[Value of the tumor colony assay in therapy planning in malignant ovarian tumors].

The aim of our study was to determine the clinical value of the human tumour colony assay for the treatment of patients suffering from advanced malignant ovarian tumours. Using this in vitro culture system the growth and chemosensitivity of clonogenic tumour cells could be studied. Cultures were obtained of only 52.6% of the 133 tumour samples; only 33 of 70 assays showed a sufficient growth of colonies. However, the significance of the stem cell assay for clinical use is represented by the prediction of drug resistance. In 17 trials the assay had a 67% true positive rate and a 100% true negative rate for predicting drug sensitivity and resistance, respectively. Apart from the methodical errors inherent in this method, the false positive prediction of drug sensitivity might be caused by the heterogeneity of the tumour.