MICROCALORIMETRIC MEASUREMENTS CARRIED OUT ON ISOLATED TUMOROUS AND NONTUMOROUS TISSUE SAMPLES FROM ORGANS IN THE UROGENITAL TRACT IN COMPARISON TO HISTOLOGICAL AND IMPULSE CYTOPHOTOMETRIC INVESTIGATIONS

In this comparative study, microcalorimetric measurements were carried out on a total of 96 tumorous and nontumorous tissue samples taken fr om organs of the urogenital tract using a thermal activity monitor (TA M). Changes in the heat emission of the tissue samples were measured a t 1-min intervals and graphically displayed as a function of time. The aim of the study was to compare the microcalorimetric results with im pulse-cytophotometric and histological findings and provide evidence f or the metabolic activity of tumorous and nontumorous tissue. In order to obtain the variation in metabolic activity, the maxima (P-max) of the curves were determined as a value of the maximum thermal power of a tissue sample, the mean values (P) were determined by the mean therm al power and the contour integrals (W) were defined by the behavior of the energy reserves and their mobilization. The first part of the stu dy was carried out to investigate whether tumorous and nontumorous tis sue samples differ in general according to their metabolic activity. W e discovered, using the parameters described above, that in general tu morous tissue exhibited a higher metabolic activity than nontumorous t issue samples. For example, both W and P in tumorous prostate tissue s amples were eightfold higher and the (P-max) value was 8.4-fold higher than in normal tissue. Additional investigations on testicle and kidn ey tissues were performed to find a possible correlation between micro calorimetric results and histological grading. We found that an increa sing malignancy correlated with a higher metabolic activity of the tis sue. Based upon these results we were able to differentiate the variou s histological gradings of these tumorous tissues by microcalorimetric measurements. The results show it is possible to differentiate betwee n normal and tumorous tissue samples by microcalorimetric measurement based on the distinctly higher metabolic activity of malignant tissue. Furthermore, microcalorimetry allows a differentiation and classifica tion of tissue samples into their histological grading. With the help of microcalorimetry, it might be possible in future to detect and reco rd the metabolic processes of isolated tissue structures and changes i n these activities as a result of medical intervention such as cytosta tic treatment.