Abstract
T. P. T. staining is a supplementary diagnostic procedure for the detection of carcinoma of the uterus, based upon its varying stainability of endogenous dehydrogenase activity in the cells.
In order to clarify an underlying mechanism of the histochemical reaction, the biochemical and histochemical studies were done, using Neo-tetrazolium chloride as an indicator of the enzyme activity, on both the cervical tissues and vaginal smears of cancer and non-cancer patients.
In respect to succinic dehydrogenase activity, it appeared to be augmented 2.8 times in the carcinomatous cells than in the non-carcinomatous cells, and 2.4 times in the cancerous smears than in the non-cancerous smears. Also, in regard to endogenous dehydrogenase activity, it seemed to be increased 17 times in malignant cervical tissues than in the non-malignant tissues.
Although a striking decrease in the activity was observed in the vaginal smers due possibly to its unstable reaction, it showed to be 1.6 times higher in the cancerous smears than in the non-cancerous smears. Furthermore, the exfoliative cells in the cancer patients, such as cancer cells, non-cancer cells, leucocytes and microorganisms showed a higher activity compared with those in the non-cancer patients.
From the evidence above described, it is assumed that the T. P. T. positive reaction observed in the cancer patients might be due to the elevated activity in the various cells and the microorganisms and the concurrent elevation of the vaginal pH approximately close to the optimal pH for the stainability of succinic dehydrogenase. Thus, in the carcinomatous cells, T. P. T. is highly deoxidized with a resultant formation of formazan which makes its appearance in the necrobiotic cells or lipid-phagocytic cells.
