Besides confirming some existing non-secreted SCC markers such as TP63 and KRT6A, novel findings include using gene expression profiling analysis to identify five secreted genes, among which SPP1, CTHRC1 and GREM1 would be candidate biomarkers to identify the cancer using blood samples; additionally, SPINK1 and BMP7 would help to distinguish AC from SCC as complementary to existing SCC markers. This evidence concerns the gene KRT6A and cancer.