Whole-body hyperthermia

In the fifth part of this article (Section VI), heat transfer in tumors is discussed with application in thermography and hyperthermia. Similar to mass transfer, two theoretical approaches—lumped and distributed parameter—to describing heat transfer in normal and neoplastic tissues are described and used to predict temperature distributions during normo-and hyperthermia. Various techniques to induce localized and whole-body hyperthermia are also summarized. 

Depending upon the surface area or volume heated, hyperthermia can be divided into three categories (i) local, (ii) regional, and (iii) whole-body. In local hyperthermia, tumor mass and minimum surrounding tissue are heated in regional hyperthermia, usually the limb containing the tumor mass is heated and in whole-body hyperthermia (WBH), the temperature of the host is elevated. 

The temperature of a part of the body (or even the whole body] can be raised a few degrees higher than normal, it helps other cancer treatments such as radiation, immunotherapy, or chemotherapy work better. This is called regional hyperthermia or whole-body hyperthermia. 

Finally, we mention several current applications somewhat outside of biochemistry in the usual sense. Thermography has slowly been coming to the fore. Many of the problems associated with the analysis of thermograms were treated at the Fifth International Symposium on Temperature (Plumb, 1972) in 1972 and new applications were discussed at the Sixth Symposium (Schooley, 1982) in 1982. Of perhaps more current interest is the greatly expanded interest in temperature measurement in hyperthermia and hypothermia. A recent New York Academy of Sciences conference has done an excellent job of reviewing this (Ann. N.Y. Acad., 1980). Cetas also wrote a general review of thermometry in this field (Cetas, 1968). Perhaps the most exciting new method in thermometry is that of optical fluorescence, which we described earlier. Catheters, whole-body scanners, etc., have been made for use with this method. At this point, 0.01°C is probably the least imprecision that can be obtained with the commercial instrument (Luxtron), with data obtained every 0.1 sec. Improvements are likely, however, as needs are made known to the company. 

During hyperthermia, terms representing the heat input to a specific tissue or whole body must be added to the proper system equation(s). For example, during whole-body or local hyperthermia induced by radiofrequency currents, microwaves, or ultrasound, a heat-generation term is added to the section of the body being heated. During hyperthermia with blood perfusion, the afferent blood temperature is set at a desired value, and the efferent blood is circulated to the central blood pool, or to the extracorporeal device used for heating the blood. Suitable numerical... 

Chamy, C. K., Hagmann, M. J., and Levin, R. L., 1987, A Whole Body Thermal Model of Man during Hyperthermia, IEEE Trans. Biomed. Engineering, 34(5) 375-387. 

Early stage cancer entities are usually localised, but in the case of deep tissues, access is awkward and a therapeutic heat dose is difficult to be conveniently delivered. The activation issues related to the infrared radiation used in whole-body and local hyperthermia techniques exemplify this... 

Under conditions of local hyperthermia, where the heated volume is small compared to the body as a whole, the blood perfusion rate may undergo complex changes. Based on experimental data the following correlations have been suggested [46,47] for muscle... 

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