Cloning of all human genome has beem completed in 2000 with the beginning of 21st century close at hand, and the full-scale post-genome era has come at last. The department of radiology that should take an important role in medical medicine was one of the few departments that had not taken part in the human genome projects that can be the fundamental plan of life. Of course, there are some human genomes sequenced by researchers of radiobiology or of basic medicine of radiation, however, they are exceptional. As the contrary to the proverb, “You will win every battle, if you know your enemy and yourself, ” radiologists in the past have entrusted it to physicians in other departments, and they have had little interest in the outcomes of such researches. We have completed cloning of four novel human genomes that can be related with cancer or radiosensitivity, and reported them in articles. We would like to consider the new idea, clinical activities in the department of radiology should play an active part in the era of postgenome. Here we are not concerned with the future prospective of radiology in departments related with IT, such as telemedicine, as we are not in a position to mention it.

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Interstitial brachytherapy with ¹²⁵I seeds for treatment of prostate cancer is being carried out successfully in Europe and U. S. A. However, its widespread use in Japan has been limited by regulations governing the exposure of individuals. Basic radiation protection data are required to promote the use of ¹²⁵I seed sources. In preparation for implementing this new modality, we carried out a series of measurements to determine the 1 cm dose equivalent in a caregiver located 1 m from the implanted patient. These measurements were compared with published recommendations of acceptable doses, and may be used to develop guidelines for discharge of the patient. The 1 cm dose equivalent was measured 1 m from the source under clinicallyrelevant conditions by placing 50 125I seeds (437.5 MBq) into the portion of a humanoid phantom that corresponds to the prostate. The 1cm dose equivalent was 0.0014μ Sv·m²·MBq^-1·h^-1 1m from the surface of the phantom. The calculated dose to a caregiver based on this figure is well below the 5 mSv value recommended by the IAEA as a constraint dose for the caregiver. These measurements and calculations suggest that ¹²⁵I seed implants of outpatients should be permissible.

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Objective: Our policy for radiation therapy to squamous cell carcinoma of the uterine cervix has not changed since 1970. We have already reported the treatment results, and thought that these outcome was as good as those from other institutions. Recently, several randomized controlled studies showed significant improvement of the treatment results with radiation therapy combined with concomitant chemotherapy. We therefore analyzed treatment results in order to re-evaluate the treatment policy.
Materials and methods: A retrospective analysis was carried out from the records of 379 patients with cervical squamous cell carcinoma who had been given radiation therapy between 1970 and 1994. A combination of external pelvic irradiation and three sessions of low dose rate intracavitary brachytherapy was performed. Prophylactic irradiation to the abdominal paraaortic lymphnodes was not performed. Adjuvant chemotherapy was not administrated as a principle.
Results: The 5-year overall survival rates were 80% in stage I, 73% in stage II, 52% in stage III, 34% in stage IVa, and 14% in stage IVb. The cause-specific survival rates were 98% in stage I, 84% in stage II, 71% in stage III, 53% in stage IVa, and 14% in stage IVb. The 5-year cumulative intra-pelvic recurrence rates were 8% in stage II, 15% in stage III, and 25% in stage IVa, respectively. The 5-year cumulative extra-pelvic recurrence alone rates were 7% in stage II, 21% in stage III, and 18% in stage IVa, respectively. The main cause of intra-pelvic recurrence was insufficient delivery of dose by intracavitary brachytherapy. The complication rates of Grades 1-2, 3, and 4 were 26.7%, 4.0%, and 5.5% respectively.
Conclusion: Radiation therapy with external pelvic irradiation combined with three sessions of low dose rate intracavitary brachytherapy was effective and safe for patients with squamous cell carcinoma of the uterine cervix. We consider that it is not necessary to change our policy at present. It is conceivable that radiation therapy with concomitant chemotherapy with CDDP may be performed only in those cases for whom an insufficient delivery of dose by intracavitary brachytherapy is suspected.

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Conformal radiation therapy, which is widely utilized in Japan as a standard, highly precise technique has limited adavantage in dose confinement because of its coplanar beam entry. An improved form of conformal therapy is delivered by a linac mounted on a C-arm rotatable gantry. The linac head was designed to move along the C-arm with a maximum angle of 60 degrees. Simultaneous rotation of the gantry creates a Dynamic Conical irradiation technique. Dynamic Conical Conformal Therapy (Dyconic Therapy) was developed by combining the technique with continuous MLC motion based on beam's eye views of the target volume. Dose distributions were measured in a phantom using film densitometry and compared with conventional conformal radiation therapy. The measurements showed that the dose distribution conformed to the target shape identified by CT. In addition, the dose distribution for a cancer patient was evaluated through the use of DVHs generated by a treatment planning system. These measurements showed that the dose distribution along the patient's long axis conformed to the shape of the target volume. DVH analysis, however, did not indicate superiority of the present technique over the conventional technique. Angulation of the C-arm gantry allowed the primary beam to strike a larger area of the therapy room. This necessitated adding shielding to the walls and ceiling of the treatment room. It was confirmed that the leakage radiation was reduced to a negligible level by adding an iron plate 20 cm thick to several places on the side walls, by adding an iron plate 9 cm thick to several places on the ceiling, and by increasing the thickness of the concrete ceiling from 70 to 140 cm. The possible usefulness of Dyconic Therapy was confirmed.

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To evaluate the effects of radiation on various types of EMS (expandable metallic stent) that differ in shape and the quality of the material, we performed external irradiation and intraluminal irradiation using 5 types (Spiral Z stent: SZ, Wallstent: Wall, NT stent: NT, ZA stent: ZA, Accuflex: Acc.) of EMS for the biliary tract, and measured back scatter on the EMS interface and absorption due to shielding using TL (thermoluminescent) sheets. TL sheets can be wound around the external side of the EMS in water, allowing phantom experiments close to the in vivo state for the measurement of dose perturbation of radiation near the EMS. Images of the relative dose in a small area near the EMS were obtained using a spatial read-out system using a cooled CCD camera. In external irradiation, an 8.2 ±0.53% increase in back scatter was observed in SZ with a wire diameter of 260μm and 7.9±1.2% and 4.5±0.62% decreases in absorption due to shielding in SZ and Wall, respectively. In intraluminal irradiation, a 7.7±0.85% decrease in absorption was observed in SZ alone. Therefore, in both external and intraluminal irradiation on various types of EMS that differ in shape and the quality of the material, the dose perturbation near the EMS is 8.2% or less, which presents no clinical problem.

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We have been tried to construct the database about treatment of a radiation in whole Japan since the old days. Through looking back the progress of our works, we report the current activities of the JASTRO (Japanese Society for Therapeutic Radiation Oncology) Data-Base Committee. A survey on radiation treatment facilities structure in Japan, and a construction of ROGAD (Radiation oncology greater area database) are two main activities of the JASTRO Database committee. We give outline of these activities and review limitations and problems what we have experienced through our activities and in conclusion we refer to our future goal. The vote of our survey on radiation treatment facilities structure in Japan is attached at the end of this article.

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Radiation Oncology Greater Area Database (ROGAD) has been developed in the Japanese Society for Therapeutic Radiology and Oncology From 1992 to 1998, 8, 950 records of radiotherapy were accumulated m the ROGAD from 231 institutions in Japan To evaluate the clinical usefulness of the ROGAD, we examined the data sets of 653 patients limited to esophageal cancer.
(1) There were high rates of emptied registration in the diagnostic fields (Stage 23 2%, T factor 19 3%, N factor 19.0%, M factor 17.3%, c-, p-, r-symbol of TNM classification 17.3%) and in the fields of therapeutic results (acute radiation morbidity. 17 9%, survival status 17.3%, follow-up date: 16 1%, response. 13.2%, performance status at termination 12 4%).(2) As the treatment methods, radiation alone was employed most frequently in 47 9%, chemoradiotherapy in 24.9%, combined surgery with radiation in 17 9%, in that order (3) A substantial increase was demonstrated between 1992 and 1998 in the proportion of esophageal cancer treated with chemoradiotherapy (13.5% in 1992-95 vs. 28 5% in 1996-98), while a considerable decrease in the percentage of cases receiving surgery and radiation (22.4% in 1992-95 vs. 16.4% in 1996-98).
The technical aspect of the ROGAD is almost completed, however, more efforts are necessary to improve the data accuracy.

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Radiotherapy clinical records of 8, 950 cases were collected from 251 hospitals in the period from 1992 to 1998 by the activity of Radiation Oncology Greater Area Database ROGAD under the Japanese Society for Therapeutic Radiology and Oncology JASTRO, and their data were analyzed. Outlines of analysis are presented in this paper and other 5 papers in series.
Also follow-up data of 814 cases by the 4th follow-up survey study carried out in 1998 were retrieved and examined.
Case distribution survey according to ICD-O code for primary tumor region were worked out. Chronological change of case distribution during these seven years were examined and briefly stated in this paper. Case analyses in terms of 5 portions of topographical region were also done, and 5 papers together with this paper describe the results of the analyses.
Data analysis comparison between ROGAD and the regular census revealed that the resulted analyses of collected clinical data by ROGAD from 1992 to 1998 indicated the real world of radiation therapy situation in Japan. One of the reason to state this is that ROGAD covers 34.7% of number of facilities and 36.1% of number of cases treated in Japan. The another reason is that we could reduce the rate of mis-registration and items of blanked registration by means of improvement of registration software with logical check.
We made sure from our effort of this ROGAD activity for these 7 years experiences that continuation of the run of this database ROGAD would bring us much more accurate information on the radiation oncology situation in Japan.

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