Introduction: Cyfra 21.1 are soluble cytokeratin 19 fragments present in several biological fluids. The aim of this work was to study cyfra 21.1 cytosolic levels in lung adenocarcinomas and their possible correlation with other clinical-biological parameters.
Patients and methods: Cyfra 21.1 was determined, using an immunoradiometric assay (CIS BioInternational. France), in 58 tissue samples of lung adenocarcinomas patients. Other parameters included in the study were the following: clinical stage, histological grade, ploidy, S-phase cellular fraction, as well as cathepsin D, CA 125 and hyaluronic acid levels in cytosols. Likewise, AH, erbB2 oncoprotein, CD44s, CD44v5 and CD44v6 levels in cell surfaces were assayed.
Results: Cyfra 21.1 cytosolic levels oscillated between 24.8 and 6,774 ng/mg prot. (median 1,147.5) and were higher (p:0.00074) than those observed in 16 normal lung samples of the same patients. We did not observe any statistically significant differences in cyfra 21.1 values when clinical stage, ploidy, S-phase and histological grade were considered. When lung adenocarcinomas were classified according to cyfra 21.1 positivity, using 1,499 ng/mg prot. as cut-off, which represents the 75th percentile of the whole group, we noted that positive cases had higher levels of cathepsin D (p:0.00218), cytosolic hyaluronic acid (p:0.02947), erbB2 protein (p:0.06272) and CA 125 (p:0.07243) than negative carcinomas.
Conclusions: These results suggest the possibility that high cytosolic cyfra 21.1 levels could be associated with a poor outcome in lung adenocarcinomas.