소아뇌종양의 방사선치료

임도훈 대한의사협회 2012 대한의사협회지 Vol.55 No.5

Pediatric brain tumors present a tremendous challenge to physicians due to their diverse biologic behavior and the developing nervous system. Therefore, flexible and tailored treatment plans are required. Radiation therapy has played an important role in pediatric brain tumors and treatment results have improved. However, to reduce late radiation effects, the modification of the radiation dose and volume with intensified chemotherapy or delay of radiotherapy is the concept of current protocols. With the results of many clinical trials, the understanding of radiation-induced neurotoxicity has progressed, and there have been technical advances in the field of radiotherapy such as image-guided radiation therapy and intensity-modulated radiation therapy. To achieve disease control as well as functional outcomes for children with brain tumors, further studies using high precision radiotherapy combined with other modalities will be needed.

Study on Characteristics of Ecology of Fishes and Benthic Macroinvertebrates in Namgang Dam Reservoir, Korea

임도훈,이윤진 한국환경보건학회 2018 한국환경보건학회지 Vol.44 No.6

Objectives: We aimed to investigate the species composition of fish and benthic macroinvertebrates in the Namgang Dam reservoir and assess the reservoir’s ecological quality. Methods: Fish and benthic macroinvertebrates were seasonally sampled around the Namgang Dam reservoir from October 2013 to September 2014. Results: A total of 970 fish specimens were collected for this survey, including 4 orders, 14 families, and 25 species. Fourteen endemic species were observed, including Coreoleuciscus splendidus. The most observed among the endemic species caught was Zacco koreanus (14.4%). A total of 9,093 benthic macroinvertebrates, including 51 families and 92 species, were also found. The predominant species in the study area was Chironomidae sp. 1. Diplonychus esakii, whose habitat is distribution-specific as designated by the Korean National Institute of Environmental Research (NIER), were also observed. A total of 386 specimens were collected of the invasive alien species Lepomis macrochirus, and the percentage of Lepomis macrochirus and Micropterus salmoides made up 42.0% of all specimens collected in the area. Conclusion: The mean ecological score of the benthic macroinvertebrate community (ESB) ranged between 24 and 40, which indicates that the environmental condition of the target sites is somewhat poor. Based on the results of this research, building habitats for benthic macroinvertebrates should be considered, and extermination plans for invasive alien fish species should be prepared.

Postoperative Adjuvant Radiotherapy for Patients with Gastric Adenocarcinoma

임도훈 대한위암학회 2012 Journal of gastric cancer Vol.12 No.4

In gastric adenocarcinoma, high rates of loco-regional recurrences have been reported even after complete resection, and various studies have been tried to find the role of postoperative adjuvant therapy. Among them, Intergroup 0116 trial was a landmark trial, and demonstrated the definite survival benefit in adjuvant chemoradiotherapy, compared with surgery alone. However, the INT 0116 trial had major limitation for global acceptance of the INT 0116 regimen as an adjuvant treatment modality because of the limited lymph node dissection. Lately, several randomized studies that were performed to patients with D2-dissected gastric cancer were published. This review summarizes the data about patterns of failure after surgical resection and the earlier prospective studies, including INT 0116 study. Author will introduce the latest studies, including ARTIST trial and discuss whether external beam radiotherapy should be applied to patients receiving extended lymph node dissection and adjuvant chemotherapy.

Evaluation of Water Quality Characteristics and Ecosystem Health of Yongpung Reservoir, Korea

임도훈,이윤진,김경 한국환경보건학회 2019 한국환경보건학회지 Vol.45 No.1

Objectives: The Yongpung reservoir in Korea is a crucial facility that supplies water to farms in its surrounding 2 km 2 area. However, its water quality is not suited to the needs of current residents who wish for the availability of environmentally friendly agricultural products and desire to use the waterfront area. The aim of this research was to evaluate the reservoir’s fish and benthic macroinvertebrate distributions and determine its water quality and the heavy metal content in its sediment. This basic data can be used to establish environmentally protective plans for the Yongpung reservoir. Methods: Six sites were selected for analysis in this investigation. Three points (YP-1, YP-2, and YP-3) were evaluated for water quality and metal content in sediments; they were located upstream, midstream, and downstream of the reservoir. Samplings of the fish and benthic macroinvertebrate populations were performed at three other sites: St. 1, St. 2, and St. 3. Results: Based on chemical oxygen demand (COD) and total nitrogen (T-N) data, the quality of the Yongpung reservoir water corresponds to Class VI (very poor) according to Korea’s lake environmental standards. The lead levels measured in the sediment at the midstream and downstream points of the reservoir were 76.7 and 72.7 mg/kg, respectively, while 8 orders, 15 families, and 16 species of benthic macroinvertebrates were identified in the reservoir. The ecological score of the benthic macroinvertebrate community (ESB) was between 8 and 23, denoting poor to very poor environmental conditions. Further, 4 families and 7 species of fish were identified in the reservoir, with Cyprinidae accounting for 94.3% of all observed freshwater fish. Conclusion: Based on these findings, we conclude that management plans, including the removal of lead from the sediment, are necessary to improve the quality of the agricultural water in this reservoir. The T. japonica, which cover almost 30% of the water area, must also be removed.

Clinical Outcomes of Moderately Hypofractionated Concurrent Chemoradiotherapy for Newly Diagnosed Glioblastoma

임도훈,김나리,최정원,이정일,공두식,설호준,남도현 연세대학교의과대학 2023 Yonsei medical journal Vol.64 No.2

Purpose: Hypofractionated radiotherapy (HypoRT) has recently been implemented in patients with glioblastoma (GBM) receiv ing concurrent temozolomide. Lymphopenia during treatment (LDT) is considered an important prognostic factor of clinical outcomes for GBM. We aimed to investigate the outcomes of HypoRT. Materials and Methods: Among 223 patients with GBM, 145 and 78 were treated with conventionally fractionated RT (ConvRT, 60 Gy in 30 fractions) and HypoRT (58.5 Gy in 25 fractions), respectively. To balance characteristics between the two groups, pro pensity score matching (PSM) was performed. Results: Patients in the HypoRT group were older and had smaller tumors than those in the ConvRT group (p<0.05). Further more, dose distributions to the brain were significantly lower in HypoRT than in ConvRT (p<0.001). Changes in absolute lympho cyte counts (ALC) during treatment were significantly lower after HypoRT than after ConvRT (p=0.018). With a median follow-up of 16.9 months, HypoRT showed comparable progression-free survival (9.9 months vs. 10.5 months) and overall survival (27.2 months vs. 26.6 months) to ConvRT (all p>0.05). Multivariable analysis before PSM revealed that ≥grade 2 LDT at 6 months was associated with inferior outcomes. Subsequent analysis demonstrated that HypoRT significantly reduced the rate of ≥grade 2 LDT at 6 months post-RT before and after PSM. Conclusion: HypoRT with 58.5 Gy in 25 fractions could provide comparable oncologic outcomes and significantly reduce the ALC changes. In addition, HypoRT decreased the LDT. Further investigation should be warranted to suggest the significance of reduced LDT through HypoRT affecting survival outcomes.

췌담도암 방사선치료의 최신 지견

임도훈 대한췌담도학회 2012 대한췌담도학회지 Vol.17 No.1

A Study on the Distribution Characteristics and Countermeasures of Concentrations of Ambient PM10 and PM2.5 in Yangju, South Korea

임도훈,이윤진 대한자원환경지질학회 2022 자원환경지질 Vol.55 No.6

This study investigated the distribution behaviors of PM2.5 and PM10 at two air quality monitoring sites, Go-eup (GO) and Backseokeup (BS), located in Yangju City, South Korea. The amounts of emissions sources of pollutants were analyzed based on the Clean Air Policy Support System (CAPSS), and the contribution rates of neighboring cities were enumerated in Yangju. Yangju has a geological basin structure, and it is a city with mixed urban and rural characteristics. The emission concentration of particulate matter was affected by geological and seasonal factors for all sites observed in this study. Therefore, these factors should be considered when establishing policies related to particulate matter. Because the official GO and BS station sites in Yangju are both situated in the southern part of the city, the representativeness of both stations was checked using correlation analysis for the measurement of PM2.5 and PM10 by considering two more sites—those of Bongyang-dong (BY) and the Gumjun (GJ) industrial complex. The data included discharge amounts for business types 4 and 5, which were not sufficiently considered in the CAPSS estimates. Because the 4 and 5 types of businesses represent over 92.6% of businesses in this city, they are workplaces in Yangju that have a significant effect on the total air pollutant emission. These types of businesses should be re-inspected as the main discharge sources in industry, and basic data accumulation should be carried out. Moreover, to manage the emission of particulate matter, attainable countermeasures for the main sources of these emissions should be prepared in a prioritized fashion; such countermeasures include prohibition of backyard burning, supervision of charcoal kilns, and management of livestock excretions and fugitive dust in construction sites and on roads. The contribution rates by neighboring cities was enumerated between 6.3% and 10.9% for PM2.5. Cooperation policies are thought to be required with neighboring cites to reduce particulate matter.

골반부 방사선 조사야 내의 소장 용적을 줄이기 위한 Small Bowel Displacement System(SBDS)의 사용

임도훈(Do Hoon Lim),허승재(Seung Jae Huh),안용찬(Yong Chan Ahn),김대용(Dae Yong Kim),우홍균(Hong Gyun Wu),김문경(Moon Kyung Kim),최동탁(Dong Rak Choi),신경환(Kyung Hwan Shin) 대한방사선종양학회 1997 Radiation Oncology Journal Vol.15 No.3

Purpose : Authors designed a customized Small Bowel Displacement System (SBDS) to displace the small bowel from the pelvic radiation fields and minimize treatment-related bowel morbidities. Methods and Materials : From August 1995 to May 1996, 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized styrofoam compression device which can displace the small bowel from the radiation fields and an individualized immobilization abdominal board for easy daily setup in prone position. After opacifying the small bowel with Barium , the patients were laid prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The areas of the small bowel included in the radiation fields with and without the SBDS were compared. Results : Using the SBDS, the mean small bowel area was reduced by 59% on PA and 51% on LAT films (P=0.0001). In six patients (6/55, 11%), it was possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Only 15% (8/55) of patients treated with the SBDS manifested diarrhea requiring medication. Conclusion : The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and reduce the radiation therapy morbidities. Compliance with setup is excellent when the SBDS is used. 목 적 : 저자들은 골반부 방사선 치료에 있어서 소장을 방사선 조사야 밖으로 밀어냄으로써 방사선치료로 인한 소장의 부작용을 최소화하고자 Small Bowel Displacement System (SBDS)을 만들어 환자 치료에 적용하였다. 대상 및 방법 : 1995년 8월부터 1996년 5월까지 SBDS를 이용하여 골반부에 방사선 치료를 받은 55명의 환자를 대상으로 하였다. SBDS는 환자의 하복부를 눌러줌으로써 골반부 내의 소장을 방사선 조사야 밖으로 밀어내는 Styrofoam compression device와 이로 인한 환자의 하복부 불편감을 줄이며 치료시 환자 자세의 안전성을 유지시키기 위해 환자 개개인별로 만든 Immobilization device로 구성된다. 모의치료시 소장을 조영제로 조영시킨 후 복와위 상태에서 SBDS 를 사용하기 전과 사용한 후의 후방-전방 및 측방 촬영을 하여 방사선 조사야 내에 포함되는 조영제로 조영이 되는 소장의 면적을 측정하여 서로 비교하였다. 결 과 : SBDS를 사용했을 때 사용전에 비하여 후방-전방 촬영 필름에서는 59%의 소장이 그리고 측방 촬영 필름에서는 51%의 소장이 방사선 조사야 밖으로 밀려났다(P=0.0001). 조영된 소장의 평균 상향 이동 거리는 4.8cm였으며, 55명의 환자중 단지 8명 (15%)에서만 투약이 필요할 정도의 설사를 호소하였으며, 이로 인하여 방사선치료가 중단되거나 지연된 경우는 없었다. 결 론 : SBDS는 소장을 골반부 방사선 조사야 밖으로 효과적으로 밀어내는 기구로서 방사선 치료로 인한 소장의 부작용을 감소시키는 기구이다. 또한, 제작이 용이하며 환자 치료 자세의 높은 재현성을 보였다. SBDS를 사용한 환자에서 향후 방사선 만성 부작용의 발생 빈도 감소에 기여한다면 필요한 경우에 골반부에 조사하는 방사선량을 증가시켜 보다 향상된 치료효과를 기대할 수 있겠다.

정위방사선치료 시 적분 생물학적 유효선량 및 방사선조사용적을 이용한 Total Arc Degree 의 최적화

임도훈(Do Hoon Lim),이명자(Myung Za Lee),전하정(Ha Chung Chun),김대용(Dae Yong Kim) 대한방사선종양학회 2001 Radiation Oncology Journal Vol.19 No.2

목 적 :정위방사선치료 시 정상 뇌 조직을 고선량의 방사선으로부터 최대한 보호하며 치료의 효율성을 높이기 위하여 치료 인자 중 콜리메이터의 크기와 arc 간 간격에 따른 이상적인 total arc degree (TAD) 값을 제시하고자 한다. 대상 및 방법 :XKnife-3 planning system을 사용하여 환자의 송과체 부위에 방사선 빔의 회전중심점을 위치시킨 후 12, 20, 30, 40, 50 그리고 60 mm 직경의 정위방사선치료용 원형 콜리메이터를 이용하여 각각의 콜리메이터 직경별로 TAD를 100, 200, 300, 400, 500, 600도, 그리고 arc 간 간격을 30도(6- arc system)와 45도(4- arc system)로 설정하여 방사선치료계획을 수립하였다. 치료계획을 통해 얻은 누적선량체적히스토그람을 이용하여 회전중심점 처방선량의 50% 이상 조사되는 정상 뇌의 용적(V50) 및 적분 생물학적 유효선량(integral biologically effective dose)을 이용하여 각각의 TAD에 따른 방사선치료계획을 비교하였다. 결 과 :TAD에 따른 V50의 변화는 arc 간 각도가 30도인 경우에는 콜리메이터 직경과 관계없이 TAD가 증가할수록 감소하는 양상을 보였으나, 45도의 arc 간 각도에서는 400도의 TAD까지는 감소하다가 400도 이상의 TAD에서 V50은 증가하거나 변화가 없었다. 적분 생물학적 유효선량 값의 변화는 arc 간 간격이 30도인 경우에는 콜리메이터의 직경에 관계없이 TAD가 증가함에 따라 미소하게 감소하는 양상을 보였다. arc 간 각도가 45도인 경우에는 콜리메이터 직경이 40 mm 이하에서는 TAD가 증가함에 따라 적분 생물학적 유효선량은 계속 감소하였으나, 50 mm와 60mm 직경의 콜리메이터에서는 TAD가 400도까지는 감소하다가 500도 이상의 TAD에서는 증가하였다. 결 론 :정위방사선치료 시 400도 정도의 TAD를 사용하는 것은 300도 이하 혹은 500도 이상의 TAD를 사용하는 것보다 치료 효과를 높이면서 치료계획과 치료 시 장비 및 인적 자원의 효율적인 운용을 기대할 수 있을 것으로 판단된다. Purpose : To find the optimal values of total arc degree to protect the normal brain tissue from high dose radiation in stereotactic radiotherapy planning Methods and Materials :With Xknife- 3 planning system & 4 MV linear accelerator, the authors planned under various values of pa rameters . One isocenter, 12, 20, 30, 40, 50, and 60 mm of collimator diameters , 100˚, 200˚, 300˚, 400˚, 500˚, 600˚ of total arc degrees , and 30˚ or 45˚ of arc intervals were used. After the completion of planning, the plans were compared each other us ing V50 (the volume of normal bra in that is delivered high dose radiation) and integral biologically effective dose. Results :At 30˚ of a rc interva l, the values of V50 had the decreased pattern with the increase of total arc degree in any collimator diameter. At 45˚ a rc interva l, up to 400˚ of total arc degree, the values of V50 decreased with the increase of tota l arc degree, but at 500˚ and 600˚ of total arc degrees , the values increased. At 30˚˚of arc interval, integral biologica lly effective dose showed the decreased pattern with the increase of tota l arc degree in any collimator diameter. At 45˚ arc interval with less than 40 mm collimator diameter, the integra l biologically effective dose decreased with the increase of tota l arc degree, but with 50 and 60 mm of collimator diameters , up to 400˚ of total arc degree, integral biologically effective dose decreased with the increase of total a rc degree, but at 500˚ and 600˚ of total arc degrees , the values increased. Conclusion : In the stereotactic radiotherapy planning for brain les ions , planning with 400˚ of tota l arc degree is optimal. Especially, when the larger collimator more than 50 mm diameter should be used, the uses of 500˚ and 600˚ of total arc degrees make the increase of V50 and integral biologica lly effective dose. Therefore stereotactic radiotherapy planning us ing 400˚ of total arc degree can increase the therapeutic ratio and produce the effective outcome in the management of personal and mechanical sources in radiotherapy department.

작은 크기의 재발성 간세포암에 대한 구제치료로 소분할 방사선치료 : 국소 제어율과 안전성

배선현(Sun Hyun Bae) · 박희철(Hee Chul Park) · 임도훈(Do Hoon Lim) · 이정애(Jung Ae Lee) · 최문석(Moon Seok Choi) · 이준혁(Joon Hyoek Lee) · 고광철(Kwang Cheol Koh) · 백승운(Seung Woon Paik) · 유병철(Byung Chul Yoo) 대한방사선종양학회 2010 Radiation Oncology Journal Vol.28 No.2

목 적: 크기가 작은 5 cm 미만의 재발성 간세포암 환자를 대상으로 소분할 방사선치료 후 종양의 반응, 국소제어율 및 소분할 방사선치료와 연관된 부작용을 평가하였다.대상 및 방법: 2006년부터 2007년까지 국소요법으로 치료한 후 재발한 간세포암 환자 중 구제치료로 소분할 방사선치료를 받은 12명의 환자를 대상으로 후향적 분석을 시행하였다. 소분할 방사선치료의 적용기준은 종양의 크기가 5 cm 미만이고, 중요 정상조직에 인접하지 않으면서, 간세포암에 의한 간문맥 종양 혈전증이 없으며, 처방된방사선량의 50%가 조사되는 정상 간 용적이 15% 미만인 경우로 제한하였다. 소분할 방사선치료의 1회 조사량은5 Gy였고, 주 5회 치료하여 2주 동안 총 50 Gy를 조사하였다. 종양의 반응도는 방사선치료 종료 후 3개월에 시행된 간 컴퓨터단층촬영으로 평가하였다. 치료와 연관된 부작용은 Common Terminology Criteria for Adverse Eventsversion 3.0으로 평가하였다. 방사선치료 종료 후 추적관찰기간은 8∼33개월(중앙값 18개월)이었다. 결 과: 방사선치료 후 3개월에 시행한 간 컴퓨터단층촬영에서 완전관해율은 41.7%였고 추적관찰기간에 확인한 전체 완전관해율은 58.3%였다. 방사선치료 부위 내 국소제어율은 83.3%였다. 두 명을 제외한 모든 환자에서 간 내재발이 발생하였다. 전체 환자의 1년 및 2년 생존율은 각각 90.0%, 67.5%였다. 치료와 연관된 부작용은 3명의 환자가 치료 중 1도의 오심, 식욕부진이 발생하였고 방사선치료 종료 후 복수가 진행한 환자가 1명 있었다. 3도 이상의 중대한 부작용은 없었다. 결 론: 작은 크기의 재발성 간세포암의 구제 치료로서 소분할 방사선치료는 58.3%의 완전관해율과 83.3%의 국소제어율을 보여주었다. 소분할 방사선치료로 5 Gy씩 총 50 Gy를 조사하는 것은 치료와 연관된 심각한 독성 없이 비교적 안전하고 효과적인 방법으로 판단된다. Purpose: To evaluate the rate of tumor response, local control, and treatment-related complications after hypofractionated radiotherapy for recurrent hepatocelluar carcinoma (HCC) less than 5 cm in size. Materials and Methods: Among the HCC patients who were treated by radiotherapy (RT) between 2006 and 2007 after the failure of previous treatment, a total of 12 patients were treated with hypofractionated RT. The criteria for typofractionated RT was as follows: 1) HCC less than 5 cm, 2) HCC not adjacent to a critical organ, 3) HCC without portal vein tumor thrombosis, and 4) less than 15% of normal liver volume that irradiated 50% of the prescribed dose. Hypofractionated RT was performed with 50 Gy delivered in 10 fractions, at a rate of 5 fractions per week. The evaluation of tumor response was determined by CT scans performed at 3 months after the cessation of RT, followed by the evaluation of toxicity by Common Terminology Criteria for Adverse Events version 3.0. The median follow-up period after radiotherapy was 18 months. Results: A complete response (CR) was achieved in 5 of 12 lesions (41.7%) at CT performed at 3 months after the cessation, whereas the overall complete response was observed in 7 of 12 cases (58.3%). In-field local control rate was sustained in 83.3% of patients. All patients developed intra-hepatic metastases except for 2 patients. The overall survival rate was 90.0% at 1 year and 67.5% at 2 years, respectively. Three patients developed Grade 1 nausea during RT and 1 patient showed a progression of ascites after RT. There was no grade 3 or greater treatment-related toxicities. Conclusion: Hypofractionated RT for small-sized HCC as a salvage therapy showed a 58.3% CR rate and 83.3% of local control. Fifty Gy administered in 10 fractions of partial liver irradiation is considered as a tolerable dose that does not cause severe complications.