Dome-Type: A Distinctive Variant of Colonic Adenocarcinoma
(a) Panoramic view of the tumor described. A well-demarcated tumor grows into the submucosa (hematoxylin-eosin, ×10). Overlying mucosa shows adenoma with high-grade dysplasia. Invasive adenocarcinoma associated with prominent lymphoid tissue encompassing several reactive germinal centres is observed in the submucosal layer. (b) Pan-Cytokeratin highlight tumor invasion. From the advancing edge few scattered foci of tumor budding arise (Cytocheratin AE1-3 ×20). (c) Histological architecture encompassing cystically dilated glands, in part cribriform arranged (hematoxylin-eosin, ×50). (d) The pink eosinophilic material filling the more dilated glands; a clear space separates the glandular epithelium from the intraglandular material (hematoxylin-eosin, ×200).