• Radiation Oncology Journal
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• v.26 no.1
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• pp.24-34
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• 2008

Purpose: To assess the efficacy of the use of accelerated hyperfractionated radiotherapy(AHRT) for locally advanced uterine cervix cancers. Materials and Methods: Between May 2000 and September 2002, 179 patients were identified with FIGO stage IIB, IIIB, and IVA cancers. Of the 179 patients, 45 patients were treated with AHRT(AHRT group) and 134 patients were treated with conventional radiotherapy(CRT group), respectively. Patients undergoing the AHRT regimen received a dose of 30 Gy in 20 fractions(1.5 $Gy{\times}2$ fractions/day) to the whole pelvis. Subsequently, with a midline block, we administered a parametrial boost with a dose of 20 Gy using 2 Gy fractions. Patients also received two courses of low-dose-rate brachytherapy, up to a total dose of 85{\sim}90 Gy to point A. In the CRT group of patients, the total dose to point A was $85{\sim}90$ Gy. The overall treatment duration was a median of 37 and 66 days for patients that received AHRT and CRT, respectively. Statistical analysis was calculated by use of the Kaplan-Meier method, the log-rank test, and Chi-squared test. Results: For patients that received cisplatin-based concurrent chemotherapy and radiotherapy, the local control rate at 5 years was 100% and 79.2% for the AHRT and CRT group of patients, respectively(p=0.028). The 5-year survival rate for patients with a stage IIB bulky tumor was 82.6% and 62.1% for the AHRT group and CRT group, respectively(p=0.040). There was no statistically significant difference for severe late toxicity between the two groups(p=0.561). Conclusion: In this study, we observed that treatment with AHRT with concurrent chemotherapy allows a significant advantage of local control and survival for locally advanced uterine cervix cancers.

• Progress in Medical Physics
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• v.15 no.1
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• pp.9-16
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• 2004

The intensity modulated radiation therapy (IMRT) is believed to be on of the best treatment techniques for the goal of radiation therapy: to irradiate fatal dose to tumor region while minimizing dose to critical organs. It is essential to have comprehensive quality assurance program to assure the precision and the accuracy of the treatment due to the characteristic of the IMRT. The quality assurance technique for the Corvus treatment planning system was developed and its effectiveness was tested with the treatment planning of H&N region. Acrylic phantom, film and ionization chamber were used for this study, the discrepancy between the treatment planning and the film measurements showed 0.03 cm and 0.28 cm for the 90% of isodose line in each directions. Dose measurements showed 1% and 1.2% differences for ionization chamber and TLD, respectively. This concluded that the system can be used for clinic.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.173-176
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• 1987

Carcinoma of extrahepatic biliary tract is slow growing tumor but curative resection is rarely successful. Radiation therapy has been introduced for enhancing palliation and possible longterm survival. We treated a case of advanced extrahepatic biliary tract carcinoma with high dose rate remote afterloading system through T-tube as a initial irradiation postoperatively. We hope that this treatment may affect not only ennancing palliation and better quality of life but also in local tumor control.

• Progress in Medical Physics
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• v.24 no.4
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• pp.284-289
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• 2013

A study was performed comparing dosimetric characteristics of volumetric modulated arc and intensity modulated radiatio therapy on patients with bilateral breast cancer. For 5 patients, 3 plans were made for each patient; IMRT beams 8 and 12 of the beam intensity modulated radiation therapy, volumetric modulated arc therapy plan. The average PTVs volumes and $D_{98}$ for 12-IMRT were $51.04{\pm}0.57$ Gy (right), $50.80{\pm}1.07$ Gy (left), $42.94{\pm}16.16$ Gy (right), $42.56{\pm}2.09$ Gy (left). HI ($D_5{\sim}D_{95}$) and $CI_{90,95}$, even 12-IMRT has shown excellent results. In OAR, 3 plans showed excellent results. But the lowest dose of 12-IMRT. 12-IMRT achieved similar PTV coverage and sparing of organs at risk than 8-IMRT and VMAT.

• Progress in Medical Physics
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• v.3 no.1
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• pp.45-52
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• 1992

Authors started IORT for stomach cancer patient on 1988 and rectal cancer on 1991. We devloped various sized. shaped IORT cones for better clinical application and homogeneous surface and depth dose distribution. Authors obtained results as following. 1. The acryl cover fixed on the end for rectal IORT cone not only improvement of surface dose but also flattness of dose distribution. 2. Dose distribution of elliptical cone were shown almost 100% at inner field. 3. The output with acryl cone size were similar output of made electron cone.

• Journal of Yeungnam Medical Science
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• v.9 no.2
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• pp.312-320
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• 1992

Radiotherapeutically, nasopharyngeal cancer is an important disease in korea. Because of its blind anatomic location, early detection is relatively uncommon. Clinically, most of cases are locally advanced and nodal involvement are common. Recently better understanding of nature of the disease and improvement of radio-therapy technique permit better treatment results, including locoregional control and survival rate, and minimal normal tissue damages comparing with previously published data. We analyzed 31 patients of pathologically proven and previously untreated naso-pharyngeal carcinoma with different treatment techniques, retrospectively. Minimal and maximal follow up period of the survuor is 6 months and 68 months, respectively. Thirteen patients with squamous cell carcinoma are included in this analysis. The median age is 49 years(range from 20 to 64 years). Twenty two patients are stage III. Eleven patients are treated with radiotherapy alone and 20 are treated with comblined modalities treatment. The degree of responses after radiotherapy are categorized by 3-classes, i.e. complete response, partial response. In spite of simioarities of complete response rate and 1-year survival rate between two different treatment techniques, those patients with undifferentiated carcinoma appear to benefit from the adjuvant chemotherapy. In addition, systemic failure is more prominant in radiotherapy alone group than in combined modalities treatment group. These results suggest that adjuvant therapy in the radiotherapeutic management of nasopharyngeal cancers needs additional research according to histologic types and future extensive clinical trials.

• Radiation Oncology Journal
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• v.10 no.2
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• pp.193-204
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• 1992

During the period between March 1983 and December 1990, 74 patients with esophageal carcinoma (EG) were treated with radiation therapy (RT) at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, Catholic University Medical College. Of these, 6 patients were lost to follow-up, and 13 patients were interrupted. So the remaining 55 patients were analyzed, retrospectively. 32 patients were irradiated with curative aim, 12 patients with palliative intent, 10 patients postoperatively, and 1 patient pre- and post-operatively. Among these 55 patients, 28 patients were treated with chemoradiation modality, and 27 patients with RT alone. All patients were followed for a minimum of 20 months or until death. Of 32 patients irradiated by curative aim, 22 patients (69%) showed partial remission (PR), 6 patients (19%) complete remission (CR). Overall mean survival and two-year survival rate were 15.6 months and 22%. With respect to sex, age, pathologic differentiation, tumor location, tumor size, stage, RT aim, RT response, RT dose, use of chemotherapy and functional categories (FC) of dysphagia at initiation of RT and at finishing RT: Tumor size, stage, RT response had great influences on prognosis and FC at finishing RT had a slight influence on prognosis. Especially, the mean survival and 2-year survival rate in patients with postoperative RT were 24.7 months and 63%, which could be compared with 29.1 months and 43% in radically treated patients with CR. And the mean survival duration and 2-year survival rate in patients irradiated with doses more than 60 Gy were 22.4 months and 29%, and 50~60 Gy were 12.2 months and 12%, respectively. However, no significant difference was shown statistically. Among 12 patients treated with palliative intent, 9 patients (75%) had good improvement in dysphagia and the mean duration of palliative response was 10.6 months.

• Radiation Oncology Journal
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• v.25 no.2
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• pp.101-108
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• 2007

[ $\underline{Purpose}$ ]: To compare radiation therapy alone to combined modality therapy about survival rate and tolerance of elderly patients ($70=or{\geq}$) with non-small-cell lung cancer (NSCLC). $\underline{Materials\;and\;Methods}$: Between 1998 and 2002, 57 patients given radiation therapy due to NSCLC (Stage III) were analysed retrospectively. Radiation therapy alone (RT), concurrent chemoradiation (CRT), and sequential chemoradiation (SCRT) was done to 33, 16 and 8 patients, respectively. Patients' median age was 74 (range $70{\sim}85$). Male and female are 51 patients and 6 patients, respectively. 23 patients were stage IIIa and 34 were stage IIIb. Patients' characteristic distribution of RT and CRT was not significantly different except mass size that RT has a bigger than CRT. The fraction size of radiation therapy was 1.8 Gy in CRT and $1.8{\sim}3\;Gy$ in other groups. Total radiation dose was $51{\sim}63\;Gy$ according to the fraction size. If the prescribed total radiation dose was successfully irradiated, we stated that it was completion of radiation therapy. $\underline{Results}$: 52 patients were dead. Median period of radiation therapy was as follow: RT, 35 days, CRT, 60.5 days and SCRT, 35 days. Overall median survival time (MST) was 10.1 months. The 1 yr- and 2 yr-overall survival rate was 39.8% and 17.6%, respectively. MST of RT, CRT and SCRT was 8.9, 8.2 and 11.7 months, respectively. The 1 yr survival rate of RT, CRT and SCRT was 38.4%, 37.5% and 50% (not significant). Patients given incomplete radiation therapy were 12 (RT, 5 CRT, 6 SCRT, 1). N stage (p=0.081) and the difference of treatment methods (p=0.079) were the factors affecting incompletion of radiation therapy, but it was not significant. In case of combined-agents chemotherapy, 4 of 8 ceased radiation therapy. T stage ($T{\geq}3$), mass size (${\geq}5\;cm$), Karnofsky performance scale (${\leq}70$) and completion of radiation therapy were the prognostic factors in uni- and multi-variate analysis. $\underline{Conclusion}$: In elderly patients with NSCLC, radiation therapy alone was a treatment method with similar survival period compared with other methods. Generally, patients given radiation therapy alone was tolerable to a treatment. Before planning concurrent chemoirradiation in elderly patients with NSCLC, physicians pay attention to a selection of patients and chemotherapy agents considering general condition and toxicity.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.294-299
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• 2006

$\underline{Purpose}$: Using cone beam CT, we can compare the position of the patients at the simulation and the treatment. In on-line image guided radiation therapy, one can utilize this compared data and correct the patient position before treatments. Using cone beam CT, we investigated the errors induced by setting up the patients when use only the markings on the patients' skin. $\underline{Materials\;and\;Methods}$: We obtained the data of three patients that received radiation therapy at the Department of Radiation Oncology in Chung-Ang University during August 2006 and October 2006. Just as normal radiation therapy, patients were aligned on the treatment couch after the simulation and treatment planning. Patients were aligned with lasers according to the marking on the skin that were marked at the simulation time and then cone beam CTs were obtained. Cone beam CTs were fused and compared with simulation CTs and the displacement vectors were calculated. Treatment couches were adjusted according to the displacement vector before treatments. After the treatment, positions were verified with kV X-ray (OBI system). $\underline{Results}$: In the case of head and neck patients, the average sizes of the setup error vectors, given by the cone beam CT, were 0.19 cm for the patient A and 0.18 cm for the patient B. The standard deviations were 0.15 cm and 0.21 cm, each. On the other hand, in the case of the pelvis patient, the average and the standard deviation were 0.37 cm and 0.1 cm. $\underline{Conclusion}$: Through the on-line IGRT using cone beam CT, we could correct the setup errors that could occur in the conventional radiotherapy. The importance of the on-line IGRT should be emphasized in the case of 3D conformal therapy and intensity-modulated radiotherapy, which have complex target shapes and steep dose gradients.

• 대한두경부종양학회:학술대회논문집
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• 1994.11a
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• pp.17.1-17.1
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• 1994