The value of expression of EGFR, telomerase and topoisomerase IIα in malignant effusion smears before and after chemotherapy.

Purpose: To evaluate the significance of expression of epidermal growth factor receptor (EGFR), telomerase and topoisomerase IIα (topo IIα) in cells of malignant effusions of patients under chemotherapy.

Methods: We studied the expression of EGFR, telomerase and topo IIα in malignant effusion smears of 95 cancer patients before and after chemotherapy. Immunocytochemical and in situ hybridization techniques were applied.

Results: Positive expression before chemotherapy of telomerase, topo IIα and EGFR was found in 64.2, 63.2 and 69.5% of the cases, respectively; the expression of these markers following chemotherapy was 43.6, 28.2 and 53.8%, respectively. The stronger prognostic factor affecting survival before chemotherapy was telomerase (p=0.0002), whereas after chemotherapy the strongest factor was EGFR (p<0.0001). A positivity for all three markers following chemotherapy was associated with shorter survival compared with positivity for only 1 or 2 markers (p<0.0001) or with a negative expression.

Conclusion: It seems that expression of EGFR, telomerase and topo IIα in malignant effusion smears is adversely affecting prognosis and survival.