EXPRESSION OF INSULIN-LIKE GROWTH-FACTOR-I RECEPTOR AND TRANSFERRIN RECEPTOR BY BREAST-CANCER CELLS IN PLEURAL EFFUSION SMEARS

Smear preparations were made from cells harvested from pleural fluid f rom 90 patients with breast cancer and stained for transferrin recepto r (TRFr) and insulin-like growth factor-I receptor (IGF-Ir) using an i mmunocytochemical technique. The results were correlated with those fr om 36 benign effusion smears. In malignant smears from the breast canc er cases TRFr was demonstrated in 84.4% of the cellular deposits and I GF-Ir in 91.1%. TRFr was demonstrated in two (11%) of the tuberculous effusion smears and in six (100%) effusions from patients with collage n disease. IGF-lr was not demonstrated in any of the smears from patie nts with benign disease. The sensitivity and specificity of TRFr stain ing were 84.4% and 77.7%, respectively, and for IGF-Ir staining were 9 1.1% and 100%, respectively. The underlying metabolic changes in the t umour cells which give rise to positive staining with these markers ar e discussed.