NUCLEOLAR ORGANIZER REGIONS (AG-NORS) - A PROGNOSTICALLY USEFUL FACTOR IN RECTAL-CARCINOMA

Paraffin-embedded tumour tissue of 45 cases of rectal adenocarcinoma with intended radical surgery and without postoperative treatment (various Dukes stages, UICC stages, and WHO tumour grades) were stained by means of an argyrophil technique in order to determine the number and distribution pattern of the so-called silver stained nucleolar organiser regions (Ag-NORs). - These findings were correlated with the clinical outcomes of the respective patients. Our study indicates that the number of dispersaly distributed Ag-NORs demonstrated in the tumour cell nuclei is a reliable parameter in regard to the patients prognosis. Findings of more than four scattered Ag-NORs per nucleus are suggestive for subsequent tumour recurrence and for development of metastases. In an univariant lifetable analysis, the mean number of scattered Ag-NORs (chi2 = 19.1, p = 0.0001) is strongly related to cancer specific survival, whereas staging of the tumour according to the UICC system (chi2 = 10.4, p = 0.006) and Dukes classification (chi2 = 11.1, p = 0.01) remained less significant. It is concluded that the number of dispersed Ag-NORs can be useful as a prognostic criterion in rectal carcinomas and may even be used in future for pre- and postoperative management of these cancer patients.