Low podoplanin expression of tumor cells predicts poor prognosis in pathological stage IB squamous cell carcinoma of the lung, tissue microarray analysis of 136 patients using 24 antibodies

The aim of this study was to identify clinicopathological and biological prognostic markers for patients who had undergone complete resection of pathological stage IB squamous cell carcinoma (SqCC) of the lung. A total of 136 consecutive stage IB SqCC patients fulfilled eligibility criteria, and their clinicopathological factors were evaluated. Tissue microarrays were also constracted, and immunohistochemical staining with 24 antibodies was performed. Correlations between clinicopathological factors, antibody immunohistochemical reactions, the patients’ overall survival (OS) and relapse-free survival (RFS) were evaluated. The univariate analysis showed that 70-year-old and over elderly group had a shorter OS time and RFS time than the younger group (p = 0.0086 and p = 0.0091, respectively). The univariate analysis for immunohistochemical staining showed that the podoplanin-negative group had a shorter OS time and RFS time than the podoplanin-positive group (p = 0.0106 and p = 0.0308, respectively). Multivariate analysis revealed a significant correlation between both the 70-year-old and over elderly group and the podoplanin-negative group and poor outcome (OS, p = 0.007 and p = 0.008, respectively; RFS, p = 0.008 and p = 0.024, respectively). The results showed that patient age and a novel biological prognostic marker, podoplanin, are useful for predicting a poor outcome of patients after complete resection of stage IB SqCC of the lung.