• Radiation Oncology Journal
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• 제14권4호
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• pp.255-264
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• 1996

Purpose : Paclitaxel is a chemotherapeutic agent with potent microtubule stabilizing activity that arrests cell cycle in $G_2$-M Because $G_2$-M is the most radiosensitive Phase of the cell cycle, paclitaxel has potential as a cell cycle- specific radiosensitizer. This study was designed to investigate the ability of paclitaxel to increase the radiotoxicity in normal small bowel mucosa of the rat. materials and Methods : A sigle intraperitoneal infusion of paclitaxel (10mg/kg), and a single irradiation(8 Gy, x-ray) to the whole abdomen and combination of radiation(8 Gr, x-ray) 24 hours after paclitaxel infusion in the rats were done. The changes of jejunal mucosa, and kinetics of mitotic arrest and apoptosis in the jejunal crypt were defined at 6 hours - 5 days after each treatment histologically. Results : Paclitaxel blocked jejunal crypt cell in mitosis and induced minmal apoptosis. Mitotic arrest by paclitaxel was peaked at 6 hours after infusion and returned to normal by 24 hours. Radiation induced apoptosis and peaked at 6 hours and returned to normal by 24 hours. Combination of paclitaxel and radiation blocked crypt cell in mitosis at 3 days and induced apoptosis slightly at 6 hours and 24 hours and returned to normal by 3 days. The incidence of apoptosis in combined group at 6 hours was slightly higher than normal control but significantly lower than radiation alone group. The major changes of jejunal mucosa were nuclear vesicle and atypia which were appeared at 6 hours - 3 days and returned to normal by 5 days The degree of the mucosal changes are not different in 3 groups except for absence of inflmmatory reaction in radiation group. Conclusion : Mitotic arrest by paclitaxel was peaked at 6 hours and returned to normal by 24 hours and paclitaxel induced minimal apoptosis. Radiation induced apoptosis, peaked at 6 hours and returned to normal by 24 hours. Radiation-induced apoptosis was less in combined group which suggested that paclitaxel have a radioprotective effect when radiation was given 24 hours after paclitaxel infusion.

• Radiation Oncology Journal
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• 제12권1호
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• pp.33-42
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• 1994

From 1982 to 1991, sixteen Patients with primary non-Hodgkin's lymphoma of the central nervous system(CNS) were seen at Kyung Hee University Hospital. The most common subtypes were large, noncleaved cell lymphoma and immunoblastic lymphoma of B cells. Lesions most commonly involved were the parietal lobes and/or deep nuclei. Positive cerebrospinal fluid cytology was rare at initial presentation. Sixteen patients were treated with surgical biopsy or resection followed by whole brain radiotherapy at a median dose of 40 Gy(range=30-50 Gy) with variable boost doses. Of 16 patients who underwent surgery and postoperative radiotherapy, fourteen patients died between 2 and 49 months following treatment, and two are alive with no evidence of disease at 8 and 22 months. The 1-and 2-year survival rates were 55.6$ \% $ and 34.7$ \% $, respectively with 12 months of median survival. Patterns of failure were analyzed in eleven patients of total 16 patients. Failure at the original site of involvement was uncommon after radiotherapy treatment. In contrast, failure in the brain at sites other than those originally invovled was common in spite of the use of whole brain irradiation. Failure occurred in the brain 11/16(68.7$ \% $), in spinal axis 4/16(25.0$ \% $). The age, sex, location of involvement within CNS, numbers of lesion, or radiation dose did not influence on survival. The authors conclude that Primary CNS lymphoma is a locally aggressive disease that is poorly controlled with conventional radiation therapy. The limitation of current therapy for this disease are discussed, and certain promising modality should be made in regarding the management of future patients with this disease.

• Radiation Oncology Journal
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• 제17권2호
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• pp.166-171
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• 1999

Purpose : To get the data for public information and education of medical students about radiation therapy (RT). Materials and Methods : We evaluated the knowledge and attitudes towards the RT and cancer in the third grade medical students who did not receive a lecture before starting the poly-clinic education about radiation oncology in our medical school, We obtained a total of 142 answers from the students that completed the questionnaire. Results : More than half of the third grade medical students answered 1 question correctly and 5 questions incorrectly among 6 questions about knowledge of RT. Incorrect answers were done about the frequency of RT, hair loss, the period of RT, re-RT, cost of RT, Fifty-six percent of students didn't wish to prolong the survival time from 1 year to 3 years with long courses of chemotherapy and RT. They had bad images about cancer of colorectum, lung, esophagus, liver, breast, cervix which consist of 56.3$\%$ of patients receiving RT. Conclusions : Public information about the basic points of RT should be considered. Also the students showed the pessimism about the anticancer treatments such as chemotherapy and RT, so the exact results and positive aspects of anticancer treatment should be educated more. Especially it is needed to inform the students and the public the positive aspects of RT in some cancers (colorectal, lung, esophageal, hepatic, breast, cervix cancers) which the students had bad images about.

• Radiation Oncology Journal
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• 제17권3호
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• pp.203-208
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• 1999

Purpose : To evaluate whether spontaneous apoptosis has prognostic value among patients with squamous cell carcinoma of lung. Materials and Methods : Material from 19 patients who received thoracic irradiation between 1990 and 1994 was analyzed. Their stages were II (1), IIIa (8), IIIb (5), and IV (5). Patients were observed from 5 to 67 months (median : 17 months). The spontaneous apoptosis index (AI) and p53 mutation were measured by immunohistochemical stains. Results : AI was found to range from 0 to $1\%$ (median $0.4\%$). Patients with low AI ($AI{\leq}$median) had a much higher distant metastasis rate at diagnosis than patients with high AI. By analysis of prognostic factors for survival, M stage was significant in univariate analysis. AI, chemotherapy, M stage, T stage, and stage were significant in multivariate analysis. The correlation between the AI and p53 mutation was not seen. Conclusion : AI was related with distant metastasis at diagnosis and not with p53 mutation. Also low AI group tended to have shorter survival time than high AI group.

• Radiation Oncology Journal
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• 제21권2호
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• pp.158-166
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• 2003

Purpose: To propose a conceptual design of a novel source for intensity modulated brachytherapy. Materials and Methods: The source design incorporates both radioactive and shielding materials (stainless steel or tungsten), to provide an asymmetric dose intensity in the azimuthal direction. The intensity modulated intravascular brachytherapy was performed by combining a series of dwell positions and times, distributed along the azimuthal coordinates. Two simple designs for the beta-emitting sources, with similar physical dimensions to a $^{90}Sr/Y$ Novoste Beat-Cath source, were considered in the dosimetric feasibility study. In the first design, the radioactive and materials each occupy half of the cylinder and in the second, the radioactive material occupies only a quater of the cylinder. The radial and azimuthal dose distributions around each source were calculated using the MCNP Monte Carlo code. Results: The preliminary hypothetical simulation and optimization results demonstrated the 87$\%$ difference between the maximum and minimum doses to the lumen wall, due to off-centering of the radiation source, could be reduced to less than 7$\%$ by optimizing the azimuthal dwell positions and times of the partially shielded intravascular brachytherapy sources. Conclusion: The novel brachytherapy source design, and conceptual source delivery system, proposed in this study show promising dosimetric characteristics for the realization of intensity modulated brachytherapy in intravascular treatment. Further development of this concept will center on building a delivery system that can precisely control the angular motion of a radiation source in a small-diameter catheter.

• The Korean Journal of Nuclear Medicine
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• 제24권2호
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• pp.317-324
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• 1990

Liposome was labelled with $^{99m}Tc$ after negative charged liposome was formed with combination of a few lipid components. $^{99m}Tc$ liposome was injected through the tail vein of C3H mice bearing fibrosarcoma and biodistribution of $^{99m}Tc$ liposome was evaluated. The results were as follows: 1) We confirmed formation of liposome which was small unillamellar and multilamellar vesicles. 2) In this experiment the optimal concentration of $SnCl_2$ was $156{\mu}g/ml$ to label liposome with $^{99m}Tc$ and labelling efficiency was 95%. 3) The labelled liposome was stable when it was incubated with human serum for 24 hours. Mean labelling efficiency was 94% at 24 hour. 4) The main uptake sites of Tc-99m liposome were liver and spleen. It showed significantly higher uptake than $^{99m}Tc$ HSA (p < 0.001). 5) $^{99m}Tc$ liposome uptake in tumor tissue was not significantly higher than $^{99m}Tc$ HSA uptake. In conclusion, $^{99m}Tc$ liposome disclosed high labelling efficiency and was highly stable. Liver and spleen were main uptake sites of $^{99m}Tc$ liposome. The uptake mechanism of $^{99m}Tc$ liposome also seemed to be different from that of $^{99m}Tc$ HSA. We conclude that $^{99m}Tc$ liposome would be a promising agents for the imaging of some tumor.

• Journal of the Korean Magnetics Society
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• 제25권6호
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• pp.208-218
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• 2015

Recently, radiation therapy is used in the CT existing conventional two-dimensional radiation image, and set the size and location of the tumor in a manner that the image is going to change the treatment plan. After using the simulation using CT, radiation therapy it is four-dimensional or three-dimensional treatment made possible. and radiation therapy became the more effective ever before. High technology radiation therapy such as the treatment of SRS,IMRT, IGRT, SBRT, is a need to try contemplating the possibility to apply appropriate analysis and situation, so it has its own characteristics. and then it is believed that it is necessary to analyze and try it worries the proper applicability of the situation. The configuration of the various treatment that is applicable in many hospitals is necessary to try to determine how to practically apply the patients. Critical organs surrounding tumor give a small dose to avoid side effects and then the tumor has the therapeutic effect by providing a larger dose than before the radiation treatment.

• Radiation Oncology Journal
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• 제16권3호
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• pp.347-350
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• 1998

Purpose : This study is to see how much proportion of the patients receiving radiation therapy drop out during radiation therapy and to analyze the reason for the incomplete treatment. Materials and Methods : The base population of this study was 1,100 patients with registration numbers 901 through 2,000 at Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea. Authors investigated the incidence of incomplete radiation therapy, which was defined as less than 95$\%$ of initially planned radiation dose, and the reasons for incomplete radiation therapy. Results : One hundred and twenty eight patients (12$\%$) did not complete the planned radiation therapy. The performance status of the incompletely treated patients was generally Poorer than that of the base population, and the aim of radiation therapy was more commonly palliative. The most common reason for not completing the planned treatment was the patients' refusal of further radiation therapy because of the distrust of radiation therapy and/or the poor economic status. Conclusion : Careful case selection for radiation therapy with consideration of the socioeconomic status of the patients in addition to the clinical indication would be necessary for the reduction of incomplete treatment, especially in the palliative setting.

• Journal of Yeungnam Medical Science
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• 제7권2호
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• pp.55-66
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• 1990

This research is focused on the attitudes toward dying and hospice. 4subjects groups are Ca. patient, Ca. patien's family, elderly, medical personnel. A 40 questionare was filled out by each participant. For this study chi-square and T-test was done. The result were as follows : 1. Telling the truth 61.2% of all subject groups agreed upon telling the impending death. About 40% of elderly groups and cancer patient group were disagreed which is the highest percentage in all groups. Particularly medical personnel group were remarkably high in telling the truth. 2. Attitudes of medical personnels 43.3% of all groups agreed upon medical personnels prefer to avoid dying patient. In medical personnel group. 44% of respondents disagred comparably higher than other group. But 37.7% of medical personnel agreed. It showed that medical personnels admitted their negative feelings toward dying patient in considerable degree. 3. Attitudes toward mechanical assistance for life-expanding or hopeless patient. 44.8% of all groups disagreed upon mechanical assistance for hopeless case. Elderly (54.9%) and medical personnels (50%) disagreed, which is higher than cancer patient (33.3%) and (22.8%) of cancer patient's family. 4. Special facility and educational preperation for dying patient. 67.4% of all groups agreed upon the needs of special facility for dying, 81.3% of medical personnels agreed which is highest percentage in all group. 5. Attitudes of family members of dying patient. 82.3% of all groups agreed upon the family members feel annoyed at dying patient. 34% of cancer patient's family member and 48% of cancer patients group agreed, but elderly group showed highest percentage(84%). 6. Perception of dying patient about imminent death. 58.3% of all group thought dying patients are aware of their impanding death even though they had not beent told. 77.3% of medical personnel agreed which is highest percentage in all group.

• Progress in Medical Physics
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• 제17권1호
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• pp.40-46
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• 2006

Hepatoma is one of 3 most common malignancies in Korea, the survival rate is not improved since last decades because of delayed diagnosis and limited treatment conditions. Radiation was one of treatment options but the impact on the survival is not remarkable. High dose exposure to target area was suggested for improved effect but low tolerance dose of normal liver tissue is the main limited factor. IMRT is the advanced form of 3DCRT, for focusing high dose on target with minimal dose to surrounding normal tissues. Motion of the tumor by respiration, cardiac pulsation and peristalsis is the main treatment harrier of IMRT for treatment of hepatoma patients. Development of QA technique for acceptable geometrical uncertainties and dose error on target volume is essential for IMRT in clinical treatment but proper QA technique is not yet developed. This study compared the verification film dosimetry with measured dose in phantom and calculated dose in planning computer on exactly same conditions of patient treatments. Within 3% dose differences between 3 groups were confirmed. We suggest that our verification QA technique is easy, economic, iterative and acceptable in clinical application for advanced hepatoma patients.