• Radiation Oncology Journal
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• v.12 no.3
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• pp.387-392
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• 1994

Purpose : This study was done to confirm the reference point variation according to variation in applicator configuration in each fractioation of HDR ICR. Materials and Methods : We analyzed the treatment planning of HDRICR for 33 uterine cervical cancer patients treated in department of therapeutic radiology from January 1992 to February 1992. Analysis was done with respect to three view points-Interfractionation A point variation, interfractionation bladder and rectum dose ratio variation, interfractionation treatment volume variation. Interfractionation A point variation was defined as difference between maximum and minimum distance from fixed rectal point to A point in each patient. Interfractionation bladder and rectum dose ratio variation was defined as difference between maximum and minimum dose ratio of bladder or rectum to A point dose in each patient, Interfractionation treatment volume variation was defined as difference between miximum and minimum treatment volume which absorbed over the described dose-that is, 350 cGy or 400 cGy-in each patient. Results The mean of distance from rectum to A point was 4.44cm, and the mean of interfractionation distance variation was 1.14 cm in right side,1.09 cm in left side. The mean of bladder and rectum dose ratio was $63.8\%$ and $63.1\%$ and the mean of interfractionation variation was $14.9\%$ and $15.8\%$ respectively. With fixed planning administration of same planning to all fractionations as in first fractionation planning-mean of bladder and rectum dose ratio was $64.9\%$ and $72.3\%$.and the mean of interfraction variation was $28.1\%$ and $48.1\%$ reapectively. The mean of treatment volume was $84.15cm^3$ and the interfractionation variation was $21.47cm^2$. Conclusion : From these data, it was confirmed that there should be adapted planning for every fractionation ,and that confirmation device installed in ICR room would reduce the interfractionation variation due to more stable applicator configuration.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.183-186
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• 1986

In brachytherapy of uterine cervical cancer using the high dose rate remote afterloading system, it is of prime importance to determine the position of the radiation sources and to estimate the irradiation time. However, calculation with manual method is so time consuming and laborious, that authors designed a software as an aid to intracavitary radiotherapy Planning using the personal computer to obtain the precision of treatment without being too complicated for routine use. Optimal source arrangement in combination with dose rate at each specific points and irradiation time can be easily determined using this software in several minutes.

• Radiation Oncology Journal
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• v.8 no.1
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• pp.51-57
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• 1990

Retrospective analyses were done of 48 patients with early glottic cancer, 31 with T1NOMO and 17 with T2NOMO, who received radiation therapy from March 1979 to August 1984 at Seoul National University Hospital with the prescribed full dosage. The median follow-up period was 67 months (range: 34 months$\~$126 months), and the percent follow-up for longer than five years was $85.4\%$ The five-year actuarial overall and recurrence-free survival rates of the whole patient group were $83.2\%\;and\;69.4\%$, respectively. The five-year actuarial overall and recurrence-free survival rates of the T1 group were $87.1\%\;and\;76.0\%$, and those of the T2 group were $76.5\%\;and\;58.2\%$, respectively. Possible causes of the failures to radiation therapy, the dose-response relationship, association with the second malignant tumors, and some recommendations for better treatment outcome are analyzed and discussed.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.115-123
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• 1998

Purpose : This study was tried to evaluate the effect of the partial body fractionated irradiation on the frequency of chromosomal aberration. Materials and Methods : In three patients with uterine cervix carcinoma, chromosomal aberrations were analyzed during fractionated external beam radiotherapy Radiation field included whole pelvis and total dose was 5040 cGy in 28 fractions. Results : The values of the frequency of dicentrics and rings (Ydr) in pre-irradiated peripheral lymphocytes in three patients were 0.0060, 0.0000, and 0.0029, respectively. The frequency of dicentrics and rings, estimated during the course of radiotherapy, increased with radiation dose and best fitted to the linear equation, $Ydr=7.31{\times}10^{-5}D(cGy)+1.45{\times}10^{-2}$. The frequency of dicentrics and rings among the cells with dicentric and/or ring(Qdr) also showed increasing tendency and best fitted to the linear equation, $Qdr=1.01{\times}10^{-4}D(cGy)+1.04$. Conclusion : Ydr increased linearly with radiation dose in the dose range of our study, and Qdr showed increasing tendency with dose.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.141-148
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• 1987

The ultimate goal of radiotherapy is to result in complete local control of tumor while sparing the surrounding normal tissues as much as possible. Since the development of CT in 1970s, patient's anatomical normal tissues and the site and extent of infiltration of tumor were identified almost accurately. In addition, the isodose distribution of delivered radiation to target tumor was shown in each cross-section. In the treatment planning of head and neck cancers, CT-reconstruction provided almost 3-dimensinonal inter-relationship between tumor and normal tissues. The utilization of imaging system of the CT scanner made it possible to illustrate in superposition the patient structure image, the radiation beams, and the isodose distributions. Thus it was possible to deliver radiation enough to control the local disease, and to avoid unnecessary administration of radiation to normal tissue such as spinal cord. CT-reconstructed image in axial, sagittal, and coronal planes suggested 3-dimensional radiotherapy treatment planning be possible and practical instead of conventional 2-dimensional planning at coronal plane.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.309-313
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• 2000

The metastasis of uterine leiornyosarcorna to the neck node has not been reported previously and the radiotherapy has been rarely used for the metastatic lesion of the other sites. We report a case of neck metastasis from a uterine leiornyosarcorna, which developed 10 months after surgery and postoperative pelvic radiotherapy. It also involved the parapharyngeal space, adjacent spine, and spinal canal. The metastatic neck mass was inoperable, and was treated by neck radiotherapy (6,000 cGy) and chemotherapy including taxol and carboplatin. The mass has regressed progressively to a nearly impalpable state. She has never developed spinal cord compression syndrome, and has maintained good swallowing for eight months since the neck radiotherapy and chemotherapy. Since the extensive metastatic neck mass showed good local response to high dose radiotherapy and chemotherapy, both treatments may be considered for an unresectable metastatic leiornyosarcorna.

• Journal of Radiation Protection and Research
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• v.20 no.3
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• pp.163-168
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• 1995

The Radio-frequency electromagnetic(RFEM) spectrum is defined as waves that range in frequency from>0 to $3{\times}1012Hz$. Although there are several thousands of reports that present data or opinion of the biological response to RFEM radiation, no consensus has emerged regarding thresholds and mechanisms of injury. This review presents a overview of the subject on mechanisms of interaction of RFEM fields with tissue, chromosomal and mutagenic effect. carcinogenic effects. The scope of the review is expanded to include systemic effects such as those on reproduction, growth, and development, hematological effects. Some biological end points, those with associated with behavior and cataractogenesis is discussed.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.127-132
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• 2000

Purpose : To determine if the tumor intersitial fluid pressure (TIFP) and/or its change in patients with metastatic Iymph node in head and neck area can predict radiotherapy outcome. Materials and Methods : In 26 biopsy Proven metastatic Iymph node Patients in head and neck area with accessible by direct inspection and palpation, and of sufficient thickness (>1 cm) to permit accurate needle placement, we measured TIFP at cervical Iymph node before and during radiotherapy. Tumor size was measured clinically and radiologically. Results : The mean preradiotherapy TIFP was 24.7 mmHg. Preradiotherapy TIFP had marginally significant relationship with tumor size (p=0.06). Preradiotherapy TIFP significantly decreased when tumor size decreased (p=0.009). Preradiotherapy TIFP was not different between complete response group and group with partial or less response (p=0.75). Radiotherapy outcome was not different between group with above and group with below than average TIFP (p=0.229). TIFP decreased 36mmHg in complete response group and 29.7 mmHg in group with partial or less response. Conclusion :The mean TIFP was elevated with 24.7 mmHg. Preradiotherapy TIFP had marginally significant relationship with tumor size (p=0.06). TIFP decreased 36 mmHg in complete response group and 29.7 mmHg in group with partial or less respone but there was no statistically significant relationship in two groups.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.315-321
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• 1994

Ameloblastoma is a rare epithelial tumor of the jaw, comprising approximately $1\%$ of all tumors and cysts of odontogenic origin. The tumor has been the subject of much controversy and cliscussion. Amelobiastoma is slow growing, locally invasive, and has a high rate of total recurrence, but rarely metastasizes. This neoplasm has been considered radioresistant, so it has been treated with surgery primarily except some cases. Recently it is suggested that ameloblastoma is radiosensitive, so radiation therapy (RT) would be used in addition to or, in certain cases, in place of surgery. We report these two cases which were referred to the Department of Therapeutic Radiology for deciding tile need of postoperative RT, because amelobiastoma is rare and has been known tot be radioresistant. Postoperative RT was given to one of these two Patients.

• Radiation Oncology Journal
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• v.4 no.2
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• pp.165-172
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• 1986

In electron therapy, lead cutout or low-melting alloy block is used for shaping the field. Material for shaping electron field affects the output factor as wet 1 as the collimation system. The authors measured the output factors of electron beams for shaped fields from Clinac-18 using ionization chamber of Farmer type in polystyrene phantom. They analyzed the parameters that affect the output factors. The output factors of electron beams depend on the incident energy, collimation system and size of shaped field. For shaped field the variation of output factor for the field size (A/P) has appearence of a smooth curve for all energy and all applicator collimator combination. The output factors for open field deviate from the curves for shaped fields. An output factor for a given field can be calculated by equivalent field method such as A/P method, if a combination of applicator and collimator is fixed.