PURPOSE: To generate the axial, coronal and sagittal images from conventional simulation images, as a preliminary study of broad-beam simulator CT. METHODS AND MATERIALS: Volumetric filtered back-projection was performed using 90 sheets of films from conventional simulator for every 4. gantry angle. Two mAs exposure condition for 120kVp beam quality at SFD 140cm was given to each film. Outside the silhouette portion was removed and scatter component was deconvolved before back-projection. RESULTS: The axial, the sagittal and the coronal images with same spatial resolutions over all direction could be obtained. But image quality was very poor. CONCLUSION: CT images could be obtained using broad-beam. Scatter deconvolution technique was effective for this reconstruction. The fact that same spatial resolutions over all direction tells us the possiblility of application of this technique to DRR or Simulator-CT. But the quality of image should be improved for clinical application practicaly.
Image Processing, Computer-Assisted*

PURPOSE: This study is to evaluate the efficacy of small bowel displacement system (SBDS) in post-operative pelvic radiation therapy (RT) of rectal cancer patients by measurement of small bowel volume included in the radiation fields receiving therapeutic dose. MATERIALS AND METHOD: Ten consecutive new rectal cancer patients referred to the department of Radiation Oncology of Samsung Medical Center in May of 1997 were included in this study. All patients were asked to drink Gastrographin before simulation and were laid prone for conventional simulation and CT scans with and without SBDS. The volume of opacified small bowel on CT scans, which was to be included in the radiation fields receiving therapeutic dose, was measured using picture archiving and communication system (PACS). RESULTS: The average small bowel volumes with and without SBDS were 176.0ml (5.2- 415.6ml) and 185.1ml (54.5- 434.2ml), respectively. The changes of small bowel volume with SBDS compared to those without SBDS were more than 10% decrease in three, less than 10% decreaseintwo,lessthan10%increaseinthree,andmorethan10%increaseintwopatients. CONCLUSION: No significant advantage of using SBDS in post-operative pelvic RT for rectal cancer patients has been shown by small bowel volume measurement using CT scan considering additional effort and time needed for simulation and treatment setup.
Diatrizoate Meglumine ; Humans ; Radiation Oncology ; Rectal Neoplasms* ; Tomography, X-Ray Computed

PURPOSE: Treatment of choice for uterine cervix cancer stage IIB is radiotherapy. We analyzed survivals, prognostic factors, patterns of failure and complications. MATERIALS AND METHODS: This is a retrospective analysis of 167 patients with stage IIB carcinoma of uterine cervix treated with curative external pelvic and high dose rate intracavitary radiotherapy at the Department of Therapeutic Radiology, Soonchunhyang University Hospital from August 1985 to August 1994. All the patients followed up from 3 to 141 months (mean 60 months) and age of patients ranged from 31 to 78 years at presentation (mean : 55 years). RESULTS: Overall complete response rate was 84%. The response rate for squamous cell carcimoma and adenocarcinoma were 86% and 60%, respectively. Overall 5-years survival rate and disease free survival rate was 62 and 59%, respectively. Mass size and treatment response were significant prognostic factors for survival. Pathologic type and parametrial involvement were marginally significants prognostic factors. Local failure was 43 cases, distant metastasis was 14 cases and local failure plus distant metastasis was 3 cases, and most of local failures occurred within 24 months, distant metastasis within 12 months after treatment. Twenty eight (16.8%) patients developed late rectal and urinary complications. There were tendency to increasing severity and frequency according to increased fractional dose and total (rectal and bladder) dose. CONCLUSIONS: Survival rate was significantly related to tumor size and radiotherapy response. Tumor size should be considered in the clinical staging. To increased survival and local control, clinical trials such as decreasing duration of radiotherapy or addition of chemotherapy is needed. To detect early recurrence, regular follow up after RT is important. Because total rectal and bladder doseaffected late complications, meticulous vaginal packing is needed to optimize dose of normal tissues and to decrease late complications.
Adenocarcinoma ; Cervix Uteri* ; Disease-Free Survival ; Drug Therapy ; Female ; Follow-Up Studies ; Humans ; Neoplasm Metastasis ; Radiation Oncology ; Radiotherapy* ; Recurrence ; Retrospective Studies ; Survival Rate ; Urinary Bladder ; Uterine Cervical Neoplasms

PURPOSE: Carcinomas arising in the gall bladder (GB) or extrahepatic biliary ducts are uncommon and generally have a poor prognosis. The overall 5- year survival rates are less than 10%. Early experiences with the external radiation therapy demonstrated a good palliation with occasional long-term survival. The present report describes our experience over the past decade with irradiation of primary carcinomas of the gallbladder and extrahepatic biliary duct. MATERIALS AND METHODS: From Feb. 1984 to Nov. 1995, thirty-three patients with carcinoma of the GB and extrahepatic biliary duct were treated with external beam radiotherapy with curative intent at our institution. All patients were treated with 4-MV linear accelerator and radiation dose ranged from 31.44Gy to 54.87Gy (median 44.25Gy), and three patients received additional intraluminal brachytherapy (range, 25Gy to 30Gy). Twenty-seven patients received a postoperative radiation. Among 27 patients, Sixteen patients underwent radical operation with curative aim and the rest of the patients either had bypass surgery or biopsy alone. In seventeen patients, adjuvant chemotherapy was used and eleven patients were treated with 5-FU, mitomycin and leucovorin. RESULTS: Median follow up period was 8.5 months (range 2-97 months). The overall 2-year and 5-year survival rates in all patients were 29.9% and 13.3% respectively. In patients with GB and extrahepatic biliary duct carcinomas, the 2-year survival rates were 34.5% and 27.8% respectively. Patients who underwent radical operation showed better 2-year survival rates than those who underwent palliative operation (43.8% vs. 20.7%). albeit, statistically insignificant (P>0.05). The 2-year survival rates in Stage I and II were higher than in Stage III and IV with statistical significance (P<0.05). Patients with good performance status in the beginning showed significantly better survival rates than those with worse status (P<0.05). The 2-year survival rates in combined chemotherapy group and radiation group were 40.5% and 22.6% respectively. There was no statistical differences in two groups (P>0.05). CONCLUSION: The survival of patients with relatively lower stage and/or initial good performance was significantly superior to that of others. We found an statistically insignificant trend toward better survival in patients with radical operation and/or chemotherapy. More radical treatment strategies, such as total resection with intensive radiation and/or chemotherapy may offer a better chance for cure in selective patients with carcinoma of gall bladder and extrahepatic biliary ducts.
Biopsy ; Brachytherapy ; Chemotherapy, Adjuvant ; Drug Therapy ; Fluorouracil ; Follow-Up Studies ; Gallbladder ; Humans ; Leucovorin ; Mitomycin ; Particle Accelerators ; Prognosis ; Radiotherapy* ; Retrospective Studies* ; Survival Rate ; Urinary Bladder*

PURPOSE: To investigate the role of adjuvant chemoradiotherapy in adenocarcinoma of the rectum, we retrospectively compared the treatment results between postoperative adjuvant radiotherapy alone and combined chemoradiotherapy. MATERIAL AND METHODS: From October 1989 to May 1994, 141 patients with rectal carcinoma were treated by postoperative adjuvant therapy in Yonsei Cancer Center. Sixty eight patients were treated by radiation therapy alone. Seventy three patients were treated by combined chemoradiotherapy. Radiation therapy was delivered with 10 MV linear accelerator, 180cGy fraction/5 days per week. Total radiation doses were 5400cGy in the postoperative radiotherapy alone group. Three to twelve cycles of Fluorouracil (mean dose 393.9mg/m2) with Leucovorin (20mg/m2) and 5040cGy of radiation were delivered in the combined chemoradiotherapy group. Third and 4th cycle of chemotherapy were administrated during the radiation treatment in the combined group. The median follow up was 38 months with a range of 3 to 81 months. RESULTS: The 5 year overall survival rate of radiation alone group and combined group were 60.1% and 66.3%, respectively. The 5 year disease free survival rate of radiation alone group and combined group were 54.2% and 65.5%, respectively. There was no significant difference of overall survival and disease free survival between RT alone group and combined group (P<0.05). But the 5 year Local failure free survival rate of combined group was significantly better than radiotherapy alone group (65.8% vs. 50.3%, P=0.04). CONCLUSION: There was no significant difference in overall survival, disease free survival, and distant metastasis free survival between postoperative adjuvant radiotheray alone group and combinded chemoradiotherapy group. Only the Local failure free survival rate was superior in the combined treatment group. These results confirm the radiosensitizing effect of the chemotherapeutic agent in the combined chemoradiotherapy treatment.
Adenocarcinoma* ; Chemoradiotherapy* ; Chemoradiotherapy, Adjuvant ; Disease-Free Survival ; Drug Therapy ; Fluorouracil ; Follow-Up Studies ; Humans ; Leucovorin ; Neoplasm Metastasis ; Particle Accelerators ; Radiation-Sensitizing Agents ; Radiotherapy ; Radiotherapy, Adjuvant ; Rectal Neoplasms ; Rectum* ; Retrospective Studies ; Survival Rate

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

PURPOSE: Although local recurrence rates of stomach cancer after radical surgery have been eported in the range of 30-70%, the role of postoperative adjuvant therapy has not been established. We report the result of radiotherapy in resected stomach cancer with positive surgical margin to elucidate the role of postoperative radiotherapy. MATERIALS AND METHODS: From June 1991 to August 1996, twenty five patients with positive surgical margins after radical gastrectomy were treated with postoperative radiotherapy and chemotherapy. Median dose of radiation was 55.8Gy and the range was 44.6-59.4Gy. Second cycle of chemotherapy was delivered concurrently with radiation and total number of six cycles were delivered. Twenty three had adenocarcinoma and the other two had leiomyosarcoma. The numbers of patients with stage IB, II, IIIA, IIIB, and IV were 1, 2, 11, 10 and 1 respectively. Positive margins at distal end of the stomach were in 17 patients and proximal in 5. The other three patients had positive margin at the sites of adjacent organ invasion. Minimum and median follow-up periods were 12 months and 18 months, respectively. RESULTS: Twenty-four of 25 patients received prescribed radiation dose and RTOG grade 3 toxicity of UGI tract was observed in 3, all of which were weight loss more than 15% of their pretreatment weight. But hematemesis, melena, intestinal obstruction or grade 4 toxicity were not found. Locoregional failure within the radiation field was observed in 7 patients, and distant metastasis in 10 patients. Sites of locoregional recurrences involve anastomosis/ remnant stomach in 3, tumor bed/duodenal stump in 3, regional lymph node in 1 patient. Peritoneal seeding occurred in 6, liver metastases in 2, and distant nodes in 2 patients. Four year disease specific survival rate was 40% and disease free survival was 48%. Median survival was 35 months and median disease free survival time was 26 months. Stages and radiation dose were not significant prognostic factors for locoregional failures. CONCLUSION: Although all patients in this study had positive surgical margins, locoregional failure rate was 28%, and 4 year disease specific survival rate was 40%. Considering small number of patients and relatively short follow-up period, it is not certain that postoperative radiotherapy lowered locoregional recurrences, but we could find a possibility of the role of postoperative radiotherapy in patients with high risk factors.
Adenocarcinoma ; Disease-Free Survival ; Drug Therapy ; Follow-Up Studies ; Gastrectomy ; Gastric Stump ; Hematemesis ; Humans ; Intestinal Obstruction ; Leiomyosarcoma ; Liver ; Lymph Nodes ; Melena ; Neoplasm Metastasis ; Radiotherapy* ; Recurrence ; Risk Factors ; Stomach ; Stomach Neoplasms* ; Survival Rate ; Weight Loss

PURPOSE: To evaluate survival rate and prognostic factors affecting survival of patients with esophageal cancer treated with concurrent chemoradiation. MATERIALS AND METHODS: Eligibility included biopsy proven invasive carcinoma of the cervical or thoracic esophagus, confined to esophagus and mediastinum with or without regional lymph node and supraclavicular lymph node, and ECOG performance status H0-H2. Patients received radiation therapy with 5940 cGy over 7 weeks and chemotherapy, consisted of 5-FU (1000 mg/m2/day in continuous infusion for 5 days, days 1 to 5 and days 29 to 33) and mitomycin C (8mg/m2 intravenous bolus at day 1). After concurrent chemoradiation, maintenance chemotherapy was followed with 5-FU (1000 mg/m2/day in continuous infusion for 5 days at 9th, 13th, and 17th weeks) and cisplatin (80mg/m2 intravenous bolus at the first day of each cycle). RESULTS: From November 1989 to November 1995, 44 patients were entered in this study. After treatment, complete response rate and partial response rate were 59% and 41%. Overall 1, 2, and 5-year survivals were 59%, 38%, and 9.6% (median 17 months). Prognostic factors affecting survival were response to treatment and T-stage. Among 26 complete responders, there were 6 local recurrences, 3 distant recurrences, 1 local and distant recurrence, and 2 unknown site recurrences. Acute and chronic complication rates with grade 3 or more were 20% and 13.6% and there was no treatment-related mortality. CONCLUSION: Concurrent chemoradiation, compared with historical control groups that treated with radiation alone, improved median survival and did not significantly increase treatment-related complications. Complete responders had longer survival duration than partial responders. Predominant failure pattern was local failure. So, efforts to improve local control should be proposed.
Biopsy ; Cisplatin ; Drug Therapy ; Esophageal Neoplasms* ; Esophagus ; Fluorouracil ; Humans ; Lymph Nodes ; Maintenance Chemotherapy ; Mediastinum ; Mitomycin ; Mortality ; Recurrence ; Survival Rate

PURPOSE: To determine the incidence and prognostic effect of p53 expression in patients with advanced supraglottic cancer. MATERIALS AND METHODS: Twenty-one cases of total 48 advanced supraglottic cancer patients who received postoperative adjuvant radiation therapy were evaluated by immunohistochemical staining employing p53 monoclonal antibody. RESULT: Three out of six stage III patients and four out of fifteen stage IV patients showed p53 expression without statistically significant difference (P=0.608). Five year survival rates are 93% in p53 negative, 86% in p53 positive patients and there was no significant difference (P=0.776). p53 expression does not show statistically significant correlation with primary tumor status (P=0.877), lymph node status (P=0.874) and age (P=0.64). CONCLUSION: There was no statistically significant correlation between traditionally known risk factors and p53 expression.
Humans ; Incidence ; Lymph Nodes ; Risk Factors ; Survival Rate

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.
Animals ; Feasibility Studies* ; Guinea Pigs ; Liver ; Microcomputers ; Radiotherapy ; Respiration* ; Ultrasonics ; Ultrasonography*