Background and objectives: Analysis of survivin RNA expression in peripheral blood as a non-invasive molecular predictor of response to neoadjuvant radiochemotherapy in patients with locally advanced cancer of the esophagus.
Material and methods: Blood samples were drawn from 29 patients with esophageal cancer prior to neoadjuvant radiochemotherapy. After extraction of cellular tumor-RNA from blood samples, quantitative expression analysis of survivin was done by quantitative real-time RT-PCR.
Results: Twenty of 29 (69%) of patients showed a minor histopathological response and 9 of 29 (31%) showed a major-response to neadjuvant radiochemotherapy. RNA expression in blood of patients was detectable for survivin in 27.6%, and in 100% for beta-actin. The mean survivin expression was not significantly different between minor- and major-responders. No significant associations were detected between survivin expression levels and patients clinical variables. A high expression level for survivin was significantly associated with a minor-response to neoadjuvant treatment (P = 0.042). Relative survivin expression levels above 0.15 were not associated with major histopathological response (sensitivity: 35%; specificity: 100%).
Conclusion: Minor-response to the applied therapy was significantly associated with a high survivin RNA expression level in patient's blood. Survivin appears to be a specific non-invasive predictor of response to neoadjuvant therapy in esophageal cancer.