PURPOSE: The main purpose of this study is to develop new payment rates for services of Radiation Oncology, considering costs of treating patients. MATERIAL AND METHODS: A survey of forty hospitals has been conducted in order to analyze the costs of treating patients. Before conducting the survey, we evaluated and reclassified the individual service items currently using as payments units on the fee-for-service reimbursement system. This study embodies the analysis of replies received from the twenty four hospitals. The survey contains informations about the hospitals' costs of 1995 for the reclassified service items on Radiation Oncology. After we adjust the hospital costs by the operating rate of medical equipment, we compare the adjusted costs with the current payment rates of individual services. RESULTS: The current payment rates were 5.05-6.58 times lower than the adjusted costs in treatment planning services, 2.22 times lower in block making service, 1.57-2.86 times lower in external beam irradiation services, 3.82-5.01 times lower in intracavitary and interstitial irradiation and 1.12- 2.55 times lower in total body irradiation. CONCLUSION: We could conclude that the current payment system on Radiation Oncology does not only reflect the costs of treating patients appropriately but also classify the service items correctly. For an example, when the appropriate costs and classification are applied to TBI, the payment rates of TBI should be increased five times more than current level.
Classification* ; Fee-for-Service Plans ; Hospital Costs ; Humans ; Radiation Oncology* ; Whole-Body Irradiation

PURPOSE: Secondary electrons generated by interaction between primary X-ray beam and block tray in megavoltage irradiation, result in excess soft radiation dose to the surface layer. To reduce the surface dose from the electron contamination, electron filters were attached under the tray when a customized block was used. MATERIALS AND METHODS: Cu, Al or Cu/Al combined plate with different thickness was used as a filter and the surface dose reduction was measured for each case. The measurement to find optimal filter was performed with 10cm x 10cm field size and 78.5cm source to surface distance. The measurement points are positioned with 2mm intervals from surface to maximum build-up point. To acquire the effect of field size dependence on optimal electron filter, the measurement was performed from 4cm x 4cm to 25cm x 25cm field sizes. RESULTS: The surface dose was slowly increased by increasing irradiation field but rapidly increased beyond 15cm x 15cm field size. Al plate was found to be inadequate filter because of the failure to have surface dose kept lowering than the dose of deep area. Cu 0.5mm plate and Cu/Al= 0.28mm/1.5mm combined plate were found to be optimal filters. By using these 2 filters, the absorbed dose to the surface layer was effectively reduced by 5.5%, 11.3%, and 22.3% for the field size 4cm x 4cm, 10cm x 10cm, and 25cm x 25cm, respectively. CONCLUSION: The surface dose attributable to electron contamination had a dependence on field size. The electron contamination was increased when tray was used. Specially the electron contamination in the surface layer was greater when the larger field was used. 0.5mm Cu plate and Cu/Al=0.28mm/1.5mm combined plates were selected as optimal electron filters. When the optimal electron filter was attached under the tray, excessive surface dose was decreased effectively. The effect of these electron filters was better when a larger field was used.

PURPOSE: The Dual-Energy Quantitative Computed Tomography(DEQCT) was compared with bone equivalent K2HPO4 standard solution and ash weight of animal cadaveric trabecular bone in the measurement of bone mineral contents(BMC). METHOD AND MATERIALS: The attenuation coefficient of tissues highly depends on the radiation energy, density and effective atomic number of composition.The bone mineral content of DEQCT in this experiments was determined from empirical constants and mass attenuation coefficients of bone,fat and soft tissue equivalent solution in two photon spectra.In this experiments, the BMC of DEQCT with 80 and 120kVp X rays was compared to ash weight of animal trabecular bone. RESULTS: We obtained the mass attenuation coefficient of 0.2409, 0.5608 and 0.2206 in 80kVp, and 0.2046, 0.3273 and 0.1971cm2/g in 120kVp X-ray spectra for water, bone and fat equivalent materials, respectively.The BMC with DEQCT was acomplished with empirical constants K1=0.3232, K2=0.2450 and mass attenuation coefficients has very closed to ash weight of animal trabecular bone. The BMC of empirical DEQCT and that of manufacturing DEQCT were correlated with ash weight as a correlation r=0.998 and r=0.996, respectively. CONCLUSION: The BMC of empirical DEQCT using the experimental mass attenuation coefficients and that of manufacture have showed very close to ash weight of animal trabecular bone.
Animals ; Bone Density* ; Cadaver ; Water

PURPOSE: To evaluate the loss of bone mineral contents(BMC) in lumbar spine within the radiation field for cervical cancer treatment, BMC in the irradiated patient group was compared with that of a normal control group. METHOD AND MATERIALS: Measurements of BMC in the trabecular bone in lumbar spines(L3-L5) were performed in the both patient and normal control groups. Investigators used dual-energy quantitative computerized tomography(DEQCT) using photon energy of 120 and 80kVp. The numbers of patient and control groups were 43 in each with age distribution of fifth to seventh decade of women. The numbers of control group were 22 in fifth, 10 in sixth, and 11 in seventh decade, those of patient group were 14 in fifth, 14 in sixth, and 15 in seventh decade of women. The radiation field was extended to L5 spine for pelvic irrdiation with 45-54Gy of external radiation dose and 30Gy of high dose rate brachytherapy in cervical cancer. RESULTS: The BMC is decreased as increasing age in both control and patient groups. BMC in lumbar spine of patient group was decreased by about 13% to 40% maximally. The BMC of L3 and L4 a region that is out of a radiation field for the patient group demonstrated 119.5+/-30.6, 117.0+/-31.7 for fifth, 83.3+/-37.8, 88.3+/-46.8 for sixth and 61.5+/-18.3, 56.2+/-26.6mg/cc for seventh. Contrasted by the normal control group has shown 148.0 +/-19.9, 153.2+/-23.2 for fifth, 96.1+/-30.2, 105.6+/-26.5 for sixth and 73.9+/-27.9, 77.2+/-27.2mg/cc for seventh decade, respectively. The BMC of patient group was decreased as near the radiation field, while the lower lumbar spine has shown more large amounts of BMC in the normal control group. In particular, the BMC of L5 within the radiation field was significantly decresed to 33%, 31%, 40% compared with the control group of the fifth, sixth and seventh decades, respectively. CONCLUSION: The pelvic irradiation in cervical cancer has much effected on the loss of bone mineral content of lumbar spine within the radiation field, as the lower lumbar spine has shown a smaller BMC in patient group with pelvic irradiation in contrast to that of the normal control groups.
Age Distribution ; Bone Density* ; Brachytherapy ; Female ; Humans ; Research Personnel ; Spine* ; Uterine Cervical Neoplasms*

PURPOSE: Radiation pneumonitis is one of the complications caused by radiation therapy that includes a portion of the lung tissue. The severity of radiation induced pulmonary dysfunction depends on the irradiated lung volume, total dose, dose rate and underlying pulmonary function. It also depends on whether chemotherapy is done or not. The irradiated lung volume is the most important factor to predict the pulmonary dysfunction in breast cancer patients following radiation therapy. There are some data that show the irradiated lung volume measured from CT scans as a part of treatment planning with the tangential beams. But such data have not been reported in Korea. We planned to evaluate the irradiated lung volume quantitatively using CT scans for the breast tangential field and search for useful factors that could predict the irradiated lung volume. MATERIALS AND METHODS: The lung volume was measured for 25 patients with breast cancer irradiated with tangential field from Jan.1995 to Aug.1996. Parameters that can predict the irradiated lung volume included; (1) the perpendicular distance from the posterior tangential edge to the posterior part of the anterior chest wall at the center of the field (CLD); (2) the maximum perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall (MLD); (3) the greatest perpendicular distance from the posterior tangential edge to the posterior part of anterior chest wall on CT image at the center of the longitudinal field (GPD); (4) the length of the longitudinal field (L). The irradiated lung volume(RV), the entire both lung volume(EV) and the ipsilateral lung volume(IV) were measured using dose volume histogram. The relationship between the irradiated lung volume and predictors was evaluated by regression analysis. RESULTS: The RV is 61-279cc (mean 170cc), the RV/EV is 2.9-13.0% (mean 5.8%) and the RV/IV is 4.9-29.6% (mean 12.2%). The CLD, the MLD and the GPD are 1.9-3.3cm, 1.9-3.3cm and 1.4-3.1cm respectively. The significant relations between the irradiated lung volume such as RV, RV/EV, RV/IV and parameters such as CLD, MLD, GPD, L, CLDxL, MLDxL and GPDxL are not found with little variances in parameters. The RV/IV of the left breast irradiation is significantly larger than that of the right but the RV/EVs do not show the differences. There is no symptomatic radiation pneumonitis at least during 6 months follow up. CONCLUSION: The significant relationship between the irradiated lung volume and predictors is not found with little variation on parameters. The irradiated lung volume in the tangential field is less than 10% of entire lung volume when CLD is less than 3cm. The RV/IV of the left tangential field is larger than that of the right but there was no significant differences in RV/EVs. Symptomatic radiation pneumonitis has not occurred during minimum 6 months follow up.
Breast Neoplasms ; Breast* ; Drug Therapy ; Follow-Up Studies ; Humans ; Korea ; Lung* ; Radiation Pneumonitis ; Thoracic Wall ; Tomography, X-Ray Computed

PURPOSE: We analyzed the survival and failure patterns of cervix cancer patients treated with irradiation alone to evaluate our treatment method and to compare with the others. METHODS AND MATERIALS: Two hundred and twenty cervical cancer patients, Stage IB, IIA, and IIB who completed the planned treatment between May 1987 and December 1991 were analyzed retrospectively. The Stage IB patients were restaged to the Stage IB1 and IB2 by the recently revised FIGO classification. Patients were treated with a combination of external irradiation and the intracavitary brachytherapy. Determination of the tumor control was done at the time of 6 months postirradiation. The follow-up time was ranged from 3 to 115 months and the mean was 62 months and the follow-up rate was 93.6%(206/220). RESULTS: The overall 5-year survival rate of Stage IB1(N=50), IB2(N=15), IIA(N=58), and IIB(N=97) was 94%, 87%, 69%, and 56%, respectively. In the univariate analysis of prognostic factors,stage(0.00), initial Hg level (p=0.00), initial TA-4(tumor-associated) antigen level(p=0.02), initial CEA level(p=0.02), barrel-shaped tumor(p=0.02), whole cervical involvement (0.00), pelvic lymphadenopathy(LAP) in CT(p=0.04), and post-irradiation adjuvant chemotherapy(p=0.00) were statistically significant in survival analysis. In a while, multivariate analysis showed that the stage was the most powerful prognostic indicator and the post-irradiation chemotherapy factor also showed the statistical significance. The overall local control rate was 81% and by the stage, 100% in Stage IB1, 86.7% in Stage IB2, 84.5% in Stage IIA, and 68.1% in Stage IIB, respectively. The overall tumor recurrence rate was 15.5%(27/174) and by the stage, 8%(4/50) in Stage IB1, 0%(0/13) in Stage IB2, 22.4%(11/49) in Stage IIA, and 19.4%(12/62) in Stage IIB, respectively. CONCLUSIONS: We obtained the similar treatment results to the other's ones in early stage cervical cancer patients. But in Stage IIB, the local control rate was lower than that of the other institutes and also the survival was poorer. So it seems to be necessary to reevaluate the treatment method in advanced cervical cancer patients.
Academies and Institutes ; Brachytherapy ; Cervix Uteri* ; Classification ; Drug Therapy ; Female ; Follow-Up Studies ; Humans ; Multivariate Analysis ; Radiotherapy ; Recurrence ; Retrospective Studies ; Survival Rate ; Uterine Cervical Neoplasms

PURPOSE: To evaluate the effect of postoperative adjuvant radiation therapy and chemotherapy on the survival, pattern of failure and complication for locally advanced rectal carcinoma MATERIALS AND METHODS: From October 1992 to September 1995, twenty eight patients with rectal carcinoma were treated by postoperative adjuvant radiation therapy and chemotherapy. Radiation therapy was delivered with 6MV and 15MV linear accelerator, 180cGy fractions 5 day per week. Total radiation doses were 5040cGy in B2+3 and 5580cGy in C2+3. Within 4 weeks after radical surgery, 5-FU(400mg/m2/day) and Leucovorin(20mg/m2/day) were administered by intravenous injection for 4 days during the first and fifth week of radiation therapy. The median follow up was 19 months with a range 2 to 47 months. RESULTS: The 2 year overall survival and disease free survival rates were 78.6% and 70.8%, respectively. The 2 year overall survival was 93.0% in B2+3 and 76.2% in C2+3(p=0.11). The 2 year disease free survival was 79.4% in B2+3 and 69.2% in C2+3(p=0.13). The overall failure rate was 21.4%(6/28) including 10.7%(3/28) locoregional recurrence, 3.6%(1/28) distant metastasis and 7.1%(2/28) locoregional recurrence with distant metastasis. The overall locoregional recurrence rate was 17.9%(5/28). The 2 year locoregional recurrence rates were 13.3%(2/15) and 23.1%(3/13) for respectively for B2+3 and C2+3. The difference between the locoregional recurrence of B2+3 and C2+3 patients was not significant(p=0.07). Complications developed in 13 patients(46.4%), including 8 dermatitis, 7 loose stool, 6 leukopenia, 4 tenesmus, 2 diarrhea. In Univariate analysis, there was no statistically significant factor except for tumor grade in locoregional recurrence, disease free survival and overall survival rate(p=0.04, 0.05, 0.04). CONCLUSION: This study suggests that postoperative adjuvant radiation therapy and chemotherapy is effective in patients with locally advanced rectal cancer. Therefore these results need to be confirmed with a long term follow-up and larger number of patients with the further clinical trials including prospective controlled studies.
Dermatitis ; Diarrhea ; Disease-Free Survival ; Drug Therapy* ; Follow-Up Studies ; Humans ; Injections, Intravenous ; Leukopenia ; Neoplasm Metastasis ; Particle Accelerators ; Rectal Neoplasms* ; Recurrence

PURPOSE: Radical gastrectomy is main treatment of gastric cancer. But the result is not satisfactory with surgery alone. Most of pattern of failure remain locoregional recurrence. To improve 5 year survival postoperative chemotherapy with or without radiotherapy has been used. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. MATERIAL AND METHOD: From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adjuvant radiotherapy with 36Gy or more were evaluated. Median age was 60 years(range 28-66 yrs). Patients were followed from 3 to 133 months with median follow up of 48 months. Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively. Chemotherapy was given to all patients except two. RESULTS: Five-year overall survival and disease-free survival rate were 36.6% and 33.6%, respectively. Prognostic factor affecting survival were assessed. High ratio of involved/dissected lymph node, signet ring histology showed poor prognosis with statistical significance. Presence of residual tumor after surgery, stageIV, split course of radiation therapy, age, number of involved lymph node, number of lymph node dissection and grade of tumor affected survival without statistical significance. Type of chemotherapy did not affect survival.Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and E-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six patients(8.8%) had weigh loss more than 10%. CONCLUSION: Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high. Five-year surival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival. To evaluate role of radiation prospective randomized study employing chemotherapy alone and chemotherapy plus radiation is necessary. Futhermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored.
Adenocarcinoma ; Disease-Free Survival ; Drug Therapy ; Follow-Up Studies ; Gastrectomy ; Gastric Stump ; Humans ; Leukopenia ; Lymph Node Excision ; Lymph Nodes ; Neoplasm Metastasis ; Neoplasm, Residual ; Omentum ; Peritoneum ; Prognosis ; Radiotherapy* ; Radiotherapy, Adjuvant ; Recurrence ; Retrospective Studies ; Stomach Neoplasms*

PURPOSE: This study was to evaluate survival, failure patterns, and prognostic factors of patients with metastatic neck nodes from an unknown primary site. MATERIALS AND METHODS: A retrospective analysis was done for 35 patients with metastatic neck nodes from an unknown primary site who were treated with radiation from January 1986 to September 1994. There were 26 male and 9 female patients. Patients' age ranged from 41 to 74 years (median 58 years). Stage distribution showed 1 patient with N1, 27 with N2, and 7 with N3. Amomg these patients, 7 with a supraclavicular lymph node alone were included. The histologic type was squamous cell carcinoma in 22 patients, undifferentiated carcinoma in 6, adenocarcinoma in 4. We could not classify a histologic type in 3 patients. Radiation therapy alone was done in 7 patients, induction chemotherapy and radiation therapy in 10, and postoperative radiation therapy in 18. Radiation therapy fields included both neck and pharyngeal axis, and total dose was 40-95.6Gy (median 60Gy) using 6MV X-ray. Chemotherapy consisted of 2 cycles of 5-fluorouracil and cisplatin. Surgical methods were a radical neck dissection in 17 patients and an excisional biopsy in 1 patient. Follow-up time ranged from 2 to 95 months, median 15 months. RESULTS: Overall and disease-free survival rate at 4 years were 33.4% and 33.9%, respectively. The factors associated with the overall survival rate were histologic type(adenocarcinoma vs. non-adenocarcinoma, p=0.0005), N stage(p=0.023), and the site of involved nodes(p=0.021). According to the treatment modality, 2-year survival rate was 14.3% in radiation therapy alone group, 35.8% in induction chemotherapy and radiation thrapy, and 37.5% in postoperative radiation therapy(Fig. 4, p=0.05), which might be due to the difference of N stage distribution. The failure patterns were analyzed in 25 patients with a complete response to the treatment. Local failure wasnoted in 7 patients, distant metastases in 6, local failure and distantmetastases in 1. Excluding the 7 patients with supraclavicular lymph node metastaes alone, 28%(7/25) of the patients had distant metastases. During the follow-up period, 11%(3/35) of the patients showed a delayed primary site, 1 in oral cavity, 1 in nasopharynx, and 1 in hypopharynx. CONCLUSION: N stage, the site of involved node, and histologic type were associated with survival rate. In patients with advanced N stage, curative rather than inductive chemotherapy is needed because combined surgery and radiation therapy achieved poor results and considerable patients developed distant metastases.
Adenocarcinoma ; Axis, Cervical Vertebra ; Biopsy ; Carcinoma ; Carcinoma, Squamous Cell ; Cisplatin ; Disease-Free Survival ; Drug Therapy ; Female ; Fluorouracil ; Follow-Up Studies ; Humans ; Hypopharynx ; Induction Chemotherapy ; Lymph Nodes ; Male ; Mouth ; Nasopharynx ; Neck Dissection ; Neck* ; Neoplasm Metastasis ; Radiotherapy* ; Retrospective Studies ; Survival Rate

PURPOSE: To evaluate the roles of conventional radiotherapy alone or with neoadjuvant chemotherapy for tonsillar carcinomas and any prognostic factors affecting survivals by retrospective analysis. MATERIALS AND METHODS: Thirty four patients received radical radiotherapy for tonsillar carcinomas from Nov. 1985 to Dec. 1993. Of them, 16 patients were treated by conventional radiotherapy alone and the other 18 patients were received radiotherapy with 1 to 3 cycles of neoadjuvant chemotherapy of cisplatin and 5-fluorouracil or pepleomycin. Radiotherapy was performed by 6MV X-ray with daily fraction of 1.8Gy and the range of primary tumor doses was 55.0-86.4Gy(median 66.6Gy), and that of clinically positive nodal doses was 55.8-90Gy(median 69.7Gy). RESULTS: Overall 5-year actuarial survival rate (5YSR) was 32%. The 5YSRs in stage I+II(n=8), III(n=13) and IV(n=13) were 47%, 29% and 25%, respectively(p=0.33). The 5YSRs in T2(n=13), T3(n=10) and T4 (n=7) were 38%, 27% and 0%, respectively and 3 of 4 patients of T1 are alive with NED at 25, 45, 53 months respectively with statistical significance of the trend in survivals among the four T-stages(p=0.01), and those of node negative(n=14) vs node positive patients(n=20) were 31% vs 32%, respectively(p=0.85). There was no significant survival difference between radiotherapy alone group and with neoadjuvant chemotherapy group(22% vs. 38%, p=0.24). The 5YSRs of 21 patients of primary tumor extension to adjacent sites and the other 13 patients of tonsillar proper site were 28% and 38%, respectively but the difference was not significant statistically(p=0.62). There was a statistically significant difference in 5YSRs between the groups of the patients who received radiotherapy in less than 61days vs more than 60days(60% vs. 18%, p=0.027). All living patients without any tumor progression(n=11) had suffered from serious late sequelae such as xerostomia, edentia, dental caries and one patient had the osteoradionecrosis of mandible. On univariate analysis, the duration of radiotherapy and T-stage were the significant prognostic factors affecting 5YSR. On multivariate analysis, also the duration of radiotherapy was the only significant prognostic factor(p=0.01). CONCLUSION: There was no survival difference between the radiotherapy alone and with neoadjuvant chemotherapy groups. Although it was a retrospective study, the role of conventional radiotherapy alone could be effective as the local treatment modality only for the early stage of tonsillar carcinomas. But for the purpose of more improved survivals and better quality of lives of living patients, other altered fractionation such as hyperfractionated radiotherapy with shorter treatment time and smaller fraction size rather than conventional radiotherapy might be beneficial and these prospective studies are needed.
Cisplatin ; Dental Caries ; Drug Therapy ; Fluorouracil ; Humans ; Mandible ; Multivariate Analysis ; Osteoradionecrosis ; Peplomycin ; Radiotherapy* ; Retrospective Studies ; Survival Rate ; Tonsillar Neoplasms ; Xerostomia