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Recently, total body irradiation (TBI) is being used as a method of preparation for bone marrow transplantation (BMT). However, many variations exist in the TBI procedure, such as the irradiation technique, total dose, dose rate and dose fractionation. In TBI treatment, it is important to apply a homogeneous dose to the total body, and avoid interstitial pneumonitis and cataracta. Therefore, we applied a four-field technique using 10 MV X-rays with a shield for lungs and eyeballs, and employed tissue compensators and bolus to obtain a homogeneous dose distribution. The midpoint doses in 12 positions of the total body have been achieved within±10% of that of the pelvis with the use of this technique. Also, this TBI technique is capable of accurately controlling absorbed doses to the lungs and eyes.

In radiation therapy of thorax region, it is necessary to apply absorbed dose correction for heterogeneity tissuse of lungs. Practically, however, it is not easy to do an accurate absorbed dose correction. We made a basic experiment for absorbed dose correction of heterogeneity tissue of lungs using thorax phantom for 10 MV X-rays, and evaluated the accuracy of depth dose calculation algorithms for its tissue which are available in conventional, commercial-based treatment-planning systems. Depth dose on the central axis in lung for small field of 5×5(cm)^2 was reduced by about 10% due to loss of lateral electronic equilibrium. Dose correction factor of heterogeneity was insensitive to the thickness of the build-up layer of this phantom if there was a longitudinal electronic equilibrium. The equivalent TAR (tissue-air ratio) method gave the greatest accuracy for dose calculation algorithms, of lungs whose error was within about 3% compared to the measured values. However, for the smaller field of 5×5(cm)^2, all our methods did not consider the effects of electron scattering, so that the equivalent TAR method and the ratio of TAR method gave errors of about 15% and the power law TAR method about 6%.

Dose calculations of irregularly shaped fields can be made by the Clarkson technique, which, however requires considerable time and is thus not practical. We investigated a simple approximation method for determining field factors (F_A) and tissue-peak ratios (TPRs) for irregularly shaped fields. By this method, we approximated scatter dose by the ratio of area for an irregularly shaped field to that for the overall field (without blocking). Maximum error of equivalent square fields as determined by this method for irregularly shaped fields was-1.3% for field factors, +2.1% for TPRs and +1.4% for the F_A×TPRs.

表在性膀胱腫瘍12例において, rIL-2の腫瘍内局注を施行し, 腫瘍の消失を1例で, 50%以上の縮小を2例で認めた.すなわち有効率は25.0%であった.末梢血液免疫検査ではリンパ球IL-2 receptor陽性細胞の増加およびNK活性の増強を認めた.これら症例において, 軽度発熱を除き臨床上問題となる副作用はなかった, The present study was undertaken to assess the efficacy of recombinant Interleukin 2 (rIL-2: S-6820) in treatment of superficial bladder tumors. Three intratumor injections at a dose of 5 x 10(5) units/day via urethra, were performed every other day under endoscopic control in 12 patients with superficial bladder cancer. On the 15th day after completion of the series of injections, the tumor had disappeared in one patient and 50% regression over was observed in two other patients. Therefore, the response rate to the rIL-2 treatment in our study was 25.0%. Each tumor which responded to the therapy, was single, small and low grade. In the peripheral blood of the 12 patients, an increase in IL-2 receptor-positive lymphocytes and augmentation of natural killer activity were detected after the rIL-2 intratumor injection. There were no serious side effects except for moderate fever in our study.

8症例に施行し, その後8日目に腎全摘除を施行し検討した.1)摘出腎に対する抗腫瘍効果は期待に反し軽微であったが, 腎茎リンパ節のsinus histocytosisの増強が認められた.2)末梢血においてOK-Ial陽性細胞の有意な増加と, PHAリンパ球幼若化率が変動しないにもかかわらずCon A幼若化率が低下したことより末梢血免疫能改善の可能性が示唆された.3)本剤動注後, 全例で発熱を認めたが重篤な合併症はなかった, In 8 cases of operable renal cancer, selective intraarterial infusion of the streptococcal preparation, OK-432 was performed and its cytocidal effects on the surgical specimens, which were removed on the 8th day after infusion, were investigated histopathologically with immunological parameters of the peripheral blood. The histopathological study revealed a high grade of sinus histiocytosis of the renal pedicle lymph nodes, but the anti-tumor effect on renal tumors was not so marked in any of the 8 cases. OK-Ia-positive lymphoid cells of peripheral blood were increased significantly and Con-A stimulation index of blastogenesis was lowered without any change in the PHA stimulation index after the OK-432 infusion. No serious complications of the selective intraarterial infusion were experienced except for high fever (less than 38 degrees C). In conclusion, OK-432 selective intraarterial infusion was an effective method for improving regional and systemic immunoactivity, but the cytocidal effect against tumor cells could not be confirmed histopathologically.

The present study was undertaken to assess the efficacy of recombinant Interleukin 2 (rIL-2: S-6820) in treatment of superficial bladder tumors. Three intratumor injections at a dose of 5 x 10(5) units/day via urethra, were performed every other day under endoscopic control in 12 patients with superficial bladder cancer. On the 15th day after completion of the series of injections, the tumor had disappeared in one patient and 50% regression over was observed in two other patients. Therefore, the response rate to the rIL-2 treatment in our study was 25.0%. Each tumor which responded to the therapy, was single, small and low grade. In the peripheral blood of the 12 patients, an increase in IL-2 receptor-positive lymphocytes and augmentation of natural killer activity were detected after the rIL-2 intratumor injection. There were no serious side effects except for moderate fever in our study.

In 8 cases of operable renal cancer, selective intraarterial infusion of the streptococcal preparation, OK-432 was performed and its cytocidal effects on the surgical specimens, which were removed on the 8th day after infusion, were investigated histopathologically with immunological parameters of the peripheral blood. The histopathological study revealed a high grade of sinus histiocytosis of the renal pedicle lymph nodes, but the anti-tumor effect on renal tumors was not so marked in any of the 8 cases. OK-Ia-positive lymphoid cells of peripheral blood were increased significantly and Con-A stimulation index of blastogenesis was lowered without any change in the PHA stimulation index after the OK-432 infusion. No serious complications of the selective intraarterial infusion were experienced except for high fever (less than 38 degrees C). In conclusion, OK-432 selective intraarterial infusion was an effective method for improving regional and systemic immunoactivity, but the cytocidal effect against tumor cells could not be confirmed histopathologically.