Hyogo Ion Beam Medical Center is a new ion beam treatment facility which was opened in April 2001. Ion beam treatment at this center comprises an irradiation system, a treatment planning system and a treatment verification system. The irradiation system consists of huge machines that might seem to play a major role in ion beam therapy, however, two other systems also play absolutely important role.
Holistic and highly precise functions of these three systems are essential and cooperative work among radiation oncologists, medical physicists, radiological technologists and nurses is more important than anything else in performing this highly sophisticated treatment.

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In Japan, where the mortality rate of prostate cancer is lower than in Western countries, there is little evidence of radiation therapy for prostate cancer. Therefore, we have to refer to the evidence of radiation therapy from Western countries, but we should pay attention to the differences of cultural, racial, or social background between Japan and Western countries. The Patterns of Care Study (PCS) was conducted in Japan and extramural audits were performed for 50 randomly selected institutions. Detailed information of 311 prostate cancer patients without distant metastases and other cancers, who were treated with radiation therapy in 1996-1998, was collected. In this article, the results of PCS for primary prostate cancer were shown, with a review of literature for the appropriate choice of radiation therapy. This study was supported by the Grantin-Aid for Cancer Research from Ministry of Health, Labor and Welfare (10-17).

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Evidence-based medicine (EBM) is not “cookbook” medicine because it requires a bottom up approach that integrates the best research evidence with clinical expertise and patient values. We should keep our patients informed as we work our way through making clinical decisions. The practice of EBM is essential for obtaining informed consent. It comprises four steps. Step I: asking answerable clinical questions. Step 2: how to find current best evidence. Step 3: critical appraisal. Step 4: review the applicability of the evidence to our patients. Every step is illustrated using two clinical scenarios. One is for the effectiveness of boost irradiation for negative margin and the other for breast conservation therapy during pregnancy. The PICO model is convenient in step 1. Evidence-based electronic textbook, practice guidelines or secondary resources are useful. We should get used to searching for best evidence through MEDLINE. The CASP program helps making sense of the evidence. The best evidence must be integrated with individual clinical expertise in deciding how it matches patient values, and thus whether it should be applied. By practicing EBM we hope to be caring radiation oncologists with good oncological knowledge when treating cancer patients.

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Purpose: We retrospectively analyzed patients with advanced esophageal cancer complicated by mediastinitis or esophagotracheal fistula who had undergone radiation therapy (RT_x). The purpose of this study was to evaluate RT_x and the RT_x procedure in cases of advanced esophageal cancer involving complications.
Materials and Methods: Eleven patients with esophageal cancer complicated by mediastinitis and seven patients with esophageal cancer complicated by esophagotracheal fistula who had undergone radiation therapy atYamagata University Hospital between 1987 and 2001 were analyzed. The cases were classified as Group I or Group II. Group I consisted of 5 cases of mediastinitis and 4 cases of esophagotracheal fistula in which the complication appeared before RT_x. Group II consisted of 6 cases of mediastinitis and 3 cases of esophagotracheal fistula in which the complication appeared during RT_x. Each group was also classified as Group A and Group B according to the RT_x procedure. When complications appeared, patients in Group A-6 with mediastinitis and 4 with esophagotracheal fistula-took a break from RT_x, resuming the treatment with 2 Gy after clinical signs improved. Patients in Group B-5 with mediastinitis and 3 with esophagotracheal fistula-continued RT_x with 1.8 Gy even if complications appeared. We analyzed the effectiveness of RT_x, the RT_x procedure, and the results of RT_x for cases of advanced esophageal cancer with mediastinitis oresophagotracheal fistula.
Results: The median survival times for patients in Group I and Group II were 5.0 months and 4.0 months, respectively. The median survival times for patients in Group A and Group B were 4.9 months and 3.8 months, respectively. There were no differences in survival rate, tumor response or treatment results for the different RT_x procedures or the time at which the complications appeared. Patients who had RT_x with 1.8 Gy tended to have a shorter RT_x period and hospitalization than patients who had 2 Gy.
Conclusion: It was possible to give RT_x to patients with esophageal cancer involving mediastinitis or esophagotracheal fistula. RT_x with 1.8 Gy per fraction made it possible for patients with advanced esophageal cancer involving mediastinitis or esophagotracheal fistula to eat food or be discharged earlier. RT_x with 1.8 Gy per fraction contributed to the quality of life of patients who had a poor prognosis. The results suggest that RT_x for advanced esophageal cancer involving such complications as mediastinitis or esophagotracheal fistula was effective. The optimal dose was 1.8 Gy per fraction.

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Purpose: To retrospectively investigate the efficacy of multidisciplinary therapy (concomitant radiotherapy and intra-arterial infusion of 5-fluorouracil (5-FU) followed by maxillectomy) in the treatment of squamous cell carcinoma of the maxillary sinus.
Materials and Methods: We reviewed 71 patient records with locally advanced but resectable carcinoma of the maxillary sinus treated by means of multidisciplinary therapy between 1978 through 1997. The clinical T factor for these patients, according to the UICC definitions (1997), was 12 for T2, 46 for T3, and 13 for T4. Twelve patients were diagnosed as node-positive at initial presentation. Intra-arterial 5-FU was delivered via a superficial temporal artery in accordance with radiotherapy, and the cumulative 5-FU dose ranged from 2, 900 mg to 5, 250 mg (median 5, 000 mg). The total radiotherapy dose ranged from 29 Gy to 48 Gy (median 48 Gy) with conventional fractionation. Patients underwent radical maxillectomy thereafter.
Results: The 5-year overall survival rate and disease-specific survival rate of all the patients were 58% and 68%, respectively. There was no significant correlation of clinical T factor or N factor with disease-specific survival on univariate and multivariate analysis. The overall treatment-related mortality rate was 3.7%. Radiation cataract later developed in all evaluable patients whose lenses were within the treatment volume.
Conclusions: About a half of the operable T4 patients survived over 5 years by means of the above-mentioned multidisciplinary therapy. This multidisciplinary therapy should be compared to treatment with a combination of surgery and postoperative chemoradiotherapy.

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The purpose of this study was to develop a novel re-locatable head frame system consisting of a dental cast and hydraulic arms as an immobilization device for fractionated stereotactic radiotherapy and to evaluate the repositioning accuracy by measurement of landmark coordinates in repeated computed tomography (CT) examinations. The acrylic dental casts were customized for each patient. First the dental cast was attached to the upper jaw of the patient, then the dental cast was connected to a Leksell stereotactic frame, which was finally secured by two hydraulic arms. Since this system is compatible with the Leksell frame, stereotactic indicators could be used to obtain coordinates of anatomical landmarks of the head.
Seven patients treated by fractionated stereotactic radiotherapy underwent repeated quality-assurance CTs during their treatment courses. We evaluated the coordinates of the short process of incus and the top of crista galli as reference points for evaluation of variation in a total of 26 repeat CT data sets, and then x, y, and z fluctuations relative to their positions in the treatment-planning CTs. The distances among the reference points of both processes of incus and the top of crista galli were calculated to evaluate the feasibility of the method. The distances were less than 0.5 mm on averages and less than 1 mm in the standard deviations. The respective fluctuations in the x, y and z directions were less than 1 mm in mean values and less than 2 mm in standard deviations. The fluctuations in distance were less than 2 mm on average and in standard deviations. The fluctuation of the center of three reference points was 0.7 mm on average and the rotation of the cranium was 1.0 degree in average. We concluded that our evaluation method is feasible and the reproducibility of the fi xation system is acceptable for its routine use in stereotactic radiotherapy.

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Objective: To evaluate the influence of the time interval between surgery and start of postoperative radiotherapy on prognosis in patients with a resetcable NSCLC.
Methods: Between April 1991 and February 1999, 67 patients with pathologically proven non-small cell lung cancer underwent postoperative radiotherapy. There were 45 men and 22 women (median age 65 years). The histology was squamous cell carcinoma in 27 patients, adenocarcinoma in 36, others in 4. The median interval between operation and irradiation was 34 days. The irradiation fields included the surgical margin, mediastinal and ipsilateral hilar lymph nodes. In cases with negative surgical margins, the total dose was 50 Gy in 22 or 25 fractions. A boost irradiation was added to positive surgical margins with a dose of 10-20 Gy.The median follow-up period was 53 months.
Results: For all 67 patients, 5-year overall survival rate was 39.7% and 5-year cause-specific survival rate 46.6%. There were no statistically significant differences in overall survivals, cause-specific survivals, and local recurrence free survivals between the patients with a short interval (≤34 days) and a long interval (≥35 days).
Conclusions: Survival of patients with a short interval between surgery and start of radiotherapy was not significantly different from the patients with a long interval.

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We retrospectively analyzed cervical cancer patients with narrow vagina treated by high-dose-rate (HDR) brachytherapy followed by external beam irradiation. Fifty patients were treated with radical radiotherapy between 1992 and 1999 at the National Tokyo Medical Center. All patients received 30 Gy of external whole pelvic irradiation and 20 Gy of pelvic irradiation with a central shield. After 30 Gy of whole pelvic irradiation, 24 Gy of fractionated brachytherapy was applied with a tandem and ovoids, non-rigid type developed in the Cancer Institute, according to the Manchester method. Nineteen patients with a narrow vagina of less than 40 mm in width were compared with 31 other patients (control group). The 5-year cumulative survival rates were 56% in the patients with a narrow vagina and 53% in the control group (P=0.6008). The control rate in the pelvis was not significantly different between the two groups.The cumulative rate of rectal complications of the patients with a narrow vagina was more frequent than the control group (58% vs 29%)(P=0.0924). Severe rectal bleeding was also more frequent in the patients with a narrow vagina. The estimated maximal dose of the rectal wall was significantly higher in patients with a narrow vagina. This result suggests that a lower brachytherapy dose is necessary for patients with narrow vagina considering the rectal sequelae in the case of using our methods.

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