[Apoptosis and pathomorphology of renal tumors]

An analysis was performed of renal tumours in 60 patients with kidney cancer and in two patients with oncocytoma. A study was made against morphological investigations on tumour tissue apoptosis and proliferation. The degree of DNA fragmentation in a biopsy specimen proved to be of value as a guide to detection of apoptosis; the activity of proliferation was studied by the MTT method using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Apoptosis has been ascertained in 59 out of 62 cases. The degree of apoptosis (the percentage of DNA fragmentation) was between 0 to 56.2%, the apoptotic cell count tending to decrease with the stage of the tumour process. The extent of cell proliferation was 0.8 to 22.6%; in those patients in the T1N0M0 stage it was much lower than in patients in the T2N0M0/T4N x M1. There was no significant difference between the level of apoptosis, proliferation and spreading of metastases. With growing tumour and degree of its differentiation apoptosis comes to be diminished but the activity of proliferation is noted to be on the increase, which event favours spread of the tumour beyond the organ.