SMARCB1-Deficient Sinonasal Adenocarcinoma: Rare Variant of SWI/SNF-Deficient Malignancy often Misclassified as High-Grade Non-Intestinal Adenocarcinoma or Myoepithelial Carcinoma
Abstract
SMARCB1-deficient sinonasal adenocarcinoma (SNAC) is a rare variant of SWI/SNF-deficient malignancy defined by presence of unequivocal glandular differentiation and/or by presence of other features of adenocarcinoma. The tumors are mostly made up of oncocytoid/plasmacytoid tumor cells in rounded nests, trabeculae, reticular microcystic and glandular patterns, and could be misdiagnosed as high-grade non-intestinal adenocarcinoma (HG non ITAC), myoepithelial carcinoma (MC), or even yolk sac tumor.