PTPRC and pancreatic neoplasm: To improve the detection rate, immunostaining for cytokeratin was used to detect CTCs; immunostaining of CK, CD45, DAPI, and CEP8/FISH yielded sensitivities and specificities of 68.2% and 94.9% in one pancreatic cancer study (Zhang et al., 2015) and 88% and 90% in another, respectively (Gao et al., 2016).