QUANTITATIVE PATHOLOGY IN UTERINE SMOOTH-MUSCLE TUMORS - THE CASE FORTHE STANDARD HISTOLOGIC CLASSIFICATION CRITERIA

A number of nuclear morphometric factors (longest and shortest axis, p erimeter, area, roundness coefficient) as well as the number of mitose s per 20 high power fields with an x40 objective (mitotic index) and t he volume corrected mitotic index (VCMI) have been assessed in 33 uter ine smooth muscle tumours (14 leiomyomata, 5 leiomyosarcomata, 9 atypi cal leiomyomata and 5 tumours of uncertain malignant potential). Multi variate analysis showed the VCMI and nuclear roundness coefficient to be the two most significant prognostic factors achieving, by means of Fisher's linear discriminant function, a high percentage of correct re classification of the tumours into their respective groups. Furthermor e, VCMI was shown to be a more accurate prognostic factor than the sim ple mitotic index. The results uphold the traditional classification h istologic criteria and demonstrate the significance of VCMI as a relia ble index of mitotic activity.