• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.177-183
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• 2018

Purpose : Volumetric Modulated Arc Therapy(VMAT) has the advantage of uniformly and precisely irradiating the tumor to the shape of the tumor while reducing the risk of radiation damage to normal tissues. such as brain cancer, head and neck cancer and prostate cancer, It is being used for treatment. The purpose of this study is to evaluate the usefulness of the Jaw-Tracking technique(JTT) in VMAT for brain and head and neck cancer. Materials and Methods : We selected eight patients with brain and head and neck cancer(4 Brain, 4 head and neck) who were treated with the VMAT treatment technique. Contouring information of the patient's tumor and normal organ was fused to the Rando phantom using the deformable registration of Velocity(Varian, USA). A treatment plan was developed using the Varian Eclipse(ver 15.5, Varian, USA) with the same patient actual beam parameters except for the use of jaw-tracking. As the evaluation index, the maximum dose and mean dose of target and OAR were compared and a portal dosimetry was performed for the treatment plan verification. Results : When using JTT, the relative dose of OAR decreased by 5.24 % and the maximum dose by 7.05 %, respectively, compared with the Static-Jaw technique(SJT). In the various OARs, the mean dose and maximum dose reduction ranges ranged from 0.01 to 3.16 Gy and from 0.12 to 6.27 Gy, respectively. In the case of the target, the maximum dose of GTV, CTV, PTV decreased by 0.17 %, 0.43 %, and 0.37 % in JTT, and the mean dose decreased by 0.24 %, 0.47 % and 0.47 %, respectively. Gamma analysis The JTT and SJT passing rates were $98{\pm}1.73%$ and $97{\pm}1.83%$ on the basis of 3 % / 3 mm, respectively. Comparing the doses of all OARs applied to the experiment, it was found that the use of JTT resulted in a significant decrease in dose due to additional jaw shielding besides MLC than SJT. Conclusion : In radiation therapy using VMAT treatment plan, we can apply JTT in the case of adjacent tumor and normal organs such as brain cancer and head and neck cancer, and in radiotherapy required large field and high energy caused increase leakage dose through MLC. It is considered that the target dose of PTV can be increased by lowering the dose of normal tissue surrounding the tumor.

• Journal of radiological science and technology
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• v.40 no.1
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• pp.57-62
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• 2017

The purpose of this study is to reconstruct the treatment plan by applying CBCT and DIR to dose changes according to the change of the patient's motion and breast shape in the large breast cancer patients and to compare the doses using TWF, FIF and IMRT. CT and CBCT were performed with MIM6 to create DIRCT and each treatment plan was made. The patient underwent computed tomography simulation in both prone and supine position. The homogeneity index (HI), conformity index (CI), coverage index (CVI) to the left breast as planning target volume (PTV) were determined and the doses to the lung, heart, and right breast as organ at risk (OAR) were compared by using dose-volume histogram and the unique property of each organ. The value of HI of the PTV breast increased in all treatment planning methods using DIRCT, and CVI and CI were decreased in the treatment planning methods using DIRCT.

• Journal of Preventive Medicine and Public Health
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• v.41 no.4
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• pp.272-278
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• 2008

Objectives: To compare the health behaviors of widowed women with those of currently married women. Methods: We randomly sampled the subjects from the Jeollanamdo Resident Registration Data and we then selected 2,331 widowed women and 4,775 married women. Well-trained examiners measured the height, weight, blood pressure and abdomen circumference, and the women were interviewed with using a questionnaire. Logistic regression analysis was used to estimate the odds ratios(OR) of the two groups. Results: The smoking rate (OR=2.46; 95% confidence interval [CI]1.65, 3.66) was significantly higher for the widowed women. On the contrary, the awareness rate of a smoking cessation campaign (OR=0.80; 95% CI=0.70, 0.92), a quit tobacco telephone line (OR=0.73; 95% CI =0.61, 0.88) and a quit smoking clinic (OR=0.74; 95% CI=0.62, 0.89) were lower for the widowed women. The rate of receiving a health exam (OR=0.80; 95% CI=0.70, 0.91), the rate of undergoing gastric cancer screening (OR=0.77; 95% CI=0.68, 0.88), breast cancer screening (OR=0.79; 95% CI=0.69, 0.89), cervix cancer screening in the last 2 years (OR=0.81; 95% CI=0.71, 0.92), colon cancer screening in the last 5 years (OR=0.74; 95% CI=0.63, 0.87) were significantly lower for the widowed women. Conclusions: This study revealed that the health behaviors are significantly different between the widowed women and the married women. To improve the health behaviors of the widowed women, further study and research that will investigate the socioeconomic and environmental factors that affect the health behaviors of widowed women will be needed.

• Journal of Gastric Cancer
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• v.17 no.3
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• pp.255-266
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• 2017

Purpose: Although Roux-en-Y (R-Y) reconstruction after distal gastrectomy has several advantages, such as prevention of bile reflux into the remnant stomach, it is rarely used because of the technical difficulty. This prospective randomized clinical trial aimed to show the efficacy of a novel method of R-Y reconstruction involving the use of 2 circular staplers by comparing this novel method to Billroth-I (B-I) reconstruction. Materials and Methods: A total of 118 patients were randomly allocated into the R-Y (59 patients) and B-I reconstruction (59 patients) groups. R-Y anastomosis was performed using two circular staplers and no hand sewing. The primary end-point of this clinical trial was the reflux of bile into the remnant stomach evaluated using endoscopic and histological findings at 6 months after surgery. Results: No significant differences in clinicopathological findings were observed between the 2 groups. Although anastomosis time was significantly longer for the patients of the R-Y group (P<0.001), no difference was detected between the 2 groups in terms of the total surgery duration (P=0.112). Endoscopic findings showed a significant reduction of bile reflux in the remnant stomach in the R-Y group (P<0.001), and the histological findings showed that reflux gastritis was more significant in the B-I group than in the R-Y group (P=0.026). Conclusions: The results of this randomized controlled clinical trial showed that compared with B-I reconstruction, R-Y reconstruction using circular staplers is a safe and feasible procedure. This clinical trial study was registered at www.ClinicalTrials.gov (registration No. NCT01142271).

• Korean Journal of Health Education and Promotion
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• v.20 no.4
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• pp.51-65
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• 2003

Objectives： To examine the regional mortality differences in The Republic of Korea according to geographic location. Methods： All 232 administrative districts of the Republic of Korea in 1998 were studied according to their geographic locations by dividing each district into three categories； "metropolis," "urban," and "rural". Crude mortality rates for doth sexes from total deaths as well as the three major causes of death in Korea (cardiovascular disease, cancer, and external causes) were calculated with raw data from the "1998 report on the causes of death statistics" and resident registration data. Standardized mortality ratios (SMR) were calculated using the indirect standardization method. Poisson regression analyses were performed to examine the effects of geographic locations on the risk of death. To correct for the socioeconomic differences of each region, the percentage of old ($\geq$ 65 years old) population, the number of privately owned cars per 100 population, and per capita manufacturing production industries were included in the model. Results： Most SMRs were the lowest in the metropolis and the highest in the rural areas. These differences were more prominent in men and in deaths from external causes. In deaths from cancer in women, the rural region showed the lowest SMR. In Poisson regression analysis after correcting for regional socioeconomic differences, the risk of death from all causes significantly increased in both urban (OR＝1.111) and rural (OR＝1.100) regions, except for rural women, compared to the metropolis region. In men, the rural region showed higher risk (OR＝1.180) than the urban region (OR＝1.l51). For cardiovascular disease and cancer, significant differences were not found between geographic locations, except in urban women for cardiovascular disease (OR＝1.151) and in rural women for cancer (OR＝0.887), compared to metropolis women. In deaths from external causes, the risk ratios significantly increased in both urban and rural regions and an increasing tendency from the metropolis to the rural region was clearly observed in both sexes. Conclusions： Regional mortality differences according to geographic location exist in The Republic of Korea and further research and policy approaches to reduce these differences are needed. to reduce these differences are needed.

• Journal of Gastric Cancer
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• v.22 no.1
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• pp.35-46
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• 2022

Background: The correlation between hospital volume and postoperative outcomes has led to the centralization of complex procedures in several countries. However, the results reported in relation to gastric cancer (GC) are contradictory. This study aimed to analyze GC surgical volumes and 30-day postoperative mortality in Italy and to provide a simulation for modeling centralization of GC resections based on district case volumes. Methods: A national registry was used to identify all GC resections, record mortality rates, and track the national in-border GC resection health travel. Hospitals were grouped according to caseload. Centralization of all GC procedures performed within the same district was modeled. The outcome measures were a minimal volume of 25 GC resections/year and the 30-day postoperative mortality. Results: In 2018, 5,873 GC resections were performed in 498 Italian hospitals (mean resections per hospital per year: 11.8); the postoperative mortality rate (5.51%) was tracked from 2016-2018. GC resection health travel ranged from 2% to 50.5%, with a significant (P<0.001) difference between northern and central/southern Italy. The mean mortality rate was 7.7% in hospitals performing one to 3 GC resections per year, compared with 4.7% in those with >17 GC resections/year (P≤0.01). Most Italian districts achieved 25 procedures/year after centralization; however, 66.3% of GC cases in southern Italy vs. 42.2% in central and 52.7% in the northern regions (P<0.001) required reallocation. Conclusion: Postoperative mortality after GC resection correlated with hospital volume. Despite health travel, most Italian districts can reach a high-volume threshold, but discrepancies in mortality rates are alarming.Trial RegistrationResearch Registry Identifierresearchregistry6869

• Progress in Medical Physics
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• v.32 no.4
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• pp.172-178
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• 2021

Purpose: This study aimed to develop a deep learning architecture combining two task models to generate synthetic computed tomography (sCT) images from low-tesla magnetic resonance (MR) images to improve metallic marker visibility. Methods: Twenty-three patients with cervical cancer treated with intracavitary radiotherapy (ICR) were retrospectively enrolled, and images were acquired using both a computed tomography (CT) scanner and a low-tesla MR machine. The CT images were aligned to the corresponding MR images using a deformable registration, and the metallic dummy source markers were delineated using threshold-based segmentation followed by manual modification. The deformed CT (dCT), MR, and segmentation mask pairs were used for training and testing. The sCT generation model has a cascaded three-dimensional (3D) U-Net-based architecture that converts MR images to CT images and segments the metallic marker. The performance of the model was evaluated with intensity-based comparison metrics. Results: The proposed model with segmentation loss outperformed the 3D U-Net in terms of errors between the sCT and dCT. The structural similarity score difference was not significant. Conclusions: Our study shows the two-task-based deep learning models for generating the sCT images using low-tesla MR images for 3D ICR. This approach will be useful to the MR-only workflow in high-dose-rate brachytherapy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10505-10508
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• 2015

Background: Breast cancer is an important cause of death among women. One way of classifying different forms of breast cancer is by molecular features, usually in terms of the four subtypes: luminal A, luminal B, HER2-enriched, and triple negative. Objectives: This study aimed to investigate the association between molecular subtypes and survival among breast cancer patients treated with radiotherapy. Materials and Methods: A retrospective cohort study was conducted. The subjects were 272 breast cancer patients who had received treatment in the radiotherapy unit at Srinagarind Hospital, Thailand, between 1 January, 1999, and 31 May, 2009. The end of the study was 1 June, 2014. Overall survival was defined as the time elapsing between initial registration at the radiotherapy unit and death or the end of the study. Survival curves were estimated by the Kaplan-Meier method, and a multivariate analysis was performed using Cox's proportional hazard regression model. Results: The patient mean age was $47.5{\pm}10.4$ at the time of diagnosis. Of the 272 patients, 146 (53.7%) were classified as luminal A, 12 (4.4%) as luminal B, 30 (11.0%) as HER2-enriched, and 84 (30.9%) as triple negative. The overall survival rates at 1, 3 and 5 years were 87.1%, 68.4% and 59.2%, respectively. According to molecular subtypes, HER2-enriched patients had the lowest 5-year survival rate (30.0 %, 95%CI: 15.02-46.55). The median follow-up time was 8.37 years. In the Cox model analysis a higher risk of death was found for patients with HER2-enriched ($HR_{adj}=3.34$, 95%CI:1.96-5.67), triple negative ($HR_{adj}=2.17$, 95%CI: 1.44-3.27), and stage IIlB ($HR_{adj}=2.20$, 95%CI: 1.16-4.17) cancers. Conclusions: The worst survival rates were among patients classified as HER2-enriched, triple negative and at stage IIIB. Early detection and an advanced treatment modality are needed to help these patients.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2119-2125
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• 2013

Background: The aim of the study was to determine risk factors for cervical cancer for women in Izmir. Methods: This cross-sectional, descriptive field covered a population of 4319 women of reproductive age (15-49) (household registration in the Mukhtar's office-2007). A total of 1,637 women were included in the sample given a four-part questionnaire through face-to-face interview by visiting the women in their homes in order to determine socio-demographic factors, obstetric history, genital hygiene and the use of family planning methods. In addition, during the data collection process, the women were given group training in order to raise awareness of cervical cancer. The number and percentage distributions of the data were calculated. Results: While the average age of the women was $31.9{\pm}9.77$ (Min: 15.00-Max: 49.00), education level of 43.4% of them was elementary school only. It was determined that 70.3% of the women experienced at least one pregnancy, 71.0% had vaginal delivery and 75.9% used a contraceptive method. In the study it was determined that among the cervical cancer related risks vaginal delivery, vaginal lavage and having three or more pregnancies had the highest rates, while having sexual intercourse before 16 years of age and having more than one sexual partner constituted lower rates. The rate of the women who stated not having a smear in the last three years was 82.4%. Conclusions: Considering the case in terms of having Pap smear test, women's awareness on the risk factors and early diagnosis of cervical cancer was found to be low. Due to this reason, awareness of women has to be raised through education.

• Journal of Environmental Health Sciences
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• v.39 no.4
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• pp.335-345
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• 2013

Objectives: As the suspicion was raised that 'Agent Orange' was reclaimed 30 years ago at Camp Carol, located in Waegwan, Gyeongsangbuk-do, the government conducted an investigation of the influence of environmental and health effects around Camp Carol through a public-private joint investigation team. As part of the investigation of population health effects, this study was carried out in order to observe changes and regional differences in diseases, particularly cancer, by year. Methods: We authors conducted an analysis of secondary health data, such as cancer registration data, mortality data, and health insurance data. We drew an age standardized incidence ratio (SIR), death rate (SDR), mortality ratio (SMR), and health care utilization rate using these data. Results: For gastric cancer in women, and other cancers in men, a significant increase in incidence was observed compared to the control area. For biliary tract cancer, gallbladder cancer, and thyroid cancer in women, and prostate cancer in men, a significant decrease in incidence was observed compared to the control area. In the national statistical analysis of data, such as health insurance data and mortality data, we did not observe a significant increase at the Waegwan region compared to other regions. Conclusions: We must consider the limitations of this study. Because thirty years have passed from the time of the estimated landfill of 'Agent Orange', recent national statistical data may not reflect the past real situation. Therefore, the monitoring of secondary data for health effects at the municipal level should be carried out continuously.