• Radiation Oncology Journal
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• 제18권1호
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• pp.1-10
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• 2000

목적 : 비인강암에서 방사선치료는 근치적 목적으로 사용되고 있으나 방사선치료 후 이하선 기능 저하에 따른 구강 건조증이 생기는 것이 문제이다. 방사선치료에 의한 구강 건조증의 발생을 감소시키기 위해 방사선조사시 이하선을 보호하는 새로운 치료 기법을 개발하고자 하였다. 대상 및 방법 : 림프절 전이가 없고 종양의 침범 범위가 서로 상이한 비인강암 4례를 대상으로 2가지의 새로운 치료계획을 수립하고 기존의 2차원 통상치료계획과 비교하였다. 치료계획-A는 기존의 2차원 통상치료 방법이며, 치료계획-B는 져 Gy 이후에 축소조사를 3차원 입체 조형치료로 하는 것이며, 치료계획-C는 방사선 치료 처음부터 3차원 입체 조형치료를 이용하여 양측 이하선을 방사선 조사영역에서 제외시키면서 30.6 Gy에서 척수 차폐를 시행하고 져 Gy 이후에 축소조사시 비동일 평면 3차원 입체조형치료를 시행하는 방법이다. 위 3가지 치료계획은 모두 70.2 Gy의 선랸을 계획용 표적체적내 회전중심점에 처방하여 각 치료계획마다 계획용 표적체적과 이하선의 등선량 분포, 선량체적 히스토그람(dose volume histogram, DVH), 선량통계(dose statistics), 정상조직손상확률(normal tissue complication probability, NTCP)을 비교하였다. 결과 : 전 예의 환자에서 치료 표적 부위의 등선량 분포, 선량통계와 선량체적 히스토그람상 치료계획-C에서 치료선량이 표적체적 내에 보다 균일하게 조사되었다. 선량통계분석에서 이하선에 조사되는 평균 방사선량은 치료계획-C에서 가장 적었으며(치료계획-A 58 Gy, 치료계획-B 50 Gy, 치료계획-C 48.5 Gy), 46 Gy가 조사되는 체적도 가장 적었다(치료계획-A 100$\%$, 치료계획-B 98$\%$, 치료계획-C 69$\%$). 선량체적 히스토그람도 치료계획-C에서 가장 우수하였고, 선량체적 히스토그람을 이용하여 계산된 정상조직 부작용 확률도 치료계획-C에서 가장 낮았다. 결론 : 방사선치료 초기부터 3차원 입체조형치료를 적용하여 이하선을 치료 조사영역에서 제외하고, 축소 조사시에 다양한 조사방향을 가능하게 하기 위해 45 Gy 이전에 척수 차폐(spinal cord block)를 적용하는 이 같은 새로운 방사선치료 기법이 림프절 전이가 없는 비인강암의 환자에서 구강 건조증 발생을 감소시키는 방사선치료기법으로 추천될 수 있다고 사료된다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.2051-2054
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• 2015

Background: Radiation therapy is a key part of the combined modality treatment for Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL), which can achieve locoregional control of disease. The 3D-conformal radiation oncology can be extended-field (EFRT), involved-field (IFRT) and involved node (INRT). New techniques have resulted in a smaller radiation field and lower dose for critical organs such as lung heart and breast. Materials and Methods: In our research, we made a virtual simulation for one patient who was treated in four different radiotherapeutic techniques: mantle field (MFRT), EFRT, IFRT and INRT. After delineatiion we compared dose-volume histograms for each technique. The fusion of CT for planning radiotherapy with the initial PET/CT was made using Softver Xio 4.6 in the Focal program. The dose for all four techniques was 36Gy. Results: Our results support the use of PET/CT in radiation therapy planning. With IFRT and INRT, the burden on the organs at risk is less than with MFRT and EFRT. On the other hand, the dose distribution in the target volume is much better with the latter. Conclusions: The aim of modern radiotherapy of HL and NHL is to reduce the intensity of treatment and therefore PET/CT should be used to reduce and not increase the amount of tissue receiving radiation.

• 대한방사선기술학회지:방사선기술과학
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• 제42권6호
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• pp.413-422
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• 2019

Heavy ion particle, represented carbon ion, radiotherapy is currently most advanced radiation therapy technique. Conventional radiation therapy has made remarkable changes over a relatively short period of time and leading various developments such as intensity modulated radiation therapy, 4D radiation therapy, image guided radiation therapy, and high precisional therapy. However, the biological and physical superiority of particle radiation, represented by Bragg peak, can give the maximum dose to tumor and minimal dose to surrounding normal tissues in the treatment of cancers in various areas surrounded by radiation-sensitive normal tissues. However, despite these advantages, there are some limitations and factors to consider. First, there is not enough evidence, such as large-scale randomized, prospective phase III trials, for the clinical application. Secondly, additional studies are needed to establish a very limited number of treatment facilities, uncertainty about the demand for heavy particle treatment, parallel with convetional radiotherapy or indications. In addition, Bragg peak of the heavy particles can greatly reduce the dose to the normal tissues front and behind the tumor compared to the photon or protons. High precision and accuracy are needed for treatment planning and treatment, especially for lungs or livers with large respiratory movements. Currently, the introduction of the heavy particle therapy device is in progress, and therefore, it is expected that more research will be active.

• 대한두경부종양학회지
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• 제26권1호
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• pp.27-29
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• 2010

Tracheostomal stenosis after total laryngectomy is brothersome problem to surgeon and patient. To prevent tracheostomal stenosis, tension around the tracheostoma must be released. Advancement flap, V-Y inset and Z-plasty were suggested as solution to tracheostomal stenosis. But such methods need elevation of superior flap and it is very difficult when the patients received radiotherapy and has high change of developing pharyngocutaneous fistula. We suggested new stomaplasty technique which named "Modified Fish-Mouth Technique" that does not need to elevate superior skin flap.

• Radiation Oncology Journal
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• 제18권3호
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• pp.167-176
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• 2000

최근의 방사선치료는 치료의 질을 향상시켜서 치료 후의 삶의 질을 높이는 것을 목표로 하고 있다. 국내에서도 방사선치료 환자와 치료 시설의 빠른 증가로 방사선종양학 분야는 많은 발전이 되고 있으며, 치료기술 또한 3-dimensional conformal radiotherapy의 보편화, liuac based stereotactlc radiosurgery의 활발한 적용과 luteuslty modulated radiation tferapy (IMRT)의 도입 준비 등 고난도의 치료 기술도입이 시도되고 있다. 저자는 최근 20년간 한국에서의 방사선 종양학의 발전을 조망하고 최근 발전되는 4차원적 방사선치료, IMRT의 현황, blologlcai conformailty치료의 개념, 항암제와 방사선치료의 병용에 대하여 살펴보고 최근 정보기술 혁명에 따른 인터넷과 방사선종양학 분야의 정보관리 시스템의 중요성 및 원격진료의 세계적 현황 등에 대해서 알아보고, 21 세기 한국에서의 방사선치료의 질을 올리기 위한 방법들을 제시하였다. 이들은 1) OA (qualify assurance) 향상, 2) 공동 프로토콜에 의한 3상 임상 연구의 필요성, 3) 특정 암에 대한 통일된 치료 프로토콜 또는 가 이드라인, 4) 전국적인 방사선종양학 관련 자료의 광역 data base구축과 중요 암에 대한 patterns of care study 등 시행의 필요성이다

• Radiation Oncology Journal
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• 제38권2호
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• pp.109-118
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• 2020

Purpose: Hypofractionated radiotherapy (RT) is becoming a new standard in postoperative treatment of patients with early stage breast cancer after breast conservation surgery. However, data on hypofractionation in patients with advanced stage disease who undergo mastectomy followed by local and regional nodal irradiation (RNI) is lacking. In this retrospective study, we report late-term effects of 3 weeks post-mastectomy hypofractionated local and RNI with two-dimensional (2D) technique in patients with stage II and III breast cancer. Methods: Between January 1990 and December 2007, 1,770 women with breast cancer who were given radical treatment with mastectomy, systemic therapy and RT at least 10 years ago were included. RT dose was 35 Gy/15 fractions/3 weeks to chest wall by two tangential fields and 40 Gy in same fractions to supraclavicular fossa (SCF) and internal mammary nodes (IMNs). SCF and IMNs dose was prescribed at d_max and 3 cm depth, respectively. Chemotherapy and hormonal therapy was given in 64% and 74% patients, respectively. Late-term toxicities were assessed with the Radiation Therapy Oncology Group (RTOG) scores and LENT-SOMA scales (the Late Effects Normal Tissue Task Force-Subjective, Objective, Management, Analytic scales). Results: Mean age was 48 years (range, 19 to 75 years). Median follow-up was 12 years (range, 10 to 27 years). Moderate/marked arm/shoulder pain was reported by 254 (14.3%) patients. Moderate/marked shoulder stiffness was reported by 219 (12.3%) patients. Moderate/marked arm edema was seen in 131 (7.4%) patients. Brachial plexopathy was not seen in any patient. Rib fractures were noted in 6 (0.3%) patients. Late cardiac and lung toxicity was seen in 29 (1.6%) and 23 (1.3%) patients, respectively. Second malignancy developed in 105 (5.9%) patients. Conclusion: RNI with 40 Gy/15 fractions/3 weeks hypofractionation with 2D technique seems safe and comparable to historical data of conventional fractionation (ClinicalTrial.gov Registration No. NCT04175821).

• 한국의학물리학회지:의학물리
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• 제34권4호
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• pp.48-54
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• 2023

Purpose: In this study, the dosimetric characteristics of lung stereotactic body radiotherapy (SBRT) plans using the new Halcyon system were analyzed to assess its suitability. Methods: We compared the key dosimetric parameters calculated for the Halcyon SBRT plans with those of a conventional C-arm linear accelerator (LINAC) equipped with a high-definition multileaf collimator (HD-MLC)-Trilogy Tx. A total of 10 patients with non-small-cell lung cancer were selected, and all SBRT plans were generated using the RapidArc technique. Results: Trilogy Tx exhibited significant superiority over Halcyon in terms of target dose coverage (conformity index, homogeneity index, D_{0.1 cc}, and D_95%) and dose spillage (gradient). Trilogy Tx was more efficient than Halcyon in the lung SBRT beam delivery process in terms of the total number of monitor units, modulation factor, and beam-on time. However, it was feasible to achieve a dose distribution that met SBRT plan requirements using Halcyon, with no significant differences in satisfying organs at risk dose constraints between both plans. Conclusions: Results confirm that Halcyon is a viable alternative for performing lung SBRT in the absence of a LINAC equipped with HD-MLC. However, extra consideration should be taken in determining whether to use Halcyon when the planning target volume setting is enormous, as in the case of significant tumor motions.

• Journal of Korean Neurosurgical Society
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• 제63권4호
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• pp.415-426
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• 2020

Arteriovenous malformations (AVMs) are congenital anomalies of the cerebrovascular system. AVM harbors 2.2% annual hemorrhage risk in unruptured cases and 4.5% annual hemorrhage risk of previously ruptured cases. Stereotactic radiosurgery (SRS) have been shown excellent treatment outcomes for patients with small- to moderated sized AVM which can be achieved in 80-90% complete obliteration rate with a 2-3 years latency period. The most important factors are associated with obliteration after SRS is the radiation dose to the AVM. In our institutional clinical practice, now 22 Gy (50% isodose line) dose of radiation has been used for treatment of cerebral AVM in single-session radiosurgery. However, dose-volume relationship can be unfavorable for large AVMs when treated in a single-session radiosurgery, resulting high complication rates for effective dose. Thus, various strategies should be considered to treat large AVM. The role of pre-SRS embolization is permanent volume reduction of the nidus and treat high-risk lesion such as AVM-related aneurysm and high-flow arteriovenous shunt. Various staging technique of radiosurgery including volume-staged radiosurgery, hypofractionated radiotherapy and dose-staged radiosurgery are possible option for large AVM. The incidence of post-radiosurgery complication is varied, the incidence rate of radiological post-radiosurgical complication has been reported 30-40% and symptomatic complication rate was reported from 8.1% to 11.8%. In the future, novel therapy which incorporate endovascular treatment using liquid embolic material and new radiosurgical technique such as gene or cytokine-targeted radio-sensitization should be needed.

• Journal of Medicine and Life Science
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• 제16권1호
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• pp.23-26
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• 2019

Total scalp irradiation is a challenging treatment because of unique concave target volume and difficulty with bolus applying. There are few reports about bolus applying methods to the entire scalp in detail. Application of conventional bolus (wax or superflab) is widely used, and it is considered effective. However, the curvature and irregularity of the scalp can produce significant air gap, resulting in inadequate radiation dose distribution. We describe a new method to applying the bolus to the entire scalp. We sutured 1 cm thickness superflab bolus on the thermoplastic mask using cotton string. This method can reduce the air gap between the bolus and scalp and be reproducible.

• 한국의학물리학회지:의학물리
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• 제18권1호
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• pp.27-34
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• 2007

호흡운동 조절 방사선치료 시 환자체표면 움직임을 추적하여 실시간 보정하고자 한다. 본 연구에서 사용한 시스템은 치료테이블에 기반을 둔 동 팬텀(CBMP, couch based computer-controlled motion phantom), 초음파 센서 및 제어, 구동, 분석 프로그램 등으로 구성하였다 동물실험 결과 호흡주기는 2.9초이었고, 호흡진폭은 6mm이었다. 실시간 체표면 추적시스템의 유용성 평가에 중요한 항목인 호흡운동 획득-보정간의 지연시간은 $2.34{\times}10^{-4}sec$ 초이어서 호흡운동 조절 방사선치료 시 사용할 수 있는 새로운 실시간 체표면 추적 기술의 임상적용에의 가능성을 확인할 수 있었다.