PURPOSE: This first Korean prospective study is to evaluate the feasibility of prone breast radiotherapy after breast conserving surgery for left breast cancer patients who have relatively small breast size and we present dosimetric comparison between prone and supine positions. MATERIALS AND METHODS: Fifty patients underwent two computed tomography (CT) simulations in supine and prone positions. Whole breast, ipsilateral lung, heart, and left-anterior-descending coronary artery were contoured on each simulation CT images. Tangential-fields treatment plan in each position was designed with total 50 Gy in 2-Gy fractions, and then one of the positions was designated for the treatment by comparing target coverage and dose to normal organs. Also, interfractional and intrafractional motion was evaluated using portal images. RESULTS: In total 50 patients, 32 cases were decided as prone-position–beneficial group and 18 cases as supine-position–beneficial group based on dosimetric advantage. Target dose homogeneity was comparable, but target conformity in prone position was closer to optimal than in supine position. For both group, prone position significantly increased lung volume. However, heart volumewas decreased by prone position for prone-position–beneficial group but was comparable between two positions for supine-position–beneficial group. Lung and heart doses were significantly decreased by prone position for prone-position–beneficial group. However, prone position for supine-position–beneficial group increased heart dose while decreasing lung dose. Prone position showed larger interfractional motion but smaller intra-fractional motion than supine position. CONCLUSION: Prone breast radiotherapy could be beneficial to a subset of small breast patients since it substantially spared normal organs while achieving adequate target coverage.
Breast Neoplasms ; Breast ; Coronary Vessels ; Feasibility Studies ; Heart ; Humans ; Lung ; Mastectomy, Segmental ; Prone Position ; Prospective Studies ; Radiotherapy ; Supine Position ; Unilateral Breast Neoplasms

Acrodermatitis continua of Hallopeau (ACH) is a rare form of acropustular eruption characterized by a presence of aseptic pustules on inflammatory periungual or subungual regions. Frequently accompanied by paronychia, atrophic skin changes, onychodystrophy, and osteolysis of distal phalanges of the digits, it is considered to be a variant of pustular psoriasis with a chronic relapsing course and refractoriness to many therapeutic modalities. Here, we present a case of a 45-year-old female who presented with multiple pustules pathologically diagnosed as pustular psoriasis on her left thumb. She suffered from ACH for over a decade, and in the process experienced frequent relapses and showed poor response to numerous treatment modalities such as narrow band UVB, topical steroid, steroid intralesional injection, oral retinoids, 308 nm excimer laser, and oral immune suppressants. However, the patient showed dramatic clinical improvements to administration of etanercept (TNF-alpha antagonist, twice a week) for a period of one month. The cessation of etanercept led to recurrence of symptoms and marked deterioration of the skin lesion within a month again, but the re-initiation of treatment soon relieved the problem. After completion of a three months trial of etanercept, the cutaneous lesion subsided, and the patient is now successfully controlled with topical steroid maintenance therapy. Hereby, we report a patient with ACH successfully treated with etanercept.
Acrodermatitis ; Female ; Humans ; Immunoglobulin G ; Injections, Intralesional ; Lasers, Excimer ; Middle Aged ; Osteolysis ; Paronychia ; Psoriasis ; Receptors, Tumor Necrosis Factor ; Recurrence ; Retinoids ; Skin ; Thumb ; Etanercept

Purpose: To evaluate and compare the feasibilities of magnetic resonance (MR) image-based planning using synthetic computed tomography (sCT) versus CT (pCT)-based planning in helical tomotherapy for prostate cancer. Materials and Methods: A retrospective evaluation was performed in 16 patients with prostate cancer who had been treated with helical tomotherapy. MR images were acquired using a dedicated therapy sequence; sCT images were generated using magnetic resonance for calculating attenuation (MRCAT). The three-dimensional dose distribution according to sCT was recalculated using a previously optimized plan and was compared with the doses calculated using pCT. Results: The mean planning target volume doses calculated by sCT and pCT differed by 0.65% ± 1.11% (p = 0.03). Three-dimensional gamma analysis at a 2%/2 mm dose difference/distance to agreement yielded a pass rate of 0.976 (range, 0.658 to 0.986). Conclusion The dose distribution results obtained using tomotherapy from MR-only simulations were in good agreement with the dose distribution results from simulation CT, with mean dose differences of less than 1% for target volume and normal organs in patients with prostate cancer.

Background: Data on severe acute respiratory syndrome coronavirus-2 transmission from a pediatric index patient to others at the school setting are limited. Epidemiological data on pediatric coronavirus disease 2019 (COVID-19) cases after school opening are warranted. Methods: We analyzed data of the pediatric patients with COVID-19 collected from the press release of the Korea Centers for Disease Control and Prevention. Information on the school opening delay and re-opening policies were achieved from the press release of the Korean Ministry of Education. Results: The school openings were delayed three times in March 2020. Online classes started from April 9, and off-line (in-person) classes started from May 20 to June 8 at four steps in different grades of students. There was no sudden increase in pediatric cases after the school opening, and the proportion of pediatric cases among total confirmed cases in the nation around 7.0%. As of July 31, 44 children from 38 schools and kindergartens were diagnosed with COVID-19 after off-line classes started. More than 13,000 students and staffs were tested; only one additional student was found to be infected in the same classroom. The proportions of pediatric patients without information on infection sources were higher in older age groups than in younger age groups (17.4% vs. 52.4%, P = 0.014). In the younger age group, 78.3% of children were infected by family members, while only 23.8% of adolescents in the older age group were infected by family members (P < 0.001). Conclusion Korea had a successful transition from school closure to online and off-line school opening, which did not cause significant school-related outbreak among the pediatric population.

Studies on target motion in 4-dimensional radiotherapy are being world-widely conducted to enhance treatment record and protection of normal organs. Prediction of tumor motion might be very useful and/or essential for especially free-breathing system during radiation delivery such as respiratory gating system and tumor tracking system. Neural network is powerful to express a time series with nonlinearity because its prediction algorithm is not governed by statistic formula but finds a rule of data expression. This study intended to assess applicability of neural network method to predict tumor motion in 4-dimensional radiotherapy. Scaled Conjugate Gradient algorithm was employed as a learning algorithm. Considering reparation data for 10 patients, prediction by the neural network algorithms was compared with the measurement by the real-time position management (RPM) system. The results showed that the neural network algorithm has the excellent accuracy of maximum absolute error smaller than 3 mm, except for the cases in which the maximum amplitude of respiration is over the range of respiration used in the learning process of neural network. It indicates the insufficient learning of the neural network for extrapolation. The problem could be solved by acquiring a full range of respiration before learning procedure. Further works are programmed to verify a feasibility of practical application for 4-dimensional treatment system, including prediction performance according to various system latency and irregular patterns of respiration.
Humans ; Learning ; Respiration ; Track and Field

Studies on target motion in 4-dimensional radiotherapy are being world-widely conducted to enhance treatment record and protection of normal organs. Prediction of tumor motion might be very useful and/or essential for especially free-breathing system during radiation delivery such as respiratory gating system and tumor tracking system. Neural network is powerful to express a time series with nonlinearity because its prediction algorithm is not governed by statistic formula but finds a rule of data expression. This study intended to assess applicability of neural network method to predict tumor motion in 4-dimensional radiotherapy. Scaled Conjugate Gradient algorithm was employed as a learning algorithm. Considering reparation data for 10 patients, prediction by the neural network algorithms was compared with the measurement by the real-time position management (RPM) system. The results showed that the neural network algorithm has the excellent accuracy of maximum absolute error smaller than 3 mm, except for the cases in which the maximum amplitude of respiration is over the range of respiration used in the learning process of neural network. It indicates the insufficient learning of the neural network for extrapolation. The problem could be solved by acquiring a full range of respiration before learning procedure. Further works are programmed to verify a feasibility of practical application for 4-dimensional treatment system, including prediction performance according to various system latency and irregular patterns of respiration.
Humans ; Learning ; Respiration ; Track and Field

Background: For the 2018–2019 season, the national influenza immunization program expanded to cover children aged from 6 months to 12 years in Korea. This study aimed to analyze vaccine effectiveness (VE) against influenza in children visiting the pediatric emergency room at a tertiary hospital during the 2018-2019 season. Methods: Patients tested for influenza antigens from October 1st 2018 to May 31st 2019 at the pediatric emergency room of Samsung Medical Center were included. Patients' influenza antigen test results, influenza vaccination history, and underlying medical conditions were reviewed retrospectively. VE was estimated from the test-negative design study. Results: Among the 2,901 visits with influenza test results 1,692 visits of 1,417 patients were included for analysis. Among these 1,417 patients, 285 (20.1%) were positive (influenza A, n = 211, 74.0%; influenza B, n = 74, 26.0%). The VE in all patients was 36.4% (95% confidence interval [CI], 13.9 to 53.1). The VE for influenza A was 37.6% (95% CI, 12.6 to 55.5) and VE for influenza B was 24.0% (−38.5 to 58.3). The VE in the age group 6 months to 12 years was significant with a value of 35.6% (95% CI, 10.5 to 53.7); it was not statistically significant in the age group 13 to 18 years. In a multivariate logistic regression model, patients who received an influenza vaccination were less likely to get influenza infection (OR, 0.6; 95% CI, 0.4 to 0.8; P = 0.001), with significant confounding factors such as age group 13 to 18 years (OR, 0.5; 95% CI, 0.3 to 0.8; P = 0.003) and underlying hematology-oncology disease (OR, 0.3;95% CI, 0.1 to 0.6; P = 0.002). Conclusion We report moderate effectiveness of influenza vaccination in previously healthy children aged from 6 months to 12 years in the 2018-2019 season.

Background: For the 2018–2019 season, the national influenza immunization program expanded to cover children aged from 6 months to 12 years in Korea. This study aimed to analyze vaccine effectiveness (VE) against influenza in children visiting the pediatric emergency room at a tertiary hospital during the 2018-2019 season. Methods: Patients tested for influenza antigens from October 1st 2018 to May 31st 2019 at the pediatric emergency room of Samsung Medical Center were included. Patients' influenza antigen test results, influenza vaccination history, and underlying medical conditions were reviewed retrospectively. VE was estimated from the test-negative design study. Results: Among the 2,901 visits with influenza test results 1,692 visits of 1,417 patients were included for analysis. Among these 1,417 patients, 285 (20.1%) were positive (influenza A, n = 211, 74.0%; influenza B, n = 74, 26.0%). The VE in all patients was 36.4% (95% confidence interval [CI], 13.9 to 53.1). The VE for influenza A was 37.6% (95% CI, 12.6 to 55.5) and VE for influenza B was 24.0% (−38.5 to 58.3). The VE in the age group 6 months to 12 years was significant with a value of 35.6% (95% CI, 10.5 to 53.7); it was not statistically significant in the age group 13 to 18 years. In a multivariate logistic regression model, patients who received an influenza vaccination were less likely to get influenza infection (OR, 0.6; 95% CI, 0.4 to 0.8; P = 0.001), with significant confounding factors such as age group 13 to 18 years (OR, 0.5; 95% CI, 0.3 to 0.8; P = 0.003) and underlying hematology-oncology disease (OR, 0.3;95% CI, 0.1 to 0.6; P = 0.002). Conclusion We report moderate effectiveness of influenza vaccination in previously healthy children aged from 6 months to 12 years in the 2018-2019 season.

Background: In pediatric patients, the common cold coronavirus (ccCoV) usually causes mild respiratory illness. There are reports of coronavirus causing central nervous system (CNS) infection in experimental animal models. Some immunocompromised patients have also been reported to have fatal CNS infections with ccCoV. The aim of this study was to investigate the clinical characteristics of CNS complications related to ccCoV infection. Methods: From January 2014 to December 2019, a retrospective analysis was performed of medical records from hospitalized patients under 19 years of age whose ccCoV was detected through polymerase chain reaction in respiratory specimens. The CNS complications were defined as clinically diagnosed seizure, meningitis, encephalopathy, and encephalitis. Results: A total of 436 samples from 420 patients were detected as ccCoV. Among the 420 patients, 269 patients were immunocompetent and 151 patients were immunocompromised.The most common type of ccCoV was OC43 (52% in immunocompetent, 37% in immunocompromised). CNS complications were observed in 9.4% (41/436). The most common type of CNS complication was the fever-provoked seizure under pre-existing neurologic disease (42% in immunocompetent and 60% in immunocompromised patients).Among patients with CNS complications, two immunocompetent patients required intensive care unit admission due to encephalitis. Three patients without underlying neurological disease started anti-seizure medications for the first time at this admission. There was no death related to ccCoV infection. Conclusion ccCoV infection may cause severe clinical manifestations such as CNS complications or neurologic sequelae, even in previously healthy children.

PURPOSE: The Korean Society of Radiation Oncologists (KOSRO) conducted the Patterns of Care Study (PCS) of radiotherapy (RT) for spine metastases in 2009. The current study was conducted to investigate current practice patterns and compare them with the results of the PCS. MATERIALS AND METHODS: The survey questionnaire was composed of 10 questions regarding general information and seven questions for each of two clinical scenarios. RESULTS: Fifty-four members of the KOSRO answered at least one question on the web-based questionnaire. The yearly number of patients treated who underwent palliative spine RT was greater than 200 in 14 (25.9%), 51 to 100 in 13 (24.1%), and 31 to 50 in 11 respondents (20.4%). Scenario 1 described a patient presenting with cord compressive spine metastasis in multiple bones and liver metastasis from non-small cell lung cancer. Thirty gray (Gy) in 10 fractions was chosen by 35 respondents (64.8%). Scenario 2 described a case of a single spine metastasis without progression after targeted therapy. Thirty Gy in 10 fractions was chosen by 19 respondents (35.2%), and a single fraction or less than four fractions of stereotactic ablative radiotherapy (SABR) were selected by 18 respondents (33.3%). When compared with the 2009 PCS, practice patterns of Korean radiation oncologists had not changed significantly over 5 years, except that SABR emerged as a new treatment modality in the selected population. CONCLUSION: The 2014 PCS demonstrated that multiple fraction RT is still preferred in a considerable proportion of Korean radiation oncologists.
Carcinoma, Non-Small-Cell Lung ; Data Collection ; Humans ; Korea ; Liver ; Neoplasm Metastasis* ; Practice Patterns, Physicians' ; Radiotherapy ; Spine* ; Surveys and Questionnaires