Estimation of Inhomogeneity Correction Factor in Small Field Dosimetry / 의학물리

In this study, we estimated inhomogeneity correction factor in small field. And, we evaluated accuracy of treatment planning and measurement data which applied inhomogeneity correction factor or not. We developed the Inhomogeneity Correction Phantom (ICP) for insertion of inhomogeneity materials. The inhomogeneity materials were 12 types in each different electron density. This phantom is able to adapt the EBT film and 0.125 cc ion chamber for measurement of dose distribution and point dose. We evaluated comparison of planning and measurement data using ICP. When we applied to inhomogeneity correction factor or not, the average difference was 1.63% and 10.05% in each plan and film measurement data. And, the average difference of dose distribution was 10.09% in each measurement film. And the average difference of point dose was 0.43% and 2.09% in each plan and measurement data. In conclusion, if we did not apply the inhomogeneity correction factor in small field, it shows more great difference in measurement data. The planning system using this study shows good result for correction of inhomogeneity materials. In radiosurgery using small field, we should be correct the inhomogeneity correction factor, more exactly.

Estimation of CyberKnife Respiratory Tracking System Using Moving Phantom / 의학물리

In this study, we evaluated accuracy and usefulness of CyberKnife Respiratory Tracking System (SynchronyTM, Accuray, USA) about a moving during stereotactic radiosurgery. For this study, we used moving phantom that can move the target. We also used Respiratory Tracking System called Synchrony of the Cyberknife in order to track the moving target. For treatment planning of the moving target, we obtained an image using 4D-CT. To measure dose distribution and point dose at the moving target, ion chamber (0.62 cc) and gafchromic EBT film were used. We compared dose distribution (80% isodose line of prescription dose) of static target to that of moving target in order to evaluate the accuracy of Respiratory Tracking System. We also measured the point dose at the target. The mean difference of synchronization for TLS (target localization system) and Synchrony were 11.5+/-3.09 mm for desynchronization and 0.14+/-0.08 mm for synchronization. The mean difference between static target plan and moving target plan using 4D CT images was 0.18+/-0.06 mm. And, the accuracy of Respiratory Tracking System was less 1 mm. Estimation of usefulness in Respiratory Tracking System was 17.39+/-0.14 mm for inactivity and 1.37+/-0.11 mm for activity. The mean difference of absolute dose was 0.68+/-0.38% in static target and 1.31+/-0.81% in moving target. As a conclusion, when we treat about the moving target, we consider that it is important to use 4D-CT and the Respiratory Tracking System. In this study, we confirmed the accuracy and usefulness of Respiratory Tracking System in the Cyberknife.

Early Therapeutic Effects of Cyberknife Radiosurgery on Trigeminal Neuralgia / 대한방사선종양학회지

PURPOSE: We evaluated whether Cyberknife radiosurgery is an effective and safe method of therapy for medically intractable trigeminal neuralgia (TN). MATERIALS AND METHODS: We retrospectively analyzed the outcome of 26 patients, who failed to surgery or were not suitable candidates for invasive intervention and were treated by Cyberknife radiosurgery between March 2004 and May 2005. Radiosurgery doses of 60~64 Gy were delivered to the 80% isodose line prescribed to an 6 mm length of the nerve, sparing the most proximal 3 mm away from the trigeminal nerve root entry zone (median dose: 64 Gy). RESULTS: Follow-up period was 3~15 months (median follow-up period: 9 months) Preliminary results from a cohort of 26 patients undergoing Cyberknife radiosurgery for TN showed that pain relief was achieved in 50% (13/26) of patients within the first 24 hrs after treatment. At last follow-up, 96.2% (25/26) of patients reported early pain relief within 7 days. Treatment failure developed in 2 of 26. Poor response occurred in one patient and relapse was observed in the other patient. 3 patients had hypoesthesia (11.5%), which was the only complication observed with any of our patients. CONCLUSION: With these results, authors assumed that Cyberknife radiosurgery for TN could be one of safe and effective therapeutic methods.

The Development of Quality Assurance Program for CyberKnife / 대한방사선종양학회지

PURPOSE: Standardization quality assurance (QA) program of CyberKnife for suitable circumstances in Korea has not been established. In this research, we investigated the development of QA program for CyberKnife and evaluation of the feasibility under applications. MATERIALS AND METHODS: Considering the feature of constitution for systems and the therapeutic methodology of CyberKnife, the list of quality control (QC) was established and divided dependent on the each period of operations. And then all these developed QC lists were categorized into three groups such as basic QC, delivery specific QC, and patient specific QC based on the each purpose of QA. In order to verify the validity of the established QA program, this QC lists was applied to two CyberKnife centers. The acceptable tolerance was based on the undertaking inspection list from the CyberKnife manufacturer and the QC results during last three years of two CyberKnife centers in Korea. The acquired measurement results were evaluated for the analysis of the current QA status and the verification of the propriety for the developed QA program. RESULTS: The current QA status of two CyberKnife centers was evaluated from the accuracy of all measurements in relation with application of the established QA program. Each measurement result was verified having a good agreement within the acceptable tolerance limit of the developed QA program. CONCLUSION: It is considered that the developed QA program in this research could be established the standardization of QC methods for CyberKnife and confirmed the accuracy and stability for the image-guided stereotactic radiotherapy.

The Change of Transforming Growth Factor beta1 (TGF-beta1) Expression by Melatonin in Irradiated Lung / 대한방사선종양학회지

PURPOSE: The changed expressions of TGF-beta1, as a key cytokine in the fibrotic process, due to melatonin with potent antioxidative effects, were investigated in the irradiated lung using fibrosis-sensitive C57BL/6 mice. MATERIALS AND METHODS: Female C57BL/6 mice were divided into control irradiation-only, and melatonin (300 mg/kg i.p. 1 hr before irradiation) pretreatment groups. The thoraces of the mice were irradiated with a single dose of 12 Gy. The mRNA expressions of TGF-beta1 in the lung tissue 2 and 4 weeks after irradiation were quantified using semiquantitive RT-PCR, and the cellular origin and expression levels of TGF-beta1 protein were identified using immunohistochemical staining. RESULTS: The relative mRNA expression levels in the irradiation-only and melatonin pretreatment groups 2 and 4 weeks after irradiation were 1.92- and 1.80-fold (p=0.064) and 2.38- and 1.94-fold (p=0.004) increased, respectively compared to those in the control group. Increased expressions of TGF-beta1 protein were prominently detected in regions of histopathological radiation injury, with alveolar macrophages and septal epithelial cells serving as important sources of TGF-beta1 expression. At 2 and 4 weeks after irradiation, the expression levels of protein were 15.8% vs. 16.9% (p=0.565) and 36.1% vs. 25.7% (p=0.009), respectively. CONCLUSION: The mRNA and protein expressions of TGF-beta1 in the lung tissue following thoracic irradiation with 12 Gy were significantly decreased by melatonin pretreatment at 4 weeks. These results indicate that melatonin may have a possible application as an antifibrotic agent in radiation-induced lung injury.

The Change of Transforming Growth Factor beta1 (TGF-beta1) Expression by Melatonin in Irradiated Lung / 대한방사선종양학회지

PURPOSE: The changed expressions of TGF-beta1, as a key cytokine in the fibrotic process, due to melatonin with potent antioxidative effects, were investigated in the irradiated lung using fibrosis-sensitive C57BL/6 mice. MATERIALS AND METHODS: Female C57BL/6 mice were divided into control irradiation-only, and melatonin (300 mg/kg i.p. 1 hr before irradiation) pretreatment groups. The thoraces of the mice were irradiated with a single dose of 12 Gy. The mRNA expressions of TGF-beta1 in the lung tissue 2 and 4 weeks after irradiation were quantified using semiquantitive RT-PCR, and the cellular origin and expression levels of TGF-beta1 protein were identified using immunohistochemical staining. RESULTS: The relative mRNA expression levels in the irradiation-only and melatonin pretreatment groups 2 and 4 weeks after irradiation were 1.92- and 1.80-fold (p=0.064) and 2.38- and 1.94-fold (p=0.004) increased, respectively compared to those in the control group. Increased expressions of TGF-beta1 protein were prominently detected in regions of histopathological radiation injury, with alveolar macrophages and septal epithelial cells serving as important sources of TGF-beta1 expression. At 2 and 4 weeks after irradiation, the expression levels of protein were 15.8% vs. 16.9% (p=0.565) and 36.1% vs. 25.7% (p=0.009), respectively. CONCLUSION: The mRNA and protein expressions of TGF-beta1 in the lung tissue following thoracic irradiation with 12 Gy were significantly decreased by melatonin pretreatment at 4 weeks. These results indicate that melatonin may have a possible application as an antifibrotic agent in radiation-induced lung injury.

Development of Total Body Irradiation Program / 의학물리

In total body irradiation (TBI) for leukemia, we have a two methode. One is a AP (anterior-posterior) method and the other is a Lateral methode. Our hospital used lateral methode. TBI must consider about body contour, because of homogeneous dose distribution. For compensation about irregular body contour, we use compensator. For TBI treatment, we must be considered, accurate manufacture of compensator and accurate calculation of dose. We developed the automatic program for TBI. This program accomplished for compensator design and dose calculation for irregular body. This program was developed for uses to use in a windows environment using the IDL language. In this program, it use energy data for each energy: TMR, output factor, inverse square law, spoiler, field size factor. This program reduces the error to happen due to the manual. As a development of program, we could decrease the time of treatment plan and care the patient accurately.

Breast Conservation Therapy Versus Mastectomy - Preliminary Results of Pattern of Failure and Survival Rate in Early Breast Cancer / 대한방사선종양학회지

PURPOSE: This retrospective study was conducted to compare early preliminary results of breast conservation therapy (BCT) with mastectomy in early breast cancer. MATERIALS AND MEHTODS: We evaluated 171 women with AJCC stage I and II breast cancer who had been treated at Kangnam St. Mary's Hospital from March 1989 to August 1996. Eighty-eight patients underwent mastectomy and 85 patients did conservative surgery with breast irradiation. In the BCT group, all patients received whole breast irradiation to a total dose of 45~50 Gy/5~6 wks, followed by a boost to the original tumor site at least 60 Gy. Chemotherapy was administered to 29 (34.1%) patients in BCT and 40 (45.5%) in mastectomy, with various sequencing of surgery and/or radiation. We compared survival rate, patterns of failure in each treatment group and the prognostic factors that had a significant effect on treatment failure. The median follow-up time was 63 months (19~111 months). Log rank test was used to estimate the prognostic factors for treatment failure. RESULTS: Overall survival, disease free survival, locoregional recurrence and distant metastasis rates were not significantly different between the two treatment groups. During the follow-up period, 11 patients (12.5%) in the mastectomy group and 10 patients (11.8%) in the BCT group were failed. Six local recurrences occurred after mastectomy and 5 after BCT. Five patients failed at distant site in mastectomy and 4 in BCT. Of the local recurrence cases, five of 6 mastectomy patients and 3 of 5 BCT patients were alive with no evidence of disease after salvage surgery and/or chemoirradiation. Our results indicated that the major influence on survival was distant metastasis. Unfortunately, control of distant metastasisis was not frequently achieved. Even with salvage systemic therapy or radiotherapy, most of distant metastasis patients died or had uncontrolled disease in both treatment groups: only one of 4 BCT patients and none of mastectomy patients were alive without disease. There was no apparent difference in the incidence rate of contralateral breast cancer and non-breast 2nd primary tumor between the two treatment groups. Univariate Log-rank test identified the N stage and the involved axillary LN number as distinct prognostic factors that were highly predictive of treatment failure in both treatment groups. Additionally, marginal status in BCT and histologic nuclear grade in the mastectomy group were risk factors for treatment failure (p<0.05). CONCLUSION: Although further careful follow-up is necessary to confirm the trends evident in this series, it would appear that patterns of failure and survival rate following conservative surgery and radiotherapy in early breast cancer are similar to those following mastectomy. The great majority of patients with local recurrence had an exellent salvage rate in both treatment groups. Therefore, these preliminary short term results support BCT as an equally effective management for early breast cancer as an alternative to mastectomy.

The Effect of More Aggressive Surgery in Esophageal Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: One of the most controversial aspects of surgery for esophageal cancer is the appropriate extent of lymphadenectomy to achieve the best outcome. The purpose of this study was to clarify the effects of an extended lymphadenectomy (complete 2-field lymphadenectomy; complete 2-FL or 3-field lymphadenectomy; 3-FL) in esophageal cancer surgery. MATERIALS AND METHODS: In order to prevent a local recurrence and improve the long-term survival following surgery, an extended lymphadenectomy has systematically been performed at four hospitals of the Catholic University College of Medicine since 1995. And since that time, until the end of 2001, a total of 98 patients have undergone the procedure. Their clinical results were compared with those of 54 esophageal cancer patients who received an incomplete 2-field lymphadenectomy (incomplete 2-FL), between 1990 and 1994, at the same hospitals. RESULTS: After an extended lymphadenectomy a recurrence was noted in 41 cases (44.6%), a local recurrence occurred in 23 cases (25.0%) and a metastatic recurrence in 18 (19.6%), with the 5-year survival rate improved to 39.5%, than the 29% of the incomplete 2-FL. There was no difference in the morbidity of the fatal complications and the mortality between the two groups. CONCLUSION: The long survival rate was improved with an extended lymphadenectomy, but the morbidity and mortality rate had not increased.

Effect of Cytarabine, Melphalan, and Total Body Irradiation as Conditioning for Autologous Stem Cell Transplantation for Patients with AML in First Remission / 대한방사선종양학회지

PURPOSE: Current results of autologous stem cell transplantation (SCT) suggest that this procedure may prolong disease free survival in patients with acute myeloid leukemia (AML). Autologous SCT is increasingly used as treatment for AML in first remission. The aim of this study was to evaluate the outcome of autologous SCT for patients with AML in first remission treated by autologous SCT using cytarabine, melphalan and total body irradiation (TBI) as the conditioning regimen. MATERIALS AND METHODS: Between January 1995 and December 1999, 29 patients with AML in first remission underwent autologous SCT. The median age of patients was 33 years (range, 16 to 47). The conditioning regimen consisted of cytarabine (3.0 gm/m2 for 3 days), melphalan (100 mg/m2 for 1 day) and TBI (total 1000 cGy in five fractions over 3 days). RESULTS: The median follow up was 40 months with a range of 3 to 58 months. The 4-year cumulative probability of disease free survival was 69.0%, and median survival was 41.5 months. The 4-year relapse rate was 27.6%. The factor influencing disease free survival and relapse rate was the French-American-British (FAB) classification (M3 group vs. other groups; p=0.048, p=0.043). One patient died from treatment-related toxicity. CONCLUSION: Although the small number of patients does not allow us to draw any firm conclusion, our results were encouraging and suggest that the association of cytarabine, melphalan and TBI as a conditioning regimen for autologous SCT for AML in first remission appears to be safe and effective.

Effects of Preoperative Radiotherapy for T2, T3 Distal Rectal Cancer / 대한방사선종양학회지

PURPOSE: Preoperative radiotherapy has been used to induce tumor regression and allow complete resection of rectal cancer with a sphincter preservation surgery. This study was performed to determine the effectiveness of preoperative radiotherapy for T2, T3 distal rectal carcinoma. MATERIALS AND METHODS: From November 1995 to June 1997, fifteen patients with invasive distal rectal cancer were treated with preoperative radiotherapy followed by sphincter preservation surgery. Classification by preoperative T stage consisted of 7 T2 and 8 T3 tumors. Radiation therapy was delivered with 6 MV and 15 MV linear accelerator, at 1.8 Gy fractions for 5 days per week. Total radiation doses were 45 Gy to 50.4 Gy (median : 50.4 Gy). Sphincter preservation surgery was performed 4~6 weeks after the completion of radiotherapy. Median follow-up was 22 months (range : 16~37 months). RESULTS: One patient (6.7%) had a complete pathologic response. Comparing the stage at the diagnostic workup with the pathologic stage, tumor downstaging of T stages occurred in 11 of 15 patients (73.3%) and N1 stages occurred in 2 of 5 patients (40%). No patient developed progressive disease undergoing treatment. Two patients suffered local recurrence at 7 and 20 months, and one a distant metastasis at 30 months. No grade 3 or 4 toxicity was observed. CONCLUSION: Our experience suggests that preoperative radiotherapy followed by sphincter preservation surgery is well tolerated, and can significantly reduce the tumor burden for T2, T3 distal rectal cancer.

Preliminary Result in Patients with Primary Hepatoma Treated by Stereotactic Radiotherapy / 대한방사선종양학회지

PURPOSE: It is not common to evaluate the response of the fractionated stereotactic radiotherapy (SRT) to primary hepatoma as compared with conventional radiotherapy. The purpose of the study was to take the preliminary result on the clinical trial of primary hepatoma by SRT. MATERIALS AND METHODS: From July 1999 to March 2000, thirty three patients were hospitalized in the St. Mary's Hospital, and treated with SRT for extracranial tumors. Among them, 13 patients were diagnosed to primary hepatoma and then applied by frameless SRT using 6 MV linac accelerator. There were 12 male and 1 female patients. They had the age of 44~66 year old (median : 59) and the tumor size of 10~825 cc (median : 185 cc). SRT was given to them 3~5 fractions a week (5 Gy/fraction, 90% isodose line) for 2~3 weeks. Median dose of SRT was 50 Gy and the range was 30~50 Gy. RESULTS: Follow-up period ranged from 3 months to 13 months with median of 8 months. After treating SRT to thirteen patients with primary hepatoma, the response of the tumor was examined by abdominal CT : they are classified by 1 complete regression (7.7%), 7 partial regression (53.8%), 4 minimal regression (30.8%), 1 stable disease (7.7%). The positive responses more than partial remission were 8 patients (61.5%) after the treatment. The level of serum alpha-fetoprotein (AFP) after the treatment as compared with pretreatment had been 92.3% decreased. There was no severe complication except dyspepsia 84.6%, mild nausea 69.2%, transient decreased of hepatic function 15.4% and fever 7.7%. CONCLUSION: SRT to the patients with primary hepatoma was potentially suggested to become the safe and more effective tool than the conventional radiotherapy even though there were relatively short duration of follow-up and small numbers to be tested.

Total Body Irradiation for Myasthenia Gravis with Thymoma: Case Report / 대한방사선종양학회지

Myasthenia gravis (MG) is relatively rare occuring as one of important autoimmune disease to affect neuromuscular junction. This study was clinically to evaluate total body irradiation (TBI) against two patients including 33-year and 39-year females for chronic MG with thymoma who hospitalized in the St. Mary's Hospital, Catholic University since 1994 as well as who showed no response by thymectomy, immunotherapy and hormonal therapy. TBI designed by the dose of 150~180 cGy consisting of 10 cGy per fraction, three times a week, for 5~6 weeks using linear accelerator of 6 MV. During the treatment of TBI, they did complain acute side effect such as vomiting and also appear improved physical condition from 4~6 weeks after TBI. Through the follow-up period of 18 or 42 months after TBI, they did not have any symptomatic recurrence. Consequently, the results suggest that TBI can be used as an alternative tool for the patients concurrently for MG with thymoma who had been refractory to various conventional therapies like thymectomy, immunotherapy and hormonal therapy.

Thermoradiotherapy in the Treatment of Advanced Stomach Cancer: To compare the difference between the results of pre- and post-radiotherapy hyperthermia / 대한방사선종양학회지

PURPOSE: To improve the therapeutic results of postoperative recurrent disease and inoperable disease of stomach cancer, we used the thermoradiotherapy. We conducted a retrospective analysis of the results and compared between the results of hyperthermia before radiotherapy and those of hyperthermia after radiotherapy. MATERIALS AND METHODS: From july 1994 to november 1996, we treated twenty patients of locally advanced stomach cancer and recurrent stomach cancer with thermoradiotherapy. We divided those patients into two groups : hyperthermia before radiotherapy group (PreRT group : 13 patients) and hyperthermia after radiotherapy group (PostRT group : 7 patients). We performed radiation therapy to the total tumor dose of 3000-5040cGy in fraction of 180-300cGy and 5 fractions per week. Hyperthermia was performed with 8 MHz radiofrequency apparatus. We treated those patients everyday for thirty minutes within ten minutes before radiation therapy in PreRT group, and 1-2 sessions per week for 40-60 minutes within ten minutes after radiation therapy in PostRT group. RESULTS: Overall response rate was 33.3%. This response rate was appeared same in both groups. Mean survival and 1 year survival rate were 10.3 months and 16.5%. In PreRT group, mean survival and 1 year survival rate were 6.8 months and 9.0%, and in PostRT group, mean survival and 1 year survival rate were 7.7 months and 34%. There were no statistical significant difference between the prognostic factors and therapeutic results. CONCLUSION: The thermoradiotherapy was safe treatment method in advanced and recurrent gastric cancer when compared with other treatment. Because the number of patients we treated was small and the follow up period was short, we were not able to draw any conclusions about therapeutic efficacy of sequence of radiation therapy and hyperthermia Therefore, further clinical trial of thermoradiotherapy for stomach cancer appear to be warranted.

Effects of Adjuvant Radiation Therapy and Chemotherapy Following Curative Surgery in Locally Advanced Rectal Cancer / 대한치료방사선과학회지

PURPOSE: To evaluate the effect of postoperative adjuvant radiation therapy and chemotherapy on the survival, pattern of failure and complication for locally advanced rectal carcinoma MATERIALS AND METHODS: From October 1992 to September 1995, twenty eight patients with rectal carcinoma were treated by postoperative adjuvant radiation therapy and chemotherapy. Radiation therapy was delivered with 6MV and 15MV linear accelerator, 180cGy fractions 5 day per week. Total radiation doses were 5040cGy in B2+3 and 5580cGy in C2+3. Within 4 weeks after radical surgery, 5-FU(400mg/m2/day) and Leucovorin(20mg/m2/day) were administered by intravenous injection for 4 days during the first and fifth week of radiation therapy. The median follow up was 19 months with a range 2 to 47 months. RESULTS: The 2 year overall survival and disease free survival rates were 78.6% and 70.8%, respectively. The 2 year overall survival was 93.0% in B2+3 and 76.2% in C2+3(p=0.11). The 2 year disease free survival was 79.4% in B2+3 and 69.2% in C2+3(p=0.13). The overall failure rate was 21.4%(6/28) including 10.7%(3/28) locoregional recurrence, 3.6%(1/28) distant metastasis and 7.1%(2/28) locoregional recurrence with distant metastasis. The overall locoregional recurrence rate was 17.9%(5/28). The 2 year locoregional recurrence rates were 13.3%(2/15) and 23.1%(3/13) for respectively for B2+3 and C2+3. The difference between the locoregional recurrence of B2+3 and C2+3 patients was not significant(p=0.07). Complications developed in 13 patients(46.4%), including 8 dermatitis, 7 loose stool, 6 leukopenia, 4 tenesmus, 2 diarrhea. In Univariate analysis, there was no statistically significant factor except for tumor grade in locoregional recurrence, disease free survival and overall survival rate(p=0.04, 0.05, 0.04). CONCLUSION: This study suggests that postoperative adjuvant radiation therapy and chemotherapy is effective in patients with locally advanced rectal cancer. Therefore these results need to be confirmed with a long term follow-up and larger number of patients with the further clinical trials including prospective controlled studies.

Effects of Postoperative Radiation Therapy for Prevention of Keloids and Hypertrophic Scars / 대한치료방사선과학회지

PURPOSE: To evaluate the effects of surgical excision followed by radiation therapy for prevention of keloids and hypertrophic scars. MATERIALS AND METHODS: From October 1987 to April 1995, radiation therapy was applied to 167 sites in 106 patients with surgical excision in an attempt to prevention of recurrence against keloids and hypertrophic scars. The main etiology of the keloids and hypertrophic scars were surgery in 49.2%, trauma in 25.0%, ear-piercing in 5.4%, and burn in 5.4%. The patients' ages ranged from 3 to 70 years with a median of 32 years. Radiation therapy used ranged from 6 to 8MeV electron beam. Radiation therapy was delivered within 24 hours of surgical excision. Several dose schedules were used, varing from 400cGy in 1 daily fraction to 1900cGy in 4 daily fractions. The average total dose was 1059cGy, and the average dose per fraction was 433cGy. All patients were followed up from 24 to 114 months with a median follow up of 49 months. RESULTS: The overall recurrence rate was 12.6% (21/167). The overall 1-year and 2-year recurrence rates were 10.2% and 11.4%, respectively. Among 21 recurrent sites, seventeen sites (81%) were confirmed within 12 months after surgical excision. Period to recurrence ranged from 1 month to 47 months with a median recurrence time of 9.6 months. The history of previous therapy was only a significant factor in recurrence. Twenty-four patients had history of previous therapy, recurrence rates was significantly higher in this group than those without history of previous therapy (22.6% vs. 11.0%, P=0.04). There was no serious complication related to radiation therapy. CONCLUSION: This study suggests that surgical excision followed by radiation therapy is an effective method of preventing keloids and hypertrophic scars.

Minimal Change Nephrotic Syndrome Associated with Intraabdominal Liposarcoma / 대한신장학회잡지

We present a case of liposarcoma related with minimal change nephrotic syndrome. A 49-year-old woman was admitted due to generalized edema and a palpable mass at epigastric area. Her laboratory data were as follows : serum creatinine 0.6mg/dl, BUN 7mg/dl, serum total protein 3.6g/dl(albumin 0.6 g/dl) serum total cholesterol 299mg/dl, 24 hour-urine protein 5.1g. A CT scan of the abdomen revealed huge adult head sized mass(15X10X15cm) consisted with mixed pattern of well enhancing solid, cystic and fat portion which is located between the liver and the stomach. A kidney biopsy showed minimal change nephropathy. At explo-laparostomy the tumor was well differentiated liposarcoma. After operation and steroid therapy, her proteinuria and hypoalbuminemia were a little improved. And then radiation therapy(daily 180 cGy, 5 fx/wk, upto 5040cGy/28 fx/42 day) was done. Complete remission of liposarcoma was followed by regression of the nephrotic syndrome. After radiation therapy, her laboratory data were serum total protein 6.7g/dl (albumin 4.3g/dl), total cholesterol 170mg/dl, 24 hour-urine protein 0.3g. She has been maintained complete remission of the nephrotic syndrome by steroid maintenance dose.

Thermoradiotherapy in the Treatment of Locally Advanced Nonsmall Cell Lung Cancer / 대한치료방사선과학회지

PURPOSE: To improve the treatment results of locally advanced nonsmallcell lung cancer (NSCLC) patient, we treated those paients with regional hyperthermia combined with radiotherapy. And we conducted a retrospective analysis of the results. METHODS AND MATERIALS: Thirty two nonsmall cell lung cancer patients treated at the Department of Radiation Oncology, St. Mary's hospital. Catholic University Medical College were the base of this analysis. Fourteen patients of above them were treated with hyperthermia and radiotherapy of more than 3000 cGy in radiation dose. Radiofrequency capacitive hyperthermia was administered twice weekly, immediately after radiotherapy. Total sessions of hyperthermia ranged from 3 to 13 times (mean 7,8). Eighteen patient received an external radiation therapy alone. Median radiation dose was 5580 cGy (range, 3000-7000 cGy) in fraction of 180-300 cGy, 5 fractions per week. RESULTS: The results of themoradiotherapy group (HTRT group) were compared with radiation alone group (RT group). There were no complete response (CR) and 12 partial responses (PR) (CR rate 0%, response rate 85.7%) in HTRT group, whereas there were 2 CRs, 8 PRs and 8 no responses (CR rate 11.1%, response rate 55.6%) in RT group. There was significant differece in local response rate of the tumors between RT group and HTRT group (p<0.05). Overall 2 year survival rate and mean survival were 7.1% and 10.5 months for HTRT group, and 0% 8.1 months for RT group. However, by the number of hyperthermia, in cases with more than or equal to 10 sessions of hyperthermia, there were significant improvement in 2 year survival rate and mean survival (40.0% and 18.2 months) compared with those in cases with less than 10 sessions of hyperhtemia (7.4% and 7.4 months) (p<0.05). CONCLUSION: Thermoradiotherapy in locally advanced NSCLC patients increased their response rate but not 2 year survival and mean survival, therefore thermoradiotherpy with enough number of hyperthermia is suggested that may be one of the effective palliative treatments of those patients. And in cases with more than 10 sessions of hyperthermai, there showed improved 2 year survival rate and mean survival. But the number of the cases was small, further study in this aspect is required.

Effect of Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) on Neutropenia Occuring during Radiotherapy / 대한치료방사선과학회지

PURPOSE: To assess the efficacy of recombinant human granulocyte-macrophage colony-stimulatin g factor(GM-CSF) in the neutropenia by radiotherapy. MATERIALS AND METHODS: Eleven patients with various solid tumor were treated with a daily subcutaneous dose of GM-CSF(3-7 microgram/kg) for 5 days during the radiotherapy. Before and during the course of the study all the patients were monitored by the recording of physical examination, the complete blood count with differential and reticulocyte count and liver function test. Eight patients received patients received prior or concurrent chemotherapy. RESULTS: In 10 patients, the neutrophilic nadir was significantly elevated and the length of time that patients had a neutrophil count below 103/mm3, a threshold known to be critical to acquiring infective complications was shortened following GM-CSF injection. A significant rise (two fold or greater) of neutrophil count was seen in 10 of 11 patients. In most patients, discountinuation of GM-CSF resulted in a prompt return of granulocyte counts toward baseline. However the neutrophil count remained elevated over 103/mm3 during radiation therapy, and radiotherapy delays were avoided. Other peripheral blood components including monocytes and platelets also increased after GM-CSF treatment. No siginificant toxicity was encountered with subcutaneous GM-CSF treatment. CONCLUSION: GM-CSF was well tolerated by subcutaneous route and induced improvement in the neutropenia caused by radiotherapy.

Temperature distribution in VX-2 hepatoma heated with thermoseed hyperthermia / 대한치료방사선과학회지

It was the purpose of present study to develop a new thermoseed for heating deep-seated tumors and assessment of the effect of magnetic control on thermoseeds. Aqueous suspension of iron micro spheres (Ferropolysaccharide) was injected directly into the VX-2 hepatoma and heated with 1.2 MHz inductive radiofrequency unit. Aqueous thermoseed suspension was delivered to the tumor by simple percutaneous injection. The limitation of the thermoseed heating method is the positional change of thermoseed particles in the tumor after implantation. The thermoseed particles could enter the systemic blood circulation and cause a severe embolization of a critical organ. To minimize this limitation, we have used the magnetic control after loading the thermoseed in the tumor. When ferropolysaccharides were exposed to a strong magnetic field, they magnetized and subsequently exerted a magnetic force on each other, forming larger aggregates of particles. The size of aggregated particles were too big to enter the systemic blood circulation. Thus, unlike other thermoseed method, we hold the thermoseed particles stationary in the tumor. The temperature of the injected site and immediate vicinity elevated by 4-5degree C. The temperature of the surrounding normal hepatic tissue elevated by 1-2degree C only. The heating effect within the tumor was variable depending on the density of ferromagnetic aqueous suspension. Our results suggest that inductive heating of tumor injected with ferropolysaccharide solution offers the possibility of effective heat delivery to the defined tumor volume, which is difficult to heat with other heating devices.