[en] During the period from May 1980 through December 1983, 118 patients with esophageal carcinoma were treated at the Department of Radiology at the Hospital of Hyogo College of Medicine. Sixty-six out of the 118 patients had a primary radiotherapy. In 43 of the 66 (65 %), high-dose-rate intracavitary irradiation following external irradiation was performed as a boost therapy. A survival rate in 43 patients treated with high-dose-rate intracavitary irradiation was significantly higher (p < 0.0001) than that in the remaining 23 treated without high-dose-rate intracavitary irradiation. Especially in the UICC stage I group which was treated by high-dose-rate intracavitary irradiation, one-year and three-year survival rate were 70.7 % and 51.8 %, respectively. The method and technique of high-dose-rate intracavitary irradiation for esophageal carcinoma was established by the author and reported previously. The advantages of this treatment include no radiation exposure to the medical staff involved, less burdon for a patient and simplified care. Fistula induced by high-dose-rate intracavitary irradiation is a serious problem. However, since the safe range in total dosage was found to be 20 Gy or less, this treatment has been safely made. The data suggest that high-dose-rate intracavitary irradiation following external irradiation as a boost therapy is an effective modality for esophageal carcinoma. (author)

[en] Between May 1980 and March 1983, 31 patients with esophageal carcinoma were treated with a high-dose-rate remote controlled afterloading unit, as a boost therapy of the intracavitary irradiation following the external irradiation. The data of these patients were analyzed by the regression analysis which is one of the multivariate analyses, and following results were obtained. 1) Factors which affect local control achieved by intracavitary irradiation were the existence of deep ulcer or stenosis after external irradiation, age of the patient, dosage of intracavitary irradiation and tumor length. 2) The local control estimation index was determined by these five factors. Local control estimation index=1.38950-0.01571 x age+0.04517 x tumor length+0.62167 x stenosis* + 0.94811 x deep ulcer*-0.02969 x dosage of intracavitary irradiation. * Existence of stenosis/ulcer was represented by 1, and absence was represented by 0. 3) The local control estimation indices obtained in the above formula were then approved by applying internal samples, and also external samples. Indices of 0.5 or more mean local failure, and those of less than 0.5 mean possible local control. Examination was then made as to the local control estimation indices of another group of 30 patients who had been treated by external irradiation alone between November 1974 and April 1980. Comparison of the indices of the two groups showed the following results. 1) Rate of possible local control by external irradiation alone was 23%. 2) Rate of possible local control was increased up to 62% by using intracavitary irradiation following external irradiation. (author)

[en] Discussions are made on local control of 31 cases of esophageal carcinoma which were treated by external and intracavitary irradiation between May 1980 and March 1983. X-ray and endoscopic findings have been used for the image diagnosis. Before the begining of radiotherapy, types of esophageal carcinoma were determined from X-ray findings according to Borrmann's classification. There were 10 cases of types 1 and 2, and 21 cases of types 3 and 4. After completion of external and intracvitary irradiation, all 10 cases of types 1 and 2 were locally controlled. Of the 21 cases of types 3 and 4, 8 cases which developed stenosis or deep ulcer after external irradiation all failed in local control. The remaining 13 cases of types 3 and 4 were locally controlled except 2 by radiotherapy. (author)

[en] Treatment method of ion beam therapy was discussed. Ion beam treatment was compared with photon beam as to one and multi-portal treatment method. Dose distribution of ion beam is superior to that of photon beam and this results the difference between ion beam and photon beam as to the multi-portal treatment. Multi-portal treatment of ion beam makes the higher dosage to the tumor and results the shorter treatment period. (author)

[en] Purpose: With the aim of improving the results of treatment of esophageal cancer, we designed this multi-institutional, randomized trial to establish the optimal irradiation method in radical radiation therapy for esophageal cancer by clinically evaluating external irradiation alone and in combination with intraluminal brachytherapy. Methods and Materials: The study population consisted of patients with squamous cell carcinoma who were expected to be successfully treated with radical radiation therapy. The patients who could be given intraluminal brachytherapy at the end of external irradiation of 60 Gy were stratified into 2 groups. Patients assigned to receive external irradiation alone received boost irradiation of 10 Gy/week on a schedule similar to the previous one, and with the same or smaller irradiation field. Intraluminal brachytherapy was performed, as a rule, with the reference dose point set at a depth of 5 mm of the esophageal submucosa, and a total of 10 Gy was irradiated at a daily dose of 5 Gy, on a once-weekly schedule with low-dose-rate or high-dose-rate brachytherapy equipment. Results: A total of 103 patients were registered, 94 of whom were analyzable, with 8 ineligible, and 1 for whom complete information was unavailable. The overall cumulative survival rate was 20.3% at 5 years. The cause-specific survival rate was 31.8% at 5 years. The cause-specific survival rate at 5 years was 27% in the external irradiation alone group and 38% in intraluminal brachytherapy combined group. There was no significant difference between the 2 groups (p 0.385). However, in the patients with 5 cm or less tumor length, the cause-specific survival rate was 64% at 5 years in the intraluminal brachytherapy combined group, which showed a significant improvement over 31.5% in the external irradiation alone group (p = 0.025). In the patients with Stage T1 and T2 disease, cause-specific survival rates tended to be better in the intraluminal brachytherapy combined group than in the external irradiation alone group (p = 0.088). In the patients with more than 5 cm tumor length or Stage T3-4 disease, there were no significant differences between the two groups by treatment methods (p = 0.290). The incidence of early and late complications did not differ according to whether intraluminal brachytherapy was used. Conclusion: For the purpose of establishing the usefulness of intraluminal brachytherapy, further prospective randomized studies are necessary to evaluate the efficacy in tumors with short length and those with shallow invasion, or to assess the usefulness of intraluminal brachytherapy, as additional irradiation in large advanced tumors have been shown to have disappeared by diagnostic imaging after chemoradiotherapy with 60 Gy/6w external irradiation

[en] The histological findings of esophageal injury induced by intracavitary irradiation are reported. In the portion irradiated intracavitarily, denudation and regeneration were found in the epithelium, degenerative changes of small vessels and fibrotic changes were found in the submucosa, and fibrotic changes were also found in the muscle layers. Our data suggest that these characteristic changes correlate with the additional dosage given by intracavitary irradiation following external irradiation. (author)

[en] Absorbed dose of organs at risk in the 50% irradiated volume needs to be carefully monitored because there is high risk of radiation injury. This paper reports on the histogram of threedimensional volume dose of organs at risk, which is obtained by computer calculation of CT scans. In order to obtain this histogram, CT is first performed in the irradiation field. The dose in each pixel is then examined by the computer as to each slice. After the pixels of all slices in the organ at risk of the irradiated field are classified according to the doses, the number of pixels in the same dose class is counted. The result is expressed in a histogram. The histogram can show the differences of influence to organs at risk given by various radiation treatment techniques. Total volume dose of organs at risk after radiotherapy can also be obtained by integration of each dose of different treatment techniques. (author)

[en] This paper reports on the local recurrence in patients with esophageal carcinoma who received intracavitary irradiation following external irradiation without surgery. During the period from May 1980 through December 1984, 53 patients with esophageal carcinoma were primarily treated with intracavitary irradiation following external irradiation. Local failure was recognized in 20 patients including radiation induced fistulas in 4, residual tumors in 6 and local recurrences in 10. Clinical coarse of the patients with local recurrence cases were studied. The period of local recurrence after the completion of intracavitary irradiation was very short; in 9 of these 10 cases, local recurrence was recognized within six months. In contrast, one case with advanced esophageal carcinoma which is similar to the above group of patients was radically operated after the radical radiotherapy of intracavitary irradiation. He has no evidence of local recurrence now 2 years and 10 months after surgery. This suggests the effectiveness of combined therapy of surgery and radical radiation treatment including intracavitary irradiation. If operation is planned, it is recommended to be done within one month after radiotherapy because of rapid tumor regrowing. (author)

[en] Clinical data of 230 patients with prostate cancer that had been registered in Radiation Oncology Greater Area Database (ROGAD) from November 1992 to December 1998 was evaluated. The data of the patients with poorly differentiated histology (G3: 52%) in advanced stage (IV: 73%) were most commonly observed. External dose range to pelvis lymph node area or prostate gland for these patients was still immature in Japan, compared with those of the data of Patterns of Care Study in the United States. Estimated number of prostate cancer patients increased 2.4 times during the last 7 years. (author)

[en] We have reported the pulmonary injuries in mice following the whole lung irradiation. Irradiation was performed with 10 MeV electron beam up to 30 Gy in single fraction doses. Four and 8 weeks after irradiation, the pulmonary densities were measured using computed tomography (CT). The mean CT number of the lungs in the irradiated group was significantly higher than that in the non-irradiated group. (author)