The influence of several cancer-related genes, myc, fos, jun, ras, raf, mos, cot, src, erb B, bcl-2, RB and p53, on radiosensitivity has been shown by transfection studies. This review focuses on the functions of growth arrest, DNA repair and apoptosis regulated by these cancer-related genes. Resistance to apoptosis has emerged as a major category of radiation sensitivity. In the near future, it might be clear which of the cancer-related genes acts in an important role in apoptosis pathway after irradiation. In addition, there is no direct evidence in the activation of DNA repair during the cell cycle arrest. Therefore, identification of factors directly acting on radiation sensitivity will offer new strategies in cancer predictical assay using biopsied tumor specimens in radiotherapy. Further studies are must to be carried out for detection of common mutations in cancer-related genes for predictical assay and the potential for induction of apoptosis by radiotherapy and genetherapy.

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Results of²²⁶Ra brachytherapy for 47 patients with T1 and T2 tongue carcinoma were estimated and the clinical implication of ploidy and potential doubling time (Tpot) was discussed. Dose estimation was performed by using the dose distribution obtained from computerized dose calculators, considering Paterson-Parker's system. For T2 carcinoma, external beam irradiation (20-50 Gy) was carried out in the 12 patients and intensive chemotherapy was combined in the 16 patients. Ipsilateral neck dissection was performed for 3 out of the 4 T2N1 patients. Ploidy was analysed with flow cytometer and Tpot was obtained from in vitro labeling with bromodeoxyuridine and immunohistochemical stain. A five-year cause specific survival was 92% for T1 and 91% for T2, respectively. A five-year tumor control probability was 86% for T1 and 88% for T2, respectively. Combined intensive chemotherapy and external beam irradiation showed poorer treatment results than those without the modalities.“Down-staging”with the preceding combined modalities before²²⁶Ra brachytherapy possibly had a risk to cause a geographical miss of needle implant. The significant role of Tpot was unclear. Ploidy of the tumors showed some predictive potential for the therapeutic results and the frequency of occult neck node metastasis. Optimization of brachytherapy based on the computerized dose estimation and the clinical application of biological predictors of tumors including ploidy should be considered for the treatment of tongue carcinoma.

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Introduction: A lot of clinical data about stereotactic radiotherapy (SRT) werereported, however, standard fractionated schedules were not shown. In this paper, our clinical results of SRT, 3 fractions of IOGy, are reported.
results of SRT, 3 fractions of IOGy, are reported.
Materials and Methods: Between February 1992 and March 1995, we treated 41 patients with 7 arteriovenous malformations and 41 intracranial tumors using a stereotactic technique implemented by a standard 10MV X-ray linear accelerator. Average age was 47.4 years (range 3-80 years) and average follow-up time was 16.7 months (range 3.5-46.1 months). The patients received 3 fractions of IOGy for 3 days delivered by multiple arc narrow beams under 3 cm in width and length. A threepieces handmade shell was used for head fixation without any anesthetic procedures. Threedimensional treatment planning system (Focus) was applied for the dose calculation. All patients have received at least one follow-up radiographic study and one clinical examination.
Results: In four of the 7 patients with AVM the nidus has become smaller, 9 of the 21 patients with benign intracranial tumors and 9 of the 13 patients with intracranial malignant tumors have shown complete or partial response to the therapy. In 14 patients, diseases were stable or unevaluable due to the short follow-up time. In 5 patients (3 with astrocytoma, 1 each with meningioma and craniopharyngioma), diseases were progressive. Only 1 patient with falx meningioma had minor complication due to the symptomatic brain edema around the tumor.
Conclusion: Although, further evaluation of target control (i.e. tumor and nidus) and latenormal tissue damage is needed, preliminary clinical results indicate that SRT with our methods is safe and effective.

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Many reports concerning radiation therapy for brain metastasis have been published, and which of the various methods urged by these reports provide optional control is still controversial. According to developing diagnosis of metastasis in CNS, therapeutic problems should be referred. We reviewed 67 patients with small cell lung cancer and brain metastasis who underwent brain irradiation (Ave. 47Gy/5W), and all 15 patients with brain relapse after the irradiation. Relapsing patterns in this clinical setting were divided into local regrowth in the same lesions and re-metastasis (reseeding) in other regions, by reviewing follow up CT and MRI studies.
(1) Total survival among 15 patients with brain relapse and 52 without relapse was longer in the former cases than the later: 1-, and 2-year survival (47/19%, 13/8%) and MST (10.8/5.7months), from the initial brain irradiation. The concerned significant factors limited in younger age, low value of LDH and improvement of NF.
(2) Of the 15 patients with brain relapse, 4 developed local regrowth and 11 did re-metastasis. The period of remission since brain irradiation were 172±94.4 and 393±281 days, respectively. Lower number of brain metastasis and lower value of LDH were shown in re-metastasis patients.
(3) At the time of brain relapse, 11 patients had recurrence of carcinomatous meningitis. 4 patients were treated with whole brain re-irradiation. All patients died of cancer, including 12 of relapsing CNS diseases and 3 of primary lesion and hepatic metastasis. Leukoencephalopathy developed in 2 patients. Survival since the brain relapse was 2 to 238 days without significant difference in cases of local regrowth and re-metastasis. According to our data on relapsing pattern of brain metastasis after conventional fractionated brain irradiation with an objective dose of 50Gy, 75% of brain relapse were re-metastasis, we appreciate this irradiation for initial brain metastasis if limited to the brain.

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Between 1982 and 1994, 70 patients with hypopharyngeal cancer were treated withsurgery at Saitama Cancer Center. Twenty-two of these patients received post-operative radiotherapy. We studied on these post-operative case with regard to radiotherapeutic indication for retropharyngeal space. Three patients in stage III, and 19 patients in stage IV were treated. The 3-year cause specific survival and loco-regional relapse free survival rates were 27.3% and 33.7%, respectively. Reconstructive cervical esophagus, oropharyngeal wall, and retropharyngeal (Rouviére) space were the most common recurrent sites after post-operative radiotherapy. On account of post-operative condition just after radical surgical procedure, postoperative radiotherapy for upper retropharyngeal (nasopharyngeal) space have not been performed in general, except for the cases with oropharyngeal infiltration. Six patients with post-operative radiotherapy showed retropharyngeal recurrence, 4 of them had multiple metastatic nodes in the excisional specimen that numbered six nodes or more. Patients who received more than 40Gy for nasopharyngeal space had no recurrence in retropharyngeal space. In the entire group, patients who were not irradiated for nasopharyngeal space with multiple metasatatic nodes numbered 28. In these patients, two in the surgical only group, and total 6 cases (6/28=21.4%) had retropharyngeal recurrence. In conclusion, irradiation for upper retropharyngeal (nasopharyngeal) space is indicated for patients not only with oropharyngeal infiltration, but also for these with multipe metastatic nodes.

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Background; Endobronchial irradation for lung cancer has primarily been used in cases of local progression or recurrence. Although its use for palliation of symptoms has been well evaluated, its role in treatment for cure is still unknown. We would like to report on the role of endobronchial irradiation as a curative therapy based on our clinical eXperience (long time survivors).
Methods; Forty-one patients treated with endobronchial irradiation using low dose rate 192lridium between February 1987 and December 1993 were made available for study. Of these, 17 were chest X-P negative cancer, 13 were post operative recurrent cancer, 7 were advanced cancer and 4 were tracheal cancer, respectively. The dose of endobronchial irradiation using an applicator with spacer was 5 to 7 Gy per session, administered either once or twice a week. EXternal irradiation was administered eXcept one case.
Results; Local recurrence was observed in two cases of chest X-P negative cancer, three cases of post operative cancer and five cases of advanced cancer. More than three years survivors were observed in 6 cases of chest X-P negative cancer, 5 cases of post operative cancer and one case of tracheal cancer. Complications due to endobronchial irradiation were seen in 2 cases, one case was pulmonary hemorrage and the other was shallow ulceration of the bronchus.
Coclusions: It was shown that chest X-P negative lung cancer and part of post operative recurrent cancer could be cured by endobronchial irradiation. This technique is considered to be useful for not only palliative therapy but curative therapy as well.

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47 patients (Male: Female 36: 11) with intrapelvic recurrent rectal cancer were prescribed radiation alone (17 patients), radiation and chemotherapy (18 patients) or radiation with hyperthermia (12 patients) from 1989 to 1995. There were no significant differences in patients' characteristics among these treatment groups. To discuss efficacies and disadvantages of these combined therapies, tumor response rate, pain control rate, duration of tumor control and pain control, and influence on patients' survival were evaluated.
Radiation was delivered to the whole pelvis (peri-internal iliac arterial and presacral regions). Mean total dose was 45.5Gy (1.5-2 Gy/fraction). Chemotherapy consisted 5-FU (p.o. daily) in 11 cases or CDDP and ADM (once during radiation therapy) in 7cases. Hyperthermia were added 3-6times (mean 4.5times) concomitantly to the radiation.
In all patients receiving more than 30Gy radiation, tumor response rate was 56.8%(PR 25/45patients). Tumor response rates were 35.3%, 43.7% and 41.7% in the radiation alone group, radiation and chemotherapy group and radiation with hyperthermia group respectively. Radiation combined chemotherapy was more effective for the tumor less than 5cm diameter than radiation alone (p<0.01). In cases receiving over 50Gy radiation, combined treatments were more effective than radiation alone (p<0.05). Pain relief was obtained in 75.9% of patients (22/29cases) and there were no difference between three treatment groups. Tumor control was significantoly prolonged in combined groups (p≤0.05). Median survival periods were 6, 10 and 7 months (N.S.) for radiation alone, radiation and chemotherapy, and radiation with hyperthermia respectively. In PR cases and for tumors under 5cm in diameter, there were no difference between three groups. In cases receiving over 50Gy radiation, survival period was prolonged in radiation with hyperthermia (p<0.05).
14 patients developed acute toxicity (Leucopenia) and late complication due to bowel obstruction. The incidence of bowel complication was 27.8% for radiation and chemotherapy and 33.3% for radio-hyperthermia, while 17.6%, significantly low percentage (p<0.05), for radiation alone. Bowel obstruction may occur positively correlated with postsurgical adhesions and infections at initial surgery (p<0.001).
These data suggest that combined radiation therapy with radiation, chemotherapy orh yperthermia was effective for local intrapelvic recurrence of rectal cancer especially in pain control. However, risk of bowel complication is increased by combined radiation therapy. This bowel complication is frequently observed in patients with post-surgical complications.

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We have developed a prototype system for a magnetic resonance (MR) simulation to accurately estimate radiation doses to the tumor and surrounding normal tissues during brachytherapy for cervical cancer. Six patients with cervical cancer underwent MR simulation prior to intracavitary high-dose-rate brachytherapy using Co-60 sources. Tandem and ovoid applicators filled with tap-water were placed in the uterine cavity and vaginal fornix, then MR imaging examinations were performed. Frontal and lateral images of maximum intensity projection (MIP) of applicators generated from a data set of half-Fourier single shot turbo spinecho (HASTE) images were chosen for processing by the treatment planning computer system. Then, isodose curves on the coronal or sagittal plane of the tandem section were superimposed on corresponding T2-weighted images derived from a turbo spin-echo technique. Doses to the tumor, the posterior wall of the urinary bladder, the anterior wall of the rectum, and the urethra were read from isodose curves superimposed on the T2-weighted sagittal image. Phantom experiments were done to evaluate geometrical errors. The possible distortion of the lattice image on the phantom was small. This system promises to be useful in customizing the dose distribution corresponding to the tumor and surrounding normal tissues.

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Mantle field irradiation for Hodgkin's disease has difficulties with respect to field localization, evaluation of delivered dose, etc. Sixty four radiotherapy facilities in Japan were surveyed using a postal questionnaire regarding eight physical factors in order to investigate the actual conditions. We discuss the finding compared with a Pattern of Care Study (PCS) in the United State and with some other literature. This analysis suggests that conditions in Japan are inferior to those in the US on almost all factors in radiation treatment for Hodgkin's disease.

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