[Histochemical and histomorphometric studies on growth fractions in human breast carcinoma].

Nucleolar organizer regions (NOR) can easily be recognized on paraffin sections of bioptic material with an argyrophilic stain. NORs are meant to to correlate with mitotic activity of proliferating cells. This study examine wether NOR-activity corresponds with the proliferations marker KI-67. 10 fibroadenomas and 40 invasive ductal breast carcinomas were studied. For objective tumor grading the size of the nuclei was determined morphometrically. NORs, KI-67 and nuclei sizes correlate closely in fibroadenomas. In carcinomas, however, a correlation between NORs, KI-67, and the size of the nuclei could not be found. NORs and KI-67 evidently mark different cell activities. For prognostic evaluation of malignant tumors they should therefore not be used alternatively but complementarily.