• Radiation Oncology Journal
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• v.13 no.4
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• pp.321-330
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• 1995

Purpose : To evaluate whether the early pulmonary irradiation can prevent or decrease the pulmonary damage and contribute to improve ultimate survival in paraquat lung. Materials and Methods : From Jun. 1987 to Aug. 1993, thirty patients with paraquat poisoning were evaluated. Fourteen of these patients were received pulmonary irradiation(RT). All of the patients were managed with aggressive supportive treatment such as gastric lavage, forced diuresis, antioxidant agents and antifibrosis agents. Ingested amounts of paraquat were estimated into three groups(A : minimal 50cc). Pulmonary irradiation was started within 24 hours after admission(from day 1 to day 11 after ingestion of paraquat). Both whole lungs were irradiated with AP/PA parallel opposing fields using Co-60 teletherapy machine. A total of 10Gy(2Gy/fr. x 5days) was delivered without correction of lung density. Results : In group A, all patients were alive regardless of pulmonary irradiation and in group C, all of the patients were died due to multi-organ failure, especially pulmonary fibrosis regardless of pulmonary irradiation. However, in group B, six of 7 patients($86{\%}$) with no RT were died due to respiratory failure, but 4 of 8 patients with RT were alive and 4 of 5 patients who were received pulmonary irradiation within 4 days after ingestion of paraquat were all alive though radiological pulmonary change. One patient who refused RT after 2Gy died due to pulmonary fibrosis. All 3 patients who were received pulmonary irradiation after 4 days after ingestion were died due to pulmonary fibrosis in spite of recovery from renal and hepatic toxicity Conclusion : It is difficult to find out the effect of pulmonary irradiation on the course of the paraquat lung because the precise plasma and urine paraquat concentration were not available between control and irradiation groups. But early pulmonary irradiation within 4 days after paraquat poisoning with aggresive supportive treatment appears to decrease Pulmonary toxicity and contribute survival in patients with mouthful ingestion of paraquat who are destined to have reversible renal and hepatic damage but irreversible pulmonary toxicity.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.241-247
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• 1993

Between July 1988 and December 1992, we treated 45 patients who had deep seated inoperable or residual and/or recurrent intracranial tumors using LINAC based stereotactic radiosurgery at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. Treated intracranial tumors included pituitary tumors (n=15), acoustic neurinomas (n=8), meningiomas (n=7), gliomas (n=6), craniopharyngiomas (n=4), pinealomas (n=3), hemangioblastomas (n=2), and solitary metastatic tumor from lung cancer (n=1). The dimension of treatment field varied from 0.23 to 42.88 $cm^3\;(mean;\;7.26\;cm^3)$. The maximum tumor doses ranging from 5 to 35.5 Gy (mean; 29.9 Gy) were given, and depended on patients' age, target volume, location of lesion and previous history of irradiation. There were 22 male and 23 female patients. The age was varied from 5 to 74 years of age (a median age; 43 years). The mean duration of follow-up was 35 months (2~55 months). To date, 18 $(39.1\%)$ of 46 intracranial tumors treated with SRS showed absent or decrease of the tumor by serial follow-up CT and/or MRI and 16 $(34.8\%)$ were stationary, e.g. growth arrest. From the view point of the clinical aspects, 34 $(73.9\%)$ of 46 tumors were considered improved status, that is, alive with no evidence of active tumor and 8 $(17.4\%)$ of them were stable, alive with disease but no deterioration as compared with before SRS. Although there showed slight increase of the tumor in size according to follow-up imagings of 4 cases (pituitary tumor 1, acoustic neurinomas 2, pinealoma 1), they still represented clinically stable status. Clinically, two $(4.4\%)$ Patients who were anaplastic astrocytoma (n=1) and metastatic brain tumor (n=1) were worsened following SRS treatment. So far, no serious complications were found after treatment. The minor degree headache which could be relieved by steroid or analgesics and transient focal hair loss were observed in a few cases. There should be meticulous long term follow-up inall cases.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.287-296
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• 1997

Purpose : This is study of whether 3-D conformal radiotherapy for carcino-mas of the ethmoid sinus were better than those treated with conventional 2-D plan, Materials and Methods : The 3-D conformal treatment Plans were compared with conventional 2-D plans in 4 patients with malignancy of the ethmoid sinus. Isodose distribution, dose statistics, and dose volume histogram of the planning target volume were used to evaluate differences between 2-D and 3-D plans. In addition. the risk of radiation exposure of surrounding normal critical organs are evaluated by means of point dose calculation and dose volume histogram. Results : 3-D conformal treatment plans for each patient that the better tumor coverages by the planning target volume with improved dose homo-geneity, compared to 2-D conventional treatment Plans in the same Patient. On the other hand, the radiation dose distributions to the surrounding nor-mal tissue organs, such as the orbit and optic nerves are not significantly reduced with our technique, but a substantial sparing in the brain stem and optic chiasm for each patient. Conclusion : Our findings represented the potential advantage of 3-D treatment planning for dose homogeniety as well as sparing of the normal tissue surrounding the tumor. However, further investigational studies are required to define the clinical benefit.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.339-348
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• 1997

Purpose : To evaluate the role of postoperative radiation therapy after curative resection of sigmoid colon cancer Materials and Methods : From 1988 to 1993, a total of 93 Patients with curative resectable sigmoid colon cancer of modified Astler-Coiler (MAC) stage B2, B3, C2, C3 was divided into two groups on the basis of those who received radiation treatment and those who did not. Forty-three patients who treated by surgery alone were classified as postop RT (-) group The remaining 50 patients who underwent postoperative radiotherapy were classified as postop RT (+) group. In all patients in Postop RT (+) group. radiation therapy was delivered using 4 or 10 MV linear accelerators to treat the tumor bed with approximately 5cm margin to a total dose 50.4-61Gy(median 54Gy) in 1.8Gy per fraction. Thirty-two patients were treated. with 5-Fluorouracil based adjuvant chemotherapy at least 3 cycles. but these was no significant difference between two groups. Treatment failure Pattern, 5-year local failure-free survival rates (LFFS), and 5-year disease-free survival rates (DFS) were compared between two groups. Result : Five year LFFS and DFS were $85.1\%,\;68.5\%$, respectively, In Postop RT (-) group, LFFS was $76.2\%$ compared with $91.7\%$ in Postop RT (+) group. Improved LFFS and DFS were seen for patients with stage C3 sigmoid colon carcinoma with postoperative radiation therapy compared with postop RT (-) group (P=0.01, p=0.06 respectively), in stage B3, LFFS washigher in postop RT (+) group than that in Postop RT (-) group. although itwas not significant. Especially, local control was higher in stage 74 inpostop RT (+) group than that in postop RT (-) group, Conclusion : This studv showed significantly improved LFFS and DFS in MAC Stage C3 and improved tendency of LFFS and DFS in MAC Stage B3 disease. Large scale prospective study is required to verify the role of adjuvant radiation therapy in resectable sigmoid colon cancer.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.249-258
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• 1993

Between March 1983 and December 1989, ninety-six patients with intracranial glioma were treated in the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. We retrospectively reviewed each case to evaluate variable factors influencing the treatment results and to develop an optimal therapy Policy. Median follow-up is 57 months (range: 31~133 months). Of the 96 patients, 60 $(63\%)$ were males and 36 $(37\%)$ were females. Ages ranged from 3 to 69 years (median 42 years). The most common presenting symtoms were headeche $(67\%)$ followed by cerebral motor and sensory discrepancy $(54\%),$ nausea and vomiting $(34\%),$ seizure $(19\%),$ mental change $(10\%)$ and memory and calculation impairment $(8\%).$ Eighty five $(88.5\%)$ patients all, except 11 $(11.5\%)$ brain stem lesions, were biopsy proven intracranial glioma. The distribution by histologic type was 64 astrocytomas $(75\%),$ 4 mixed oligoastrocytomas $(5\%),$ and 17 oligodendrogliomas $(20\%).$ Fourty nine patients $(58\%$ were grade I, II histology and 36 $(42\%)$ patients were grade III, IV histology. Of the 96 patients, 64 $(67\%)$ recieved postoperative RT and 32 $(33\%)$ were treated with primary radiotherapy. Gross total resection was peformed in 14 $(16\%)$ patients, subtotal resection En 29 $(34\%),$ partial resection in 21 $(25\%),$ and biopsy only in 21 $(25\%).$ Median survival time was 53 months (range 2~ 133 months), and 2- and, 5-year survival rate were $69\%,49\%$ respectively. 5-year survival rate by histologic grade was grade I, $70\%,$ grade II, $58\%,$ grade III, $28\%,$ and grade IV, $15\%.$ Multivariated analysis demonstrate that age at diagnosis (p=0.0121), Karnofsky performance Status (KPS) (p=0.0002), histologic grade (p=0.0001), postoperative radiation therapy (p=0.0278), surgical extent (p =0.024), cerebellar location of tumor (p=0.0095) were significant prognostic factors influencing on survival.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.91-98
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• 1998

Purpose : The relationship between environmental PH on the radiation induced-apoptosis in SCK mammary adenocarcinoma cells and cell cycle dependence was investigated. Material and Methods : Mammary adenocarcinoma cells of A/J mice(SCK cells) in exponential growth phase were irradiated with a $l37^Cs$ irradiator at room temperature. The cells were irradiated 1 hour after the media was replaced with fresh media at a different pHs. After incubation at $37^{\circ}C$ for 0-48 h, the extent of apoptosis was determined using agarose gel electrophoresis and flow cytometry. The progression of cells through the cell cycle after irradiation in different pHs was also determined with flow cytometry. Bssults : The induction of apoptosis by irradiation in pH 6.6 medium was markedly less than that in pH 7.5 medium. When the cells were irradiated and maintained in pH 7.5 medium, the percentage of cells in $G_2/M$ phase rapidly increased to about $70\%$ at 12 h after an exposure to 120y and returned to control level by 36 h. The percentage of cells in G1 phase decreased as the percentage of cells in $G_2/M$ increased. On the other hand, in pH 6.6 medium the percentage of cells in G2/M phases gradually increased to about $45\%$ at 24 h after 12Gy irradiation and then slowly recessed and consequently, as much as $30-35\%$ of the cells were still in the Ga/M phase 48 h after irradiation. The percentage of cells in G1 phase then increased as the Ga/M arrest began to recede. The radiation-induced Ga/M arrest in PH 0.0 medium lasted markedly longer than that in pH 7.5 medium. Conclusion : Radiation-induced apoptosis in SCK tumor cells are reversely suppressed in an acidic environment. Radiation-induced Ga/M arrest is prolonged in an acidic environment indicating that the suppression of radiation-induced apoptosis and prolongation of radiation-induced Ga/M arrest in an acidic environment are related.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.238-248
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• 1999

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.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.195-202
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• 1998

Purpose : In order to obtain basic data for treatment plan in radiosurgery, we measured small fields of 6 MV X-rays and compared the measured data with our Monte Carlo simulations for the small fields. Materials and Methods : The small fields of 1.0, 2.0 and 3.0 cm in diameter were used in this study. Percentage depth dose (PDD) and beam Profiles of those fields were measured and calculated. A small semiconductor detector, water phantoms, and a remote control system were used for the measurement Monte Carlo simulations were Performed using the EGS4 code with the input data prepared for the energy distribution of 6 MV X-rays, beam divergence, circular fields and the geometry of the water phantoms. Results : In the case of PDD values, the calculated values were lower than the measured values for all fields and depths, with the differences being 0.3 to 5.7% at the depths of 20 to 20.0 cm and 0.0 to 8.9% at the surface regions. As a result of the analysis of beam profiles for all field sizes at a depth of loom in water phantom, the measured 90% dose widths were in good agreement with the calculated values, however, the calculated Penumbra radii were 0.1 cm shorter than measured values. Conclusion : The measured PDDs and beam profiles agreement with the Monte Carlo calculations approximately. However, it is different when it comes to calculations in the area of phantom surface and penumbra because the Monte Carlo calculations were performed under the simplified geometries. Therefore, we have to study how to include the actual geometries and more precise data for the field area in Monte Carlo calculations. The Monte Carlo calculations will be used as a useful tool for the very complicated conditions in measurement and verification.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.167-175
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• 1998

Purpose : It is not a simple task to achieve the ideal isodose curve with a standard vaginal applicator or sing1e plane needle impant in the paravaginal tissue when primary or recurrent gynecological neoplasms(cervical cancers, vaginal cancers and vulvar cancers) are treated as a boost following external beam radiotherapy. The authors introduce the development and construction of a simple, inexpensive, customized applicator for volume implant to maximize the radiation dose to the tumor while minimizing the dose to the rectum and the bladder. Materials and Methods : Nine patients underwent Ir-192 transperineal interstitial implantation for either recurrent(5 cases) or primary(3 cases) cervical cancers or primary vaginal cancer(1 case) between August 1994 and February 1998 at Ajou university hospital. First 3 cases were performed with a sing1e plane implant guided by digital palpation. Because of inadequate isodose coverage in the tumor volume in first 3 cases, we designed and constructed interstitial vaginal applicator for volume implant to improve tumor dose distribution and homogeneity while sparing the surrounding normal tissue. Our applicators consist of vaginal obturator and perineal template that made of the clear acrylamide and dental mold material$(Provil^{(R)})$. The applicators were customized individually according to the tumor size and its location Both HDR and LDR irradiation were given with these applicators accomodating 6 Fr needles(Microselectron Nucletron). The pretreatment planning prior to actual implant was performed whenever possible. Results : Needles can be inserted easily and evenly into the tumor volume through the holes of templates, requiring less efforts and time for the implant procedure. Our applicators made of materials available from commercial vendors. These have an advantage that require easy procedure, and spend relatively short time to construct. Also it was possible to fabricate applicators to individualize according to the tumor size and its location and to achieve the ideal isodose coverage. We found an accurate needle arrangement and ideal dose distribution through the CT scan that was obtained in 3 cases after needle implant. Three patients with primary cervical and vaginal cancers were controlled locally at final follow up. But all recurrent cases failed to do so. Conclusion : The authors introduce inexpensive, simple interstitial vaginal templates which were self-designed and constructed using materials available from commercial vendors such as acrylanide and dental mold material $(Provil^{(R)})$.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.187-194
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• 1999

Purpose : The aim of this study is to look for the possible efficacy of external irradiation for locally advanced papillary thyroid cancers (stage pT4 or Nl ). Methods and Materials : From August 1981 through September 1997, 91 Patients with locally advanced papillary thyroid cancers (stage pT4 or Nl ) have been treated with external irradiation and followed up at our clinic. All of the patients have been treated with surgical resection. After surgery, 23 patients received postoperative external irradiation with or without ablative radioiodine therapy, whereas the other 68 patients were treated with ablative radioiodine therapy alone. Distributions of sex, age, and stage were comparable in both irradiated and nonirradiated groups. Multivariate analysis of the influence by age, sex, stage, ablative radioiodine therapy and external irradiation on local control were peformed by using Cox's proportional hazard model. Results : Overall survival rates at 7 years were of no significant difference in both groups. There were $98.1\%$ for no RT group and $90\%$ for RT group (p=0.506). 5-year local control rates were significantly different, these were $95.2\%$ for RT group and $67.5\%$ for no RT group (p=0.0408). An analysis of the prognostic factors, age, sex, stage, and RAI were not significant variables, except for the external irradiation. Conclusion : Adjuvant postoperative external irradiation did not affect overall survival, but significantly improved local control in the patients with locally advanced papillary thyroid cancers (stage pT4 or lympy node involvement).