• Radiation Oncology Journal
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• 제27권1호
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• pp.10-14
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• 2009

목적: 식도암에서 수술 후 방사선치료 및 방사선 단독 치료의 효과를 검증하고 예후 인자를 알아보고자 하였다. 대상 및 방법: 1989년부터 2006년까지 방사선치료를 받은 132명의 환자를 후향적으로 분석하였다. 35명은 제2병기 88명은 제3병기 9명은 제4병기 환자였다. 상부 식도암이 18명, 하부 식도암이 33명이었으며 중등부 식도암이 81명이었다. 60명에서는 방사선 단독 치료를 시행하였고 72명은 수술 후 방사선치료를 받았다. 8명에서는 40 Gy 이하를 조사하였으며 78명에서는 40내지 50 Gy를 조사하였다. 나머지 46명은 50내지 60 Gy를 조사 받았으며 수술 후 방사선치료를 받은 대부분의 환자는 45 Gy를 조사받았다. 결과: 전체 환자의 2년 및 5년 생존율은 24% 및 5%이었고 중앙 생존기간은 11개월이었다. 수술 후 방사선치료군의 2년 및 5년 생존율은 19% 및 8%, 방사선 단독치료군의 2년 및 5년 생존율은 18% 및 2%이었다. 제2병기, 제3 병기 및 제4병기 환자의 2년 및 5년 생존율은 각각 43% 및 15, 22% 및 2, 0% 및 0% 이었으며 이는 통계적으로 유의하였다. 상부, 중등부, 하부 식도암의 2년 생존율은 각각 19, 29, 22%이었으며 통계적으로 유의한 차이는 나타나지 않았다. 방사선 단독치료군에서 13명(22%)은 완전관해를, 40명(67%)은 부분관해를 보였고 7명(12%)은 반응을 보이지 않았다. 완전관해를 보인 환자군이 부분관해를 보인 환자군보다 더 나은 2년 생존율을 나타내었다(31% vs 17%). 결론: 식도암에서 방사선치료는 효과적이고 유용한 치료 방법이었으며 병기 및 방사선치료에의 반응 정도가 유의한 예후인자이었다. 그러나 식도암의 장기 생존율 및 예후가 만족스럽지 못하므로 더욱 효과적인 치료 방법의 개발이 향후 필요하리라 사료된다.

• 한국의학물리학회지:의학물리
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• 제28권4호
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• pp.218-225
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• 2017

Effects on skin caused by the dose from linear accelerator (LINAC) opposing portal irradiation and TomoDirect 3-D modeling treatment according to the radiation devices and treatment methods were measured, and a comparative analysis was performed. Two groups of 10 patients each were created and measurements were carried out using an optically stimulated luminescence dosimeter. These patients were already receiving radiation treatment in the hospital. Using the SPSS statistical program, the minimum and maximum average standard deviations of the measured skin dose data were obtained. Two types of treatment method were selected as independent variables; the measured points and total average were the dependent variables. An independent sample T-test was used, and it was checked whether there was a significance probability between the two groups. The average of the measured results for the LINAC opposing portal radiation was 117.7 cGy and PDD 65.39% for the inner breast, 144.7 cGy and PDD 80.39% for the outer breast, 143.2 cGy and PDD 79.56% for the upper breast, 151.4 cGy and PDD 84.11% for the lower breast, 149.6 cGy and PDD 83.11% for the axilla, and 141.32 cGy and PDD 78.51% for the total average. In contrast, for TomoDirect 3-D conformal radiotherapy, the corresponding measurement values were 137.6 cGy and PDD 76.44%, 152.3 cGy and PDD 84.61%, 148.6 cGy and PDD 82.56%, 159.7 cGy and PDD 88.72%, and 148.6 cGy PDD 82.56%, respectively, and the total average was 149.36 cGy and PDD 82.98%. To determine if the difference between the total averages was statistically significant, the independent sample T-test of the SPSS statistical program was used, which indicated that the P-value was P=0.024, which was 0.05 lower than the significance level. Thus, it can be understood that the null hypothesis can be dismissed, and that there was a difference in the averages. In conclusion, even though the treatment dose was similar, there could be a difference in the dose entering the body surface from the radiation treatment plan; however, depending on the properties of the treatment devices, there is a difference in the dose affecting the body surface. Thus, the absorbed dose entering the body surface can be high. During breast cancer radiotherapy, radiation dermatitis occurs in almost all patients. Most patients have a difficult time while undergoing treatment, and therefore, when choosing a radiotherapy treatment method, minimizing radiation dermatitis is an important consideration.

• 한국의학물리학회지:의학물리
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• 제11권2호
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• pp.91-99
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• 2000

본 연구는 선형 가속기에서 나오는 고 에너지 광자빔 조사를 받은 환자 내부의 선량 분포를 조사문 선량 분포로부터 재구성하는 방법을 개발하기 위한 기초 연구로서 삼차원 선량 분포를 재구성하는 방법을 제시하고 이 방법을 전산모사를 통해 평가하였다. 본 연구에서 제안하는 방법은 환자나 팬톰 내부의 임의의 지점에서 흡수된 선량과 그 지점에 대응되는 조사문 선량의 측정 지점에서 흡수된 선량의 차이를 계산하여 측정된 조사문 선량 분포로부터 환자나 팬톰 내부의 선량분포를 얻는 것이다. 선량의 차이는 역제곱법칙과 선형감쇄계수, 그리고 Monte Carlo 프로그램을 이용하여 환자나 팬톰의 CT 정보로부터 계산한 산란선량과 주선량의 비(scatter to primary dose ratio)를 이용하여 계산한다. 이 방법을 시험하기 위해 여러 종류의 균질 혹은 비균질 팬톰의 조사문 선량 분포를 Monte Carlo 전산모사로 계산한 뒤 팬톰 내부의 선량 분포를 재구성하였다. 광자빔은 1.5 MeV의 단일에너지를 사용하였고 Monte Carlo 프로그램은 EGS4를사용하였다. 본 연구의 방법을 사용하여 재구성된 팬톰 내부의 선량 분포와 Monte Carlo로 계산한 팬텀 내부의 선량 분포와 비교하였다. 비교 결과 오차 -4%∼+2% 이내로 일치하였다. 이 방법은 다른 in vivo dosimetry 방법을 대신하여 환자내의 선량분포를 예측하는데 쓰여질 수 있을 것이다.

• Radiation Oncology Journal
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• 제36권1호
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• pp.79-84
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• 2018

Deep inspiration breathing hold (DIBH) compared to free-breathing (FB) during radiotherapy (RT) has significantly decreased radiation dose to heart and has been one of the techniques adopted for patients with breast cancer. However, patients who are unable to make suitable deep inspiration breath may not be eligible for DIBH, yet still need to spare the heart and lung during breast cancer RT (left-sided RT in particular). Continuous positive airway pressure (CPAP) is a positive airway pressure ventilator, which keeps the airways continuously open and subsequently inflates the thorax resembling thoracic changes from DIBH. In this report, authors applied CPAP instead of FB during left-sided breast cancer RT including internal mammary node in a patient who was unable to tolerate DIBH, and substantially decreased radiation dose the heart and lung with CPAP compared to FB.

• 대한방사선치료학회지
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• 제11권1호
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• pp.73-78
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• 1999

In general, the patients of the head and neck cancer are treated with 4MV photon beam up to prescribed dose, but spinal cord should be excluded in the treatment field. When its absorbed dose is limited at the tolerance dose. In case of the patients who has the positive posterior neck nodes need a boost electron beam treatment to the prescribed dose. In that case, the anatomical structure of the neck and the physical structure of the standard electron cone interrupt to allow proper access to the disease site. Therefore, we extended treatment SSD for the remove of the those hindrances. In this study, we evaluated the dosimetric variation of the standard electron cone for the extended SSD, from 100cm to 120cm, 5 cm increment, and compare to the custom-made electron cone. As a result, the $\%$ depth dose, the point of maximum dose and the range of maximum were changed within the $2\%$. The penumbra width was increased from 1.0cm to 2.0cm. However, the dosimetric characteristics of the custom-made electron cone was very similar to that of the 100cm SSD standard electron cone and due to its characteristic of physical structure, patients didn't need re-positioning after photon beam treatment, therefore accurate treatment was possible, we conclude that the custom-made electron cone was very useful for the clinical practice.

• Radiation Oncology Journal
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• 제37권4호
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• pp.286-292
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• 2019

Purpose: A mandibular metastasis is uncommon in patients with hepatocellular carcinoma (HCC). We report the clinical features of this rare lesion and evaluate the effectiveness of radiotherapy in affected patients. Materials and Methods: We retrospectively reviewed our institutional medical records for HCC patients who received radiotherapy for bone metastasis, and included cases of mandible metastasis. The clinical features of these cases, and the characteristics and outcomes of the treatments were assessed. Results: A total of 1,498 patients with a bone metastasis from HCC were treated with radiotherapy between July 1998 and April 2012 at our institution. We identified 9 patients (0.6%) in this cohort that received radiotherapy for a mandibular metastasis. The condyle was the most common location of mandibular metastasis. The median radiation dose was 40 Gy (range, 27.5 to 60 Gy), with a daily dose of 2-3 Gy. All of these 9 patients died during a median follow-up of 9 months (range, 1 to 19 months). Symptom relief was achieved in 7 of 8 patients who completed radiotherapy. Tumor size reduction was observed in 2 of 4 patients who underwent radiologic evaluation after radiotherapy. Conclusions: Metastasis to the mandible from HCC has a poor prognosis. Radiotherapy can be an effective local treatment option for symptomatic relief in these cases.

• Radiation Oncology Journal
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• 제2권1호
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• pp.115-122
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• 1984

Total 125 patinets with primary and metastatic Ewing's sarcoma were treated in various ways between 1963 to 1977. Patients were divided into 3 groups according to the treatment methods. Group 1 was nonprotocol patients with or without chemotherapy. Total 58 patients were entered. Group 1 was divided into 2 subgroups. 33 patients were treated locally without chemotherapy and 25 Patients were treated with local therapy and nonprotocol chemotherapy. Group 2 was treated with local therapy and plus T-2 regimen multiagent chemotherapy. 29 patients were entered. Group 3 was treated with local therapy and T-6 regimen multiagent chemotherapy. 38 patients were entered. Local treatments for primary tumor were surgery and/or radiation therapy. Radiation dose ranged between 2,000 and 8,000 rad. Patients with pulmonary metastases received bilateral pulmonary RT. Local recurrence rate was analyzed according to treatment groups and was $16.8\%$. Local 15 yr survival was $33\%$ and 8 yr survival of T-6 group was $64.9\%$. An analysis of time were pattern of recurrence of each group, and the correlation of with radiation dose with local recurrence done. This study concluded that intensive multiagent chemotherapy RT and/or surgery (T-6 regimen) reduced distant metastases, and produced significant increase in local control and survival.

• 디지털산업정보학회논문지
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• 제10권3호
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• pp.41-48
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• 2014

This paper provides the design of system software for the management of radiation dose that is generated by using computerized tomography(CT). Recently, the radiation leakage incident of Japanese nuclear power plant was in the news internationally and there is a growing interest not only in nuclear power plant but in medical radiation exposure. In spite of the fact that currently safety management of radiation is under control only the workers of the radiation involved, now the exposure management of patients have been required. As surgery and inspections using the radiation have increased, this medical radiation exposure is increasing too. But it is a real situation that medical institutions don't know the level of radiation exposure applied to the patient. Therefore, a system for managing the radiation exposure of a patient from the medical institution is required. This paper proposes a design of a software program that manages the radiation exposure of CT which is a typical imaging tool to use the radiation in the medical institution. By check the amount of radiation dose and set the limit of dose, we would be of help to optimize the medical exposure of the patient.

• Radiation Oncology Journal
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• 제31권1호
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• pp.34-40
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• 2013

Purpose: To evaluate the predictive factors of radiation pneumonitis (RP) and associated changes in pulmonary function after definitive concurrent chemoradiotherapy (CCRT) in patients with non-small cell lung cancer (NSCLC). Materials and Methods: Medical records of 60 patients with NSCLC who received definitive CCRT were retrospectively reviewed. Dose volumetric (DV) parameters, clinical factors, and pulmonary function test (PFT) data were analyzed. RP was graded according to the CTCAE ver. 4.0. Percentage of lung volume that received a dose of threshold (Vdose) and mean lung dose (MLD) were analyzed for potential DV predictors. PFT changes were calculated as the difference between pre-RT and post-RT values at 3, 6, and 12 months after RT. Results: Twenty-two patients (37%) developed grade ${\geq}2$ RP. Among clinical factors, tumor location in lower lobe was associated with RP. Among the DV parameters, only MLD >15 Gy was associated with grade ${\geq}2$ RP. There were statistically significant decreases in PFT at all points compared with pre-RT values in grade ${\geq}2$ RP group. MLD was associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) changes at 6 and 12 months. V10 was associated with FVC changes at 12 months. V20 and V30 were associated with FEV1 changes at 6 months and FVC changes at 12 months. Conclusion: After definitive CCRT in patients with NSCLC, MLD >15 Gy and lower lobe tumor location were predictors of grade ${\geq}2$ RP. Pulmonary functions were decreased after CCRT and the magnitude of changes was associated with DV parameters.

• 한국의학물리학회지:의학물리
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• 제34권1호
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• pp.10-13
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• 2023

Patients with breast cancer can be positioned with their head turned to the contra lateral side or with their head straight during the radiation therapy treatment set-up. In our hospital, patients with locally advanced breast cancer who were receiving radiation therapy have experienced swallowing difficulty after 2 weeks of irradiation. In this pilot study, the impact of head position on reducing dysphagia occurrence was dosimetrically evaluated. Patients were divided into two groups viz., HT (head turned to the contra lateral side of the breast) and HS (head straight) with 10 members in each. Treatment planning was performed, and the dosimetric parameters such as Dmin, Dmax, Dmean, V₅, V₁₀, V₂₀, V₃₀, V₄₀, and V₅₀ of both groups were extracted from the dose volume histogram (DVH) of esophagus. The target coverage in the supraclavicular fossa (SCF) region was analyzed using D₉₅ and D₉₈; moreover, the dose heterogeneity was assessed with D₂ from the DVHs. The average values of the dose volume parameters were 27.6%, 58.6%, 35.4%, 19%, 13.8%, 14.1%, 11.8%, 8.4%, and 8.1% higher in the HT group compared with those in the HS group. Furthermore, for the SCF, the mean values of D₉₈, D₉₅, and D₂ were 42.4, 47.5, and 54 Gy, respectively, in the HS group and 38.9, 45.35, and 55.5 Gy, respectively, in the HT group. This pilot study attempts to give a solution for the poor quality of life of patients after breast radiotherapy due to dysphagia. The findings confirm that the head position could play a significant role in alleviating esophageal toxicity without compromising tumor control.