[Application of morphological and histochemical methods for evaluation of cytostatic effects on organ cultures of malignant tumors].

Histochemical and morphological methods are reported to test the sensitivity of organ culture of human and animal tumors to cytostatics. Topochemical investigations of lactate-dehydrogenase and NADH-diaphorase in organ culture of UV-induced mice tumors have shown that there is a considerably decreased enzyme activity, as compared with the controls, after application of a clinical as well as a tenfold clinical dose, especially after treatment with trenimon and 5-fluorurazil. On the other hand a decreased activity of these enzymes was found in organ cultures of tumors induced by methylcholanthren, following application of vinblastin and 5-fluorurazil. Three out of five of the investigated mammary carcinomas exhibited a markedly decreased enzyme activity when tested with cytostatics. Furthermore, a significant decrease of the enzyme activity was observed in two ovarian carcinomas and in two malignant melanomas of three tumors examined in each case. Following the administration of cytostatics, electronmicroscopical studies showed marked changes in the mitochondria in mammary carcinomas as well as in ovarian carcinomas, whereas no alterations were found in melanomas. The findings are discussed in the light of individual chemotherapy of cancer.