The aim of this study was to examine the association between indoor tanning use and the risk of overall and early-onset (age < 50) melanoma and non-melanoma skin cancer (NMSC). To evaluate the association between indoor tanning and skin cancer, a systematic review of the literature published until July 2021 was performed using PubMed, EMBASE, and MEDLINE. Summary relative risk (RR) from 18 studies with 10,406 NMSC cases and 36 studies with 14,583 melanoma cases showed significant association between skin cancer and indoor tanning (melanoma, RR= 1.27, 95% CI 1.16–1.39; NMSC, RR = 1.40, 95% CI 1.18–1.65; squamous cell carcinoma (SCC), RR = 1.58, 95% CI 1.38–1.81; basal cell carcinoma (BCC), RR = 1.24, 95% CI 1.00–1.55). The risk was more pronounced in early-onset skin cancer (melanoma, RR = 1.75, 95% CI 1.14–2.69; NMSC, RR = 1.99, 95% CI 1.48–2.68; SCC, RR = 1.81, 95% CI 1.38–2.37; BCC, RR = 1.75, 95% CI 1.15–2.77). Moreover, first exposure at an early age (age ≤ 20 years) and higher exposure (annual frequency ≥ 10 times) to indoor tanning showed increasing risk for melanoma (RR = 1.47, 95% CI 1.16–1.85; RR = 1.52, 1.22–1.89) and NMSC (RR = 2.02, 95% CI 1.44–2.83; RR = 1.56, 95% CI 1.31–1.86). These findings provide evidence supporting primary prevention policies regulating modifiable behaviors to reduce the additional risk of skin cancer among younger adults.

Model 1: Function(Y)=β₀+β₁ (UIC)

Background: Active surveillance (AS) has been established as an alternative to immediate surgery for low-risk papillary thyroid microcarcinoma (PTMC). Nonetheless, it remains difficult to decide between AS and immediate surgery, since limited objective evidence exists regarding risks and benefits. The aim of study is to compare the cumulative costs of AS and immediate surgery. Methods: To estimate cumulative costs, a hypothetical model is simulated based on the MAeSTro study, a multicenter prospective cohort study of AS for PTMC. Direct and indirect costs are estimated from diagnosis to the treatment decision and follow-up for 10 years and a longer period. In the case of the scenarios, AS, AS to surgery due to the changing their mind, and lobectomy (analyzed regardless of levothyroxine [LT4] treatment, as well as subdivided into lobectomy/LT4[-] and lobectomy/LT4[+]) is considered. A sensitivity analysis is performed using different discount rates to address uncertainties in future time costs. To compare the cumulative costs, we referred to previous research conducted in Hong Kong, the United States, and Japan. Results: The initial cost of AS is estimated to be 5.6 times lower than that of lobectomy (regardless of LT4 use), while the 10-year cumulative costs of AS ($2,545) and lobectomy regardless of LT4 ($3,045) are similar under a discount rate of 3%. However, in the long-term follow-up period, immediate surgery is going to be estimated more economical than AS. The costs of the two management approaches are similar in Hong Kong, but substantially different in the United States and Japan, implying that it could be affected by each country’s national health insurance coverage and the thyroid ultrasound interval during follow-up. Conclusion: Considering both direct and indirect costs, the cumulative costs of AS and immediate surgery in low-risk PTMC patients are similar during 10 years, and surgery could be more economical for patients with a life expectancy in long-term follow-up. However, careful interpretation is needed for long-term follow-up and the country’s health care system and environment. Nevertheless, considering the representative protocols and objective costs in South Korea, it is expected to be a key to suggest the appropriate treatment for PTMC patients.

Objectives: This study aimed to compare the Delta, Greenland, and Monte Carlo methods for estimating 95% confidence intervals (CIs) of the population-attributable fraction (PAF). The objectives were to identify the optimal method and to determine the influence of primary parameters on PAF calculations.Methods: A dataset was simulated using hypothetical values for primary parameters (population, relative risk [RR], prevalence, and variance of the beta estimator ) involved in PAF calculations. Three methods (Delta, Greenland, and Monte Carlo) were used to estimate the 95% CIs of the PAFs. Perturbation analysis was performed to assess the sensitivity of the PAF to changes in these parameters. An R Shiny application, the “GDM-PAF CI Explorer,” was developed to facilitate the analysis and visualization of these computations.Results: No significant differences were observed among the 3 methods when both the RR and p-value were low. The Delta method performed well under conditions of low prevalence or minimal RR, while Greenland’s method was effective in scenarios with high prevalence. Meanwhile, the Monte Carlo method calculated 95% CIs of PAFs that were stable overall, though it required intensive computational resources. In a novel approach that utilized perturbation for sensitivity analysis, was identified as the most influential parameter in the estimation of CIs.Conclusions: This study emphasizes the necessity of a careful approach for comparing 95% CI estimation methods for PAFs and selecting the method that best suits the context. It provides practical guidelines to researchers to increase the reliability and accuracy of epidemiological studies.

The increasing detection of papillary thyroid microcarcinoma (PTMC) has raised concerns regarding overtreatment. For low-risk PTMC, either immediate surgery or active surveillance (AS) can be considered. To facilitate the implementation of AS, the Korean Thyroid Association convened a multidisciplinary panel and developed the first Korean guideline. AS is recommended for adults with pathologically confirmed Bethesda V–VI PTMC who have no clinical evidence of lymph node or distant metastasis, gross extrathyroidal extension, invasion of the trachea or recurrent laryngeal nerve, or aggressive histology. A baseline assessment requires high-resolution neck ultrasound performed by experienced operators to exclude extrathyroidal extension, tracheal or recurrent laryngeal nerve invasion, and lymph node metastasis; contrast-enhanced neck computed tomography is optional. Patient characteristics, including age, comorbidities, and the capacity for long-term follow-up, should be thoroughly assessed. Shared decision-making should carefully weigh the benefits and risks of surgery versus AS, considering expected oncologic outcomes, potential complications, quality of life, anxiety, medical costs, and patient preference. Follow-up involves neck ultrasound and thyroid function tests every 6 months for 2 years and annually thereafter. Disease progression, defined as significant tumor growth or newly detected nodal or distant metastasis, warrants surgery. Despite remaining uncertainties, this guideline provides a structured framework to ensure oncologic safety and supports patient-centered AS.

Objectives: This study aimed to identify the current patterns of cancer incidence and estimate the projected cancer incidence and mortality between 2020 and 2035 in Korea.Methods: Data on cancer incidence cases were extracted from the Korean Statistical Information Service from 2000 to 2017, and data on cancer-related deaths were extracted from the National Cancer Center from 2000 to 2018. Cancer cases and deaths were classified according to the International Classification of Diseases, 10th edition. For the current patterns of cancer incidence, age-standardized incidence rates (ASIRs) and age-standardized mortality rates were investigated using the 2000 mid-year estimated population aged over 20 years and older. A joinpoint regression model was used to determine the 2020 to 2035 trends in cancer.Results: Overall, cancer cases were predicted to increase from 265 299 in 2020 to 474 085 in 2035 (growth rate: 1.8%). The greatest increase in the ASIR was projected for prostate cancer among male (7.84 vs. 189.53 per 100 000 people) and breast cancer among female (34.17 vs. 238.45 per 100 000 people) from 2000 to 2035. Overall cancer deaths were projected to increase from 81 717 in 2020 to 95 845 in 2035 (average annual growth rate: 1.2%). Although most cancer mortality rates were projected to decrease, those of breast, pancreatic, and ovarian cancer among female were projected to increase until 2035.Conclusions: These up-to-date projections of cancer incidence and mortality in the Korean population may be a significant resource for implementing cancer-related regulations or developing cancer treatments.