Shigematsu N
Department of Radiology, Keio University, School of Medicine.
Nihon Igaku Hoshasen Gakkai Zasshi. 1990 Sep 25;50(9):1139-46.
This study was carried out to determine the effect of local irradiation of the NFSa tumors on the incidence of lung metastases. The spontaneous lung metastases were found in those animals whose tumors had grown in size bigger than 10 mm in diameter. The incidence of metastases and the number of lung nodules were increased in those animals of irradiated group when compared to those of control group with the same size. This is probably because the irradiation of tumors resulted some retardation in their growth and thus, the irradiated tumors took a longer time to reach a given size than those unirradiated control tumors. The incidence of spontaneous lung metastases was significantly reduced by subcutaneous administration of OK-432 (2.5KE/mouse) locally into the surroundings of the tumor immediately after irradiation. The administration of OK-432 after the metastasis development was no longer effective. Both of intraperitoneal and subcutaneous administrations of OK-432 into opposite side of unirradiated thigh showed no suppression of metastasis. These results suggest that an appropriate immunostimulation combined with radiotherapy may be important for the suppression of tumor metastases.
本研究旨在确定对NFSa肿瘤进行局部照射对肺转移发生率的影响。在肿瘤直径生长超过10毫米的动物中发现了自发性肺转移。与相同大小的对照组动物相比，照射组动物的转移发生率和肺结节数量增加。这可能是因为肿瘤照射导致其生长出现一定程度的迟缓，因此，与未照射的对照肿瘤相比，照射后的肿瘤需要更长时间才能达到给定大小。照射后立即在肿瘤周围局部皮下注射OK-432（2.5KE/小鼠）可显著降低自发性肺转移的发生率。转移发生后注射OK-432不再有效。在未照射大腿的对侧进行腹腔内和皮下注射OK-432均未显示出对转移的抑制作用。这些结果表明，适当的免疫刺激与放疗相结合可能对抑制肿瘤转移很重要。
