Immunohistochemistry-based prognostic biomarkers in NSCLC: novel findings on the road to clinical use?

Prognostication of non-small cell lung cancer is principally based on stage, age and performance status. This review provides an overview of 342 potential prognostic biomarkers in non-small cell lung cancer described between January 2008 and June 2013, evaluating the association between immunohistochemical protein expression and survival endpoint. Numerous studies proposed prognostic biomarkers, but many were only evaluated in a single patient cohort, and a large number of biomarkers revealed inconclusive findings when analyzed in more than one study. Only 26 proteins first described after 2008 (ALDH1A1, ANXA1, BCAR1, CLDN1, EIF4E, EZH2, FOLR1, FOXM1, IL7R, IL12RB2, KIAA1524, CRMP1, LOX, MCM7, MTA1, MTDH, NCOA3, NDRG2, NEDD9, NES, PBK, PPM1D, SIRT1, SLC7A5, SQSTM1 and WNT1) demonstrated a consistent prognostic association in two or more independent patient cohorts, thus qualifying as promising candidates for diagnostic use. Raised quality standards for study design and antibody validation, and integration of preclinical findings with clinical needs are clearly warranted.