CEACAM5 and adenocarcinoma: As no one marker exhibits a 100% specificity, guidelines recommend a combination of at least two positive mesothelial markers (calretinin, cytokeratin 5/6, Wilms tumour 1 and D2-40) and at least two negative adenocarcinoma IHC markers (thyroid transcription factor 1 (TTF1), carcinoembryonic antigen (CEA) and Ber-EP4) (see Table 1) [1].