We have developed a 13.56 MHz radiofrequency interstitial hyperthermia system using thin needle electrodes for the treatment of malignant glioma. This article describes the heating apparatus, heating techniques, computer simulation system for thermal distribution and clinical trials performed on 61 patients with deepseated or surgically inaccessible malignant glioma. A single or double needle electrodes with a diameter of 1.0 mm were inserted into the tumor using stereotactic technique. The heating strategy was to heat the tumor (contrast-enhanced lesion on CT scan) margin up to 42.5 ÅãC in the eloquent region or 43.0 ÅãC in the noneloquent region. The heating condition was simulated by our computer simulation system preoperatively and confirmed by preliminary heating using continuous temperature measuring technique in each heating session. The heating was done 60 minutes in each session and repeated 3 or 4 times during two weeks in combination with conventional radiochemotherapy. The heating was done quite safely except minor complications occurred in a few cases. The response rate of the 34 heated primary tumors was 64.7% including 8 complete remission cases and much better than 22.8% in control group treated by radiochemotherapy alone. In conclusion, RF interstitial hyperthermia is a less invasive technique and can be a new powerful modality in multidisplinary treatment of malignant gliomas.

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Purpose: This study was designed to evaluate the proliferative response of epidermal growth factor (EGF) gene expression as an early indicator of late renal radiation damage.
Materials and Methods: EGF gene expression was measured in the irradiated left kidney of C3H/HeSlc mice using RT-PCR 24 hours after radiation doses of 9, 12, or 15 Gy. In a second experiment, the same radiation doses were administered to the right kidney plus the lower half of the left kidney. The partly irradiated left kidneys were harvested and EGF gene expression was measured. The irradiated whole right kidneys were subjected to immunohistochemical staining for EGF protein. In a third experiment, 12 Gy was administered to the right kidney plus the lower half of the left kidney. The mice underwent left nephrectomy 24 hours after radiation, and the EGF gene expression in the kidney was correlated with the blood urea nitrogen (BUN) level representing late renal functional damage.
Results: EGF expression increased in 1 of 10 control mice and in 9 of 10 mice that received 15 Gy. The extent of increase of EGF was dependent on radiation dose. In mice having an increased BUN level after irradiation, 7 of 10 had EGF positive irradiated kidneys. All six mice whose BUN levels were unchanged had EGF-negative irradiated kidneys. EGF protein staining was observed in tubule cells only, not in glomerular cells. The amount of EGF protein staining correlated with radiation dose to some extent.
Conclusions: EGF gene expression seems to be a very early indicator of late radiation damage to the kidney.

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This retrospective study reviewed 55 patients with adenoid cystic carcinoma of the head and neck who were treated with radiotherapy for primary sites between 1980 and 1998 The treatment modality consisted of radiotherapy combined with surgery in 44 patients and radiotherapy without surgery in 11 Chemotherapy was also administered to 9 operated and 6 unoperated patients The range of prescribed doses was 25-65 Gy (median 50 Gy) for patients who underwent surgery, and 60-70 Gy (median 65 Gy) for those who did not Local failure occurred in 16 patients (29%), and 20 (36%) developed distant metastasis, which were common types of failure Although not statistically significant different, local relapse free rates of early stage tumors were better than those of advanced stage tumors (p=0.08) The local relapse free rates were influenced by the primary sites (major vs minor salivary glands) (p=0.04) These factors, however, had no impact on survival Three patients developed recurrences in the skull base probably through perineural spread Neck failure was also uncommon type of recurrence, occurring in only two patients We also discuss elective irradiation to the neck nodes and the skull base.

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Purpose: This study investigated the treatment results and the prognostic factors of postoperative radiotherapy for stage pT1b-pT2b cervical cancer.
Materials and Methods: 245 patients with stage pTlb-pT2b squamous cell carcinoma of the uterine cervix treated with surgery and postoperative radiotherapy were analyzed. All patients received 40-64 Gy (median 49.6 Gy) external beam irradiation following radical or modified radical hysterectomy. Pathological factors and treatment-related factors were assessed for correlation with locoregional recurrence and survival. Correlation between treatment-related factors and late complications was also analyzed. Results: Median follow-up period was 62.5 months. The 5-year pelvic control (PC), progression free survival, and overall survival (OS) were 88.0%, 76.6%, and 79.0%, respectively. Recurrences were noted in 58 patients (23.7%). pT, pN, total external beam irradiation dose (TED), and overall external beam irradiation time (OET) were significant on PC, and pT, pN, surgical margin, stromal invasion, lymphovascular invasion, TED, interval between surgery and radiotherapy, OET, and combined use of intracavitary irradiation were significant on OS in univariate analysis. pN was found to be significant on OS and relatively significant on PC in multivariate analysis. The number of pelvic lymph node metastases significantly affected PC and OS. The 5-year intestinal, urinary, and leg edema complication rate were 10.9%, 6.0%, and 27.7%, respectively. TED was significant in univariate analysis, but no treatment-related factor was found to be significant in multivariate analysis.
Conclusion: The most important prognostic factor of postoperative radiotherapy for cervical cancer was pelvic lymph node metastasis (pN) in this study.

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To proceed with endobronchial brachytherapy with high dose rate Ir-192 safely, we have proposed a standard method of treatment. Since 1997, the Dokiya group of cancer research, entrusted by the Ministry of Health and Welfare, studied this topic.
By investigating the results of a questionnaire given to domestic institutions, guidelines for a treatment protocol were proposed as follows.
A. External beam radiotherapy of 40 Gy for 4 weeks and endobronchial brachytherapy with three fractions of 6 Gy for patients with roentgenographically occult lung cancer.
B. External beam radiotherapy of 60 Gy for 6 weeks and endobronchial brachytherapy with two or three fractions of 6 Gy for patients with lung cancer, with the intent of elimination of the tumor.
C. Endobronchial brachytherapy with one fraction of 10 Gy to patients for palliative intent.
At the time of treatment, an applicator should be used of which the source transfer tube is contained in the center of the lumen. The reference dose points are 10 mm from the source axis for the trachea and main bronchus, 5 mm from the source axis for the lobar bronchus, segmental, and sub-segmental bronchus.

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A report of a 48 year-old male with non-Hodgkin's lymphoma of the left parotid gland (clinical stage I EA, follicular medium-sized B cell type) is presented. He was solely treated with 30 Gy of radiation to the whole neck region, bilateral paraclavicular region and the left axilla, and 10.6 Gy boost was given to the primary lesion. Five months later, facial edema and serum LDH elevation developed suddenly. Relapse of the malignant lymphoma was suspected, but a whole body CT scan failed to show this. On the contrary, the CT scan showed a diffuse hypoattenuated area of the thyroid gland. In addition to positive antibodies, i.e, antithyroglobulin and antimicrosomal antibodies, total cholesterol and other serum markers also suggested hypofunction of the thyroid due to acute exacerbation of chronic thyroiditis. Immediately after hormonereplacement therapy, his symptoms disappeared and the abnormal serum data improved. Although the relationship between chronic thyroiditis and radiation injury has not been clearly demonstrated, it seems necessary to evaluate thyroid function before radiotherapy for head and neck tumors. Patients with chronic thyroiditis should be followed carefully after radiotherapy.

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The regular survey on radiotherapy resources in Japan at the end of 1999 was performed as a regular activity of JASTRO Database Committee. The census was taken by mailing a questionnaire to 737 radiotherapy facilities. Six hundred and fifty three (88.6%) questionnaires were returned, and 636 (86.3%) answers were available for analysis.
The number of newly registered patients who received radiotherapy in 1999 were 107, 150, it showed a steady increase.

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