Intensity modulated radiation therapy (IMRT) is the most advanced form of 3D-CRT. As with medical imaging, its development requires the professional activity of physicists and engineers. Recently IMRT, which uses beam intensity modulation, has been applicable to clinical radiation therapy. In practice, the IMRT plans are usually obtained using inverse planning, which derives a set of intensity-modulated beams by optimizing pre-defined objectives. IMRT has the potential to achieve a much higher degree of target conformity and/or normal tissue sparing than 3D-CRT. This new treatment technique might be very useful for clinical radiation therapy, especially for carcinoma of the head and neck, the breast and the prostate. It presented that sparing the parotid glands translates into objective and subjective improvements of xerostomia in head and neck cancer patients and the reduction of grade 2-3 late radiation morbidity of the rectum or bladder in prostate cancer patients using IMRT. But we see that no definitive studies have conclusively demonstrated the impact of IMRT on improved tumor control and decreased long-term morbidity, nor have any studies demonstrated the superiority of one particular IMRT technique. Brain, pancreas, stomach and cervix carcinoma might also be an indication for this new treatment.
Although the instrumentation and methods used for IMRT QA procedures and testing are not yet well established, we have to check the QA procedures at least for machine, patient and planning soft wear. In addition, many fundamental questions regarding IMRT are still unanswered.
It is an urgent problem in our radiation oncology community to establish the QA guidelines for IMRT and to have enough supply of manpower of medical physicists to facilities, which use IMRT.

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Radiotherapy for cervical cancer has become increasingly sophisticated with many clinical results. However, most radiation therapy techniques have been based on single institutional experiences. These centers of excellence have a large experience with radiation for cervical cancer and continue to evaluate their techniques and outcome. The Patterns of Care Study (PCS) in the United States conducted two national surveys of patients treated in 1973 and 1978 for squamous cell cancer of the uterine cervix. In this study, the only treatment factor associated with improved pelvic control in multivariate analysis was the use of intracavitary irradiation. A dose response for infield pelvic control was demonstrated only in Stage III cervical cancer with the highest rate of pelvic control with paracentral (PCS point A) dose greater than 8, 500 cGy. In Japan, the influence of age on the process of radiotherapy for cervical cancer was analyzed with PCS. Lower pelvic radiation doses were used for the elder patients with advanced stage disease. Brachytherapy was used less commonly in the elderly group than in younger one. As a result, preliminary survival rates for the elderly were similar to those for the younger group. The representative guideline for treating cervical cancer that is evaluated as EBM is proposed by NCI. However, this guideline shows only the strategy and do not show the practical treatment methods. It must be kept in mind that there are several pitfalls to evaluate the treatment outcome for cervical cancer as EBM.

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Introduction: Recently, the number of patients requiring radiation treatment has been increasing. Rapid operation for taking linacgraphy of the field and checking is needed. The contrast of linacgraphy with conventional films is so low that the improvement of contrast is needed. To introduce FCR system into the Radiotherapy subdivision is one way of improving this point. Purpose: The purpose of this paper is to evaluate the efficiency and quality when introducing of FCR into the Radiotherapy subdivision. Methods:
1) The best photography parameter for linacgraphy of the irradiation field and the whole field in the differences of output was evaluated.
2) An influence over the picture quality when changing the parameter GA value (the turn quantity) of FCR with all kinds, the GS value (the gradation shift value), the RE value (the frequency or more furniture) was evaluated. Result:
1) The best parameters for linacgraphy were 3.0 MU and 1.0 MU in each of the whole field and irradiation fi eld. When the size of body was large, t0.5 MU must be added to each parameter.
2) The best parameter condition of FCR was in the chest; GA: 3.0, GS:-0.55, RE: 3.0, in abdomen; GA: 3.0, GS:-0.55, RE: 5.0 and in the pelvis and vertebra; GA: 4.0, GS:-0.55, RE: 5.0. Conclusion: Good picture quality can be obtained by changing the old system to the updated FCR system in the Radiotherapy subdivision, and costs will be saved.

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Purpose: With scanning electron microscopy, we investigated the effectiveness of inhibition by endovascular irradiation (Ir-192 high dose rate) of intimal hyperplasia after angioplasty. We also examined changes in the irradiated arterial vessel wall after balloon injury and the mechanism of the inhibition of intimal hyperplasia.
Materials and Methods: Japanese white rabbits (male, 3.0-3.5 kg) were used. Under anesthesia, a percutanous transluminal angioplasty balloon catheter was inserted into the iliac arteries and inflated to 6 atm for 1 minute 3 times at 1-minute intervals. One artery was irradiated (12 Gy) with an iridium-192 high-dose rate endovascular irradiation device (the reference point was set at 2 mm to center; dose rate 18-48 Gy/min). From 2 days to 12 weeks after the procedure, fixation was performed at a perfusion pressure of 120 to 150 cm H₂O, and the arteries were systematically examined. Endothelial cells after balloon injury with or without irradiation were examined with light microscopy or scanning electron microscopy.
Results: Endovascular irradiation inhibited intimal hyperplasia for at least 12 weeks. Irradiated arteries were not constricted, so we assumed that this phenomenon was caused by inhibition of negative remodeling. From 1 to 2 weeks after the procedure, we recognized mild intimal hyperplasia at nonirradiated arteries, but no hyperplasia recognized at irradiated arteries. This hyperplasia was mainly constituted by endothelial cells, and this change happened at least 2 days with scanning electron scopy. At the injury site, platelet aggregation, thrombus, and endotherial cells were observed. After irradiation, endothelial cells and nuclei were injured. Hypertrophic nuclei, the deformity of cell alignment, and stratified endothelial cells were recognized. It means that irradiation may affect the metabolism of the endothelial cells against normal formation with light microscopy.

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Purpose: To investigate the incidence, clinical and radiological findings of insufficiency fractures (IF) of the female pelvis following radiation therapy.
Patients and methods: We retrospectively reviewed the radiation oncology records of 108 patients with gynecologic malignancies who underwent external beam radiation therapy of the whole pelvis. All patients underwent conventional radiography and computed tomography (CT) scan every 6 months in follow-up after radiation therapy and magnetic resonance imaging (MRI) and radionuclide bone scan were added when the patients complained of pelvic pain.
Results: Thirteen of 108 patients (12%) developed IF in the irradiated field with a median interval of 6 months (range 3-51) from the completion of external beam radiation therapy. All patients who developed IF were postmenopausal women. Age of the patients who developed IF was significantly higher than that of the other patients. The parts of IF were sacloiliac joints, pubis, sacral body and 5th lumbar vertebra and six of 14 patients had multiple lesions. Treatment with rest and nonsteroidal anti-inflammatory drugs lead to symptomatic relief in all patients, although symptoms lasted from 3 to 20 months.
Conclusions: Radiation-induced pelvic IF following radiation therapy for gynecologic malignancies were frequently observed in the post-menopausal patients within 1 year after external beam radiation therapy. Symmetrical fractures of the bilateral sacroiliac joint and pubis were the characteristic pattern of pelvic IF. All patients healed with conservative treatment, and nobody became non-ambulant.

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Introduction: Evaluation of QOL in cancer patients is an important theme. However, we do not have an established method to assess QOL in cancer patients during radiotherapy in Japan. We evaluated both the changes of QOL and the factors affecting QOL in radiotherapy patients.
Materials and Methods: Three hundred and fifty-five cancer patients, who filled in a questionnaire at the beginning, middle, and end of radiotherapy between 1998 and 2001, were studied. Weused“The QOL Questionnaire for Cancer Patients Treated with Anticancer Drugs (QOL-ACD)” devisedby Kurihara et al, the Ministry of Health and Welfare. The QOL Questionnaire had five categories: physical activity, physical condition, mental state, social interaction, and face scale. The total score, sum of the score of five categories, were established synthetically (maximum score is 110).
Results: The mean of total QOL scores were 75.8, 77.6, and 78.2 at the beginning, middle, and end of radiotherapy respectively. Patients with symptoms related to cancer had apparent improvement of QOL score. Patients receiving chemotherapy had a decreased QOL score at the end of radiotherapy. The score of physical condition was reduced improvement.
Conclusions: It was suggested that radiotherapy could be performed without losing QOL of cancer patients, including older patients. However, patients receiving chemotherapy and those with head and neck cancer may lose their QOL, therfore, we should treat such patients carefully.

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Purpose: Radiation therapy is an established method for treatment of early glottic cancers. Since the larynx is a thin wedge-shaped structure in the anterior neck adjacent to the airway, the absorbed doses to the lesion may be diminished because of build-up and build-down. The dose has been measured with conventional measuring systems such as thermoluminescent dosimetry (TLD). In this study, we employed Gafchromic MD-55-2 film (Nuclear Associates, Inc) as a dosimeter, for it can be set on the area of interest and with a measurability of a dose range of 3 to 100 Gy, and this radiometer material is similar in soft tissue of the human body. The dose distributions to the larynx were investigated with this film using a neck phantom under radiation beam energies of 4, 6 and 10 MV X-rays.
Material and Method: The neck phantom was irradiated using 4, 6 and 10 MV X-rays, each with right and left lateral parallel-opposed fields, total radiation dose of 20 Gy, field size of 6 cm X 6 cm and 15 degrees wedge filter.
Result: As a result, we observed secondary build-up and build-down curves in tissue in the vicinity of air cavities, especially at 10 MV X-rays. In the anterior commissure·center of glottic region, the absorbed doses decreasing rates of absorbed dose to 20 Gy with 4, 6, and 10 MV X-rays were 6.15%·7.35%, 8.90%·9.45% and 15.6%·12.7% respectively.
Conclusion: These findings suggest that patients with early glottic cancer with anterior commissure invasion may receive more effective treatment with 4 MV X-rays rather than with 6 MV or 10 MV X-rays.

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Radical cystectomy has been a standard treatment for invasive urinary bladder cancer, however preservation therapy is being considered in many facilities as a clinical examination. After transurethral resection of the bladder (TUR-Bt), three-time transarterial infusion (TAI) of CDDP 45mg/m², MTX 30mg/m² and local five-port external beam radiation therapy (EBRT) of 60Gy/30fx/6 wks were delivered concurrently. Because such reports of organ sparing treatment using TAI are few, a mono-arm prospective study was designed to evaluate the rate of CR (RECIST standard) and the incidence of acute toxicity (NCI standard) compared with previous reports in which intravenous chemotherapy was used in a tri-modality treatment protocol.
Twenty-three patients with T_2-4N₀M₀ or High risk T₁N₀M₀ were registered (T₁; 7, T₂; 7, T₃; 8, T₄; 1). They were all in good PS (0-1). CR rate after intravesical therapy with bacilli Calmette-Guerin was eighty-seven percent (CI 66-97%). There was a significant difference (p=0.03) between this value and that (CR rate=62%, n=299) calculated from two reports in which transvenous chemotherapy was used as one of the treatment modalities.
Grade three white blood cell decrease was seen in twenty-six percent of patients. This was significantly higher than the value estimated from reports using cisplatin only as the single chemotherapy agent. An acute reaction of the urinary bladder and rectum was negligible.
After fifteen-month follow-up, four patients relapsed and two showed metastatic lesions. According to the protocol, three of the former four had already received cystectomy, but one had undergone an intra-vesicle BCG injection because it showed non-invasive papillary histology, and reached CR again. M-VAC chemotherapy was performed for the latter two who got metastases with minimal effects.
It was concluded that this conservative tri-modal treatment with TAI is safe and effective as far as an early reaction is concerned compared to tri-modality treatment with intravenous chemotherapy.

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Purpose: We employ a clinical target volume (CTV)-based dose prescription for high-dose-rate (HDR) interstitial brachytherapy. However, it is not easy to define CTV and organs at risk (OAR) from X-ray film or CT scanning. To solve this problem, we have utilized metal markers since October 1999. Moreover, metal markers can help modify dose prescription. By regulating the doses to the metal markers, refining the dose prescription can easily be achieved. In this research, we investigated the usefulness of the metal markers. Methods and Materials: Between October 1999 and May 2001, 51 patients were implanted with metal markers at Osaka Medical Center for Cancer and Cardiovascular Diseases (OMCC), Osaka National Hospital (ONH) and Sanda City Hospital (SCH). Forty-nine patients (head and neck: 32; pelvis: 11; soft tissue: 3; breast: 3) using metal markers were analyzed. During operation, we implanted 179 metal markers (49 patients) to CTV and 151 markers (26 patients) to OAR. At treatment planning, CTV was reconstructed judging from the metal markers, applicator position and operation records. Generally, we prescribed the tumoricidal dose to an isodose surface that covers CTV. We also planned to limit the doses to OAR lower than certain levels. The maximum normal tissue doses were decided 80%, 150%, 100%, 50% and 200% of the prescribed doses for the rectum, the urethra, the mandible, the skin and the large vessel, respectively. The doses to the metal markers using CTV-based dose prescription were generated. These were compared with the doses theoretically calculated with the Paris system. Treatment results were also investigated.
Results: The doses to the 158 metal markers (42 patients) for CTV were higher than “tumoricidal dose”. In 7 patients, as a result of compromised dose prescription, 9 markers were lower than the tumoricidal dose. The other 12 markers (7%) were excluded from dose evaluation because they were judged as miss-implanted. The doses to the 142 metal markers (24 patients) for OAR were lower than the maximum normal tissue doses. The doses of 2 markers (1 patient) for OAR (the urethra) were higher than the maximum normal tissue dose. Seven markers for OAR (the mandible) were not visualized because of metal crowns. If the Paris system (reference dose is prescribed to an isodose surface of 85% of the basal dose) had been used, 16 patients had been “underdosed” and 4 patients (the rectum+the urethra: 2; the urethra: 1; the large vessel: I)“overdosed”. Dose non-uniformity ratio (DNR) and maximum diameter of hyperdose sleeve were 0.31±0.08 and 4-49 mm (median: 7 mm) in CTV-based dose prescription. A statistically significant difference was seen between CTV-based dose prescription and Paris system 0.28±0.08 and 3-99 mm (median: 6 mm)(p<0.002, 0.0002). Two of 42 patients treated with higher than the tumoricidal dose had local recurrence, while 4 of 7 underdosed patients had local recurrence. A significant difference was found between them (p<0.0001).
Conclusions: Metal markers were useful to prescribe the tumoricidal dose to CTV and to regulate the doses for OAR. Local control rate of the patients treated with higher than the tumoricidal dose was significantly better. Miss-implantation of metal markers was a problem that should be resolved.

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