We estimated the activity of gama-glutamyltransferase (gGT) in homogenates of 13 dysplastic and 78 human breast tumour tissues. The differences between average values calculated for dysplastic tissue, carcinoma and cystosarcoma phyllodes are small and nonsignificant, but the values fluctuate, mainly in carcinoma, in a wide range. Sometimes differing activities of gGT in various samples of the same tumour could be measured. We could find a significant difference neither between carcinoma of patients with metastases in axillary nodes and those who were regional metastases free, neither after sorting into groups according to the menopausal status. Neither we could evidence any influence of preoperative irradiation on gGT activity in carcinoma tissue. We could not find even a correlation between gGT activity in tumour tissue and in blood serum.
The gamma -glutamyltransferase activity in human breast tumours
