Journal of Yeungnam Medical Science

Sang Mo Yun

5 Articles

Role of Radiation Therapy in Treatment of Stomach Cancers: Sang Mo Yun, Myung Se Kim; Yeungnam Univ J Med. 2007;24(2 Suppl):S245-251. Published online December 31, 2007; DOI: https://doi.org/10.12701/yujm.2007.24.2S.S245

1,189 View
3 Download

Abstract PDF: Although occasionally used as a therapeutic modality, radiotherapy was not a routine part of the treatment of stomach cancer. As a single modality, preoperative radiotherapy showed some benefit, but this was not confirmed in radomized trial. In recent neoadjuvant trials, radiotherapy is usually given concurrently with chemotherapy, and pathologic complete response rates was about 30%. There were small studies of radiotherapy as an adjuvant, either alone or with chemotherapy, but the randomized studies using postoperative radiotherapy alone did not show a survival benefit. The results of intergroup gastric adjuvant trial(INT 0116) were presented in May 2000 at American Society of Clinical Oncology. In that report, postoperative concurrent chemoradiotherapy showed survival benefit. INT 0116 has established postoperative chemoradiotherapy as the standard care for high risk patients with resected stomach cancer. But, INT 0116 had several weak points including lack of standardized nodal dissection and delivery rates of treatments. So, Asian and European investigators did not agree. Korean study showed benefit of postoperative chemoradiotherapy after D2 dissection, but this study was not randomized. Recently, Korean investigators started randomized trial of chemoradiotherapy in D2 dissected patients. This trial may give answer to us about the benefit of postoperative chemoradiotherapy in resected stomach cancer.

Comparision of Parotid Gland Dose Distribution between 3DCRT and IMRT in Head and Neck Radiation Therapy: Sang Mo Yun, Sung Kyu Kim; Yeungnam Univ J Med. 2007;24(2 Suppl):S443-448. Published online December 31, 2007; DOI: https://doi.org/10.12701/yujm.2007.24.2S.S443

1,076 View
3 Download

Abstract PDF: Purpose：This study compared 3 dimensional conformal radiation therapy (3DCRT) to intensity modulated radiation therapy (IMRT) in parotid glands sparing in head and neck cancers. Materials and Methods：Planning target volume (PTV) was outlined on each CT slice. The dose of 50.4 Gy was prescribed to the PTV with the conventional fraction, 5 fractions per week. We also outlined spinal cord and both parotid glands. With Eclipse 3 dimensional planning system, 3DCRT and IMRT planning were done.
Results
：After plan optimization, PTV dose distribution was evaluated with dose volume histogram. The 90% isodose curve covered almost all of PTV for both techniques. Maximum and median dose for spinal cord were 36.8 Gy and 34.2 Gy in 3DCRT, 39.9 GY and 37.5 Gy in IMRT. For parotid glands, mean and median dose were 33.6 Gy and 37.6 Gy in 3DCRT, 24.9 Gy and 24.5 Gy in IMRT.
Conclusion
：For the non-pharyngeal head and neck cancers, 3DCRT was cost effective radiation modality in prevention radiation therapy induced xerostomia.

Dose distribution of Intensity Modulated Radiation Therapy and 3 Dimensional Conformal Radiation Therapy in Prostate Cancer: Sung Kyu Kim, Myung Se Kim, Sang Mo Yun; Yeungnam Univ J Med. 2007;24(2 Suppl):S538-543. Published online December 31, 2007; DOI: https://doi.org/10.12701/yujm.2007.24.2S.S538

1,205 View
3 Download
2 Crossref

Abstract PDF

Purpose：The aim of this study was to compare the dose distribution of intensity modulated radiation therapy (IMRT) with 3 dimensional conformal radiation therapy (3DCRT) in prostate cancer. Materials and Methods：The IMRT plan and the 3DCRT plan used the 9 fields technique, respectively. In IMRT, tumor dose was a total dose of 50 Gy at 2.0 Gy per day, 5 days a week for 5 weeks. All cases were following the dose volume histogram (DVH) constraints. The maximum and minimum tumor dose constraints were 5,075 cGy and 4,925 cGy, respectively. The rectum dose constraints were <35% over 40 Gy. The bladder dose constraints were <35% over 30 Gy. The femur head dose constraints were <15% over 16 Gy. Tumor dose in the 3DCRT were 50 Gy.
Results
：In IMRT, the maximum dose of PTV was 101.9% and minimum dose was 89.5% for given dose. In 3DCRT, the maximum dose of PTV was 103.5% and minimum dose was 86.5% for given dose. The rectum dose was 29.2% over 40 Gy in IMRT compared with 67.9% in 3DCRT. The bladder dose was 30.1% over 30 Gy in IMRT compared with 30.6% in 3DCRT. The right femur head dose was 5.3% over 16 Gy in IMRT compared with 8.3% in 3DCRT. The left femur head dose was 6.8% over 16 Gy in IMRT compared with 9.1% in 3 DCRT.
Conclusion
：The dose of critical organs (rectum, bladder, and femur head) in IMRT showed to reduce than dose of 3DCRT. The rectum dose over 40 Gy in IMRT was reduced 38.7% than 3DCRT. The bladder dose over 30 Gy in IMRT was similar to 3DCRT. The femur head dose over 16 Gy in IMRT was reduced about 2.3∼3% than 3DCRT.

Citations

Citations to this article as recorded by

Changes in Volume Dose by Treatment Plan According to pCT and CBCT in Image-guided Radiation Therapy for Prostate Cancer
Young Jin Won, Jung Hoon Kim
Journal of Radiological Science and Technology.2018; 41(3): 209. CrossRef
A Comparison between Three Dimensional Radiation Therapy and Intensity Modulated Tadiation Yherapy on Prostate Cancer
YoungJae Kim, JaeSub Lee, Seongill Hong, HyeJin Ko
Journal of the Korean Society of Radiology.2013; 7(6): 409. CrossRef

Cone-Beam CT Image-Guided Radiosurgery of Brain Metastasis : Technical Note and Clinical Application: Sei-One Shin, Sang Mo Yun; Yeungnam Univ J Med. 2007;24(2 Suppl):S591-597. Published online December 31, 2007; DOI: https://doi.org/10.12701/yujm.2007.24.2S.S591

1,102 View
4 Download

Abstract PDF: Background
：This study was performed to test feasibility of CBCT(cone-beam computerized tomography) guided radiosurgery. Materials and Methods：We used CBCT which was mounted on a retractable arm at 90° to the treatment source. CBCT images were overlapped on the digitally reconstructed images from simulation CT scan. Then, 3 dimensional volumetric CT image matching was performed. If there were any positioning errors, automated patient re-positioning was done.
Results
：A radiosurgery treatment plan was carried out with a set of specially designed multiple non-coplanar arcs. The goal of plan was to deliver single session 18 Gy at periphery of the target. We treated a patient with a solitary brain metastasis from left upper lung cancer. Serial imaging study for treatment response revealed a satisfactory result with no remarkable treatment related side effects.
Conclusion
：CBCT image guided radiosurgery system is very simple and could be a convenient image guiding modality for stereotactic radiosurgery or fractionated radiotherapy with an acceptable geometric accuracy and radiation exposure.

Electromagnetic Fields in General Hospital.: Sei One Shin, Sang Mo Yun, Hyoun Jin Shin, Hyun Soo Ahn, Hee Deok Ahn; Yeungnam Univ J Med. 2004;21(2):167-176. Published online December 31, 2004; DOI: https://doi.org/10.12701/yujm.2004.21.2.167

1,407 View
2 Download

Abstract PDF: BACKGROUND
Electromagnetic fields (EMF) are ubiquitous in modern society including medical field. As the technology of medical instruments and telecommunications has developed rapidly, it has influenced on our lives in many ways. Modern medical practice requires high quality medical equipments, which have a great deal of electromagnetic interference and susceptibility. The purpose of this study were to evaluate electromagnetic condition under usual clinical condition and to suggest a practical guideline in general hospital. MATERIALS AND METHODS: The actual state of the electromagnetic interference in the medical field was studied under usual clinical conditions including operating rooms, intensive care units, magnetic resonance imaging unit, and hyperthermia unit. RESULTS: There was considerable noise as a result of electromagnetic fields from medical equipments including electrosurgical units and hyperthermia unit, and cellular phones, which could induce serious functional derangements of functioning medical devices. CONCLUSION: It will be necessary to evaluate the individual electromagnetic situations under various medical conditions and to define a limited zone for cellular phone as well as reposition medical equipments to secure a safer medical practice and to minimize electromagnetic interference.

Author index