroughly outline socio-economic inequalities in CRC screening.

Socioeconomic Inequalities in Stomach Cancer Screening in Korea, 2005-2015: After the Introduction of the National Cancer Screening Program.

PURPOSE: This study aimed to investigate socioeconomic inequalities in stomach cancer screening in Korea and trends therein across income and education groups. MATERIALS AND METHODS: Data from the Korean National Cancer Screening Survey, a nationwide cross-sectional survey, were utilized. A total of 28913 men and women aged 40 to 74 years were included for analysis. Prior experience with stomach cancer screening was defined as having undergone either an endoscopy or gastrointestinal series within the past two years. The slope index of inequality (SII) and relative index of inequality (RII) were evaluated to check inequalities. RESULTS: Stomach cancer screening rates increased from 40.0% in 2005 to 74.8% in 2015, with an annual percent change of 5.8% [95% confidence interval (CI) 4.2 to 7.5]. Increases in stomach cancer screening rates were observed for all age, education, and household income groups. Inequalities in stomach cancer screening were noted among individuals of differing levels of education, with a pooled SII estimate of 6.14% (95% CI, 3.94 to 8.34) and RII of 1.26 (95% CI, 1.12 to 1.40). Also, income-related inequalities were observed with an SII of 6.93% (95% CI, 4.89 to 8.97) and RII of 1.30 (95% CI, 1.17 to 1.43). The magnitude of inequality was larger for income than for education. CONCLUSION: Both education and income-related inequalities were found in stomach cancer screening, despite a continuous increase in screening rate over the study period. Income-related inequality was greater than education-related inequality, and this was more apparent in women than in men.

Increasing Trend in Hospital Deaths Consistent among Older Decedents in Korea: A Population-based Study Using Death Registration Database, 2001-2014.

BACKGROUND: With improvement in hospice palliative care services and long-term care, Republic of Korea (hereafter South Korea) has recorded significant changes in places of death (e.g., hospital, home), especially among older adults. Over the last few decades, the most common places of death in South Korea were hospitals. However, Koreans, especially older adults, reportedly prefer to receive terminal care and eventually die at home. This study was conducted to investigate trends in places of death among older Korean adults and factors associated therewith. METHODS: Data were obtained from the Korean Death Registration Database maintained by the National Statistical Office. Decedents who died after the age of 65 years from 2001 to 2014 were included in the analysis. For descriptive analysis, proportions of places of death were analyzed and were used to plot graphs for visualizing trends during 13-year period. Logistic regression model was used to evaluate factors associated with places of death (hospital versus home). RESULTS: Two million three hundred fifty eight thousand two hundred eleven older adult decedents were included in final analysis. Hospitals were the most common places of death (57.82%), followed by homes (32.12%). Dying at social welfare facilities was rare (2.61%). A gradual increase in hospital deaths (31.38% in 2001 to 75.30% in 2014) and a subsequent decrease in home deaths (60.44% to 15.95% over the same period) were noted. Hospital deaths were more likely for younger patients (ORs 1.28, 95% CI 1.27-1.29), females (ORs 1.28, 95% CI 1.27-1.29), and single/divorced or widowed individuals (ORs 1.77, 1.49 and 1.03 respectively). A higher education level and living in urban areas were strongly associated with a higher likelihood of dying in a hospital. CONCLUSION: Over the study period, there was a consistent increasing trend in hospital deaths in South Korea. Trends in place of death and factors associated therewith should be more intensely investigated and monitored. Resources and facilities should be increased to fulfill end-of-life care preferences and the needs of an increasingly older population in South Korea.

Do Korean Doctors Think a Palliative Consultation Team Would Be Helpful to Their Terminal Cancer Patients?

PURPOSE: Hospice and palliative care services (HPC) are not commonly utilized in Korea; however, palliative care teams (PCTs) have been found to be effective at addressing the shortcomings in HPC. In this study, we attempted to outline unmet palliative care needs of terminal cancer patients and the potential benefits of PCTs as perceived by doctors in Korea. MATERIALS AND METHODS: We surveyed 474 doctors at 10 cancer-related academic conferences from June to November 2014 with a self-report questionnaire to assess their perceptions of end-of-life care needs and the expected effects of PCTs on caring for terminal cancer patients. Among those surveyed, 440 respondents who completed the entire questionnaire were analyzed. RESULTS: In all domains, fewer participants reported satisfaction with palliative care services than those reporting needs (p < 0.001). The surveyed participants also reported difficulties with a shortage of time for treatment, psychological burden, lack of knowledge regarding hospice care, lengths of stay, and palliative ward availability. Multivariate logistic regression analysis revealed that female doctors (odds ratio [OR], 2.672; 95% confidence interval [CI], 1.035 to 6.892), doctors who agreed that referring my patients to a HPC means I must give up on my patient (OR, 3.075; 95% CI, 1.324 to 7.127), and doctors who had no experience with HPC education (OR, 3.337; 95% CI, 1.600 to 7.125) were associated with higher expected effectiveness of PCT activities. CONCLUSION: The PCT activities were expected to fill the doctor's perceived unmet HPC needs of terminal cancer patients and difficulties in communications.