• Radiation Oncology Journal
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• v.34 no.3
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• pp.193-201
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• 2016

Purpose: To assess the clinical outcomes of radiotherapy (RT) using two-dimensional (2D) and three-dimensional conformal RT (3D-CRT) for patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma to evaluate the effectiveness of involved field RT with moderate-dose and to evaluate the benefit of 3D-CRT comparing with 2D-RT. Materials and Methods: Between July 2003 and March 2015, 33 patients with stage IE and IIE gastric MALT lymphoma received RT were analyzed. Of 33 patients, 17 patients (51.5%) were Helicobacter pylori (HP) negative and 16 patients (48.5%) were HP positive but refractory to HP eradication (HPE). The 2D-RT (n = 14) and 3D-CRT (n = 19) were performed and total dose was 30.6 Gy/17 fractions. Of 11 patients who RT planning data were available, dose-volumetric parameters between 2D-RT and 3D-CRT plans was compared. Results: All patients reached complete remission (CR) eventually and median time to CR was 3 months (range, 1 to 15 months). No local relapse occurred and one patient died with second primary malignancy. Tumor response, survival, and toxicity were not significantly different between 2D-RT and 3D-CRT (p > 0.05, each). In analysis for dose-volumetric parameters, $D_{max}$ and CI for PTV were significantly lower in 3D-CRT plans than 2D-RT plans (p < 0.05, each) and $D_{mean}$ and V15 for right kidney and $D_{mean}$ for left kidney were significantly lower in 3D-CRT than 2D-RT (p < 0.05, each). Conclusion: Our data suggested that involved field RT with moderate-dose for gastric MALT lymphoma could be promising and 3D-CRT could be considered to improve the target coverage and reduce radiation dose to the both kidneys.

• Radiation Oncology Journal
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• v.31 no.3
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• pp.118-124
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• 2013

Purpose: The optimal treatment of advanced maxillary sinus cancer has been challenging for several decades. Intra-arterial chemotherapy (IAC) for head and neck cancer has been controversial. We have analyzed the long-term outcome of neoadjuvant IAC followed by radiation therapy (RT) and surgery. Materials and Methods: Twenty-seven patients with advanced maxillary sinus cancer were treated between 1989 and 2002. Five-fluorouracil (5-FU, $500mg/m^2$) was infused intra-arterially, and followed by RT (total 50.4 Gy/28 fractions). A planned surgery was performed 3 to 4 weeks after completion of IAC and RT. Results: At a median follow-up of 77 months (range, 12 to 169 months), the 5-year rates of overall survival in all patients were 63%. The 5-year rates of overall survival of stage T3/T4 patients were 70.0% and 58.8%, respectively. Seven of fourteen patients with disease recurrence had a local recurrence alone. The 5-year actuarial local control rates in patients with stage T3/T4, and in all patients were 20.0%, 32.3%, and 27.4%, respectively. Overall response rate after the completion of IAC and RT was 70.3%. During the follow-up, seven patients (25.9%) showed mild to moderate late complications. The tumor extent (i.e., the involvement of either orbit and/or base of skull) appeared to be related with local recurrence. Conclusion: Neoadjuvant IAC with 5-FU followed by RT and surgery may be effective to improve local tumor control in the patients with advanced maxillary sinus cancer. However, local failure was still the major cause of death. Further investigations are required to determine the optimal treatment schedule, radiotherapy techniques and chemotherapy regimens.

• Korean Journal of Head & Neck Oncology
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• v.27 no.1
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• pp.47-53
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• 2011

Purpose : Concurrent chemoradiotherapy(CCRT) with 3 weekly cisplatin is the standard treatment of locally advanced head and neck cancer(HNC). The aim is to evaluate the efficacy and toxicities of low-dose weekly cisplatin-based CCRT, which was devised to reduce the toxicity of CCRT. Method : We retrospectively analyzed HNC patients who received low-dose weekly cisplatin-based CCRT between 2008 and 2010. Cisplatin 35mg/$m^2$ was weekly given to all patients during radiotherapy. The efficacy was evaluated by the degree of clinical response, treatment failure and survival. The toxicity was evaluated by hematologic toxicities and oral mucositis. Results : A total of 27 patients were analyzed and median age was 59(range 31-81). The ratio of administered dose of radiotherapy and cisplatin to planned dose were 0.98 and 0.93, respectively. Complete remission and partial remission were 73% and 23%, respectively. Treatment failure was observed in 8(30%) patients. 1-year survival rate and 1-year disease free survival rate were 82% and 59%, respectively. Overall survival and progression-free survival did not reach median time. Grade 3/4 anemia, neutropenia, thrombocytopenia and oral mucositis were observed in 11%, 19%, 7% and 32% of patients, respectively. In terms of administered cycles, however, only 1-3% of grade 3/4 hematologic toxicities occurred among total 190 cycles. Severe oral mucositis were statistically associated with old age(p=0.003). Treatment failure had no statistical relation with age, pathology, primary site and stage. Conclusion : Low-dose weekly cisplatin-based CCRT seemed to deliver enough dose of cisplatin and to show low drop-out rate and good efficacy with low hematologic toxicities.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.131-136
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• 1987

Forty seven patients with locally recurrent uterine cerival cancer after surgery were treated with radiation during the 6 year period from 1979 through 1984 at the Department of Therapeutic Radiology of Seoul National University Hospital. In 30 out of the 47 patients, recurrence was diagnosed within 2 years after surgery. Site of recurrence was vagina in 19 patients, vagina and parametrium in 21 patients and parametrium only in 7 patients. Complete tumor control was achieved in 35 patients $(74.5\%)$; the complete response rates were $94.7\%(18/19)$ in vaginal recurrences, $57.1\%(12/21)$ in combined vaginal and parametrial recurrences and $71.4\%(5/7)$ in parametrial recurrences. Overall and disease free survival rates at 4 years were 55.2 and 50.1 percent, respectively, for entire group. Overall 4 year survival rates were $77.0\%$ for vaginal recurrences, $44.1\%$ for vaginal and parametrial recurrences and $42.9\%$ for parametrial recrrences. When the disease extent was classified in the same way as the staging system of FIGO, the 4 year survival was 80.4, 73.0, 25.0 and 0 percent for stage IIa, IIb, IIIb and IVa, respectively.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.363-367
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• 1993

A retrospective analysis was peformed on 42 patients with carcinoma of the uterine cervix who were treated with external beam (EB) radiation therapy alone at the Department of Therapeutic Radiology, Seoul National University Hospital from March 1979 to December 1988. After whole pelvic field irradiation of 50Gy, all the patients received additional booster dose of 12-22Gy to the primary tumor Thirty one received EB radiotherapy alone because of poor geometry for intracavitary application,5 because of medical problems and 6 because of other reasons. Five year locoregional control rate and five year survival rate were $34.5\%\;and\;35.4\%,$ respectively. Five year survivals were $66.7\%,\;36.4%,\;32.8\%\;and\;25.0\%$ for stage IIA, IIB, IIIB and IVA, respectively. The response one month after treatment well correlated with prognosis. The incidence of grade 2 and 3 complication was $12\%\;and\;10\%,$ respectively. There was tendency of increased complication with advanced stage.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.211-216
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• 2022

In radiation therapy, accurate Quality Assurance (QA) is required to irradiate tumor tissue while minimizing damage to normal tissue. Therefore, a dosimeter that can accurately measure radiation is needed. The purpose of this study is to develop a highly efficient radiation dosimeter with high sensitivity by applying a particle in binder method that can reduce manufacturing costs and simplify processes to perovskite materials that are cheaper and simpler to manufacture. By evaluating the response characteristics to high-energy photon, the applicability of QA dosimeter to radiation therapy was evaluated. As a result of reproducibility evaluation, RSD at 6 MV energy was presented as 1.178% and 15 MV energy was presented as 1.141%. As a result of linearity evaluation according to linear regression analysis, R² values of 0.9999 were presented under each condition of 6 MV and 15 MV energy. It was found that the CsPbBr₃ dosimeter manufactured based on the results of reproducibility and linearity evaluation is highly applicable as a QA dosimeter in the field of therapeutic radiation. The CsPbBr₃ dosimeter manufactured in this study presented more than the standard performance in the evaluation of reproducibility and linearity, and it can be used as a radiotherapy QA dosimeter through improvement.

• Radiation Oncology Journal
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• v.22 no.2
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• pp.98-105
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• 2004

Purpose : To evaluate whether positron omission tomography (PET) with 2-[F-18]fluoro-2-deoxy-D-giucose(FDG) can be used to predict of early response to definitive aim radlotherapy (RT) in squamous cell carcinoma of the head and neck using response rate and locoreglonal control as study endpoints. Materials and Methods : Twenty-two patients with head and neck cancer underwent a FDG-PET study before RT, after a flrst dose of 45 Gy, and after a second dose on more 4han 70 Gy. Standard uptake value (SUV) was calculated for primary tumor (n=22) and neck lymph node (n:10). Attenuation corrected PET scans acquired 60 min after tracer injection were used for evaluation of FDG uptake In tumors. A quantitative FDG uptake index was expressed as Suvlean (corrected for iean body mass). The follow-up time was at least 5 months (range S-1 S months). Results : A total of 22 primary tumors and 10 metastatic lymph nodes were analyzed In FDG-PET. In the first PET study the mean SUVlean the primary tumors and nodes were 5.4 (SD, 2.5) and 4.6 (SD, 2.3), respectively. In the second PET, study peformed after 46 Gy RT the mean SUV in primary tumor and node decreased to 2.9 (SD, 1.9, p<0.001) and 1.7 (SD, 1.3) respectively. in the third PET study peformed at the full dose (more than 70 Gy), RT the mean SUV In the primary tumors and nodes decreased to 2.3 (SD, 1.5, p<0.001) and 1.5 (SD, 1 .1) respectively. Conclusions: FDG uptake In tumors showed a significant decrease after the 45 Gy and more than 70 Gy of RT for squamous cell carcinoma of the head and neck. Reduction of metabolic activity after 46 Gy of radiotherapy Is closely correlated with radiation response.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4733-4738
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• 2014

Purpose: We developed and evaluated a regimen including fotemustine, teniposide and dexamethasone (FTD) for treating patients with central nervous system (CNS) lymphoma based on pharmacokinetic properties of individual agents and in combination. Patients and Methods: In a comparison study, 8 patients with primary CNS lymphoma (PCNSL) and 8 with secondary CNS lymphoma (SCNSL) were treated with FTD (comprising fotemustine 100 mg/m2, 1h infusion, day 1; teniposide 60 mg/m2, >0.5 h infusion, on day 2, 3, 4; dexamethasone 40 mg, 1h infusion, on day 1, 2, 3, 4 and 5; and methotrexate 12 mg, cytosine arabinoside 50 mg plus dexamethasone 5 mg intrathecally, on day 2 and 7). Cycles were repeated every 3 weeks. After response assessment, patients received whole brain radiotherapy. Results: Of the 8 PCNSL patients, 4 (50%) achieved CR and 3 (38%) PR, an overall response rate of 88%. Four patients (50%) were in continuing remission at the end of this study after a median follow-up of 30 months (range 10 to 56 months). Of the 8 SCNSL patients the overall response rate was 63% (CR+PR: 38%+25%). All responses were achievable with predictable toxicity mainly reflecting reversible myelosuppression. Conclusion: This study suggests that FTD could be an effective treatment for CNS lymphoma, and is worthy of further evaluation.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.256-260
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• 1999

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.

• Radiation Oncology Journal
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• v.3 no.1
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• pp.41-50
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• 1985

63 patients who were irradiated with a goal of long term control among 101 patients with esophageal cancer seen during an 11 fears period between Jan, 1970 and Dec, 1980 at Yonsei Cancer Center in Seoul, Korea have retrospectively analysed. 52(82.5%) among the 63 Patients were confirmed to have epidermoid carcinoma in the histology. 46 cases(73.0%) except 17 cases of $T_1$, were locally or far advanced extension. Tumor dose of radical radiation in the management of esophageal cancer had delivered from 50 Gy to 74 Gys. 2 Gys daily fractions, between 5weeks and 8 weeks. After 1 month from the completion of radiation, 23 of the 63 patients had a repeat barium esophagogram for the assessment of tumor response, there had showed 7 cases of complete response and 15 cases of partial response. 45(71.4%) patients were followed up and the remaining 18 patients were lost to follow-up within 1 year after the completion of irradiation. Actuarial overall 3 and 5 years survival rate of all 63 Patients were 11.8% and 8.8%, respectively. The actuarial 3 and 5 years survival rates of 17 cases of $T_1$, esophageal cancer were 24.7% and 20.8%. Statistically, there was no significant difference in survival rate according to tumor location (p>0.05). Radical Radiotherapy, Esophageal Cancer