Baněčková M, Michal M, Laco J, et al. - Experts assessed the immunohistochemical and genetic profiles of ten cases of respiratory epithelial adenomatoid hamartoma (REAH)/seromucinous hamartoma (SH) (rare tumor-like lesions of the nasal cavity, paranasal sinuses, and nasopharynx), with serous, mucinous and respiratory components assessed discretely, and contrasted these findings with the characteristics of nine cases of low-grade tubulopapillary adenocarcinoma (LGTA). For CK7/MUC1 and SOX10, the serous component of REAH/SH was positive, likewise to LGTA. However, REAH/SH and LGTA are histopathologically and clinically distinct entities, the overlap in their morphological and immunohistochemical pecularities, implies that REAH/SH could be a precursor lesion of LGTA.