• Journal of Radiation Protection and Research
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• v.46 no.3
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• pp.83-97
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• 2021

Background: The lifetime risk of lung cancer incidence due to radiation for nonsmokers is overestimated because of the use of the average cancer baseline risk among a mixed population, including smokers. In recent years, the generalized multiplicative (GM)-excess relative risk (ERR) model has been developed in the life span study of atomic bomb survivors to consider the joint effect of radiation and smoking. Based on this background, this paper discusses the issues of radiation risk assessment considering smoking in two parts. Materials and Methods: In Part 1, we proposed a simple method of estimating the baseline risk for nonsmokers using current smoking data. We performed sensitivity analysis on baseline risk estimation to discuss the birth cohort effects. In Part 2, we applied the GM-ERR model for Japanese smokers to calculate lifetime attributable risk (LAR). We also performed a sensitivity analysis using other ERR models (e.g., simple additive (SA)-ERR model). Results and Discussion: In Part 1, the lifetime baseline risk from mixed population including smokers to nonsmokers decreased by 54% (44%-60%) for males and 24% (18%-29%) for females. In Part 2, comparison of LAR between SA- and GM-ERR models showed that if the radiation dose was ≤200 mGy or less, the difference between these ERR models was within the standard deviation of LAR due to the uncertainty of smoking information. Conclusion: The use of mixed population for baseline risk assessment overestimates the risk for lung cancer due to low-dose radiation exposure in Japanese males.

• Journal of Radiation Protection and Research
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• v.17 no.1
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• pp.57-70
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• 1992

An excess risk of lung cancer mortality among Koreans, attributable to indoor $^{222}Rn$ daughters exposure, were quantitatively evaluated by applying a stochastic health risk projection model on the radiation exposure. The lung cancer rate in Korean males and females, based on the 1989 demographic data, were estimated to be $22.4/10^5-y\;and\;9.5/10^5-y$, respectively The lifetime baseline lung cancer risks, deduced from these rates, appeared to be 0.047 and 0.019 for males and females, respectively, and were lower than the corresponding 1984 values of 0.067 and 0.025 in the U.S.A. The excess risk coefficients, derived by modified relative risk projection model of the BEIR-IV Committee under the US National Academy of Science, per annual 1.0 WLM of exposure to indoor radon daughters were estimated to be 0.022/WLM for males, 0.009/WLM for females, and 0.017/WLM for both sexes. The resulting annual frequency of excess lung cancer mortality for the life expectancy in the Korean population appeared to be 230/10^6-WLM, which was an approximate median of $120{\sim}450/10^6-WLM$ reported so far in the world.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4831-4836
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• 2016

The study aimed to find out to what degree suicidal thoughts and associated factors affect the suicide risk of advanced cancer patients. The frequency of suicidal thoughts among patients with cancer, especially in the advanced stages, is about 3 times greater than the adult average in South Korea. We recruited 457 participants with four types of cancers (colon, breast, cervical, and lung) using stratified sampling. Data collection was carried out through one-on-one interviews by trained nurses using a structured questionnaire. Advanced cancer patients with high, vs. low, levels of anxiety and pain had a higher suicide risk. In contrast, having one's spouse as the primary care provider was associated with a low suicide risk. Overall, the three factors of anxiety, pain, and the primary caregiver being one's spouse explained 17.2% of the variance in suicide risk. In conclusion, we derived influencing factors of suicide risk using a sample of patients with various types of advanced cancer. The results provide systematic baseline data for preparing nurse-led interventions to prevent suicidal thoughts and suicide attempts among advanced cancer patients.

• Journal of Preventive Medicine and Public Health
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• v.35 no.2
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• pp.123-128
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• 2002

Objective : To examine the relationship between cigarette smoking, alcohol and cancer mortality in men in the Kangwha cohort after 12 years and 10 months of follow up. Methods : The subjects consisted of 2,681 men in the Kangwha cohort aged over 55 in 1985. Number of deaths and the time to death front all cancers and other cause were measured and the data for the smoking and drinking habits were obtained from the baseline survey data in 1985. All subjects were categorized into four groups according to their smoking habits: non-smokers, ex-smokers, mode(ate-smokers (1-19 cigarettes per day), heavy-smokers ($\geq$20 cigarettes per day). In addition, they were also categorized according to their drinking habits: non-drinkers, light-drinkers ($\leq$1 drink per week), moderate-drinkers (<3 drinks per day), heavy-drinkers ($\geq$3 drinks per day). The cancer specific death rates were calculated according to their smoking and drinking status. The adjusted risk ratio for all cancer deaths according to their smoking and drinking status were estimated using the Cox's proportional hazard regression model. Results : Using nonsmokers as the reference category, the adjusted risk ratio for all cancer deaths were 1.573(95% CI=1.003-2.468) for heavy-smokers. For lung cancer deaths, the adjusted risk ratios were 3.540(95% CI=1.251-10.018) for moderate-smoker and 4.114(95% CI=1.275-13.271) for heavy-smokers. Compared to non-drinkers, the adjusted risk ratio for stomach cancer was 2.204(95% CI=1.114-4.361) for light-drinkers. Conclusion : Smoking is the most significant risk factor for cancer deaths particularly lung cancer.

• IEMEK Journal of Embedded Systems and Applications
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• v.17 no.5
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• pp.265-272
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• 2022

As the risk of lung cancer has increased, early-stage detection and treatment of cancers have received a lot of attention. Among various medical imaging approaches, computer tomography (CT) has been widely utilized to examine the size and growth rate of lung nodules. However, the process of manual examination is a time-consuming task, and it causes physical and mental fatigue for medical professionals. Recently, many computer-aided diagnostic methods have been proposed to reduce the workload of medical professionals. In recent studies, encoder-decoder architectures have shown reliable performances in medical image segmentation, and it is adopted to predict lesion candidates. However, localizing nodules in lung CT images is a challenging problem due to the extremely small sizes and unstructured shapes of nodules. To solve these problems, we utilize atrous spatial pyramid pooling (ASPP) to minimize the loss of information for a general U-Net baseline model to extract rich representations from various receptive fields. Moreover, we propose mixed-up attention mechanism of reverse, boundary and convolutional block attention module (CBAM) to improve the accuracy of segmentation small scale of various shapes. The performance of the proposed model is compared with several previous attention mechanisms on the LIDC-IDRI dataset, and experimental results demonstrate that reverse, boundary, and CBAM (RB-CBAM) are effective in the segmentation of small nodules.

• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.151-158
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• 2010

Objectives: The aim of this study was to evaluate the association between cigarette smoking and total mortality, cancer mortality and other disease mortalities in Korean adults. Methods: A total of 14 161 subjects of the Korean Multi-center Cancer Cohort who were over 40 years of age and who were cancer-free at baseline enrollment reported their lifestyle factors, including the smoking status. The median follow-up time was 6.6 years. During the follow-up period from 1993 to 2005, we identified 1159 cases of mortality, including 260 cancer mortality cases with a total of 91 987 person-years, by the national death certificate. Cox proportional hazard regression model was used to estimate the hazard ratio (HR) of cigarette smoking for total mortality, cancer mortality and disease-specific mortality, as adjusted for age, gender, the geographic area and year of enrollment, the alcohol consumption status, the education level and the body mass index (BMI). Results: Cigarette smoking was significantly associated with an increased risk of total mortality, all-cancer mortality and lung cancer mortality (p-trend, < 0.01, <0.01, <0.01, respectively). Compared to non-smoking, current smokers were at a higher risk for mortality [HR (95% CI)=1.3 (1.1 - 1.5) for total mortality; HR (95% CI)=1.6 (1.1 -2.2) for all-cancer mortality; HR (95% CI)=3.9 (1.9-7.7) for lung cancer mortality]. Conclusions: This study's results suggest that cigarette smoking might be associated with total mortality, all-cancer mortality and especially lung cancer mortality among Korean adults.