Kenjiro Fukuhisa

High-dose-rate remote afterloading intracavitary radiation therapy for cancer of the uterine cervix. A 20-year experience

Retrospective analysis was performed on 1022 patients with squamous cell carcinoma of the uterine cervix who were treated with high‐dose‐rate remote afterloading intracavitary irradiation at the National Institute of Radiological Sciences, Angawa, Chiba‐shi, Japan, from 1968 to 1982 in comparison with low‐dose‐rate intracavitary radiation therapy. The patient population consisted of 147 patients with Stage I disease, 256 patients with Stage II disease, 515 patients with Stage III disease, and 104 patients with Stage IV disease. Absolute 5‐year survival rates for Stages Ib, IIa, IIb, IIIb, IVa, and IVb disease were 88.1%, 76.9%, 67.0%, 52.2%, 24.1%, and 13.3%, respectively. The rates of severe complication of Grades 3 and 4 were 4.1% for the rectosigmoid colon, 1.2% for the bladder, and 1.1% for the small intestine. In the case of Stage I to II disease, the optimal dose from intracavitary sources was suggested to be 2900 cGy ± 200 cGy at point A, with 4 to 5 fractions of 600 to 700 cGy delivered over 4 to 5 weeks. These results suggested that high‐dose‐rate intracavitary radiation therapy provided clinical results comparable to those of a low‐dose‐rate technique.

Second cancer after radiation therapy for cancer of the uterine cervix

Radiation‐induced cancers after radiation therapy for cancer of the uterine cervix were investigated on 11,855 patients including 5725 patients treated with radiation therapy alone, 1969 postoperative radiation therapy and 4161 surgery alone. The observed‐to‐expected ratios of the second primary cancer was 0.933 for the patients with radiation therapy alone and 1.074 for the patients with postoperative radiation therapy, respectively. No significant increase was observed in the risk of second primary cancers when all sites were combined. However, assessing on site by site basis, significant excess was noted for the rectum cancer, leukemia, and bladder cancer for the radiation therapy group but not for the surgery group. A significant excess of lung cancer was observed in both radiation therapy and surgery groups, which was attributed to some other causative factors. Radiation‐induced cancers were suggested to develop apparently in organs involved in the irradiated field.

Clinical experience of fast neutron therapy for carcinoma of the uterine cervix

Fast neutron therapy for locally advanced or radioresistant malignant tumors was started in November 1975 at the National Institute of Radiological Sciences (NIRS), Chiba, Japan. To evaluate the effectiveness of fast neutron therapy, mixed neutron-photon fractionated irradiation, on squamous cell carcinoma of the uterine cervix, 98 patients with Stage IIIb disease were examined to study the correlation between local control rate and histological types. The local control rate after neutron-mixed beam therapy was 73%, which decreased to 66% with photon irradiation. The five year survival rate was 49% for patients receiving neutron therapy and 49% for those receiving photon therapy. There was no statistical significance between neutron and photon therapy; we then attempted to analyze histological types to check for any gain using neutron therapy. This study was a nonrandomized trial. The preliminary results however, gave us useful information for the next of neutron therapy.

Analysis of bone scintigram data using a speech recognition reporting system.

A total of 649 bone scintigram reports were stored using a voice pattern recognition system in a general-purpose medium-sized computer ACOS-650, and bone scintigraphy carried out in this institute was examined by analysing these data. The results showed that the introduction of the system made it possible to analyse all the data quickly, whereas previously the amount of information that could be analysed was restricted because of the complexity of the data. The results also showed that the system would be useful for understanding the examinations carried out in the whole hospital as well as for analysing metastatic tumours and the numbers of patients receiving examinations. Furthermore, it would be helpful in the logical analysis of reports prepared by doctors.

Digital X-ray images of pneumoconiosis and their evaluation

The method of radiographic diagnosis of pneumoconiosis has been internationally standardized; namely, each film is evaluated according to the profusion, shape, and size of small opacities with reference to preselected standard X-ray films of typical pneumoconiosis [1, 2]. Recently, new diagnostic technologies such as computed tomography (CT) have been introduced, although they are still in the experimental stage [3–5]. In this chapter, we report the results of an objective study performed by many specialists on the applicability of the computed radiography (CR) system in the diagnosis of pneumoconiosis, a field which has a long history.

Fundamental Studies on Clinical Application of 13N-ammonia

放医研の医療用サイクロトロンを利用して, 13N-アンモニアを製造し, これの家兎の腸管内および静注の2つの投与経路での肝および心の13N-放射能動態の観察を行った。これに基づき, アンモニア代謝モデルを設定し, その解を適当な近似式に変換し, これにより腸管からのアンモニア吸収能, 肝内門脈分布, 実質細胞分布などで規定される諸パラメータ抽出の理論を展開した。