In the previous review, the physical aspect of heavy particles, with a focus on the carbon beam was introduced. Particle beam therapy has many potential advantages for cancer treatment without increasing severe side effects in normal tissue, these kinds of radiation have different biologic characteristics and have advantages over using conventional photon beam radiation during treatment. The relative biological effectiveness (RBE) is used for many biological, clinical endpoints among different radiation types and is the only convenient way to transfer the clinical experience in radiotherapy with photons to another type of radiation therapy. However, the RBE varies dependent on the energy of the beam, the fractionation, cell types, oxygenation status, and the biological endpoint studied. Thus this review describes the concerns about RBE related to particle beam to increase interests of the Korean radiation oncologists' society.
Carbon ; Cell Fractionation ; Oxygen ; Photons ; Population Characteristics ; Protons ; Relative Biological Effectiveness

PURPOSE: Compared to conventional radiotherapy (RT), intensity-modulated radiotherapy (IMRT) significantly reduces the rate of treatment-induced late toxicities in head and neck cancer. However, a clear survival benefit of IMRT over conventional RT has not yet been shown. This study is among the first comparative study to compare the survival rates between conventional RT and helical tomotherapy in head and neck cancer. MATERIALS AND METHODS: From January 2008 to November 2011, 37 patients received conventional RT and 30 patients received helical tomotherapy for management of head and neck cancer. We retrospectively compared the survival rates between patients treated with conventional RT and helical tomotherapy, and analyzed the prognostic factors for survival. RESULTS: The 1- and 2-year locoregional recurrence-free survival rates were 61.2% and 58.1% for the conventional RT group, 89.3% and 80.3% for the helical tomotherapy group, respectively. The locoregional recurrence-free survival rates of the helical tomotherapy group were significantly higher than conventional RT group (p = 0.029). There were no significant differences in the overall and distant metastasis-free survival between the two groups. RT technique, tumor stage, and RT duration were significant prognostic factors for locoregional recurrence-free survival. CONCLUSION: This study showed the locoregional recurrence-free survival benefits of helical tomotherapy in the treatment of head and neck cancers.
Head ; Head and Neck Neoplasms ; Humans ; Neck ; Radiotherapy, Intensity-Modulated ; Retrospective Studies ; Survival Rate

PURPOSE: The purpose of this study was to explore the experiences of clinical nurses over 40 years of age who were shift workers. METHODS: Data were collected from in-depth interviews with 10 clinical nurses over 40 years of age who had at least 10 years of clinical experience and who worked in 5 acute care hospitals. The data were analyzed using Braun & Clark's thematic analysis. RESULTS: One main theme, 3 themes, and 9 subthemes were derived. The main theme was "Sustaining a position still in conflict", and themes were as follows; "Being trained as a professional nurse", "Having unfavorable working conditions and damaged self-esteem", "Trying hard to get a sense of value as an experienced nurse" CONCLUSION: The results of this study show the issues of age and generational diversities in nurses in acute care hospitals. It is necessary to explore various ways to utilize the experience of older clinical nurses for the integrity of nursing organization and the development of the nursing profession.
Nursing ; Qualitative Research

Background: The government should find ways to improve the effectiveness of the policies to control the incidence and mortality of the infectious disease. The purpose of this study is to find out whether the trust in the government’s ability to respond to coronavirus disease 2019 (COVID-19) affects the quarantine and hospitalization rate, incidence and mortality rates of COVID-19 and quarantine rules compliance in each region of Korea. Methods: The subject of this study is 250 regions (si · gun · gu) in Korea, and the 2020 Community Health Survey data from the Korea Disease Control and Prevention Agency (KDCA) was used for the trust in the government’s ability to respond to COVID-19, quarantine and hospitalization rate and quarantine rules compliance. For the incidence and mortality of COVID-19 and community factors, data was obtained from KDCA and Korean Statistical Information Service. Path analysis was used to find out the degree of inter-variable influence, and community factors (socio-demographic factors, community health factors, and health behavior factors) were used as control variables. Results: The regional disparity in key variables showed that the late pandemic period cumulative incidence and mortality of COVID-19 were large, while the early pandemic period quarantine and hospitalization rate and quarantine rules compliance were small. Path analysis showed that when community factors were controlled, the trust in government was statistically significant in all of the late pandemic period cumulative incidence (p=0.024) and mortality (p=0.017), and quarantine rules compliance (p=0.011). Conclusion This study revealed that the higher the trust in the government’s ability to respond to COVID-19, the lower the COVID-19 mortality and the higher the quarantine rules compliance at the regional level in Korea. This suggests that when the government implements healthcare policies to control infectious diseases, it is necessary to consider trust to improve policy compliance and control the mortality of the disease and maintain high trust through several effective methods.

OBJECTIVES: Little is yet known about the determinants of bone mineral density (BMD) in young adults. Thus, in this study, we aimed to determine the factors that have an impact on BMD in young men. METHODS: Questionnaires were sent out to 111 male medical students. Information on age, socio-economic status, medical history, lifestyle, physical activity during adolescence, school club participation, current physical activity, and dietary intake were collected by the survey. Height, weight, percent body fat and muscle mass were estimated by bioelectrical impedance, and BMD was obtained using calcaneal quantitative ultrasound. Using the Poisson regression model, prevalence ratios (PRs) were used to estimate the degree of association between risk factors and osteopenia. RESULTS: The height and current physical activity showed a correlation to the Osteoporosis Index. Among the categorized variables, past physical activity during adolescence (p=0.002) showed a positive effect on the bone mineral content. In the multivariate model, past physical activity (> or =1 time/wk) had a protective effect on osteopenia (PR, 0.37; 95% confidence interval [CI], 0.18 to 0.75) and present physical activity (1000 metabolic equivalent of task-min/wk) decreased the risk of osteopenia (PR, 0.64; 95% CI, 0.44 to 0.91). CONCLUSIONS: Past physical activity during adolescence is as important as physical activity in the present for BMD in young men.
Adult ; Body Mass Index ; *Bone Density ; Calcium, Dietary ; Humans ; Male ; *Motor Activity ; Questionnaires ; Risk Factors ; Smoking ; Socioeconomic Factors ; Students, Medical/psychology ; Young Adult

PURPOSE: To evaluate the structural characteristics of a scientific network of radiation oncology society. MATERIALS AND METHODS: A total of 1,512 articles published from 1986 to April 2010 with the terms 'radiation oncology' or 'therapeutic radiology' were obtained in the KoreaMed database. The co-authors were analyzed according to their affiliation, and their relationship was used to build a matrix. With the matrix, centralization indices and the Key Player index were analyzed. We used UCINET 6.0 for the network analysis, Netdraw for determining a sociogram and Key Player 1.44 for the key player analysis. RESULTS: The centralization of the radiation oncology field decreased from 8.29% for the period from 1986~1990 to 1.84% from 2006~2010. However, when the Korean Journal of Medical Physics was excluded, centralization increased from 2.32% for the period from 2001~2005 to 3.80% from 2006~2010. This suggested that the communication in the clinical research field of radiation oncology is decreasing. In a node centralization analysis, Seoul National University was found to be the highest at 7.9%. Seoul National University showed the highest indices in the Outdegree (6.50%) and Indegree (8.54%), in addition to Betweenness (14.94%) and Eigenvector (135.234%). The Key Player analysis indicated that Inha University had the highest index at 0.491, but when the Korean Journal of Medical Physics was excluded, Yonsei University had the highest Key Player index at 0.584. CONCLUSION: The degree centrality in the network of radiation oncology decreased in the most recent period as more institutions are participating in network. However, the Betweenness centrality is still increasing, suggesting that the communications among research groups (clique) in radiation oncology is warranted.
Korea ; Radiation Oncology

OBJECTIVES: This study examined how trends in the weekly frequencies of gastrointestinal infectious diseases changed before and during the coronavirus disease 2019 (COVID-19) pandemic in Korea, and compared them with the trends in the United States. METHODS: We compared the weekly frequencies of gastrointestinal infectious diseases (16 bacterial and 6 viral diseases) in Korea during weeks 5-52 before and after COVID-19. In addition, the weekly frequencies of 5 gastrointestinal infectious diseases in the United States (data from the Centers for Disease Control and Prevention) that overlapped with those in Korea were compared. RESULTS: The mean weekly number of total cases of gastrointestinal infectious diseases in Korea showed a significant decrease (from 522 before COVID-19 to 245 after COVID-19, p<0.01). Only bacterial gastrointestinal infectious diseases caused by Campylobacter increased significantly; other bacterial gastrointestinal infectious diseases showed either a decrease or no change. The incidence of all other viral diseases decreased. In the United States, the weekly numbers of Salmonella, Campylobacter, typhoid, shigellosis, and hepatitis A virus cases sharply decreased after the COVID-19 outbreak. The weekly case numbers of all viral diseases markedly decreased in both countries; however, bacterial gastrointestinal infectious diseases showed a different pattern. CONCLUSIONS The incidence of gastrointestinal infectious diseases decreased after the COVID-19 outbreak. In contrast, Campylobacter infections showed an increasing trend in Korea, but a decreasing trend in the United States. Further studies are needed to elucidate the different trends in bacterial and viral infectious diseases before and after non-pharmaceutical interventions and between different countries.

PURPOSE: This study was designed to investigate the long-term oncologic outcomes for locally advanced rectal cancer patients after treatment with preoperative concurrent chemoradiotherapy followed by total mesorectal excision, and to identify prognostic factors that affect survival and pathologic response. MATERIALS AND METHODS: From June 1996 to June 2009, 135 patients with locally advanced rectal cancer were treated with preoperative concurrent chemoradiotherapy followed by total mesorectal excision at Kyung Hee University Hospital. Patient data was retrospectively collected and analyzed in order to determine the treatment outcomes and identify prognostic factors for survival. RESULTS: The median follow-up time was 50 months (range, 4.5 to 157.8 months). After preoperative chemoradiotherapy, sphincter preservation surgery was accomplished in 67.4% of whole patients. A complete pathologic response was achieved in 16% of patients. The estimated 5- and 8-year overall survival, loco-regional recurrence-free survival, and distant metastasis-free survival rate for all patients was 82.7% and 75.7%, 76.8% and 71.9%, 67.9% and 63.3%, respectively. The estimated 5- and 8-year overall survival, loco-regional recurrence-free survival, and distant metastasis-free survival rate for pathologic complete responders was 100% and 100%, 100% and 88.9%, 95.5% and 95.5%, respectively. In the multivariate analysis, pathologic complete response was significantly associated with overall survival. The predictive factor for pathologic complete response was pretreatment clinical stage. CONCLUSION: Preoperative chemoradiotherapy for locally advanced rectal cancer resulted in a high rate of overall survival, sphincter preservation, down-staging, and pathologic complete response. The patients achieving pathologic complete response had very favorable outcomes. Pathologic complete response was a significant prognostic factor for overall survival and the significant predictive factor for a pathologic complete response was pretreatment clinical stage.
Chemoradiotherapy ; Follow-Up Studies ; Humans ; Multivariate Analysis ; Preoperative Care ; Rectal Neoplasms ; Retrospective Studies ; Survival Rate

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) patients with spinal metastasis (SM) show heterogeneous lengths of survival. In this study, we develop and propose a graded prognostic assessment for HCC patients with SM (HCC-SM GPA). METHODS: We previously reported the outcomes of 192 HCC patients with SM who received radiotherapy from April 1992 to February 2012. Prognostic factors that significantly affected survival in that study were used to establish the HCC-SM GPA. Validation was performed using an independent cohort of 63 patients recruited from September 2011 to March 2016. RESULTS: We developed the HCC-SM GPA using the following factors: Eastern Cooperative Oncology Group performance status (0–2, 0 point; 3–4, 1 point), controlled primary HCC (yes, 0 point; no, 2 points), and extrahepatic metastases other than bone (no, 0 point; yes, 1 point). Patients were stratified into low (GPA=0), intermediate (GPA=1 to 2), and high risk (GPA=3 to 4). When applied to the validation cohort, the HCC-SM GPA determined median survival durations of 13.6, 4.8, and 2.6 months and 1-year overall survival rates of 58.3%, 17.8%, and 7.3% for the low-, intermediate-, and high-risk patient groups, respectively (p<0.001). CONCLUSIONS: Our newly proposed HCC-SM GPA successfully predicted survival outcomes.
Carcinoma, Hepatocellular* ; Cohort Studies ; Humans ; Neoplasm Metastasis* ; Radiotherapy ; Survival Rate

PURPOSE: We investigated the role of radiotherapy (RT) for pancreatobiliary neuroendocrine tumors (PB-NETs). MATERIALS AND METHODS: We identified 9 patients with PB-NETs who received RT between January 2005 and March 2012. Of these 9 patients, 4 were diagnosed with NETs in the pancreas and 5 were diagnosed with NETs in the gallbladder. All patients received RT to the primary tumor or resection bed with a median total irradiation dose of 50.4 Gy, with or without chemotherapy. RESULTS: The tumor response rate and tumor control rate in the RT field were 60% and 100 %, respectively. All 4 patients who underwent surgery had no evidence of disease in the RT field. Of the 5 patients who received RT to the primary gross tumor, 1 had complete response, 2 had partial response, and 2 had stable disease in the RT field. The median time to progression was 11 months. Of the 9 patients, four patients had no progression, and 5 patients had progression of disease (locoregional, 2; distant, 2; locoregional/distant, 1). Of the 4 patients without progression, 3 were treated with RT in adjuvant or neoadjuvant setting, and one received RT to primary tumor. One patient experienced radiation-induced duodenitis at 3 months after concurrent chemoradiation without treatment-related mortality. CONCLUSION: RT can yield local control for advanced PB-NETs. RT should be considered an essential part of multimodality treatment in management of advanced PB-NETs.
Duodenitis ; Gallbladder ; Humans ; Neuroendocrine Tumors ; Pancreas ; Treatment Outcome