In a sense, noninvasive thermometry is a key technology in hyperthermic treatment. Not only for the temperature control, but also for evaluation of the treatment effects it will be used effectively by observing the temperature distribution continuously. In the beginning, brief description on the various modalities of the noninvasive thermometry which have been proposed so far is given. Following the general introduction, noninvasive thermometry research using a chirp pulse microwave has been explained along with the future prospect. Present situation of the other modalities such as a noninvasive thermometry based on MRI or impedance CT has also been described briefly.

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Experimental studies on mice have made it clear that embryos are more sensitive to radiation during organogenesis than other prenatal periods. However, the teratogenic effects of hyperthemia at organogenesis in mice have yet to be described. The organogenesis stage is the most important from the viewpoint of non ionizing protection. Many physical and chemical agents in the environment can affect an embryo. Fetal deaths were classified as preimplantation, embryonic and fetal. For preimplantation deaths, all the treatment groups differed significantly from the control group and the Sham control group of implantation (P<0.001). Regarding teratogenesis, exencephaly, cleft palate, abdominal hernia, anomalies of tail, and so on were observed in the hyperthermia group treated at 192 hours post-conception (192 hpc). There was no temperature dependence though fetal body weight at the embryonic age of 18 days differed slightly but significantly between the hyperthermia and control groups. There was a difference based on gender, but this was thought to be due to physiological sexuality, not temperature.
Pregnant ICR mice at 192 hpc, the organogenesis stage of embryonic development, were treated with whole body hyperthemia of 37, 38, 39, 40, 41, and 42°C for 10 min. Embryonic mortality in the mice treated at the stage of organogenesis was higher than in the mice treated at the fetal stage. Many types of external gross malformations such as exencephaly, cleft palate and anophthalmia were observed in the live fetuses mice treated at 38.5°C. However, no malformations were observed in mice treated below 38°C. It is believed that embryos during hyperthemia are not susceptible to teratogens such as radiation and chemical agents. In this study, the sensitivity to external malformations of the fetuses of mice subjected to hyperthemia during Organogenesis was examined.

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From 1989 to 1998, seventy two patients (T3NxMO) underwent hormone therapy as initial treatments for 3 to 6 months, while twenty patients were diagnosed as hormone refractory prostatic carcinomas proven by needle biopsy pathologically. Therefore they were treated with radiation therapy. After the radiation therpy, needle biopsy of the prostate was performed again and the pathological effects were diagnosed. The ten patients revealed no viable cancer cells in the specimen obtained by needle biopsy, while the remained ten patients showed the viable cells in the biopsied specimens. These ten patients received local hyperhtermia with Thermotron RF-8 follwoing radiation therapy 5 times. The pathological findings obtained by additional needle biopsy revealed degenerative changes in the ten patients received local hyperthermia after radiation therapy. These results indicate that radiation therapy followed by local hyperhtermia is effective for the treatment of stage C hormone refractory prostatic carcinomas.

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The purpose of this study was to determine whether hyperthermia can modify the killing effects of anti-cancer drugs on cancer cells. Mouse leukemic cells (L-1210, L5178Y and M-10) were used in this study. Survival rate evaluated by trypan-blue dye exclusion test was investigated, the incorporation of Doxorubicin hydrochloride (ADR) was examined with FACScan Flow Cytometry System, and changes in cell volume were examined by measuring the cell size with Coulter Counter Channelizer. Survival fraction of L-5178Y cells from the combined treatment with hyperthermia at 44°C for 180 min and ADR was remarkably decreased in comparison with that of the control, and the cell size became smaller than that of the control. These results suggested that cell death by the treatment with hyperthermia and ADR may be apoptosis.

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The quantitative evaluation indices concerning the heating characteristics are introduced, and the heating characteristics of an interstitial array applicator composed of the coaxial-slot antennas are examined by the numerical analysis. It is important to know how the blood flow and the input power affect the heating characteristics of the applicator. Therefore, as an example, the charts displaying the relation among the blood flow rate, the input power and these indices have been made. From such charts, understanding and the quantitative comparison of the heating characteristics of the applicator are possible without referring the graphs of the temperature distributions. Moreover, appropriate input power can be decided from such charts for arbitrary position and volume of a target tumor. The evaluation by these temperature indices is useful not only to the design of the applicator but also to the aid of the treatment planning.

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