• 한국의학물리학회지:의학물리
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• 제34권4호
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• pp.41-47
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• 2023

Purpose: This study aimed to dosimetrically compare the technique of three-dimensional conformal radiotherapy (3D CRT), which is a traditional prophylactic cranial irradiation method, and the intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques used in the last few decades with the dynamic conformal arc therapy (DCAT) technique. Methods: The 3D CRT, VMAT, IMRT, and DCAT plans were prepared with 25 Gy in 10 fractions in a Monaco planning system. The target volume and the critical organ doses were compared. A comparison of the body V₂, V₅, and V₁₀ doses, monitor unit (MU), and beam on-time values was also performed. Results: In planned target volume of the brain (PTV_Brain), the highest D99 dose value (P<0.001) and the most homogeneous (P=0.049) dose distribution according to the heterogeneity index were obtained using the VMAT technique. In contrast, the lowest values were obtained using the 3D CRT technique in the body V₂, V₅, and V₁₀ doses. The MU values were the lowest when DCAT (P=0.001) was used. These values were 0.34% (P=0.256) lower with the 3D CRT technique, 66% (P=0.001) lower with IMRT, and 72% (P=0.001) lower with VMAT. The beam on-time values were the lowest with the 3D CRT planning (P<0.001), 3.8% (P=0.008) lower than DCAT, 65% (P=0.001) lower than VMAT planning, and 76% (P=0.001) lower than IMRT planning. Conclusions: Without sacrificing the homogeneous dose distribution and the critical organ doses in IMRTs, three to four times less treatment time, less low-dose volume, less leakage radiation, and less radiation scattering could be achieved when the DCAT technique is used similar to conventional methods. In short, DCAT, which is applicable in small target volumes, can also be successfully planned in large target volumes, such as the whole-brain.

• Radiation Oncology Journal
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• 제2권2호
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• pp.221-228
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• 1984

The recogition that the vast majority of patients with small cell lung cancer have distant metastatic disease at the time of diagnosis lead to the use of systemic chemotherapy and consequent major improvement in survival, but recently evaulated treatment strategies, integration of large field chest irradiation with chemotherapy lead to the improved the local control and relapse free survival in limited SCLC. Therefore, it is logical to combine the two modalities in an effort to maximize the therapeutic effect. Authors performed the combination chemotherapy of CAV (Cyclophosphamide, Adriamycin, an6 Vincristine) and radiotherapy of primary tumor and regional lymphatics with prophylatic cranial irradiation in 42 patients of limited SCLC, from Mar. 1978 to Dec. 1982 Seoul National University Hospital. The results are as follows : 1. CR and PR after 2 cycles chemotherapy is $7\%$ and $43\%$, respectively however, subsequent response to radiotherapy is $38\%$ and $43\%$ in CR and PR. 2. Overall median survival peroid is 8.6 months. 3. 1 year and 2 years survival rate is $46.3\%$ and $20.5\%$, respectively. 4. Incidence of proven brain metastasis is $5\%$.

• Radiation Oncology Journal
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• 제34권4호
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• pp.313-321
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• 2016

Purpose: Total scalp irradiation (TSI) is a rare but challenging indication. We previously reported that non-coplanar intensity-modulated radiotherapy (IMRT) was superior to coplanar IMRT in organ-at-risk (OAR) protection and target dose distribution. This consecutive treatment planning study compared IMRT with volumetric-modulated arc therapy (VMAT). Materials and Methods: A retrospective treatment plan databank search was performed and 5 patient cases were randomly selected. Cranial imaging was restored from the initial planning computed tomography (CT) and target volumes and OAR were redelineated. For each patients, three treatment plans were calculated (coplanar/non-coplanar IMRT, VMAT; prescribed dose 50 Gy, single dose 2 Gy). Conformity, homogeneity and dose volume histograms were used for plan. Results: VMAT featured the lowest monitor units and the sharpest dose gradient (1.6 Gy/mm). Planning target volume (PTV) coverage and homogeneity was better in VMAT (coverage, 0.95; homogeneity index [HI], 0.118) compared to IMRT (coverage, 0.94; HI, 0.119) but coplanar IMRT produced the most conformal plans (conformity index [CI], 0.43). Minimum PTV dose range was 66.8%-88.4% in coplanar, 77.5%-88.2% in non-coplanar IMRT and 82.8%-90.3% in VMAT. Mean dose to the brain, brain stem, optic system (maximum dose) and lenses were 18.6, 13.2, 9.1, and 5.2 Gy for VMAT, 21.9, 13.4, 14.5, and 6.3 Gy for non-coplanar and 22.8, 16.5, 11.5, and 5.9 Gy for coplanar IMRT. Maximum optic chiasm dose was 7.7, 8.4, and 11.1 Gy (non-coplanar IMRT, VMAT, and coplanar IMRT). Conclusion: Target coverage, homogeneity and OAR protection, was slightly superior in VMAT plans which also produced the sharpest dose gradient towards healthy tissue.

• 한국임상수의학회지
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• 제40권2호
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• pp.104-112
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• 2023

The change in the position of the abdominal organs due to movement by respiration is one of the reasons behind inaccurate irradiation of organs during radiotherapy (RT). Although studies in human medicine have revealed on the respiratory movements of abdominal organs, there is little information and no reference data for dogs. The purpose of this study was to establish the reference values of abdominal organs movement in various postures using computed tomography (CT), and to compare the movements of organs between dorsal recumbency and ventral, right and left lateral recumbency during respiration. CT images for kidney, adrenal gland, medial iliac lymph node, urinary bladder, gallbladder, liver, stomach, and thoracic and lumbar vertebral body of five beagle dogs were acquired. The movements of organs were evaluated by comparing the end-expiratory and end-inspiratory images. Movements of the organs were evaluated by dividing it into right-to-left, dorsal-to-ventral, and cranial-to-caudal directions. The movements of abdominal organs according to the change in postures and respiration were establish. The movement of the bilateral organs was the least when the organs were in the downward position (p < 0.017). The movement of cranial-to-caudal direction was greater than the movement of the other directions in most of the organs. Data obtained in this study may be useful in selecting the appropriate posture that can reduce the movements of organs to be treated with RT, and the data could be useful for setting the planning target volume to consider the movements of the abdominal organs by respiration.

• Clinical and Experimental Pediatrics
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• 제46권6호
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• pp.566-571
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• 2003

목 적 : 백질뇌병증은 중추신경계 예방 요법을 시행하는 혈액종양 환자들에게는 심각한 합병증의 하나로, 이러한 백질뇌병증을 최소화하기 위해서는 조기 진단과 그에 따른 치료 방법의 변경이 중요하다 하겠다. 이 연구는 소아 혈액종양 환자에서 예방적 중추신경계 치료에 따른 백질뇌병증의 임상 양상 및 치료 방법 변경 후의 예후에 관해 조사하고, 백질뇌병증의 발생을 최소화하기 위한 정기적 두부 자기공명영상 촬영의 의의를 살펴보고자 시행되었다. 방 법 : 1995년 10월부터 2002년 5월까지 경북대학교병원 소아과에서 급성 림프구성 백혈병 및 B세포 림프종으로 진단받고 중추신경계 예방 치료 후 백질뇌병증이 발견된 16명의 환자를 대상으로 병력지와 MRI를 후향적으로 조사하였다. 결 과 : 급성 림프구성 백혈병 환자 15명과 B세포 림프종 환자 1명의 백질뇌병증 진단 시 연령은 중앙값 5년 3개월이었고, 남녀비는 3 : 1이었다. 항암치료 시작 후 백질뇌병증 진단까지 걸린 시간은 2개월에서 17개월이었다. 백질뇌병증 발생 전 투여한 척수강 내 MTX 투여 횟수는 2회에서 15회로 16명에서 모두 시행하였고, 두부 방사선 치료는 10명에서만 시행하였고 용량은 1,800 rads였다. 백질뇌병증 진단 전 경련, 성격 변화, 두통, 정신 이상, 구음 장애, 의식 변화 등의 정신신경학적 증상이 있었던 경우가 10명 있었으며 증상이 없었던 경우가 6명이었다. 백질뇌병증이 진단되었던 16명의 환자 중 4명은 사망하였으며 나머지 12명의 환아 중에서 현재 계속 항암치료 중인 경우가 8명, 항암치료를 종료한 환자가 3명, 그리고 보호자가 원하여 항암치료를 중지한 경우가 1명이었다. 백질뇌병증 진단 후 자기공명영상의 추적관찰을 시행한 경우가 12명, 시기상 아직 시행하지 못한 경우가 4명이었으며 추적관찰을 시행한 경우 중 자기공명영상에서 병변이 호전된 경우가 4명, 지속되는 경우가 6명, 악화된 경우가 2명이었다. 병변이 호전된 4명 중 2명은 병변이 거의 사라져 정상에 가까운 소견을 보였다. 결 론 : 중추신경계 예방 요법으로 사용하는 척수강 내 MTX 주입 요법과 두부 방사선 조사를 비롯하여 정맥으로 투여되는 MTX 또한 백질뇌병증을 유발하며, 이러한 백질뇌병증은 증상없이 발현되는 경우도 많아 병변의 조기발견을 위한 정기적인 자기공명영상의 촬영이 필요하며, 백질뇌병증의 발견 즉시 즉각적인 조치를 취하여 신경학적 기능의 회복을 가능하게 해야 할 것이라고 생각된다.

• Radiation Oncology Journal
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• 제14권2호
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• pp.137-147
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• 1996

목적 : 소아 급성임파모구성 백혈병 환자에 있어 예방적 전뇌방사선조사 및 척수강내화학 요법후 중추신경계 재발율, 재발양상, 중추신경계 무병생존율, 전체무병생존율및 이에 영향을 미치는 예후인자들을 알아보고자 하였다. 대상 및 방법 : 1987년 7원부터 1992년 6월까지 예방적 전뇌 방사선조사를 받은 급성 임파구성 백혈병 환아 90예를 대상으로 후향적 분석을 시행하였다. 3명을 제외한 모든 환자들이 일일 180 cGy 씩 퐁 1800 cGy의 전뇌방사선치료를 받았고, 방사선 치료중 척수강내 화학요법이 병행되었다. 결과 : 추적관착기간 36-96 개원 (중앙값 60 개원)동안 90명의 환아중 9례에서 중추신경계 재발을 보였으나, 골수재발이 선행되었던 3례를 제외하면 중추신경계 재발율은 $6.7\%$로 나타났다. 중추신경계 재발환자의 $89\%$에서 골수재발이 동반되었으며, $11\%$에서 고환재발이 동반되었다. 골수완전관해로부터 중추신경계 재발까지의 경과기간은 16개월 (중앙값) 이었고, $78\%$의 중추신경계 재발이 관해유지요법중에 발생하였다. 2년 및 5년 중추신경계 무병생존율은 각각 $68\%$, $42\%$였고, 중앙값은 43 개월이었다. 중추신경계 무병생존율에 영향을 미치는 예후인자는 진단당시의 백혈구수 (5만 기준), FAB 분류군, CALGB 위험분류기준으로 나타났다. 2년 및 5년 전체무병생존율은 각각 $61\%$, $39\%$였고 중앙값은 34 개월이었다. 전체무병생존율에 영향을 미치는 예후인자는 진단당시의 백혈구수 (5만 기준), FAB 분류군, CALGB 및 POG 위험분류군으로 나타났다. 결론 : 본 연구에서 중추신경계 재발율은 $6.7\%$, 로 다른 연구들에서 보고하는 범위에 속하여 효과적인 중추신경계 예방요법으로 판단 되었다. 진단당시의 나이및 백혈구수를 기준으로한 위험분류기준 중 POG 및 CALGB 위험분류기준이 중추신경계 무병생존율 및 전체무병생존율에 유의한 예후인자로 나타났다. 부작용을 최소화하면서도 효과적인 중추신경계예방요법을 알아내기 위해서는 각 위험분류군에 따른 중추신경계 예방요법의 차별화에 대한 전향적인 연구및장기 생존자들에 대한 체계적인 신경 심리학적 추적 조사가 필요할 것으로 사료된다.

• Journal of Korean Neurosurgical Society
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• 제30권3호
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• pp.334-341
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• 2001

Objective : We have currently changed treatment strategies to methotrexate(MTX)-based preirradiation chemotherapy with subsequent planned radiation for the initial therapy of primary central nervous system lymphoma (PCNSL). The aim of this study was to evaluate the results of treating PCNSL with chemotherapy plus radiotherapy (CRT) or radiotherapy(RT) alone. Method and Material : This study involved 10 females and 3 males patients with a mean age of 54.2 years. All patients underwent surgery, open(8 cases) or stereotactic biopsy(5 cases) for histological diagnosis. Eleven tumors were diffuse large B-cell lymphomas. Tumor volume change in the follow-up images and survival time were evaluated in patients treated with CRT and RT alone. In the beginning, two patients received ProMACE-Cytabom chemotherapeutic regimen, but did not complete the course and died of progressive tumor 8 and 9 months after diagnosis, respectively. One patient died at 6 months before chemotherapy. These three were excluded from the survival analysis. Five patients(RT group) completed full courses of cranial irradiation with or without boost. For the current combined modality treatment, high-dose MTXbased chemotherapy(systemic and intrathecal MTX, IV vincristine, and oral procarbazine) followed by whole brain irrdiation to 45Gy to tumor was introduced in 5 patients of CRT group. Result : A complete response was achieved in three of five who received RT only and in all of five who received CRT. All patients in CRT groups are in disease free status at a mean 23 months following therapy. The RT group patients refused any additional salvage therapy at tumor relapse and survived at mean 20 months from diagnosis. The Karnofsky performance status improved in eight of ten patients with treatment. The treatment toxicity included leukoencephalopathy in RT group and severe leukopenia, transient hepatitis, avascular necrosis of femoral head, hearing loss, and amenorrhea in CRT group, respectively. Conclusion : The combined modality therapy of MTX-based chemotherapy plus radiotherapy for PCNSL may enhance tumor response and improve patient survival. The patients who received CRT should be carefully followed up because of the higher risk of treatment-induced late neurotoxicity.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6263-6267
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• 2014

Background: It is standard treatment to combine chemotherapy (CT) and thoracic radiotherapy (TRT) in treating patients with limited stage small cell lung cancer (LS-SCLC). However, optimal timing of TRT is unclear. We here evaluated the survival impact of early versus late TRT in patients with LS-SCLC. Materials and Methods: Follow-up was retrospectively analyzed for seventy consecutive LS-SCLC patients who had successfully completed chemo-TRT between January 2006 and January 2012. Patients received TRT after either 1 to 2 cycles of CT (early TRT) or after 3 to 6 cycles of CT (late TRT). Survival and response rates were evaluated using the Kaplan-Meier method and comparisons were made using the multivariate Cox regression test. Results: Median follow-up was 24 (5 to 57) months. Carboplatin+etoposide was the most frequent induction CT (59%). Median overall, disease free, and metastasis free survivals in all patients were 15 (5 to 57), 5 (0 to 48) and 11 (3 to 57) months respectively. Late TRT was superior to early TRT group in terms of response rate (p=0.05). 3 year overall survival (OS) rates in late versus early TRT groups were 31% versus 17%, respectively (p=0.03). Early TRT (p=0.03), and incomplete response to TRT (p=0.004) were negative predictors of OS. Significant positive prognostic factors for distant metastasis free survival were late TRT (p=0.03), and use of PCI (p=0.01). Use of carboplatin versus cisplatin for induction CT had no significant impact on OS (p=0.634), DFS (p=0.727), and MFS (p=0.309). Conclusions: Late TRT appeared to be superior to early TRT in LS-SCLC treatment in terms of complete response, OS and DMFS. Carboplatin or cisplatin can be combined with etoposide in the induction CT owing to similar survival outcomes.

• Tuberculosis and Respiratory Diseases
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• 제63권2호
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• pp.154-164
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• 2007

배경: Irinotecan hydrochloride는 topoisomerase I inhibitor로서 소세포 폐암에 효과적인 약제로 알려져 있다. Irinotecan은 cisplatin과 더불어 방사선감작물질로 작용하기도 한다. 본 연구는 이전에 치료받은 경험이 없는 제한성 병기의 소세포 폐암 환자에서 irinotecan과 cisplatin(IP)의 방사선 동시화학요법의 효과를 평가하기 위하여 시행되었다. 방법: 2002년 12월부터 2004년 11월까지 충남대학교 병원에서 새로이 제한성 병기의 소세포 폐암으로 진단된 24명의 환자들을 대상으로 하였다. Irinotecan $60mg/m^2$을 제 1일과 제 8일째 투여하였고 cisplatin $60mg/m^2$을 제 1일째 투여하였으며 매 3주 간격으로 시행되었다. 제 3차 항암화학요법을 시작하는 날과 동시에 과다 분할방사선 치료(twice-daily thoracic irradiation; 45 Gy total)을 시작하였다. 예방적 전 뇌 방사선 조사(Prophylactic cranial irradiation)가 방사선 동시화학요법이 끝난 후 완전반응(complete response)을 나타낸 환자에서 시행되었다. 제 2차 항암요법과 제 6차 항암요법이 끝난 후에 흉부 전산화 단층촬영과 기관지경 등을 통한 병기의 재평가가 이루어졌다. 결과: 병기의 재평가는 19명의 환자에게 이루어졌다. 중앙 추적관찰기간은 12.5개월이고 전체 99회의 항암치료가 시행되었다. 평균 한 환자당 5.2회의 항암치료가 시행되었다. 실제 용량강도는 cisplatin $19.6mg/m^2$/week과 irinotecan $38.2mg/m^2$/week이었다. 9명의 환자가 완전반응을 보였고 10명의 환자가 부분반응(partial response)을 보여서 전체 반응률은 95%였다. 3에서 4도의 혈액학적 독성은 백혈구 감소증(35% of cycles), 빈혈(7% of cycles), 혈소판 감소증(7% of cycles) 등으로 나타났다. 3에서 4도의 비 혈액학적 독성은 설사(5% of cycles)였다. 3에서 4도의 방사선 식도염(10% of patients)을 제외하고는 과다 분할 방사선 치료를 이용한 방사선 동시 화학요법의 기존의 방법과 독성 면에서는 큰 차이가 없었다. 치료와 관련된 사망은 관찰되지 않았다. 평가가 가능한 환자들에서 1년 생존율과 2년 생존율은 각각 89% (16/18)와 47% (9/18)였다. 결론: 3주 간격으로 시행된 irinotecan과 cisplatin을 이용한 과다분할 방사선 동시 요법은 제한성 병기의 소세포 폐암 환자에서 부작용은 높지 않으면서 효과적인 치료법으로 고려될 수 있을 것이다.

• Journal of Korean Neurosurgical Society
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• 제50권6호
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• pp.535-537
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• 2011

Recently, combination of surgery and radiation therapy (RT) has been recommended in the treatment of craniopharyngioma. RT could be associated with late complications, including vasculopathy. We report two cases of the moyamoya syndrome seen in children with craniopharyngioma who received RT after surgical resection. Thirty-five patients in pediatric age with craniopharyngioma were surgically treated. Fifteen out of 35 patients underwent surgical resection followed by RT or gamma knife surgery. Two of the 15 were found to have symptoms of transient ischemic attack and were diagnosed as moyamoya syndrome through the cerebral angiography. Age at RT was 4 and 13 years, respectively. The latent period for development of the moyamoya syndrome was 27 months and 3 years, respectively, after RT. The RT dose of both patients was 54 Gy. These two patients received bilateral encephaloduroarteriosynangiosis procedures. We report here these two cases of radiation-induced moyamoya syndrome in pediatric craniopharyngioma. Pediatric patients with craniopharyngioma who received RT should be reminded, during follow-up, about the risk of development of the moyamoya syndrome.