PURPOSE: .In FSRT (Fractionated stereotactic radiotherapy) planning, we studied the usefulness between multiple arc FSRT and conformal FSRT by comparing tumor shape and DVH(dose volume histogram). MATERIALS AND METHDS: In Chungnam Univ. hospital, we had treated the sixteen patients with FSRT from Aug. 1997 to Dec. 1998. In choosing multiple arc FSRT or conformal FSRT, we had considered multiple arc FSRT if tumor shape was similar to sphere or the value of IF was less than 1.25, conformal FSRT if tumor shape was very irregular or IF was more than 1.3. For evaluation of treatment planning, we had considered the appropriate DVH for tumor volume and for critical organs. RESULT: The errors between reference point and the coordinates point on AP, Lat radiography were less than 1 mm before treatment. We had planned 3~5 arcs for multiple arc FSRT, 5~6pots for conformal FSRT. The mean dose distribution of tumor volume of cumulative DVH between multiple arc FSRT and conformal FSRT was 90.6, 86%, respectively. The dose of critical organs irradiated was less than 5% maximum dose of cumulative DVH. CONCLUSION: We had obtained the similar value between multiple arc FSRT and conformal FSRT, so that we had appropriate treatment planning of FSRT for multiple arc FSRT and conformal FSRT according to tumor shape and size.
Chungcheongnam-do ; Humans ; Radiography ; Tumor Burden

PURPOSE: An investigation has been carried out on the factors which affect the response reading of thermoluminescent dosimeters (TLD-100) loaded with thin material in high energy photon. The aim of the study was to assess the energy response of TLD-100 to the therapeutic ranges of photon beam. MATERIALS AND METHODS: In this technique, TLD-100 (abbreviated as TLD) chips and three different thin material (Tin, Gold, and Tissue equivalent plastic plate) which mounted on the TLD chip were used in the clinical photon beam. The thickness of each metal plates was 0.1 mm and TE plastic plate was 1 mm thick. These compared with the photon energy dependence of the sensitivities of TLD (normal chip), TLD loaded with Tin or Gold plate, for the photon energy range 6 MV to 15 MV, which was of interest in radiotherapy. RESULTS: The enhancement of surface dose in the TLD with metal plate was clearly detected. The TLD chips with a Gold plate was found to larger response by a factor of 1.83 in 10 MV photon beam with respect to normal chip. The sensitivity of TLD loaded with Tin was less than that for normal TLD and TLD loaded with Gold. The relative sensitivity of TLD loaded with metal has little energy dependence. CONCLUSION: The good stability and linearity with respect to monitor units of TLD loaded with metal were demonstrated by relative measurements in high energy photon (6~15 MV) beams. The TLD laminated with metals embedded system in solid water phantom is a suitable detector for relative dose measurements in a small beam size and surface dose.
Metals ; Plastics ; Radiotherapy ; Tin ; Water

PURPOSE: The purpose of this study is to investigate fundamental aspects of the dose response of fluorescent screen-based electronic portal imaging devices (EPIDs). MATERIALS AND METHODS: We acquired scanned signal across portal planes as we varied the radiation that entered the EPID by changing the thickness and anatomy of the phantom as well as the air gap between the phantom and the EPID. In addition, we simulated the relative contribution of the scintillation light signal in the EPID system RESULTS: We have shown that the dose profile across portal planes is a function of the air gap and phantom thickness. We have also found that depending on the density change within the phantom geometry, errors associated with dose response based on the EPID scan can be as high as 7%. We also found that scintillation light scattering within the EPID system is an important source of error. CONCLUSION: This study revealed and demonstrated fundamental characteristics of dose response of EPID, as relative to that of ion chambers. This study showed that EPID based on fluorescent screen cannot be an accurate dosimetry system

PURPOSE: To assess the histomorphologic changes in the rat lung injury induced by radiation, to determine whether captopril reduces the rat lung injury and to evaluate change in TNF-alpha and TGF-beta in rat lung damage by radiation and captopril. METHODS AND MATERIAL: Right lungs in male Sprague-Dawley rats were divided irradiation alone (10, 20, 30 Gy) or radiation (same dose with radiation alone group) with captopril (500 mg/L). Radiation alone group were sacrificed at twelve hours and eleven weeks after radiation and radiation with captopril group (captopril group) were sacrificed at eleven weeks after radiation with captopril. We examined the light microscope and electron microscopic features in the groups. RESULTS: In radiation alone group, there were patch parenchymal collapse and consolidation at twelve hours after radiation. The increase of radiation dose shows more prominent the severity and broader the affected areas. Eleven weeks after radiation, the severity and areas of fibrosis had increased in proportion to radiation dose given in the radiation alone group. There was notable decrease of lung fibrosis in captopril group than in radiation alone group. The number of mast cells rapidly increased with increase of radiation dose in radiation alone group and the degree of increase of mast cell number and severity of collagen accumulation more decreased in captopril group than in radiation alone group. In radiation alone group, expression of TNF-alpha and TGF-beta increased according to increase of radiation dose at twelve hours after radiation in both group. At eleven weeks after radiation, expression of TGF-beta increased according to increase of radiation dose in radiation group but somewhat decreased in captopril group. In the captopril group the collagen deposition increased but less dense than those of radiation alone group. The severity of perivascular thickening, capillary change, the number and degranulation of mast cells more decreased in the captopril group than in the radiation alone group. CONCLUSION: It is concluded that the effect of captopril in the rat lungs after radiation was considered to be due to its effect on inhibition of mast cells and reduction of collagen deposition, and captopril may be protect in lung damage after radiation. We observed expression of TNF-alpha and TGF-beta increased at the early phase after radiation and expression of TGF-beta increased in proportion to increase of radiation dose at the chronic phase after radiation. This results will contribute to future investigation in reduction mechanism of captopril in lung damage after radiation.
Animals ; Capillaries ; Captopril* ; Collagen ; Fibrosis ; Humans ; Lung Injury* ; Lung* ; Male ; Mast Cells ; Radiation Pneumonitis* ; Rats* ; Rats, Sprague-Dawley ; Transforming Growth Factor beta ; Tumor Necrosis Factor-alpha

PURPOSE: To elucidate the effects of pentoxifylline and diltiazem on the late response of the salivary glands of the rat after irradiation. MATERIALS AND METHODS: Sixteen Sprague-Dawley rats were divided into 4 groups : (a) irradiation alone (b) irradiation with pentixifylline (PTX) (c) irradiation with diltiazem (DTZ) (d) irradiation with both PTX and DTZ. Irradiation was given in a single fraction of 16 Gy using 4 MV photon energy through an anterior port encompassing the left side of the salivary gland leaving the right side of salivary gland as a contol. PTX, 20 mg/kg and/or DTZ, 50 mg/kg were infused intraperitoneally before irradiation. Two rats from each group were sacrificed on the 10th week and the rest was sacrificed on the 16th week after irradiation. Histopathologic examinations were undertaken for each section and the proportion of vacuolated cells out of the total number of cells under light microscopic fields was calculated. The statistical significance in the difference of the proportion of the vacuolated cells among the experimental groups was evaluated by a x2-test. RESULTS: Irradiated salivary glands of the 10th week group revealed markedly increased number of vacuolated cells compared to those of unirradiated control. The proportion of vacuolated cells was significantly reduced in both the PTX group (p value=0.001) and the combined PTX and DTX group compared to those of irradiation alone group. The DTZ alone group did not reveal the significant reduction of vacuolated cells compared to those of irradiation alone group (p value, >0.05). The 16th week groups revealed similar findings to those of the 10th week group, but the degree of chronic inflammatory cell infiltrates and interstitial fibrosis was increased and the number of acinar cells was reduced compared to those of the 10th week group. CONCLUSIONS: PTX significantly reduced the late radiation response of salivary glands, but DTZ did not reduce the same degree as PTX did. Taking the positive results of this study into consideration, it seems reasonable to apply PTX into the clinical trial for the head and neck irradiation to reduce the late radiation sequelae of salivary glands in the near future. At the same time the further experiment to clarify the subcellular mechanisms involved in PTX should be preceded.
Acinar Cells ; Animals ; Diltiazem* ; Fibrosis ; Head ; Neck ; Pentoxifylline* ; Rats* ; Rats, Sprague-Dawley ; Salivary Glands*

PURPOSE: The expression pattern of c-jun by ionizing radiation according to cell growth state (exponential growth phase vs. stationary phase) and its relationship with cell cycle redistribution were investigated. MATERIALS AND METHODS: The exponential growth phase (day 4) and stationary phase (day 9) cells were determined from cell growth curve according to the elapse of days in CaSki. The cells were irradiated using 6 MV X-ray with a dose of 2 Gy at a fixed dose rate of 3 Gy/min. Northern blot analysis was performed with total cellular RNA and cell cycle distribution was analyzed using flow cytometry according to time-course after irradiation. RESULTS: The maximum expression of c-jun occurred 1 hour after irradiation in both exponential growth and stationary phase cells. After then c-jun expression was elevated upto 6 hours in exponential growth phase cells, but the level decreased in stationary phase cells. Movements of cells from G0-G1 to S, G2-M phase after irradiation were higher in exponential growth phase than stationary phase. CONCLUSION: c-jun may be involved in the regulation of cellular proliferation according to the growth states after irradiation.
Blotting, Northern ; Cell Cycle ; Cell Line* ; Cell Proliferation ; Flow Cytometry ; Radiation, Ionizing ; RNA

PURPOSE: To evaluate prognostic factors and survival rates of the patients who received radiation therapy for locally recurrent uterine cervical cancer after curative surgery. MATERIALS AND METHODS: Between October 1983 and July 1996, fifty three patients who received radiation therapy for locally recurrent cervical cancer after curative surgery at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, The Catholic University of Korea were analysed retrospectively. Age at diagnosis ranged from 33 to 69 years (median 53 years). Pathological analysis showed that forty five (84.9%) patients had squamous cell carcinoma, seven (13.2%) patients had adenocarcinoma, and one (1.9%) patient had adenosquamous cell carcinoma. The interval between hysterectomy and tumor recurrence ranged from 2 months to 25 years (mean 34.4 months). The recurrent sites were vaginal stump in 41 patients (77.4%) and pelvic side wall in 12 patients (22.6%). Recurrent tumor size was devided into two groups : less than 3 cm in 43 patients (81.1%) and more than 3 cm in 10 patients (18.9%). External beam irradiation of whole pelvis was done first up to 46.8 Gy to 50.4 Gy in 5 weeks to 6 weeks, followed by either external beam boost to the recurrent site in 18 patients (34%) or intracavitary irradiation in 24 patients (45.3%). Total dose of radiation ranged from 46.8 Gy to 111 Gy (median 70.2 Gy). Follow up period ranged from 2 to 153 months with a median of 35 months. RESULTS: Overall response rate was 66% (35/53). Among them, six patients (17.1%) relapsed between 7 months and 116 months after radiation therapy (mean 47.7 months). Therefore overall recurrence rate was 45.3%. Overall five-year actuarial survival rate was 78.9% and distant failure rate was 10% (5/50). The significant prognostic factors affecting survival rate were interval between primary surgery and tumor recurrence (p=0.0055), recurrent tumor size (p=0.0039), and initial response to radiation therapy (p=0.0428). Complications were observed in 10 (20%) patients, which included mild to moderate lower gastrointestinal, genitourinary, or skin manifestations. One patient died of pulmonary embolism just after intracavitary irradiation. CONCLUSION: Radiation therapy is the effective treatment for the patients with locally recurrent cervical cancer after curative surgery. These results suggest that interval between primary surgery and tumor recurrence, recurrrent tumor size, and initial response to radiation therapy were significant prognostic factors for recurrent cervical cancer.
Adenocarcinoma ; Carcinoma, Squamous Cell ; Diagnosis ; Follow-Up Studies ; Humans ; Hysterectomy ; Korea ; Pelvis ; Pulmonary Embolism ; Radiation Oncology ; Radiotherapy* ; Recurrence ; Retrospective Studies ; Skin Manifestations ; Survival Rate ; Uterine Cervical Neoplasms*

Intraocular metastasis is the most common malignancy of the eye. The frequency of intraocular metastasis in all the patients dying of cancer is about 12% and ocular metastases will be detected more frequently in the future because the patients with malignant tumor are now living longer. Intraocular metastasis can cause a serious clinical problem such as blindness. The early recognition and treatment of intraocular metastasis are very important clinical oncologic issues to maintain vision and to maximize the quality of life. However, significance of intraocular metastasis is still under-evaluated for practicing oncologists. External beam radiotherapy is a safe, effective palliative treatment in terms of preserving both the vision and the eye globe.
Blindness ; Eye ; Humans ; Neoplasm Metastasis ; Palliative Care ; Quality of Life ; Vision, Ocular

PURPOSE: This study was a retrospective evaluation of the efficacy of stereotactic radiosurgery (SRS) in patients with >4 metastases to the brain. MATERIALS AND METHODS: Between January 2004 and December 2006, 68 patients with > or = 4 multiple brain metastases were included and reviewed retrospectively. Twenty-nine patients received SRS and 39 patients received whole brain radiotherapy (WBRT). Patients with small cell lung cancers and melanomas were excluded. The primary lesions were non-small cell lung cancer (69.0%) and breast cancer (13.8%) in the SRS group and non-small cell lung cancer (64.1%), breast cancer (15.4%), colorectal cancer (12.8%), esophageal cancer (5.1%) in the WBRT group. SRS involved gamma-knife radiosurgery and delivered 10~20 Gy (median, 16 Gy) in a single fraction with a 50% marginal dose. WBRT was delivered daily in 3 Gy fractions, for a total of 30 Gy. After completion of treatment, a follow-up brain MRI or a contrast-enhanced brain CT was reviewed. The overall survival and intracranial progression-free survival were compared in each group. RESULTS: The median follow-up period was 5 months (range, 2~19 months) in the SRS group and 6 months (range, 4~23 months) in the WBRT group. The mean number of metastatic lesions in the SRS and WBRT groups was 6 and 5, respectively. The intracranial progression-free survival and overall survival in the SRS group was 5.1 and 5.6 months, respectively, in comparison to 6.1 and 7.2 months, respectively, in the WBRT group. CONCLUSION: SRS was less effective than WBRT in the treatment of patients with >4 metastases to the brain.
Brain ; Breast Neoplasms ; Carcinoma, Non-Small-Cell Lung ; Colorectal Neoplasms ; Disease-Free Survival ; Esophageal Neoplasms ; Follow-Up Studies ; Humans ; Lung Neoplasms ; Melanoma ; Neoplasm Metastasis ; Radiosurgery ; Retrospective Studies

PURPOSE: To evaluate the long-term results after breast-conserving surgery and radiation therapy in early breast cancer in terms of failure, survival, and cosmesis. MATERIALS AND METHODS: One hundred fifty-four patients with stage I and II breast cancer were treated with conservative surgery plus radiotherapy between January 1992 and December 2002 at the Keimyung University Dongsan Medical Center. According to TNM stage, 93 patients were stage I, 50 were IIa, and 11 were IIb. The affected breasts were irradiated with 6 MV photons to 50.4 Gy in 28 fractions over 5.5 weeks with a boost irradiation dose of 10~16 Gy to the excision site. Chemotherapy was administered in 75 patients and hormonal therapy in 92 patients with tamoxifen. Follow-up periods were 13~179 months, with a median of 92.5 months. RESULTS: The 5- and 10-year overall survival rates were 97.3% and 94.5%, respectively. The 5- and 10-year disease-free survival (5YDFS and 10YDFS, respectively) rates were 92.5% and 88.9%, respectively; the ultimate 5YDFS and 10YDFS rates after salvage treatment were 93.9% and 90.2%, respectively. Based on multivariate analysis, only the interval between surgery and radiation therapy (< or = 6 weeks vs. >6 weeks, p=0.017) was a statistically significant prognostic factor for DFS. The major type of treatment failure was distant failure (78.5%) and the most common distant metastatic site was the lungs. The cosmetic results were good-to-excellent in 96 patients (80.7%). CONCLUSION: Conservative surgery and radiation for early stage invasive breast cancer yielded excellent survival and cosmetic results. Radiation therapy should be started as soon as possible after breast-conserving surgery in patients with early breast cancer, ideally within 6 weeks.
Breast ; Breast Neoplasms ; Cosmetics ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Lung ; Mastectomy, Segmental ; Multivariate Analysis ; Photons ; Survival Rate ; Tamoxifen ; Treatment Failure