Prognostic value of synaptophysin and chromogranin a expression in patients receiving palliative chemotherapy for advanced non-small-cell lung cancer.

BACKGROUND Chemotherapy is the principal treatment method for patients with advanced non-small-cell lung cancer (NSCLC). Treatment with platinum-based and novel chemotherapeutic regimens, compared to monotherapy, slightly increases the response rates to 20-40%. The predictive and prognostic values of molecular factors are highly variable; however, data on clinical-demographic factors are still burdened by significant limitations. OBJECTIVES The aim of this study was to assess the prognostic value of synaptophysin and chromogranin A protein expression in patients receiving palliative chemotherapy for advanced NSCLC. METHODS The study population consisted of 23 women and 116 men. The median age was 57.3 years. Expression of synaptophysin and chromogranin was assessed using a two-step model of immunohistochemical staining. Level 0 represented lack of activity, while level 1 represented its expression. RESULTS Expression of synaptophysin and chromogranin A was observed in 12 (8.6%) and 5 (3.6%) patients, respectively. The risk of death was significantly lower in patients with expression of synaptophysin (p = 0.008) and chromogranin A (p = 0.014). The 12- and 24-month survival rate of patients with synaptophysin expression was 64% (95% CI 0.35-0.93), while for patients without expression it was 46% (95% CI 0.36-0.56) and 16% (95% CI 0.07-0.25), respectively. The 12- and 24-month survival rate of patients with chromogranin expression was 80% (95% CI 0.44-1.00), while for chromogranin A-negative patients it was 47% (95% CI 0.37-0.57) and 19% (95% CI 0.10-0.28), respectively. We did not observe associations between expression of synaptophysin and chromogranin A and the other typical prognostic factors. CONCLUSIONS Expression of synaptophysin and chromogranin A was associated with a longer median overall survival and might have prognostic value. These results should be confirmed in a prospective study.