[Injury to ascending aorta by cross-clamp--histologic evaluation].

To evaluate the injury to ascending aorta by cross-clamp, the trauma to the vessel wall was examined microscopically and the occlusive intensity of the vascular clamp was measured. Six patients were underwent total replacement of the ascending aorta and the aortic arch for aortic dissection. The ascending aorta and the aortic arch were resected during operation, the clamped regions of the ascending aorta were cut into the four pieces (the distal site, two part of the medial site, the proximal site applied by the vascular clamp) after operation. The four pieces of the ascending aorta were examined microscopically. The occlusive intensity of the vascular clamp were measured at the distal site, the medial site, and the proximal site by the load-measuring scale. The trauma to the vessel wall were classified to three degrees (grade 1 to grade 3). Grade 1 showed the minimal changes--narrowing of interstices between collagen fibers and muscle fibers in the media. Grade 2 showed the moderate changes--decrease of collagen fibers, atrophy and disruption of smooth muscle and elastic fiber in the media. Grade 3 showed the severe changes--disruption of the intima and defluvium of endothelial cells. The occlusive intensity of the vascular clamp were 1.0 kg at the distal site, 1.9 kg at the medial site and 3.6 kg at the proximal site, respectively. In the microscopic examinations, grade 1 changes were most frequent at the distal site, grade 1 and grade 2 changes were observed equally at the medial site, grade 3 change was observed only at the proximal site. The degree of the trauma to the vessel wall becomes severer in proportion to increase of the occlusive intensity of the vascular clamp.

[Double chambered right ventricle in a 59-year-old man].

Surgical experience of double chambered right ventricle in a 59-year-old man was reported. The patient who had been pointed out for his systolic manner without any symptoms was admitted to our hospital because of heart failure. Cardiac catheterization revealed an about 80-mmHg peak-to-peak gradient in the right ventricle cavity with normal pulmonary pressure. Cineangiogram demonstrated double chambered right ventricle with perimembranous ventricular septal defect. Surgical repair with right ventriculotomy was performed in order to release pressure gradient and his symptoms. Right ventricular function after operation was not distorted. It is important to choose the surgical approach (right ventriculotomy or transatrial approach) for release the pressure gradient completely.

[A case report of transaortic mitral valve replacement in Marfan's syndrome].

One-stage operation was successfully performed in 30-year-old male with annulo aortic ectasia and mitral valve regurgitation secondary to Marfan's syndrome. The replacement of the mitral valve was performed through aortic root. The transaortic mitral valve replacement employed here should prove useful for similar cases requiring reconstruction of aortic root and replacement of mitral valve simultaneously in Malfan's syndrome.

A comparison of the structure of radiation oncology in the United States and Japan.

PURPOSE: The United States and Japan have very different backgrounds in their medical care systems. In the field of radiation oncology, national surveys on structure have been conducted for both countries and compared to illustrate any similarities and differences present from 1989-1990. METHODS AND MATERIALS: The Patterns of Care Study Facility Survey conducted in 1989 in the United States and the National Survey of Structure in Japan in 1990 were compared to evaluate the equipment pattern, staffing pattern, compliance rate with the "blue book" (3) guideline, and the geographic distribution of institutions. RESULTS: In the United States, a total of 598,184 (49% of the total of newly diagnosed) patients were treated with radiation therapy. In Japan, 62,829 (approximately 15% of the total of newly diagnosed) patients were treated. The numbers of external megavoltage treatment machines were 2,397 in the United States and 494 in Japan. The numbers of full time equivalent (FTE) radiation oncologists were 2,335 in the United States and 366 in Japan. Only 15% of United States facilities and 11% of Japan facilities complied with the narrow blue book guideline for the patients per FTE radiation oncologist (200-250), while the most common ratio was 151-200 patients/FTE in the United States and 51-100 in Japan. In Japan, more than 60% of institutions were staffed by a part-time radiation oncologist (FTE < 1.0). Between geographic regions, there was variation in the percentage of cancer patients treated with radiation therapy for both the United States (42-56%) and Japan (6-25%). CONCLUSION: There is a major difference in the usage of radiation therapy for treating cancer between the United States and Japan with 49% of all new cancer patients treated in the United States and approximately 15% treated in Japan. Equipment structure in the United States is more complete than in Japan with important differences in treatment simulators, treatment planning computers, and support personnel. High dose rate intracavitary radiation is commonly available in Japan and there are geographic differences in radiation oncology utilization in both countries.

Present status of fast neutron therapy in Asian countries.

In Asian countries, fast neutron therapy was first introduced at the National Institute of Radiological Sciences (NIRS), and followed by the Institute of Medical Science (IMS), Tokyo University, and Korea Cancer Center Hospital (KCCH). At NIRS, 2,129 patients were treated with d(30 MeV)+Be neutrons between 1975 and 1994. There were 274 patients referred for the treatment with P(50.5 MeV)+Be neutrons at KCCH during the period of 1986 through 1992. Unfortunately, fast neutron therapy performed at IMS was discontinued in 1991, where 458 patients had been treated with d(14 MeV)+Be neutrons since 1976. At NIRS, a vertical beam with multileaf collimator system was used for treatment of patients referred. The results showed that local control rates were 79% (19/24), 53% (14/26), and 89.3% (50/56) for carcinoma of the salivary gland, osteogenic sarcoma and carcinoma of the prostate, while complications for those were found to be 8.8, 8.3 and 17.8%, respectively. In the treatment of carcinoma of the lung, results were better for patients with adenocarcinoma than those with squamous cell carcinoma. Of 32 patients suffering from Pancoast tumor, 14 achieved local control, whereas 2 of 32 patients developed complications. On the other hand, salvage surgery was required in the treatment of malignant melanoma. In the treatment of malignant glioma, dose localization has to be improved in the target area to confirm local control. Experiences performed at KCCH have shown that, of 53 patients suffering from unresectable primary or recurrent rectal carcinomas, 28 achieved local control. It was concluded from the experiences with fast neutrons in Asian countries that adenocarcinomas as well as slowly growing tumors are indications for fast neutrons and that dose localization has to be improved in order to advance high LET radiation therapy. Clinical trials with 70 MeV protons started at NIRS in 1979, where the aim of study has been focused on treatment of choroidal melanoma, whereas, at Tsukuba University, 250 MeV protons have been used in the treatment of tumors deeply seated. Based on experiences of fast neutrons and protons, clinical trials with heavy ions initiated at NIRS in October 1994. Clinical studies with high LET radiations will be performed by using heavy ions in order to pursue indications of particle radiation therapy.

[A case report of annuloaortic ectasia with coarctation of the aorta and "high take off" of the right coronary artery].

A 21-year-old male who had annuloaortic ectasia with coarctation of the aorta and "high take off" of the right coronary artery underwent two stage operations. A bypass operation using an artificial graft was performed for coarctation of the aorta at the first procedure. The second procedure, Cabrol's operation, was performed on 83rd day after the first operation. At the second operation we found "high take off" of the right coronary artery. The right coronary artery originated about five centimeters above the rim of the left sinus of Valsalva. Post-operative cause was uneventful. Annuloaortic ectasia combined with coarctation of the aorta and "high take off" of the right coronary artery is very rare in the literature.

Repopulation of tumour cells following irradiation with X-rays or low energy neutrons.

The repopulation of C3H mouse mammary carcinoma cells following X-ray or fast neutron irradiation was investigated in vivo using TCD50 as an endpoint. Tumours in the C3H mouse leg were irradiated in air with an X-ray dose of 9.6, 28.8 or 48.0 Gy, or a neutron dose of 2.6 or 5.2 Gy, and, various times thereafter, graded X-ray doses were given under hypoxic conditions to determine TCD50. Substantial recovery from sublethal and potentially lethal radiation damages was observed within 48 h following X-ray irradiation, and less recovery was found after neutrons. The effective number of tumourigenic cells was calculated at the time of the second irradiation using the TCD50 equation based on the multitarget model. The effective cell doubling time following X-rays depended on radiation dose. Repopulation appeared to be faster after small and intermediate X-ray doses (9.6 and 28.8 Gy) than after the largest dose, but substantial division delay was observed after the largest X-ray dose. A significant finding was that the tumour cells treated with a neutron dose, either 2.6 or 5.2 Gy, appeared to repopulate slightly more rapidly than those irradiated with X-rays, and the doubling times following two different neutron doses were not significantly different. These results suggest the use of a short overall treatment time for the high LET radiotherapy, and that caution must be exercised if the high LET radiation is given before photon doses.

Fast-neutron radiotherapy of nonsmall cell-carcinoma of the lung.

To determine the efficacy of fast neutron (FN) for the treatment of non-small cell lung cancer, 112 patients with histologically proven adenocarcinoma or squamous cell carcinoma at a limited stage were studied to evaluate local control and survival, after treatment with either FNs or photons alone. The local control rate of adenocarcinoma in FN-treated patients attained 50%, which was significantly higher than that (<10%) of squamous cell carcinoma in FN-treated patients or that of both histological types of carcinoma in patients treated with photons alone. In accordance with this, the 5-year survival rate for the FN-treated patients with adenocarcinoma was significantly higher than that for FN-treated patients with squamous cell carcinoma or that for photon-treated patients with both histological types of disease. The present study clearly suggests the usefulness of FN in the treatment of adenocarcinoma of the lung, though it was a non-randomized trial.

Antitumor activity of Langerhans cells in radiation therapy for cervical cancer and its modulation with SPG administration.

Correlations between infiltration of Langerhans cells (ILC) in tumor tissues and radiation curability were investigated in 449 patients with cervical cancer treated with radiation alone, including 390 squamous cell carcinomas and 59 adenocarcinomas. No significant difference in prognosis was noted in stage I, II, and IV squamous cell carcinomas between positive and negative ILC. However, in the patients with stage III squamous cell carcinoma, a significantly better survival was observed for patients with ILC than for those without, 10 year survival rates being 78% vs. 54%, P < 0.01. In adenocarcinoma, the patients with ILC also showed significantly better survival than those without ILC, the 10 years survival rates being 45% vs. 25%, P < 0.025. An analysis of failure patterns following radiation treatment demonstrated that the favorable prognosis in patients with ILC in squamous cell carcinoma was due to improvement of local control rates and somewhat lower metastatic rates, whereas in adenocarcinoma it was only due to better local control rate. The ILC was significantly associated with T-cell infiltration in tumor tissues. The immunological stimulation with Sizofiran in 20 patients led to an augmentation of ILC in tumor tissues. The present study suggests that the ILC in cancer tissues improves local response to radiation treatment partly by T-cell mediated anti-tumor activity.

Fast neutron therapy for malignant gliomas--results from NIRS study. National Institute of Radiological Sciences.

The results of combined radiotherapy with fast neutrons and photons for 39 malignant gliomas were analyzed. The patients consisted of 16 astrocytoma grade 3 and 23 glioblastoma multiforme. There were two kinds of combination methods which were either "boost therapy" or "mixed beam therapy" with a localized fast neutron field. The average dose of fast neutrons was 569 cGy (n, gamma) and that of photons was 36.86 Gy. The median survival of astrocytoma grade 3 was 15.5 months, and that of glioblastoma multiforme was also 15.5 months. With respect to the combination methods, there was no difference between the boost regimen and the mixed beam regimen. This result seems to have no impact on survival compared to other reports. Patients' ages, surgical debulking procedures, and photon doses were listed as significant prognostic factors, but doses of fast neutrons had no prognostic significance for survival. Because there were no moderate or severe complications for the brain except permanent epilation in all cases, neutron dose escalation study with a localized field will be recommended.

Combination therapy of local administration of OK-432 and radiation for esophageal cancer.

Local administration of OK-432, a biological response modifier, was combined with radiation in 30 patients with esophageal cancer as a pilot study. Complete response was obtained in 22 of 30 patients (73.3%); and partial response was obtained in the remaining eight cases (26.7%). Complete response was obtained in all eight patients with a tumor less than 5 cm in length. In the group with tumors 5-10 cm in length, complete response was obtained in 11 of 14 cases (78.6%); and partial response was obtained in 3 of 14 cases. In the group with a tumor length of more than 10 cm, complete response was obtained in 3 of 8 cases (37.5%); and partial response was obtained in 5 of 8 cases. One-year, 2-year, and 3-year survival rates of the 30 patients, including four patients who died of other diseases, were 67.9%, 40.8% and 29.0%, respectively. This new combination therapy may contribute not only to local control, but also to survival.

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.

[Entrapment of broken guidewire in the right coronary artery during percutaneous transluminal coronary angioplasty].

The distal 2 cm end of guidewire was broken and retained in the right coronary artery (RCA), during percutaneous transluminal coronary angioplasty for 99% narrowing of the middle RCA in a 53-year-old male patient with effort angina. Because of the stable condition of the patient, elective A-C bypass surgery was performed successfully 2 weeks after this event. However, the broken end of guidewire was not found out in the opened RCA lumen. One and a half year postoperatively, the patient is doing well while the guidewire remains in the same position.

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.

[A case report of redo A-C bypass for MCLS performed 13 years after initial surgery].

This is the first report of re-aortocoronary bypass for Kawasaki's disease. The patient is a 22-year old female. She was afflicted with Kawasaki's disease at the age of 6 and had the symptom of angina pectoris at the age of 9. She went through the first aortocoronary bypass, to the left anterior descending artery (LAD) and the right coronary artery (RCA) with saphenous vein graft (SVG). After the first operation, the graft to LAD occluded totally, but she remained asymptomatic and well for 11 years. She had a sudden recurrence of anginal attack at the age of 20. The examinations confirmed ischemia of the anterior wall (LAD area) and the lateral wall (LCX area). Coronary angiography revealed patent SVG with a moderate sign of sclerotic change. We decided on re-aortocoronary bypass, left mammary artery to LAD and gastroepiploic artery to LCX, when she was 22-years old. LIMA was anastomosed to LAD, but LCX was not revascularized, because LCX was not identified and exposed in the operation. In spite of incomplete revascularization, postoperative stress ECG test was negative. Tl-myocardial scintigram confirmed no ischemia of the anterior wall and greatly reduced ischemia in the lateral wall. She became asymptomatic and returned to normal life.

[Normal tissue tolerance to high LET radiotherapy].

Based on the clinical evaluations about over 1800 patients who had been treated with fast neutrons at NIRS, the radiobiological properties of high LET radiations were discussed. The most favorable clinical results by fast neutron treatment had been revealed in such diseases as follows; salivary gland tumors, prostate cancer, Pancoast type lung cancer, osteosarcoma, soft tissue sarcoma. The characteristics of these tumors as to the radiobiological properties and the dose distribution are, 1) relatively slow growing tumors and higher RBE for tumor tissue, and 2) capability of correct delivery of a big radiation doses to the target, without any severe radiation complications. Normal tissue tolerance (NSD formulas) for each tissues were also discussed.

Analysis of bone scintigram data using speech recognition reporting system--data analysis with speech recognition system.

Five hundred eighty bone scintigram reports were stored using a voice pattern recognition system in a general-purpose, middle-sized computer (ACOS-650). Bone scintigraphy carried out in our institute was examined by analyzing these data. The results of the examination showed that the introduction of this system made it possible to analyze all the data quickly. Before the introduction of this system, the data able to be analyzed had been restricted because of their complexity. The results also showed that this system would be useful for understanding the examinations carried out in the whole hospital as well as for analyzing metastatic tumors and the number of patients receiving examinations. Furthermore, this system would be helpful in the logical analysis of reports prepared by doctors.

[New combined therapy of radiation and local administration of OK-432 for esophageal cancer--local control rate and two-year survival rate].

We devised new combination therapy of radiation and local administration of OK-432 and performed for 26 patients with esophageal cancer between March, 1987 and December, 1988 as a pilot study. The average age was 73 years. Among 26 patients, male were 20 and female were six. Patients were irradiated at the schedule of under 2 Gy/day and the dose of TDF (time, dose and fractionation factor) 100 totally. OK-432, 10KE was endoscopically administered around cancer lesion at the beginning of the radiotherapy, and two weeks later, 5KE was given in the same manner. Complete response was obtained 20 out of 26 cases (77%) and partial response was obtained in the remaining six cases (23%). All six patients with tumor length less than five cm showed complete response. All 16 patients who could not eat food orally before treatment, became to take food enough orally after the treatment and could discharge in good condition. One year and two years survival rate of 26 patients by Kaplan Meier method were 67.4% and 47.2%, respectively. Six patients with tumor length less than five cm, are all alive without a sign of recurrence. This combination therapy will improve not only the response rate and the survival rate, but also the quality of life of patients with esophageal cancer.

Characteristics of malignant melanoma cells in the treatment with fast neutrons.

The radioresistance of malignant melanoma cells has been explained by the wide shoulder of the dose-cell-survival curve of the cells exposed to photon beams. Fast neutrons, 30 MeV d-Be, were used to treat patients who had malignant melanoma in order to confirm the biological effects of high linear energy transfer (LET) radiation for tumor control. Seventy-two patients suffering from malignant melanoma participated in the clinical trials with fast neutrons between November 1975 and December 1986. Of 72 patients, 45 had melanoma of the skin, 20 had melanoma of the head and neck, and seven had choroidal melanoma. Five-year survival rate of the patients who had previously untreated melanoma of the skin was 61% and for patients who received postoperative irradiation, it was 35.7% whereas no patients who had recurrent tumor survived over 4 years. Of 22 patients who had melanoma of the skin, stage I, local control in four cases was achieved by irradiation alone, whereas local control was achieved in 17 of 18 patients who required salvage surgery after fast-neutron therapy. The results of pathological studies performed with specimens obtained from salvage surgery have shown that melanoma cells growing in intradermal tissue are radio-resistant, compared with cells growing in intraepidermal tissue. This might suggest that melanoma cells acquire radioresistance when the connective tissue is involved. Five-year survival rate of the patients who had locally advanced melanoma of the head and neck, previously untreated, was 15.4%. Radiation therapy with accelerated protons was suitable for patients suffering from choroidal melanoma.