CEACAM6 and neoplasm: The associated sensitivity of 87.5% is much better than the 53% initially published for serum CA19-9 in the general population, while the specificities were similar (69.1% vs. 76.0% respectively).[37] Previous studies have shown that CEACAM6 is overexpressed in IHCC tumor tissue, and this is reflected by higher biliary CEACAM6 levels (25.0 vs. 7.5 ng/ml for benign disease, p = .051).