EPCAM and neoplasm: Another critical point was the enrichment of tumor cells for RNA-sequencing by EpCAM: on the one hand important for direct comparability of results (removing the largely different tumor microenvironments in solid tumors and ascites), but on the other hand introducing a bias towards epithelial tumor cells, with the consequence, that mesenchymal tumor cells which completely lost their EpCAM expression were not co-enriched.