Oncologic outcomes according to the level of disease burden in patients with metachronous distant metastases from uterine cervical cancer: a Korean Radiation Oncology Group study (KROG 18-10) / 부인종양

Objective@#This study aimed to evaluate the oncologic outcomes according to disease burden in uterine cervical cancer patients with metachronous distant metastases. @*Methods@#Between 2005 and 2015, 163 patients with metachronous distant metastases from uterine cervical cancer after receiving a definitive therapy were evaluated at seven institutions in Korea. Low metastatic burden was defined as less than 5 metastatic sites, whereas high metastatic burden was others. Each metastasis site was divided based on the lymph node (LN) and organs affected. The overall survival (OS) and progression-free survival (PFS) were assessed. Cox proportional hazards models, including other clinical variables, were used to evaluate the survival outcomes. @*Results@#The median follow-up duration was 22.2 months (range: 0.3–174.8 months). Para-aortic LNs (56.4%), lungs (26.4%), supraclavicular LNs (18.4%), and peritoneum (13.5%) were found to be the common metastasis sites. Among 37 patients with a single metastasis, 17 (45.9%) had LN metastases and 20 (54.1%) had organ metastases. The 1- and 2-year OS rates were 73.9% and 55.0%, respectively, whereas the PFS rates were 67.2% and 42.9%, respectively. SCC Ag after recurrence and high metastatic burden were significant factors affecting the OS (p=0.004 and p<0.001, respectively). Distant organ recurrence, short disease-free interval (≤2 years), and high metastatic burden were unfavorable factors for PFS (p=0.003, p=0.011, and p=0.002, respectively). @*Conclusion@#A favorable oncologic outcome can be expected by performing salvage treatments in selected patients with a long disease-free interval, low metastatic burden, and/or lymphatic-only metastasis.

Treatment outcomes of curative radiotherapy in patients with vulvar cancer: results of the retrospective KROG 1203 study

PURPOSE: We evaluated the prognostic factors and clinical outcomes of 56 patients with vulvar cancer treated with curative radiotherapy (RT) or concurrent chemoradiotherapy. MATERIALS AND METHODS: Overall survival (OS) and disease-free survival (DFS) were assessed retrospectively. Prognostic factors evaluated included age, International Federation of Gynecology and Obstetrics (FIGO) stage, TNM classification, tumor size, treatment modality, RT duration, and RT field. The association between the tumor human papillomavirus (HPV) status and survival was analyzed in 35 patients. RESULTS: During the median follow-up of 2.8 years (range, 0.3 to 18.9 years), 21 patients (37.5%) experienced treatment failure. Fifteen patients (27%) had local failure: nine (16%) local failure only, three (5%) locoregional failure, two (4%) local and distant failure, and one (2%) locoregional and distant failure. Of 56 patients, seven (13%) had persistent disease at the first follow-up at 2 months and all but one died within a year after completing RT. The 5-year OS and DFS were 51.6% and 44.0%, respectively. In multivariate analysis, clinical size > or =3 cm predicted a poor prognostic factor for DFS (p = 0.040) and age (> or =70 years) was poor prognostic for DFS (p = 0.032) and OS (p = 0.048). Patients with HPV-positive tumors tended to have better 5-year OS and DFS, but the differences were not significant statistically. CONCLUSION: Clinical size > or =3 cm was a significant prognostic factor for DFS. However, age was the most important prognostic factor for DFS and OS in patients treated with curative RT. Further studies are needed to determine which treatment should be considered for old age > or =70 years.

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.

A Retrospective Study of the Radiotherapy Care Patterns for Patients with Laryngeal Cancer and Comparison of Different Korean Hospitals Treated from 1998 through 1999 / 대한방사선종양학회지

PURPOSE: To investigate the care patterns for radiation therapy and to determine inter-hospital differences for patients with laryngeal carcinoma in Korea. MATERIALS AND METHODS: A total of 237 cases of laryngeal carcinoma (glottis, 144; supraglottis, 93) assembled from 23 hospitals, who underwent irradiation in the year of 1998 and 1999, were retrospectively analyzed to investigate inter-hospital differences with respect to radiotherapy treatment. We grouped the 23 hospitals based on the number of new patients annually irradiated in 1998; and designated them as group A (> or =900 patients), group B (> or =400 patients and <900 patients), and group C (<400 patients). RESULTS: The median age of the 237 patients was 62 years (range, 25 to 88 years), of which 216 were male and 21 were female. The clinical stages were distributed as follows: for glottis cancer, I; 61.8%, II; 21.5%, III; 4.2%, IVa; 11.1%, IVb; 1.4%, and in supraglottic cancer, I; 4.3%, II; 19.4%, III; 28.0%, IVa; 43.0%, IVb; 5.4%, respectively. Some differences were observed among the 3 groups with respect to the dose calculation method, radiation energy, field arrangement, and use of an immobilization device. No significant difference among 3 hospital groups was observed with respect to treatment modality, irradiation volume, and median total dose delivered to the primary site. CONCLUSION: This study revealed that radiotherapy process and patterns of care are relatively uniform in laryngeal cancer patients in Korean hospitals, and we hope this nationwide data can be used as a basis for the standardization of radiotherapy for the treatment of laryngeal cancer.

Statistical Errors in Papers Published in the Journal of the Korean Society for Therapeutic Radiology and Oncology / 대한방사선종양학회지

PURPOSE: To improve the quality of the statistical analysis of papers published in the Journal of the Korean Society for Therapeutic Radiology and Oncology (JKOSTRO) by evaluating commonly encountered errors. MATERIALS AND METHODS: Papers published in the JKOSTRO from January 2006 to December 2007 were reviewed for methodological and statistical validity using a modified version of Ahn's checklist. A statistician reviewed individual papers and evaluated the list items in the checklist for each paper. To avoid the potential assessment error by the statistician who lacks expertise in the field of radiation oncology; the editorial board of the JKOSTRO reviewed each checklist for individual articles. A frequency analysis of the list items was performed using SAS (version 9.0, SAS Institute, NC, USA) software. RESULTS: A total of 73 papers including 5 case reports and 68 original articles were reviewed. Inferential statistics was used in 46 papers. The most commonly adopted statistical methodology was a survival analysis (58.7%). Only 19% of papers were free of statistical errors. Errors of omission were encountered in 34 (50.0%) papers. Errors of commission were encountered in 35 (51.5%) papers. Twenty-one papers (30.9%) had both errors of omission and commission. CONCLUSION: A variety of statistical errors were encountered in papers published in the JKOSTRO. The current study suggests that a more thorough review of the statistical analysis is needed for manuscripts submitted in the JKOSTRO.

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.

Preliminary Report of the 1998~1999 Patterns of Care Study of Radiation Therapy for Esophageal Cancer in Korea / 대한방사선종양학회지

PURPOSE: For the first time, a nationwide survey in the Republic of Korea was conducted to determine the basic parameters for the treatment of esophageal cancer and to offer a solid cooperative system for the Korean Pattern of Care Study database. MATERIALS AND METHODS: During 1998~1999, biopsy-confirmed 246 esophageal cancer patients that received radiotherapy were enrolled from 23 different institutions in South Korea. Random sampling was based on power allocation method. Patient parameters and specific information regarding tumor characteristics and treatment methods were collected and registered through the web based PCS system. The data was analyzed by the use of the Chi-squared test. RESULTS: The median age of the collected patients was 62 years. The male to female ratio was about 91 to 9 with an absolute male predominance. The performance status ranged from ECOG 0 to 1 in 82.5% of the patients. Diagnostic procedures included an esophagogram (228 patients, 92.7%), endoscopy (226 patients, 91.9%), and a chest CT scan (238 patients, 96.7%). Squamous cell carcinoma was diagnosed in 96.3% of the patients; mid-thoracic esophageal cancer was most prevalent (110 patients, 44.7%) and 135 patients presented with clinical stage III disease. Fifty seven patients received radiotherapy alone and 37 patients received surgery with adjuvant postoperative radiotherapy. Half of the patients (123 patients) received chemotherapy together with RT and 70 patients (56.9%) received it as concurrent chemoradiotherapy. The most frequently used chemotherapeutic agent was a combination of cisplatin and 5-FU. Most patients received radiotherapy either with 6 MV (116 patients, 47.2%) or with 10 MV photons (87 patients, 35.4%). Radiotherapy was delivered through a conventional AP-PA field for 206 patients (83.7%) without using a CT plan and the median delivered dose was 3,600 cGy. The median total dose of postoperative radiotherapy was 5,040 cGy while for the non-operative patients the median total dose was 5,970 cGy. Thirty-four patients received intraluminal brachytherapy with high dose rate Iridium-192. Brachytherapy was delivered with a median dose of 300 cGy in each fraction and was typically delivered 3~4 times. The most frequently encountered complication during the radiotherapy treatment was esophagitis in 155 patients (63.0%). CONCLUSION: For the evaluation and treatment of esophageal cancer patients at radiation facilities in Korea, this study will provide guidelines and benchmark data for the solid cooperative systems of the Korean PCS. Although some differences were noted between institutions, there was no major difference in the treatment modalities and RT techniques.

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%.

Literature Analysis of Radiotherapy in Uterine Cervix Cancer for the Processing of the Patterns of Care Study in Korea / 대한방사선종양학회지

PURPOSE: Uterine cervix cancer is one of the most prevalent women cancer in Korea. We analysed published papers in Korea with comparing Patterns of Care Study (PCS) articles of United States and Japan for the purpose of developing and processing Korean PCS. MATERIALS AND METHODS: We searched PCS related foreign-produced papers in the PCS homepage (212 articles and abstracts) and from the Pub Med to find Structure and Process of the PCS. To compare their study with Korean papers, we used the internet site "Korean Pub Med" to search 99 articles regarding uterine cervix cancer and radiation therapy. We analysed Korean paper by comparing them with selected PCS papers regarding Structure, Process and Outcome and compared their items between the period of before 1980's and 1990's. RESULTS: Evaluable papers were 28 from United States, 10 from the Japan and 73 from the Korea which treated cervix PCS items. PCS papers for United States and Japan commonly stratified into 3~4 categories on the bases of the scales characteristics of the facilities, numbers of the patients, doctors. Researchers restricted eligible patients strictly. For the process of the study, they analysed factors regarding pretreatment staging in chronological order, treatment related factors, factors in addition to FIGO staging and treatment machine. Papers in United States dealt with racial characteristics, socioeconomic characteristics of the patients, tumor size (6), and bilaterality of parametrial or pelvic side wall invasion (5), whereas papers from Japan treated of the tumor markers. The common trend in the process of staging work-up was decreased use of lymphangiogram, barium enema and increased use of CT and MRI over the times. The recent subject from the Korean papers dealt with concurrent chemoradiotherapy (9 papers), treatment duration (4), tumor markers (8) and unconventional fractionation. CONCLUSION: By comparing papers among 3 nations, we collected items for Korean uterine cervix cancer PCS. By consensus meeting and close communication, survey items for cervix cancer PCS were developed to measure structure, process and outcome of the radiation treatment of the cervix cancer. Subsequent future research will focus on the use of brachytherapy and its impact on outcome including complications. These finding and future PCS studies will direct the development of educational programs aimed at correcting identified deficits in care.

Postoperative Radiotherapy in the Rectal Cancers Patterns of Care Study for the Years of 1998~1999 / 대한방사선종양학회지

PURPOSE: To conduct a nationwide survey on the principles in radiotherapy for rectal cancer, and produce a database of Korean Patterns of Care Study. MATERIASL AND METHODS: We developed web-based Patterns of Care Study system and a national survey was conducted using random sampling based on power allocation methods. Eligible patients were who had postoperative radiotherapy for rectal cancer without gross residual tumor after surgical resection and without previous history of other cancer and radiotherapy to pelvis. Data of patients were inputted to the web based PCS system by each investigators in 19 institutions. RESULTS: Informations on 309 patients with rectal cancer who received radiotherapy between 1998 and 1999 were collected. Male to female ratio was 59 : 41, and the most common location of tumor was lower rectum (46%). Preoperative CEA was checked in 79% of cases and its value was higher than 6 ng/ml in 32%. Pathologic stage were I in 1.6%, II in 32%, III in 63%, and IV in 1.6%. Low anterior resection was the most common type of surgery and complete resection was performed in 95% of cases. Distal resection margin was less than 2 cm in 30%, and number of lymph node dissected was less than 12 in 31%. Chemotherapy was performed in 91% and most common regimen was 5-FU and leucovorine (69%). The most common type of field arrangement used for the initial pelvic field was the four field box (Posterior-Right-Left) technique (65.0%), and there was no AP-PA parallel opposing field used. Patient position was prone in 81.2%, and the boost field was used in 61.8%. To displace bowel outward, pressure modulating devices or bladder filling was used in 40.1%. Radiation dose was prescribed to isocenter in 45.3% and to isodose line in 123 cases (39.8%). Percent delivered dose over 90% was achieved in 92.9%. CONCLUSION: We could find the Patterns of Care for the radiotherapy in Korean rectal cancer patients was similar to that of US national survey. The type of surgery and the regimen of chemotherapy were variable according to institutions and the variations of radiation dose and field arrangement were within acceptable range.

Development of Respiration Gating RT Technique using Moving Phantom and Ultrasound Sensor: a feasibility study / 대한방사선종양학회지

PURPOSE: In radiotherapy of tumors in liver, enough planning target volume (PTV) margins are necessary to compensate breathing-related movement of tumor volumes. To overcome the problems, this study aims to obtain patients' body movements by using a moving phantom and an ultrasonic sensor, and to develop respiration gating techniques that can adjust patients' beds by using reversed values of the data obtained. MATERIALS AND METHODS: The phantom made to measure patients' body movements is composed of a microprocessor (BS II, 20 MHz, 8K Byte), a sensor (Ultra-Sonic, range 3~3 m), host computer (RS232C) and stepping motor (torque 2.3 Kg) etc., and the program to control and operate it was developed. The program allows the phantom to move within the maximum range of 2 cm, its movements and corrections to take place in order, and x, y and z to move successively. After the moving phantom was adjusted by entering random movement data (three dimensional data form with distance of 2 cm), and the phantom movements were acquired using the ultra sonic sensor, the two data were compared and analyzed. And then, after the movements by respiration were acquired by using guinea pigs, the real-time respiration gating techniques were drawn by operating the phantom with the reversed values of the data. RESULTS: The result of analyzing the acquisition-correction delay time for the three types of data values and about each value separately shows that the data values coincided with one another within 1% and that the acquisition-correction delay time was obtained real-time (2.34x10-4 sec). CONCLUSION: This study successfully confirms the clinic application possibility of respiration gating techniques by using a moving phantom and an ultrasonic sensor. With ongoing development of additional analysis system, which can be used in real-time set-up reproducibility analysis, it may be beneficially used in radiotherapy of moving tumors.

External Beam Irradiation for Squamous Cell Carcinoma of the Maxillary Sinus / 대한방사선종양학회지

PURPOSE: Maxillary sinus cancers are usually locally advanced, and involve the structures around sinus, but the regional lymphatic spread is uncommon. Therefore, the local control of these cancers is important for their cure. We reviewed our experience of 55 patients with squamous cell carcinomas of the maxillary sinus, treated with radiation therapy, and looked for the role of radiation therapy in maxillary sinus cancers. MATERIALS AND METHODS: Between November 1982 and October 1999, 55 patients with squamous cell carcinomas of the maxillary sinus underwent either radiation therapy only, or combined with surgery or with concurrent chemoradiation therapy. All patients were restaged according to the 1997 AJCC staging systems. The T classifications of the tumors of the patients were as follows:1.8% (1/55) for T2, 81.8% (45/55) for T3 and 16.4% (9/55) for T4. Thirteen patients were diagnosed with lymph node involvement. With the surgical procedures, 12 patients were managed by biopsy only, 21 were resected by FESS (functional endoscopic sinus surgery) and 22 by partial/medial/total maxillectomies. The details of the treatments were as follows:8 patients were treated with radiation therapy only, 17 with a combination of FESS and radiation therapy, 22 with a combination of a maxillectomy and radiation therapy, 4 with a combination of preoperative radiation therapy and surgery, and 4 with concurrent chemoradiation therapy. The mean follow-up for all patients was 25 months, ranging from 2.8 to 125 months. RESULTS: The 4-year local control and survival rates for all patients were 45.5 and 33.3%, respectively. The 4-year local control and survival rates, due to the extent of surgery, were as follows:32.1, and 21.4 % for biopsy; 41.9, and 31.7% for FESS; and 56.8, and 52.7% for maxillectomy, respectively. Twenty-nine (52.7%) patients were not cured, and of these 29 patients, 23 (79.3%) patients had a local recurrence following treatment. CONCLUSION: This study has shown that the major failure sites following treatment to be the local regions, and that the completeness of surgery was important for improving the local control and survival of patients with squamous cell carcinoma of the maxillary sinus.

High-Dose-Rate Intraluminal Brachytherapy for Biliary Obstruction by Secondary Malignant Biliary Tumors / 대한방사선종양학회지

PURPOSE: To analyze the survival period, prognostic factors and complications of patients having undergone high-dose-rate intraluminal brachytherapy (HDR-ILB) as a salvage radiation therapy, while having a catheter, for percutaneous transhepatic biliary drainage (PTBD), inserted due to biliary obstruction caused by a secondary malignant biliary tumor. METHODS AND MATERIALS: A retrospective study was performed on 24 patients having undergone HDR- ILB, with PTBD catheter insertion, between December 1992 and August 2001. Their median age was 58.5, ranging from 35 to 82 years. The primary cancer site were the stomach, gallbladder, liver, pancreas and the colon, with 12, 6, 3, 2 and 1 cases, respectively. Eighteen patients were treated with external beam radiation therapy and HDR-ILB, while six were treated with HDR-ILB only. The total external beam, and brachytherapy radiations dose were 30~61.2 and 9~30 Gy, with median doses of 50 and 15 Gy, respectively. RESULTS: Of the 24 patients analyzed, 22 died during the follow-up period, with a median survival of 7.3 months. The 6 and 12 months survival rates were 54.2 (13 patients) and 20.8% (5 patients), respectively. The median survivals for stomach and gallbladder cancers were 7.8 and 10.2 months, respectively. According to the univariate analysis, a significant factor affecting survival of over one year was the total radiation dose (over 50 Gy) (p=0.0200), with all the patients surviving more than one year had been irradiated with more than 50 Gy. The acute side effects during the radiation therapy were managed with conservative treatment. During the follow-up period, 5 patients showed symptoms of cholangitis due to the radiation therapy. CONCLUSION: An extension to the survival of those patients treated with HDR-ILB is suggested compared to the median historical survival of those patients treated with external biliary drainage. A boost radiation dose could be effectively given, by performing HDR-ILB, which is a prognostic factor. In addition, the acute complications of radiation therapy were effectively controlled by conservative management, and it could be regarded as a safe treatment.

Endobronchial Brachytherapy of Advanced Non-small Cell Lung Carcinoma

PURPOSE: To evaluate the effect of high-dose-rate endobronchial brachytherapy for symptomatic relief, tumor response and overall survival of advanced non-small cell lung carcinoma (NSCLC). MATERIALS AND METHODS: Between July 1992 and July 2001, 37 patients with advanced NSCLC were analysed retrospectively. Group A patients (palliative aim, n=25) were treated using brachytherapy alone due to relapse after external beam radiation therapy (EBRT). Group B patients (curative aim, n=12) were treated using brachytherapy alone or combined EBRT due to untreated inoperable NSCLC or positive resection margin after radical resection. The dose per fraction was 3~6 Gy at a radius of 1cm from the center of the source and each patient received 2~3 fractions. The total dose of brachytherapy was 9~18 Gy (median 15 Gy). Each fraction separated by 1 week interval. RESULTS: Symptomatic relief was obtained for cough (58.3% & 72.7%), dyspnea (56.3% & 75%) and hemoptysis (86.7% & 100%) in group A and B, respectively. The tumor improvement on bronchoscopy was obtained for complete response (28% & 60%) and partial response (64% & 40%) in group A and B, respectively. Median overall survival was 7 and 17.2 months for Group A and B, respectively. In group A, mediastinal node metastasis (p=0.039) and Karnofsky performance scale (p=0.062) was independent prognostic factor by univariate analysis. After radical therapy, 7 symptomatic radiation pneumonitis, 4 hemoptysis and 1 pneumothorax were observed. CONCLUSION: Endobronchial brachytherapy was effective for symptomatic relief of hemoptysis. In curative aim, we think that survival improvement may be expected in some selected patients