| Research Abstract |
As for hyperthermia in Japan, cases of capasitive heating using RF wave presently account for the majority, but selective heating is difficukt and there still is a room for study as to hyperthremia for gastrointestinal cancers which are located deep in the abdominal cavity. In the present study we prepared liposomal ferromagnetic particles (hereinafter refered to as HP-LM) by cvering Fe_3O_4 particles of which mean particle size is 15 nm with lipid molecular membrane of liposome and having hem atoporphyrin, the purpose of developing a selective heating method for deep tumors. Furthermore, VX-2 tumor cells were implantd in the lower legs of rabbit, and HP-LM was administered intraarterialy, andhigh frequency inductive heating was done. The intraarterial administration group, as compared with the nonadministration group, showed a significant rise in temperature in tumors as wellas the tumor-growth-inhibiting effects. However, repeated administration of HP-LM was considered necessary toprevent the growth of tumorsfor a long period of time. Therefore, high frequency inductive heatingwas done by administrating HP-LM repeatedlyfrom a reservoir for intraarerial injection, with the tumor grown 4.2 times after 21 days in the nonadiministration and nonheating group, and 1.7 tines after 21 days in the repeated administration and heating group. When the tumor was ecamined histologically, magnetic particles were accumulated in the tumor tissue. However. accumulation in the reticuloendot helial organs was also high, so a study on the metabolic route is the subject of future study.
|
