Treatment Margin Assessment using Mega-Voltage Computed Tomography of a Tomotherapy Unit in the Radiotherapy of a Liver Tumor

Sei Hwan You(유세환),Jinsil Seong(성진실),Ik Jae Lee(이익재),Woong Sub Koom(금웅섭),Byeong Chul Jeon(전병철) 대한방사선종양학회 2008 Radiation Oncology Journal Vol.26 No.4

목 적: 토모테라피 영상유도장치인 MVCT (mega-voltage computed tomography) 영상을 이용하여 자유 호흡시 분할 치료 간 간조직의 위치변화 양상을 알아보고자 하였다. 대상 및 방법: 2006년 4월부터 2007년 8월까지 간종양에 토모테라피를 받은 환자 26 명을 대상으로 치료 시작 후 10 회까지 매회 치료시의 MVCT 영상을 분석하였다. 1차적으로 골격 구조에 따라 셋업오차보정을 한 상태에서 2차원 직교좌표계 상에서 간조직 경계부위의 위치 변화를 치료계획 KVCT (Kilo-Voltage Computed Tomography)와 MVCT의 영상융합을 통해 비교하여 오차 정도를 파악하였다. 간종양의 위치 별 변화 양상을 보기 위하여 종양 위치를 Couinaud’s proposal을 기준으로 1군(Segment 1), 2군(Segment 2, 3, 4), 3군(Segment 5, 6), 4군(Segment 7, 8)으로 나누어 각 군별 위치 변화 양상을 비교하였다. 결 과: MVCT를 통해 알아본 평균 셋업오차는 각각 0.45±2.04 mm (좌-우), 0.97±4.06 mm (상-하), 8.38±4.67 mm (전-후) 이었다. 2군에서 전방 바깥쪽으로 2.80±1.73 mm, 좌방 안쪽으로 2.23±1.37 mm 이동하였고 4군에서는 전,후, 좌, 우 각 방향으로 −0.15±3.93 mm, −3.15±6.58 mm, −0.60±3.58 mm, −4.50±5.35 mm 이동하였다. 1, 2, 3군에서 후방으로의 위치 변화는 평균 1 mm 이내였다(각각 0.07±0.99 mm, −0.07±1.38 mm, 0.50±0.47 mm). MVCT 값들의 적용 시 보이는 2군에서의 종양체적 감소는 위 독성을 증가시킬 것으로 생각되었다. 결 론: 분할치료 간 간조직의 위치 변화 양상은 각 군마다 편차가 있는 가운데 어느 정도 규칙적이었다. 호흡에 의한 간조직의 기하학적 변형은 segment 2, 3, 4에서 좌방 표적 체적의 감소를 가져오는 반면 segment 5, 6에서는 호흡에 도 불구하고 안정적인 양상을 나타내었다. 따라서 자유 호흡 상태에서 간 좌엽에 대한 방사선치료 시 위에 대한 독성을 줄이기 위해 보다 세심한 접근이 필요하다. Purpose: To identify the inter-fractional shift pattern and to assess an adequate treatment margin in the radiotherapy of a liver tumor using mega-voltage computed tomography (MVCT) of a tomotherapy unit. Materials and Methods: Twenty-six patients were treated for liver tumors by tomotherapy from April 2006 to August 2007. The MVCT images of each patient were analyzed from the 1st to the 10th fraction for the assessment of the daily liver shift by four groups based on Couinard’s proposal. Daily setup errors were corrected by bony landmarks as a prerequisite. Subsequently, the anterior-, posterior-, right-, and left shifts of the liver edges were measured by maximum linear discrepancies between the kilo-voltage computed tomography (KVCT) image and MVCT image. All data were set in the 2-dimensional right angle coordinate system of the transverse section of each patient’s body. Results: The liver boundary shift had different patterns for each group. In group II (segment 2, 3, and 4), the anterior mean shift was 2.80±1.73 mm outwards, while the left mean shift was 2.23±1.37 mm inwards. In group IV (segment 7 and 8), the anterior-, posterior-, right-, and left mean shifts were 0.15±3.93 mm inwards, 3.15±6.58 mm inwards, 0.60±3.58 mm inwards, and 4.50±5.35 mm inwards, respectively. The reduced volume in group II after MVCT reassessment might be a consequence of stomach toxicity. Conclusion: Inter-fractional liver shifts of each group based on Couinard’s proposal were somewhat systematic despite certain variations observed in each patient. The geometrical deformation of the liver by respiratory movement can cause shrinkage in the left margins of liver. We recommend a more sophisticated approach in free-breathing mode when irradiating the left lobe of liver in order to avoid stomach toxicity.

Pancreatic radiation effect in apoptosis-related rectal radiation toxicity

You, Sei Hwan,Cho, Mee Yon,Sohn, Joon Hyung,Lee, Chang Geol JAPAN RADIATION RESEACH SOCIETY 2018 JOURNAL OF RADIATION RESEARCH Vol.59 No.5

<P><B>Abstract</B></P><P>Pancreatic radiation effect (PRE) can be a component of gastrointestinal tract (GIT) radiotoxicity. This inter-organ correlation between the GIT and the pancreas was assessed through a rat model. Separate local irradiation to the abdomen and the pelvis was applied concurrently for 8-week-old male Sprague Dawley rats. Abdominal irradiation was categorized into pancreatic shield (PS) and non-pancreatic shield (NPS) irradiation. After 5 Gy and 15 Gy irradiation, the rectal mucosa was analyzed at the first week (early phase, Ep) and the 14th week (late phase, Lp). A slow gain in body weight was observed initially, particularly in the NPS group receiving a 15 Gy dose (<I>P</I> < 0.001). The large number of apoptotic bodies after 15 Gy at Ep decreased at Lp. At Ep for the 5-Gy group, the NPS group revealed more fibrotic change than the PS group (<I>P</I> = 0.002). Cleaved caspase-3 (CCP3) expression was greater at Lp, and the Ep–Lp increase was prominent in the NPS-15-Gy group (<I>P</I> = 0.010). At Lp, for 15 Gy irradiation, CCP3 was expressed more in the NPS group than in the PS group (<I>P</I> = 0.032). Despite no direct toxicity difference between the PS and NPS groups, small changes in parameters such as fibrosis or CCP3 expression suggest that pancreatic shielding does have an effect on the radiation response in the rectal mucosa, which suggests a need for a multi-organ effect-based approach in GIT radiotoxicity assessment.</P>

항문암의 방사선치료 시 방사선 조사 기법에 따른 회음부 피부 독성

유세환(Sei Hwan You),성진실(Jinsil Seong),금웅섭(Woong Sub Koom) 대한방사선종양학회 2008 Radiation Oncology Journal Vol.26 No.4

목 적: 항문암의 방사선치료는 급성부작용을 많이 동반하므로 다양한 치료 기법이 적용되어왔다. 본원에서 시행된 항문암 방사선치료를 회음부 피부반응의 측면에서 검토하여 최적의 방사선치료 기법을 모색하고자 하였다. 대상 및 방법: 1990년부터 2007년까지 항문암으로 근치적 항암화학방사선치료를 마친 환자 35명을 대상으로 방 사선 조사 방법 및 관련된 임상적 자료들을 이용하였다. 방사선치료는 원발병소, 영역림프절 및 서혜부림프절이 치료범위에 포함된 상태로 1.8 Gy 씩 41.4∼45 Gy 조사 후 원발 병소 또는 전이성 림프절에 추가 조사하는 것을 원칙으로 하였다. 방사선 조사 기법은 조사 부위 및 조사 수에 따라 4가지로 분류하였으며 각 기법에 따른 회음부 급성피부반응 및 치료중지기간 간의 관련 여부를 알아보았다. 결 과: 방사선치료 중 28명(80.0%)의 환자에서 2등급 이상의 방사선 피부염이 발생하였고 10명(28.6%)이 3등급 이상의 방사선 피부염을 보였다. 4가지 방사선 조사 기법 중 원발병소와 영역림프절에 대한 3면 X-선 및 양측 서혜부림프절에 대한 전자선 조사 군과 electron thunderbird 군에서 방사선 피부염이 동반된 환자 수가 상대적으로 적었으며 치료중지기간이 각각 8.2±10.2일, 5.7±5.7일로써 다른 치료 기법보다 적었다. 방사선치료 종료 후 1개월 시점에서 27명(77.1%)의 환자에서 완전 관해를 보였으며 5년 생존율은 67.7%이었다. 결 론: 항문암의 방사선치료에 있어 방사선 조사 방법 및 범위가 치료순응도에 영향을 미칠 수 있으며, X-선의 회 음부 조사 범위를 줄이는 방법이 회음부의 심각한 방사선 피부염을 감소시킴으로써 환자의 치료순응도를 높이는데 있어 적절할 것으로 생각된다. Purpose: Various treatment techniques have been attempted for the radiotherapy of anal cancer because of acute side effects such as perineal skin reactions. This study was performed to investigate an optimal radiotherapy technique in anal cancer. Materials and Methods: The study subjects included 35 patients who underwent definitive concurrent chemoradiotherapy for anal cancer in Yonsei Cancer Center between 1990 and 2007. The patients’ clinical data, including irradiation technique, were reviewed retrospectively. The primary lesion, regional lymph nodes, and both inguinal lymph nodes were irradiated by 41.4∼45 Gy with a conventional schedule, followed by a boost does to the primary lesion or metastatic lymph nodes. The radiotherapy technique was classified into four categories according to the irradiation field and number of portals. In turn, acute skin reactions associated with the treatment interruption period were investigated according to each of the four techniques. Results: 28 patients (80.0%) had grade 2 radiation dermatitis or greater, whereas 10 patients (28.6%) had grade 3 radiation dermatitis or greater during radiotherapy. Radiation dermatitis and the treatment interruption period were relatively lower in patients belonging to the posterior-right-left 3 x-ray field with inguinal electron boost and in patients belonging to electron thunderbird techniques. The interruption periods were 8.2±10.2 and 5.7±7.7 for the two technique groups, respectively. Twenty-seven patients (77.1%) went into complete remission at 1 month after radiotherapy and the overall 5 year survival rates were 67.7%. Conclusion: Field size and beam arrangement can affect patients' compliance in anal cancer radiotherapy, whereas a small x-ray field for the perineum seems to be helpful by decreasing severe radiation dermatitis.

Sphingosine 1-Phosphate and Sphingosine Kinase Activity during chicken Embryonic Development

Chang Hwan Choi,Ji Seon Jeong,Bo Im Yoo,You Xun Jin,Dong Cheul Moon,Hwan Soo Yoo,Sei Kwan Oh,Seon Pyo Hong,Yong Moon Lee 경희대학교 동서약학연구소 2008 경희약대 논문집 Vol.35 No.1

한국인 인슐린의존형 당뇨병 환자의 HLA-DR/DQ 유전자형과 소도특이 자가항체의 연관성

안유헌,김진배,신진호,김목현,박용수,최웅환,양세원,김태화,황승덕,이희발 대한당뇨병학회 1997 Diabetes and Metabolism Journal Vol.21 No.3

Assessment of inter- and intra-fractional volume of bladder and body contour by mega-voltage computed tomography in helical tomotherapy for pelvic malignancy

Kim, Sunghyun,You, Sei Hwan,Eum, Young Ju The Korean Society for Radiation Oncology 2018 Radiation Oncology Journal Vol.36 No.3

Purpose: We describe the daily bladder volume change observed by mega-voltage computed tomography (MVCT) during pelvic radiotherapy with potential predictors of increased bladder volume variations. Materials and Methods: For 41 patients who received pelvic area irradiation, the volumes of bladder and pelvic body contour were measured twice a day with pre- and post-irradiation MVCT from the 1st to the 10th fraction. The median prescription dose was 20 Gy (range, 18 to 30 Gy) up to a 10th fraction. The upper and lower margin of MVCT scanning was consistent during the daily treatments. The median age was 69 years (range, 33 to 86 years) and 10 patients (24.4%) were treated postoperatively. Results: Overall bladder volume on planning computed tomography was 139.7 ± 92.8 mL. Generally, post-irradiation bladder volume (POSTBV) was larger than pre-irradiation bladder volume (PREBV) (p < 0.001). The mean PREBV and POSTBV was reduced after 10 fraction treatments by 21.3% (p = 0.028) and 25.4% (p = 0.007), respectively. The MVCT-scanned body contour volumes had a tendency to decrease as the treatment sessions progressed (p = 0.043 at the 8th fraction and p = 0.044 at the 10th fraction). There was a statistically significant correlation between bladder filling time and PREBV (p = 0.001). Conclusion: Daily MVCT-based bladder volume assessment was feasible both intra- and inter-fractionally.

Assessment of inter- and intra-fractional volume of bladder and body contour by mega-voltage computed tomography in helical tomotherapy for pelvic malignancy

Sunghyun Kim,Sei Hwan You,Young Ju Eum 대한방사선종양학회 2018 Radiation Oncology Journal Vol.36 No.3

Purpose: We describe the daily bladder volume change observed by mega-voltage computed tomography (MVCT) during pelvic radiotherapy with potential predictors of increased bladder volume variations. Materials and Methods: For 41 patients who received pelvic area irradiation, the volumes of bladder and pelvic body contour were measured twice a day with pre- and post-irradiation MVCT from the 1st to the 10th fraction. The median prescription dose was 20 Gy (range, 18 to 30 Gy) up to a 10th fraction. The upper and lower margin of MVCT scanning was consistent during the daily treatments. The median age was 69 years (range, 33 to 86 years) and 10 patients (24.4%) were treated postoperatively. Results: Overall bladder volume on planning computed tomography was 139.7 ± 92.8 mL. Generally, post-irradiation bladder volume (POSTBV) was larger than pre-irradiation bladder volume (PREBV) (p < 0.001). The mean PREBV and POSTBV was reduced after 10 fraction treatments by 21.3% (p = 0.028) and 25.4% (p = 0.007), respectively. The MVCT-scanned body contour volumes had a tendency to decrease as the treatment sessions progressed (p = 0.043 at the 8th fraction and p = 0.044 at the 10th fraction). There was a statistically significant correlation between bladder filling time and PREBV (p = 0.001). Conclusion: Daily MVCT-based bladder volume assessment was feasible both intra- and inter-fractionally.

Ginsenoside compound-Mc1 attenuates oxidative stress and apoptosis in cardiomyocytes through an AMP-activated protein kinase-dependent mechanism

Hong, So-hyeon,Hwang, Hwan-Jin,Kim, Joo Won,Kim, Jung A.,Lee, You Bin,Roh, Eun,Choi, Kyung Mook,Baik, Sei Hyun,Yoo, Hye Jin The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.4

Background: Ginsenoside compound-Mc1 (Mc1) is a member of the deglycosylated ginsenosides obtained from ginseng extract. Although several ginsenosides have a cardioprotective effect, this has not been demonstrated in ginsenoside Mc1. Methods: We treated H9c2 cells with hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>) and ginsenoside Mc1 to evaluate the antioxidant effects of Mc1. The levels of antioxidant molecules, catalase, and superoxide dismutase 2 (SOD2) were measured, and cell viability was determined using the Bcl2-associated X protein (Bax):B-cell lymphoma-extra large ratio, a cytotoxicity assay, and flow cytometry. We generated mice with high-fat diet (HFD)-induced obesity using ginsenoside Mc1 and assessed their heart tissues to evaluate the antioxidant effect and the fibrosis-reducing capability of ginsenoside Mc1. Results: Ginsenoside Mc1 significantly increased the level of phosphorylated AMP-activated protein kinase (AMPK) in the H9c2 cells. The expression levels of catalase and SOD2 increased significantly after treatment with ginsenoside Mc1, resulting in a decrease in the production of H<SUB>2</SUB>O<SUB>2</SUB>-mediated reactive oxygen species. Treatment with ginsenoside Mc1 also significantly reduced the H<SUB>2</SUB>O<SUB>2</SUB>-mediated elevation of the Bax:Bcl2 ratio and the number of DNA-damaged cells, which was significantly attenuated by treatment with an AMPK inhibitor. Consistent with the in vitro data, ginsenoside Mc1 upregulated the levels of catalase and SOD2 and decreased the Bax:B-cell lymphoma-extra large ratio and caspase-3 activity in the heart tissues of HFD-induced obese mice, resulting in reduced collagen deposition. Conclusion: Ginsenoside Mc1 decreases oxidative stress and increases cell viability in H9c2 cells and the heart tissue isolated from HFD-fed mice via an AMPK-dependent mechanism, suggesting its potential as a novel therapeutic agent for oxidative stress-related cardiac diseases.

Superficial Dosimetry for Helical Tomotherapy

Song Yih Kim(김송이),Sei Hwan You(유세환),Taesoo Song(송태수),Yong Nam Kim(김용남),Ki Chang Keum(금기창),Jae Ho Cho(조재호),Chang Geol Lee(이창걸),Jinsil Seong(성진실) 대한방사선종양학회 2009 Radiation Oncology Journal Vol.27 No.2

목 적: 피부와 같이 표면이 넓고 굴곡이 있는 부분을 치료할 때 토모테라피의 유용성과 치료 계획에서 계산된 표면 조사량의 정확성을 알아보고자 하였다. 대상 및 방법: 실린더 모양의 치즈 팬텀을 이용하여 2가지의 치료 계획을 세웠다. 첫 번째 계획은 표면에서 1 cm 깊이까지 고리 모양의 치료 부위를 설정하고, 여기에 2 Gy의 선량을 처방하였다. 다른 계획은 표면에서 5 mm 바깥쪽부터 1 cm 깊이까지 고리 모양의 치료 부위를 설정하고, 여기에 2 Gy의 선량을 처방하였다. 표면에서 2 cm 밑의 안쪽 부분은 차폐하여 방사선이 직접 들어가지 않도록 하였다. 표면 선량과 깊이에 따른 선량 분포를 측정하기 위하여, EDR2 필름을 팬텀 안에 넣었으며, TLD 칩 6개를 표면에 부착하였다. 결 과: 필름을 분석한 결과, 표면 선량은 첫 번째 계획에서 118.7 cGy였고 두 번째 계획에서 130.9 cGy였다. TLD칩을 분석한 결과, 필름에 비하여 표면 선량이 높게 나왔는데 이것은 TLD 칩의 두께로 인한 것으로 생각된다. 처방 선량의 95%에 다다르는 깊이는 첫 번째 계획의 경우 2.1 mm, 두 번째 계획의 경우 2.2 mm였다. 최대 선량은 처방 선량의 110%였다. 표면에서 깊어질수록, 선량은 빠르게 감소하였고, 표면에서 2 cm 깊이에서는 처방 선량의 20%만 측정되었다. 결 론: 토모테라피는 피부와 같은 넓고 굴곡진 부위를 치료하는데 유용하다. 하지만 표면에서 2 mm 깊이 이내의 경우 실제 선량이 계획된 선량보다 적게 나타나기 때문에, 이 깊이보다 얕게 위치한 부위를 치료할 경우에는 보상체가 필요하다. Purpose: To investigate the feasibility of helical tomotherapy on a wide curved area of the skin, and its accuracy in calculating the absorbed dose in the superficial region. Materials and Methods: Two types of treatment plans were made with the cylinder-shaped ‘cheese phantom’. In the first trial, 2 Gy was prescribed to a 1-cm depth from the surface. For the other trial, 2 Gy was prescribed to a 1-cm depth from the external side of the surface by 5 mm. The inner part of the phantom was completely blocked. To measure the surface dose and the depth dose profile, an EDR2 film was inserted into the phantom, while 6 TLD chips were attached to the surface. Results: The film indicated that the surface dose of the former case was 118.7 cGy and the latter case was 130.9 cGy. The TLD chips indicated that the surface dose was higher than these, but it was due to the finite thickness of the TLD chips. In the former case, 95% of the prescribed dose was obtained at a 2.1 mm depth, while the prescribed does was at 2.2 mm in the latter case. The maximum dose was about 110% of the prescribed dose. As the depth became deeper, the dose decreased rapidly. Accordingly, at a 2-cm depth, the dose was 20 % of the prescribed dose. Conclusion: Helical tomotherapy could be a useful application in the treatment of a wide area of the skin with curvature. However, for depths up to 2 mm, the planning system overestimated the superficial dose. For shallower targets, the use of a compensator such as a bolus is required.

Influence of different boost techniques on radiation dose to the left anterior descending coronary artery

Kawngwoo Park,Yongha Lee,Jihye Cha,Sei Hwan You,Sunghyun Kim,Jong Young Lee 대한방사선종양학회 2015 Radiation Oncology Journal Vol.33 No.3

Purpose: The purpose of this study is to compare the dosimetry of electron beam (EB) plans and three-dimensional helical tomotherapy (3DHT) plans for the patients with left-sided breast cancer, who underwent breast conserving surgery. Materials and Methods: We selected total of 15 patients based on the location of tumor, as following subsite: subareolar, upper outer, upper inner, lower lateral, and lower medial quadrants. The clinical target volume (CTV) was defined as the area of architectural distortion surrounded by surgical clip plus 1 cm margin. The conformity index (CI), homogeneity index (HI), quality of coverage (QC) and dose-volume parameters for the CTV, and organ at risk (OAR) were calculated. The following treatment techniques were assessed: single conformal EB plans; 3DHT plans with directional block of left anterior descending artery (LAD); and 3DHT plans with complete block of LAD. Results: 3DHT plans, regardless of type of LAD block, showed significantly better CI, HI, and QC for the CTVs, compared with the EB plans. However, 3DHT plans showed increase in the V1Gy at skin, left lung, and left breast. In terms of LAD, 3DHT plans with complete block of LAD showed extremely low dose, while dose increase in other OARs were observed, when compared with other plans. EB plans showed the worst conformity at upper outer quadrants of tumor bed site. Conclusion: 3DHT plans offer more favorable dose distributions to LAD, as well as improved target coverage in comparison with EB plans.