Changes of Nodular Size and Its Risk Factors in Iodine-Sufficient Area: a Retrospective Cohort Analysis of 7753 Thyroid Nodules

Background and Objectives@#Iodine is known to be an important factor in the occurrence of goiter, and South Korea is a region with sufficient iodine supplementation. In this regard, we checked the size change of thyroid nodules found by health check-up in Koreans and examined which risk factors influence the size change. @*Materials and Methods@#A total 7753 subjects who underwent thyroid sonography two or more times were included. We defined that there was a change in the size of the nodule when the difference in diameter identified in the last ultrasound was more than 3 mm. @*Results@#Thyroid nodules were decreased in 895 subjects (11.5%) and increased in 1041 subjects (13.5%). The rate of increased nodule was on an increasing trend according to the duration (annual percent change 2.6%, p＜0.001). In contrast, the rate of decreased nodule was unchanged. Predictive factors related to decrease of the nodule size were young age, male sex, larger initial nodule size and thyroiditis. Similarly, young age, larger initial nodule size and diffuse parenchymal abnormality were significant predictive factors for increased nodules. However, diffuse parenchymal abnormality was not a predictive factor when we analyzed only thyroid nodules larger than 1 cm. @*Conclusion@#In our study, 11.5-13.5% of benign thyroid nodules were increased or decreased during median 27 months of follow-up in iodine sufficient condition. Young age, larger initial size and diffuse parenchymal abnormality were common predictive factor affecting both the increase and decrease of thyroid nodules.

Prevalence of thyroid nodules and their associated clinical parameters: a large-scale, multicenter-based health checkup study

BACKGROUND/AIMS: We evaluated the prevalence and characteristics of thyroid nodules detected by thyroid ultrasound (US) at health checkups and the associated clinical parameters. METHODS: A total of 72,319 subjects who underwent thyroid US at three health checkup centers in Korea from January 2004 to December 2010 were included in this study. The correlations between the presence of thyroid nodules and other clinical parameters were analyzed. RESULTS: The prevalence of thyroid nodules and cysts was 34.2% (n = 24,757). Thyroid nodules were more prevalent in women and older age groups. Among the subjects with thyroid nodules with size information (n = 24,686), 18,833 (76.3%) had nodules measuring ≤ 1.0 cm. Women and older age groups showed higher proportion of larger nodules. Percentage of women, age, body mass index (BMI), waist circumference, body fat composition, blood pressure, and the level of fasting glucose, total cholesterol, and low density lipoprotein cholesterol were higher in the subjects with thyroid nodules compared to those without nodules. The prevalence of metabolic syndrome and overt/subclinical thyrotoxic state was higher in the subjects with thyroid nodules. In the multivariable logistic regression analysis, women, age, BMI, metabolic syndrome, and thyrotoxicosis were independently associated with the presence of thyroid nodules. CONCLUSIONS: The high prevalence of thyroid nodules in people who underwent thyroid US at a health checkup suggests that increased detection of thyroid nodules resulted in an increased prevalence in the general population. However, metabolic disturbances may also have contributed to the increase in thyroid nodule prevalence in Korea.

Results of Colorectal Cancer Screening of the National Cancer Screening Program in Korea, 2008 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study aims to investigate the current situation of national colorectal cancer screening by analyzing participation rates, positive rates of screening methods and screening rate of secondary screening tests in colorectal screening of the national cancer screening program in 2008. MATERIALS AND METHODS: With database about target population and screened individuals of the national cancer screening program, the results of target population and participants of colorectal cancer screening in 2008 were analyzed. Among adults aged over 50 years of medical aid and beneficiaries of national health insurance paying lower 50% premiums in the total subscribers, 4,640,365 were target population of colorectal cancer screening and the data of 984,915 undergoing fecal occult blood test (FOBT) as a primary screening were analyzed. RESULTS: The colorectal cancer screening rate was 21.2% and the rates of national health insurance subscribers, females and the elderly aged 60-64 years were higher than those of others. The recipients with a positive result in FOBT recorded approximately 7.5%. Medical aid beneficiaries (7.9%), males (8.8%) and seniors aged over 75 years (9.1%) showed higher positive rates than the average one. Out of the FOBT positive recipients, 43.0% took a secondary screening and the rate undergoing colonoscopy (31.4%) was higher than that of doing double-contrast barium enema test (11.6%). CONCLUSION: Colorectal cancer screening rate of medical aid beneficiaries and people paying lower 50% premiums among national health insurance subscribers, was different according to demographic characters (gender, age and types of health insurance). This finding meant that screening for the vulnerable needed to be encouraged by considering socio-demographic characters. Additionally, more efforts were necessary to increase the secondary screening rate of people with a positive result in primary one.

Trends of Mammography Use in a National Breast Cancer Screening Program, 2004-2008 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Korea started breast cancer screening as part of the National Cancer Screening Program (NCSP) in 1999. In order to identify under-served groups, we investigated mammography uptake in the National Breast Cancer Screening Program. MATERIALS AND METHODS: The study population was participants in the National Breast Cancer Screening Program from 2004 to 2008. We analyzed participation rates by insurance type, age group, and area of residence. RESULTS: Total participation rates for breast cancer screening increased from 18.2% in 2004 to 35.0% in 2008. The participation rate in the group aged 60 to 69 years showed the greatest increase, 21.3%, among the four age groups. Although the screening rate increased continuously, the participation rate of the Medical Aid Program (MAP) group was low compared to the National Health Insurance (NHI) group. Moreover, the increasing trend of mammography uptake in the MAP group was much lower than that of the NHI group. CONCLUSION: The participation rate for breast cancer screening in the NCSP in Korea has increased. However, the participation rate in mammography among MAP recipients is still lower than that of NHI beneficiaries. To increase mammography uptake, it is important to make it available to everyone by ensuring inclusion of all population subgroups.

Breast Cancer Screening in Korean Women: Report of the National Cancer Screening Program in 2008 / 한국유방암학회지

PURPOSE: The Korean National Cancer Screening Program began in 1999. To provide essential evidence related to breast cancer screening in Korean women, we analyzed data from the KNCSP in 2008. METHODS: Using data obtained from the National Cancer Screening Information System, breast cancer screening participation rates were calculated. Recall rates were estimated with 95% confidence intervals (CI). RESULTS: The target population of breast cancer screening in 2008 included 3,706,062 women, 1,294,060 of whom utilized mammography as a screening tool (participation rate, 34.9%). Compared to the participation rate of women covered by the National Health Insurance Program (37.3%), women covered by the Medical Aid Program was lower (21.3%). The overall recall rate of breast cancer screening was 6.4% (95% CI, 6.39-6.47). CONCLUSION: According to our study, efforts to facilitate the participation and to reduce disparities in breast cancer screening among Korean women are needed. These results will provide essential data for evidence-based strategies in breast cancer control in Korea.