APOPTOSIS IN OPERATED SMALL-CELL LUNG-CARCINOMA IS INVERSELY RELATED TO TUMOR NECROSIS AND P53 IMMUNOREACTIVITY

The present study was undertaken to analyse the extent of apoptosis in operated small cell lung carcinoma (SCLC) by using in situ labelling of the oligonucleosomal DNA fragments by terminal transferase. The ext ent of apoptosis,vas compared with the cell proliferation activity, as determined by Ki-67 immunohistochemistry; with the volume density of necrosis (per cent), as determined by the morphometric point counting method; and with the occurrence of immunohistochemically detectable p5 3 and bcl-2 proteins. By in situ labelling, remarkably high apoptotic indices (from 0.08 to 8.10 per cent) mere seen in SCLC. A high percent age of SCLSs also showed an exceptionally high proliferation activity. Aberrant accumulation of p53 protein was seen in 37.5 per cent and bc l-2 overexpression in 50 per cent of SCLCs. Necrosis was seen in 82.5 per cent of SCLCs. The extent of apoptosis was inversely related to th e extent of tumour necrosis (P=0.05) and to p53 protein accumulation ( P=0.008). A positive association was found between the extent of apopt osis and bcl-2 immunoreactivity (P=0.02). The apoptotic indices (per c ent) correlated with the age (P<0.05) and total smoking time of the pa tients (P=0.06).