A Survey of Radiation Therapy Utilization in Korea from 2010 to 2016: Focusing on Use of Intensity-Modulated Radiation Therapy

BACKGROUND: This study aimed to assess the recent changes of radiation therapy (RT) modalities in Korea. In particular, we focused on intensity-modulated radiation therapy (IMRT) utilization as the main index, presenting the application status of advanced RT. METHODS: We collected information from the Korean Health and Insurance Review and Assessment Service data based on the National Health Insurance Service claims and reimbursements records by using treatment codes from 2010 to 2016. We classified locating region of each institution as capital vs. non-capital areas and metropolitan vs. non-metropolitan areas to assess the regional difference in IMRT utilization in Korea. RESULTS: IMRT use has been steadily increased in Korea, with an annual increase estimate (AIE) of 37.9% from 2011 to 2016 (P < 0.001) resulting in IMRT being the second most common RT modality following three-dimensional conformal radiotherapy. In general, an increasing trend of IMRT utilization was observed, regardless of the region. The rate of AIE in the capital areas or metropolitan areas was higher than that in non-capital areas or non-metropolitan areas (40.7% vs. 31.9%; P < 0.001 and 39.7% vs. 29.4%; P < 0.001, respectively). DISCUSSION: The result of our survey showed that IMRT has become one of the most common RT modalities. IMRT is becoming popular in both metropolitan and non-metropolitan areas, while metropolitan area has faster AIE possibly due to concentration of medical resources and movement of advanced patients.

Analysis of the Reasons for Donor Deferral after Introduction of the Electronic Donor Health Questionnaire Program / 대한수혈학회지

BACKGROUND: Electronic Donor Health Questionnaire (e-DHQ) could prevent omissions in filling in the questionnaire. Compared with the paper Donor Health Questionnaire (p-DHQ), it can expect honest answers from donors to the questions relating to high risk behaviors. The aim of this study is to evaluate the effect of e-DHQ on the answers from donors by analyzing variations of the reasons for deferral after the introduction of e-DHQ to the Korean Red Cross (KRC). METHODS: The reasons for deferral determined by p-DHQ in 2008~2011 and by e-DHQ in 2011~2014, which have been accumulated in the database of the Blood Information Management System in KRC, were analyzed and compared. RESULTS: The results showed that the deferral rates for the general health status and medication taken were 0.47% (P=0.0100) and 0.16% (P=0.0103) higher in e-DHQ than in p-DHQ. In particular, for questions including hunger, lack of sleep, fatigue, endoscopy, dental treatment, surgery, tattoo, and acupuncture, the proportion of answers was higher in e-DHQ than in p-DHQ. CONCLUSION: The deferral rates for general health status and medication taken increased after the implementation of e-DHQ. The rate of deferral by some details of general health status, medical treatment for recent one month, and history for recent one year also increased because e-DHQ induced donors to give straightforward answers. e-DHQ is expected to contribute to the strengthening of health protection of blood donors and recipients. However the questions relating to high risk behaviors should be reformed so that honest answers can be induced from donors.

Evaluation of Point-of-Care Testing Devices for Pre-donation Alanine Aminotransferase Test / 대한수혈학회지

BACKGROUND: In Korea, since 1990, in an effort to reduce the transmission of non-A, non-B hepatitis, all blood donations with alanine aminotransferase (ALT) levels above 65 IU/L are discarded. In 2012, 64.8% of the disposed blood units at the Korean Red Cross blood centers were due to high ALT levels. Pre-donation ALT testing might prevent unnecessary blood donation and save related expenses. We evaluated performance of point-of-care test (POCT) devices for pre-donation ALT screening. METHODS: ALT levels by four ALT POCT devices (Mission C100, Acon; Reflotron Plus, Roche; Labgeo PT10, Samsung; and FDC NX500, Fujifilm) were compared with venous blood results using laboratory chemistry analyzers (AU series, Beckman Coulter Inc.). Intraclass correlation coefficients (ICCs), sensitivity (ability to detect ALT > or =65 IU/L), and specificity (ability to detect <65 IU/L) for each method were calculated. RESULTS: Compared with the laboratory analyzers, the ICCs of ALT measurements by Mission C-100, Reflotron Plus, Labgeo PT10, and FDC NX500 were 0.96 (95% confidence interval (CI): 0.95~0.97), 0.99 (95% CI: 0.99~0.99), 0.98 (95% CI: 0.98~0.98), and 0.94 (95% CI: 0.91~0.96), respectively. The sensitivity was 80.95% for Mission C-100, 83.33% for Reflotron Plus, 78.57% for Labgeo PT10, and 97.62% for FDC NX500. The specificity was 99.13% for Mission C-100, 100.00% for Reflotron Plus, 99.78% for Labgeo PT10, and 98.26% for FDC NX500. CONCLUSION: The ALT POCT devices showed almost perfect agreement with the laboratory analyzers and could be useful for pre-donation ALT screening. However, before implementing ALT POCT devices, cost-effectiveness analyses should be performed.

Multicenter Validation Study of a Prognostic Index for Portal Vein Tumor Thrombosis in Hepatocellular Carcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We previously reported on a staging system and prognostic index (PITH) for portal vein tumor thrombosis (PVTT) in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT) at a single institution. The aim of this study is to validate the PITH staging system using data from patients at other institutions and to compare it with other published staging systems. MATERIALS AND METHODS: A total of 994 HCC patients with PVTT who were treated with RT between 1998 and 2011 by the Korean Radiation Oncology Group were analyzed retrospectively. All patients were staged using the Cancer of the Liver Italian Program (CLIP), Japanese Integrated Staging (JIS), Okuda, and PITH staging systems, and survival data were analyzed. The likelihood ratio, Akaike information criteria (AIC), time-dependent receiver operating characteristics, and prediction error curve analysis were used to determine discriminatory ability for comparison of staging systems. RESULTS: The median survival was 9.2 months. Compared with the other staging systems, the PITH score gave the highest values for likelihood ratio and lowest AIC values, demonstrating that PITH may be a better prognostic model. Although the values were not significant and differences were not exceptional, the PITH score showed slightly better performance with respect to time-dependent area under curve and integrated Brier score of prediction error curve. CONCLUSION: The PITH staging system was validated in this multicenter retrospective study and showed better stratification ability in HCC patients with PVTT than other systems.

Sequential chemotherapy followed by radiotherapy versus concurrent chemoradiotherapy in patients with stage I/II extranodal natural killer/T-cell lymphoma, nasal type

BACKGROUND: The purpose of this report is to summarize our clinical experience of patients with stage I/II extranodal natural killer (NK)/T-cell lymphoma, nasal type, treated using sequential chemotherapy followed by radiotherapy (SCRT) or concurrent chemoradiotherapy (CCRT). METHODS: Forty-three patients with stage I/II extranodal NK/T-cell lymphoma, nasal type, who received SCRT (16 patients) or CCRT (27 patients) were included in the present analysis. RESULTS: The median follow-up time was 39 months (range, 4-171 months) for all patients, 77 months (range, 4-171 months) for the SCRT group, and 31 months (range, 6-132 months) for the CCRT group. There were no statistically significant differences between the SCRT and CCRT groups with regard to the 3-year progression-free survival (PFS) (56% vs. 41%, P=0.823) and 3-year overall survival (OS) (75% vs. 59%, P=0.670). Univariate analysis revealed that patients with tumors confined to the nasal cavity and patients achieved complete remission had better PFS and OS rates, regardless of the treatment sequence. Multivariate analysis revealed that patients with tumors confined to the nasal cavity and patients aged < or =60 years had better OS rates. CONCLUSION: The effect of SCRT and CCRT are similar in terms of survival outcomes of patients with stage I/II extranodal NK/T-cell lymphoma, nasal type. Our results show that tumors confined to the nasal cavity and an age < or =60 years were associated with a better prognosis.

Treatment outcome of conservative surgery plus postoperative radiotherapy for extremity soft tissue sarcoma

PURPOSE: To evaluate the treatment outcome and prognostic factor of postoperative radiotherapy for extremity soft tissue sarcoma (STS). MATERIALS AND METHODS: Forty three patients with extremity STS were treated with conservative surgery and postoperative radiotherapy from January 1981 to December 2010 at Korea University Medical Center. Median total 60 Gy (range, 50 to 74.4 Gy) of radiation was delivered and 7 patients were treated with chemotherapy. RESULTS: The median follow-up period was 70 months (range, 5 to 302 months). Twelve patients (27.9%) sustained relapse of their disease. Local recurrence occurred in 3 patients (7.0%) and distant metastases developed in 10 patients (23.3%). The 5-year overall survival (OS) was 69.2% and disease free survival was 67.9%. The 5-year local relapse-free survival was 90.7% and distant relapse-free survival was 73.3%. On univariate analysis, no significant prognostic factors were associated with development of local recurrence. Histologic grade (p = 0.005) and stage (p = 0.02) influenced the development of distant metastases. Histologic grade was unique significant prognostic factor for the OS on univariate and multivariate analysis. Severe acute treatment-related complications, Common Terminology Criteria for Adverse Events (CTCAE) grade 3 or 4, developed in 6 patients (14.0%) and severe late complications in 2 patients (4.7%). CONCLUSION: Conservative surgery with postoperative radiotherapy achieved a satisfactory rate of local control with acceptable complication rate in extremity STS. Most failures were distant metastases that correlate with tumor grade and stage. The majority of local recurrences developed within the field. Selective dose escalation of radiotherapy or development of effective systemic treatment might be considered.

Radiotherapy for pituitary adenomas: long-term outcome and complications

PURPOSE: To evaluate long-term local control rate and toxicity in patients treated with external beam radiotherapy (EBRT) for pituitary adenomas. MATERIALS AND METHODS: We retrospectively reviewed the medical records of 60 patients treated with EBRT for pituitary adenoma at Korea University Medical Center from 1996 and 2006. Thirty-five patients had hormone secreting tumors, 25 patients had non-secreting tumors. Fifty-seven patients had received postoperative radiotherapy (RT), and 3 had received RT alone. Median total dose was 54 Gy (range, 36 to 61.2 Gy). The definition of tumor progression were as follows: evidence of tumor progression on computed tomography or magnetic resonance imaging, worsening of clinical sign requiring additional operation or others, rising serum hormone level against a previously stable or falling value, and failure of controlling serum hormone level so that the hormone level had been far from optimal range until last follow-up. Age, sex, hormone secretion, tumor extension, tumor size, and radiation dose were analyzed for prognostic significance in tumor control. RESULTS: Median follow-up was 5.7 years (range, 2 to 14.4 years). The 10-year actuarial local control rates for non-secreting and secreting adenomas were 96% and 66%, respectively. In univariate analysis, hormone secretion was significant prognostic factor (p = 0.042) and cavernous sinus extension was marginally significant factor (p = 0.054) for adverse local control. All other factors were not significant. In multivariate analysis, hormone secretion and gender were significant. Fifty-three patients had mass-effect symptoms (headache, dizziness, visual disturbance, hypopituitarism, loss of consciousness, and cranial nerve palsy). A total of 17 of 23 patients with headache and 27 of 34 patients with visual impairment were improved. Twenty-seven patients experienced symptoms of endocrine hypersecretion (galactorrhea, amenorrhea, irregular menstruation, decreased libido, gynecomastia, acromegaly, and Cushing's disease). Amenorrhea was abated in 7 of 10 patients, galactorrhea in 8 of 8 patients, acromegaly in 7 of 11 patients, Cushing's disease in 4 of 4 patients. Long-term complication was observed in 4 patients; 3 patients with cerebrovascular accident, 1 patient developed dementia. Of these patients, 3 of 4 received more than 60 Gy of irradiation. CONCLUSION: EBRT is highly effective in preventing recurrence and reducing mass effect of non-secreting adenoma. Effort to improve tumor control of secreting adenoma is required. Careful long-term follow-up is required when relatively high dose is applied. Modern radiosurgery or proton RT may be options to decrease late complications.

Long-Term Results of 2-Dimensional Radiation Therapy in Patients with Nasopharyngeal Cancer / 대한방사선종양학회지

PURPOSE: To analyze the treatment outcomes, complications, prognostic factors after a long-term follow-up of patients with nasopharyngeal carcinoma treated with radiation therapy (RT) alone or concurrent chemoradiation therapy (CCRT). MATERIALS AND METHODS: Between December 1981 and December 2006, 190 eligible patients with non-metastatic nasopharyngeal carcinoma were treated at our department with a curative intent. Of these patients, 103 were treated with RT alone and 87 patients received CCRT. The median age was 49 years (range, 8~78 years). The distributions of clinical stage according to the AJCC 6th edition included I: 7 (3.6%), IIA: 8 (4.2%), IIB: 33 (17.4%), III: 82 (43.2%), IVA: 31 (16.3%), IVB: 29 (15.3%). The accumulated radiation doses to the primary tumor ranged from 66.6~87.0 Gy (median, 72 Gy). Treatment outcomes and prognostic factors were retrospectively analyzed. Acute and late toxicities were assessed using the RTOG criteria. RESULTS: A total of 96.8% (184/190) of patients completed the planned treatment. With a mean follow-up of 73 months (range, 2~278 months; median, 52 months), 93 (48.9%) patients had relapses that were local 44 (23.2%), nodal 13 (6.8%), or distant 49 (25.8%). The 5- and 10-year overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) rates were 55.6% and 44.5%, 54.8% and 51.3%, in addition to 65.3% and 57.4%, respectively. Multivariate analyses revealed that CCRT, age, gender, and stage were significant prognostic factors for OS. The CCRT and gender were independent prognostic factors for both DFS and DSS. There was no grade 4 or 5 acute toxicity, but grade 3 mucositis and hematologic toxicity were present in 42 patients (22.1%) and 18 patients (9.5%), respectively. During follow-up, grade 3 hearing loss in 9 patients and trismus in 6 patients were reported. CONCLUSION: The results of our study were in accordance with findings of previous studies and we confirmed that CCRT, low stage, female gender, and young age were related to improvement in OS. However, there are limitations in the locoregional control that can be achieved by CCRT with 2D conventional radiation therapy. This observation has led to further studies on clarifying the efficacy of concurrent chemotherapy by intensity modulated radiation therapy.

Treatment Outcome and Analysis of the Prognostic Factors of High Grade Glioma Treated by Postoperative Radiotherapy / 대한방사선종양학회지

PURPOSE: To analyze the postoperative radiotherapy results and prognostic factors in patients with WHO grade 3 and 4 gliomas. MATERIALS AND METHODS: A total of 99 patients with malignant gliomas who underwent postoperative radiotherapy between 1988 and 2007 were enrolled in this study. Total resections, subtotal resections (> or =50%), partial resections (<50%), and biopsies were performed in 16, 38, 22, and 23 patients, respectively. In total there were 32, 63 and 4 WHO grade 3, 4, and unspecified high grade gliomas, respectively. The biologically equivalent dose was in the range of 18.6 to 83.3 Gy(10) (median dose, 72.2 Gy(10)). We retrospectively analyzed survival rate, patterns of failure, prognostic factors, and adverse effects. RESULTS: The median follow-up time was 11 months and there were 54 patients (54.5%) with local failure. The one and 2-year survival rates were 56.6% and 29.3%, respectively, and the median survival duration was 13 months. The one and 2-year progression-free survival rates (PFS) were 31.3% and 18.2%, respectively, and the median PFS was 7 months. The prognostic factors for overall survival were age (p=0.0001), surgical extents (subtotal resection, p=0.023; partial resection, p=0.009; biopsy only, p=0.002), and enhancement of tumor in postoperative imaging study (p=0.049). The factors affecting PFS were age (p=0.036), tumor enhancement of the postoperative imaging study (p=0.006). There were 3 patients with grade 3 and 4 side effects during and after radiotherapy. CONCLUSION: In addition to age and surgical extents, tumor enhancement of the postoperative imaging study was included in the prognostic factors. The most common relapse patterns were local failures and hence, additional studies are needed to improve local control rates.

Intraoperative Radiation Therapy for Unresectable Pancreatic Cancer

PURPOSE: We wanted to evaluate the clinical effectiveness of intraoperative radiation therapy (IORT) in combination with external beam radiation therapy (EBRT) for treating unresectable or metastatic pancreatic cancer. METHODS: From August 1993 to July 2007, 28 patients with unresectable or metastatic pancreatic cancer received IORT (median: 20 Gy) combined with or without EBRT (median: 50.4 Gy). Eighteen patients were treated with IORT followed by EBRT, and 10 patients were treated by IORT alone. Eighteen patients underwent explolaparotomy and 10 patients underwent bypass surgery. RESULTS: The 1-year overall survival rate (OS) and the median survival time of all 28 patients were 21.4% and 7.5 months, respectively. The 1-year OS and median survival time for the clinical stage III patients were 33.3% and 10.2 months, respectively, and they were 7.7% and 5.1 months for the clinical stage IV patients, respectively (p=0.007). Univariate analyses revealed that the stage, chemotherapy and tumor volume were the significant prognostic factors for OS. The patients treated with IORT combined with EBRT had a more favorable 1-year local control rate than that of those patients treated with IORT alone (88.9% vs. 50.0, respectively, p=0.009). But the significant improvement in local control did not translate into a survival benefit. The addition of EBRT was an independent prognostic factor for improving the local control rate. The operative mortality was 0%. CONCLUSION: IORT combined with EBRT is considered to be effective in achieving local control and palliation for patients with unresectable or metastatic pancreatic cancer. Further, IORT seems to be safe and it does not increase the mortality or the incidence of surgical wound infection.

Recurrence Risk Factors after Radiotherapy in Early Glottic Cancer and Outcome of Salvage Treatment / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The aim of this study was to find risk factors for recurrence after curative radiotherapy in early glottic cancer and to analyze the result of treatment between salvage total laryngectomy and salvage conservation laryngectomy for recurrent glottic cancer. SUBJECTS AND METHOD: A retrospective analysis was performed for patients of 45 cases of early glottic cancer who were treated with curative radiotherapy from 1997 to 2004. The risk factors analyzed for recurrence in early glottic cancer were gender, age, anterior involvement, bilaterality, T stage and radiotherapy interruption. Fourteen patients who underwent salvage laryngectomy for recurrent glottic cancer were analyzed by Kaplan-Myer method to assess the results of salvage total laryngectomy and salvage conservation laryngectomy. RESULTS: Forty-two patients were male and only 3 patients were female, with the median age of 62.4 years. Radiotherapy interruption was found to be a risk factor significantly influencing recurrence in univariate and multivariate analyses. The 5-year overall survival rate in salvage total laryngectomy was 77% and that in salvage conservation laryngectomy was 75%. CONCLUSION: When a curative radiotherapy was interrupted in early glottic cancer before total dosage irradiation, the possibility of recurrence must be considered. In such cases, by choosing an adequate patient group combined with a proper surgical technique, optimal treatment results can be obtained by salvage conser-vation laryngectomy.

Development of a Web-based Donor Eligibility Expert System / 대한수혈학회지

BACKGROUND: The determination of blood donor eligibility has become critical and challenging to blood operators as so many conditions and restrictions should be considered to correctly decide the donor eligibility. Since the launching of the BIMS (Blood Information Management System) in May 2003, the demand of developing a more intelligent system to assist the determination of donor eligibility has been growing. The Korean Red Cross Blood Service intended to develop an expert system for donor eligibility determination with high efficiency and ease of use. METHODS: The content of the system was determined through the activity of a team consisting of medical doctors, nurses, safety managers, and the system developers. Algorithms were developed according to the donor history taking process. The efficiency of the system was tested by the comparison of the time needed for inquiries and the number of inappropriate blood collections before and after the implementation of the new system. RESULTS: The new system's user interface integrated many complicated work processes with a user-friendly flexibility. The types of decision included the restricted donations. The donor interviewers were highly satisfied with the system because almost all cases were correctly determined in a relatively short time. Using this system, the number of inappropriate blood collections was significantly lowered. CONCLUSION: We developed an expert system that can aide the donor eligibility determination process and prevent the violation of the related regulations. This system will contribute to enhancement of the blood safety as well as donor protection for our blood services.

Development of a Web-based Donor Eligibility Expert System / 대한수혈학회지

BACKGROUND: The determination of blood donor eligibility has become critical and challenging to blood operators as so many conditions and restrictions should be considered to correctly decide the donor eligibility. Since the launching of the BIMS (Blood Information Management System) in May 2003, the demand of developing a more intelligent system to assist the determination of donor eligibility has been growing. The Korean Red Cross Blood Service intended to develop an expert system for donor eligibility determination with high efficiency and ease of use. METHODS: The content of the system was determined through the activity of a team consisting of medical doctors, nurses, safety managers, and the system developers. Algorithms were developed according to the donor history taking process. The efficiency of the system was tested by the comparison of the time needed for inquiries and the number of inappropriate blood collections before and after the implementation of the new system. RESULTS: The new system's user interface integrated many complicated work processes with a user-friendly flexibility. The types of decision included the restricted donations. The donor interviewers were highly satisfied with the system because almost all cases were correctly determined in a relatively short time. Using this system, the number of inappropriate blood collections was significantly lowered. CONCLUSION: We developed an expert system that can aide the donor eligibility determination process and prevent the violation of the related regulations. This system will contribute to enhancement of the blood safety as well as donor protection for our blood services.

Clinical Factors Related to Suspected Second Primary Lung Cancer Development in Patients with Head and Neck Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The rate of second primary lung cancer development for patients with head and neck cancer (HNC) has been noted. The aim of our study was to evaluate the incidence and clinical features of suspected second primary lung cancer that developed in patients with primary HNC. MATERIALS AND METHODS: We conducted a retrospective study of 469 patients who were newly diagnosed with HNC at the Korea University Medical Center between January 2000 and December 2006. RESULTS: A total of 469 patients were included (389 men and 80 women). Eighteen patients (3.8%) had suspected second primary lung cancers. Statistically significant clinical variables for lung cancer development included the origin site for the primary HNC (oro-hypopharynx and larynx) (p=0.048), abnormal chest x-ray findings (p=0.027) and the histological HNC type (squamous cell carcinoma) (p=0.032). When the second primary lung cancers were combined with HNCs, the adjusted overall survival of patients with a second primary lung cancer was 16 months (p<0.001). CONCLUSIONS: Considering the relative risk factors for a second primary lung cancer developing in patients with HNC, advanced diagnostic tools, such as chest CT or PET CT scan, should be applied for the early detection of a second primary lung cancer.

The Palliative Effect of Endobronchial Brachytherapy for Previously Irradiated Patients with Lung Cancer / 대한방사선종양학회지

PURPOSE: To evaluate the palliative effect of endobronchial brachytherapy (EBB) for patients with lung cancer that previously received external beam radiotherapy (EBRT). MATERIALS AND METHODS: From July 1992 to May 2003, 29 patients with a recurrent or persistent lung cancer were treated with palliative EBB at our institute. EBB consisted of three fractions (once a week) of a dose of 5 Gy using the high dose-rate remote afterloader. Symptomatic improvement was assessed subjectively, and patients were divided into two groups according to whether symptoms were improved or not. Factors such as age, performance status, duration from EBRT to EBB and the location of the tumor were compared between the improved and unimproved groups of patients. RESULTS: Overall symptomatic improvement was found in 27 out of 52 symptoms (52%). Improvement as to the type of symptoms was seen in 41%, 50%, 82% and 33% of patients with cough, dyspnea, hemoptysis, and obstructive pneumonia respectively. The rate of improvement of hemoptysis was more than that of cough (p<0.05). The median time to symptom relapse was 5 months. The improved patient group (n=17, 59%) had a better performance status and longer duration from EBRT to EBB than the unimproved patient group (p<0.05). Lesions located in the distal trachea and/or main bronchus were found more frequently in the improved group of patients than in the unimproved group of patients, but the difference was not statistically significant (p =0.06). Fatal complications developed in two patients (7%), which were a hemoptysis and bronchopleural fistula respectively. CONCLUSION: Symptom improvement was found in 60% of patients after EBB and improvement was maintained for 5 months. Palliative EBB, even when EBRT was given previously, can be effective for a patient that has an endobronchial symptom, such as hemoptysis, and for a patient with good performance and a long duration from previous EBRT to EBB.

Real-time Body Surface Motion Tracking using the Couch Based Computer-controlled Motion Phantom (CBMP) and Ultrasonic Sensor: A Feasibility Study / 의학물리

Respiration gating radiotherapy technique developed in consideration of the movement of body surface and internal organs during respiration, is categorized into the method of analyzing the respiratory volume for data processing and that of keeping track of fiducial landmark or dermatologic markers based on radiography. However, since these methods require high-priced equipments for treatment and are used for the specific radiotherapy. Therefore, we should develop new essential method whilst ruling out the possible problems. This study aims to obtain body surface motion by using the couch based computer-controlled motion phantom (CBMP) and US sensor, and to develop respiration gating techniques that can adjust patients' beds by using opposite values of the data obtained. The CBMP made to measure body surface motion is composed of a BS II microprocessor, sensor, host computer and stepping motor etc. And the program to control and operate it was developed. After the CBMP was adjusted by entering random movement data, and the phantom movements were acquired using the sensors, the two data were compared and analyzed. And then, after the movements by respiration were acquired by using a rabbit, the real-time respiration gating techniques were drawn by operating the phantom with the opposite values of the data. The result of analyzing the acquisition-correction delay time for the data value shows that the data value coincided within 1% and that the acquisition-correction delay time was obtained real-time (2.34 x 10(-4) sec). And the movement was the maximum movement was 6 mm in Z direction, in which the respiratory cycle was 2.9 seconds. This study successfully confirms the clinical application possibility of respiration gating techniques by using a CBMP and sensor.

The Evaluation of Radiation Therapy and Combined-modality Therapy for Non-small-cell Lung Cancer in Elderly / 대한방사선종양학회지

PURPOSE: To compare radiation therapy alone to combined modality therapy about survival rate and tolerance of elderly patients (70=or> or =) with non-small-cell lung cancer (NSCLC). 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 70~85). 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 1.8~3 Gy in other groups. Total radiation dose was 51~63 Gy according to the fraction size. If the prescribed total radiation dose was successfully irradiated, we stated that it was completion of radiation therapy. 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> or =3), mass size (> or =5 cm), Karnofsky performance scale (< or =70) and completion of radiation therapy were the prognostic factors in uni- and multi-variate analysis. 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.

Effectiveness of Fentanyl Transdermal Patch (Fentanyl-TTS, Durogegic(R)) for Radiotherapy Induced Pain and Cancer Pain: Multi-center Trial / 대한방사선종양학회지

PURPOSE: To evaluate the effectiveness and safety of fentanyl-TTS in the management of radiotherapy induced acute pain and cancer pain treated with radiotherapy. MATERIALS AND METHODS: Our study was open labelled prospective phase IV multi-center study. the study population included patients with more 4 numeric rating scale(NRS) score pain although managed with other analgesics or more than 6 NRS score pain without analgesics. Patients divided into two groups; patients with radiotherapy induced pain (Group A) and patients with cancer pain treated with radiotherapy (Group B). All patients received 25 ug/hr of fentanyl transdermal patch. Primary end point was pain relief; second end points were change in patient quality of life, a degree of satisfaction for patients and clinician, side effects. RESULTS: Between March 2005 and June 2005, 312 patients from 26 participating institutes were registered, but 249 patients completed this study. Total number of patients in each group was 185 in Group A, 64 in Group B. Mean age was 60 years and male to female ratio was 76:24. Severe pain NRS score at 2 weeks after the application of fentanyl was decreased from 7.03 to 4.01, p=0.003. There was a significant improvement in insomnia, social functioning, and quality of life. A degree of satisfaction for patients and clinician was very high. The most common reasons of patients' satisfactions was good pain control. Ninety six patients reported side effect. Nausea was the most common side effect. There was no serious side effect. CONCLUSION: Fentanyl-TTS was effective in both relieving pain with good tolerability and improving the quality of life for patients with radiotherapy induced acute pain and cancer pain treated with radiotherapy. The satisfaction of the patients and doctors was good. There was no major side effect.

Dosimetric Verification of Dynamic Conformal Arc Radiotherapy / 의학물리

The purpose of this study is to develop the optimization method for adjusting the film isocenter shift and to suggest the quantitative acceptable criteria for film dosimetry after optimization in the dynamic conformal arc radiation therapy (DCAR). The DCAR planning was performed in 7 patients with brain metastasis. Both absolute dosimetry with ion chamber and relative film dosimetry were performed throughout the DCAR using BrainLab's micro-multileaf collimator. An optimization method for obtaining the global minimum was used to adjust for the error in the film isocenter shift, which is the largest part of systemic errors. The mean of point dose difference between measured value using ion chamber and calculated value acquired from planning system was 0.51+/-0.43% and maximum was 1.14% with absolute dosimetry. These results were within the AAPM criteria of below 5%. The translation values of film isocenter shift with optimization were within +/-1 mm in all patients. The mean of average dose difference before and after optimization was 1.70+/-0.36% and 1.34+/-0.20%, respectively, and the mean ratios over 5% dose difference was 4.54+/-3.94% and 0.11+/-0.12%, respectively. After optimization, the dose differences decreased dramatically and a ratio over 5% dose difference and average dose difference was less than 2%. This optimization method is effective in adjusting the error of the film isocenter shift, which is the largest part of systemic errors, and the results of this research suggested the quantitative acceptable criteria could be accurate and useful in clinical application of dosimetric verification using film dosimetry as follows; film isocenter shift with optimization should be within +/-1 mm, and a ratio over 5% dose difference and average dose difference were less than 2%.

Hyperacute Radiation Effect on Cerebral Cortex after Local Gamma-irradiation in the Rat Brain

OBJECTIVE: We investigated the morphologic changes within 24 hours after a single gamma-irradiation in the rat brain. METHODS: Forty Sprague-Dawley rats were used. After a burr hole trephination on right parietal area, cerebral hemisphere was irradiated with 2Gy and 5Gy using iridium-192(192Ir), respectively. The effect was assessed at 4, 8, 12 and 24 hours after irradiation. The histological changes were scored following the detection of edema or disarray severity. TUNEL-positive cells exhibiting apoptotic morphology were counted in irradiated region. RESULTS: Cortical edema and disarray were initially showed at 4 or 8hour and almost all defined at 24hour after irradiation. And the injury was wedge shape. TUNEL-positive cells were minimal at 8hour after irradiation as the number of positive cells were 2.6+/-5.27(n=5) after 2Gy, and 0.8+/-0.84(n=5) after 5Gy. But, the number of apoptotic cells were increased markedly to 60+/-6.24 at 12hour after 2Gy and to 104+/-19.7 at 24hour after 5Gy. CONCLUSION: There were prominent morphologic changes immediately after gamma-irradiation. And, apoptosis was increased according to the time period. These findings implicate that brain irradiation induces rapid apoptotic change, which may play an important role in the pathogenesis of radiation-induced pathologic conditions.