Toshio Kitagawa

Radiation therapy for advanced gastric cancer

A retrospective study of 75 patients with advanced inoperable gastric cancers, referred to the National Cancer Center Hospital between 1962 and 1982, was performed. According to the Borrmann classification based on X ray findings, Type 1 was found in 3 patients, Type 2 in 5, Type 3 in 40, and Type 4 in 15. Twelve patients could not be classified. The histological type was papillary adenocarcinoma in 7 patients, tubular adenocarcinoma in 23, mucinous carcinoma in 6, poorly differentiated adenocarcinoma in 14, signet ring cell carcinoma in 12 and others in 13. The site of remote metastasis in 19 patients was Virchows lymph node in 8 patients, Douglas pouch in 3, liver and lung in 2 each and others in 4. All patients were treated by a either telecobalt 60 unit or a linear accelerator using 6 Mv photon and the total dose to primary lesion was 4000 cGy in 5 weeks to 7000 cGy in 8-9 weeks. Complete response (CR) was achieved in 6 patients or 8.0%, partial response (PR) in 46 or 61.3%, and no change (NC) in 23 or 30.7%. The response rate based on the sum of CR and PR was about 70%. The 50% survival period in months was 26.5, 7.3, and 3.2, respectively for patients with CR, PR, and NC. For the response of advanced gastric cancer to chemotherapy in the National Cancer Center Hospital, the combined use of UFT and Mitomycin C gave the highest rate, 46%. As for as local response is concerned, the response rate to radiation was 70%, a better result than that of chemotherapy alone.

Indications of particle radiation therapy in the treatment of carcinoma of the esophagus

Studies were made to evaluate the role of radiations in the treatment of carcinoma of the esophagus to confirm indications for charged particles. Results of the studies showed that prognosis of the patients treated with radiations depend strongly on length of tumor as well as on invasion of tumor cells into the adventitia of the esophagus. It was concluded that patients suffering from carcinoma of the esophagus less than 8 cm length are indicated for particle radiations.

High-energy proton beam radiation therapy for gynecologic malignancies. Potential of proton beam as an alternative to brachytherapy.

Fifteen patients with advanced gynecologic malignancies were treated with high‐energy proton beam radiation therapy (RT) at the Particle Radiation Medical Science Center (PARMS), Tsukuba University, Japan, from 1983 to 1987. The potential of proton beam RT as an alternative to conventional brachytherapy was evaluated. Except for one local recurrence, 14 of 15 patients were locoregionally controlled for 15 to 57 months. Two‐year local control rate and 2‐year survival rate were 92.3% and 93.3%, respectively. Two cases of transient, radiation‐induced proctitis (neither of which required surgical treatment) were the only complications despite a target dose that exceeded 8000 cGy in most cases. The results suggest that sharply localized, high‐dose proton beam RT can produce an antitumor effect equivalent to that of conventional brachytherapy.

Normal brain damage after radiotherapy of brain tumours

A total of 106 patients were examined for adverse effects to the brain from 60Co or proton radiotherapy. Radiation induced change (RIC) developed within the irradiated field 40-60 months after doses of 800-1000 neuNSD or 70 TDF and in 10-20 months after doses of more than 1700 neuNSD or 100 TDF. The incidence of RIC increased significantly with increasing age. Furthermore pathological changes like oedema and infarction in the brain tissue may be an important factor for the development of RIC in the central nervous system (CNS).