Prospective validation of serum CYFRA 21-1, beta-2-microglobulin, and ferritin levels as prognostic markers in patients with nonmetastatic nasopharyngeal carcinoma undergoing radiotherapy.

Abstract

Patients with undifferentiated nasopharyngeal carcinoma (NPC) have elevated serum levels of CYFRA 21-1 (CYFRA), ferritin, and beta-2-microglobulin (beta2M) compared with healthy control individuals. The prognostic value of these markers has never been validated prospectively. Paired serum samples from 160 patients with newly diagnosed, nonmetastatic, undifferentiated NPC were collected before radiotherapy (RT) and at 4-6 weeks after the completion of RT. Pre-RT and post-RT levels of serum CYFRA, ferritin, and beta2M were analyzed and correlated with overall survival (OS), progression-free survival (PFS), time to locoregional recurrence, (TLR) and time to distant recurrence (TDR). The results of pre-RT and post-RT plasma Epstein-Barr virus (EBV) DNA levels available from a previous study were included in a Cox regression model together with age, tumor (T) classification, and lymph node (N) classification. Sixty percent of patients had International Union Against Cancer Stage III-IV disease. At a median follow-up of 116 weeks (range, 37-239 weeks), 38 patients had disease progression. On multivariate analysis, pre-RT CYFRA and post-RT EBV DNA levels were independent predictors of poor OS, post-RT EBV DNA level and N classification predicted poor PFS and TDR; and only T classification predicted TLR. Patients who had pre-RT CYFRA levels > or = 1.5 U/mL were more likely to die (hazard ratio, 1.18; 95% confidence interval, 1.10-1.26) compared with patients who had pre-RT CYFRA levels < 1.5 U/mL. There were no associations between age, post-RT CYFRA levels and pre-RT or post-RT serum ferritin and beta2M levels, and the survival and recurrence rates on multivariate analysis. Serum CYFRA levels taken before RT predicted reduced survival in patients with nonmetastatic, undifferentiated NPC who underwent RT.