Sessile Serrated Polyp/Adenoma of the Appendix
Differential Diagnosis
Appendiceal hyperplastic polyp should be distinguished from appendiceal sessile serrated adenoma using the same features as in the colorectum
Appendiceal Hyperplastic Polyp / Mucosal Hyperplasia | Appendiceal Sessile Serrated Polyp/Adenoma |
Bases of crypts straight, regular, frequently pointed | Crypts dilated, branched, occasional horizontal bases |
Serrations restricted to upper part of glands | Serrations may involve base |
Proliferative zone reliably restricted to base | Proliferative zone frequently irregularly displaced upwards from the base |
Both are benign if completely excised and completely sectioned
Appendiceal traditional serrated adenoma should be distinguished from appendiceal sessile serrated adenoma using the same features as in the colorectum
Appendiceal Traditional Serrated Adenoma | Appendiceal Sessile Serrated Polyp/Adenoma |
Cytologic dysplasia throughout | Cytologic dysplasia, if present, is a focal lesion |
Typically complex architecture | Minor architectural disturbances but overall, crypts are vertically arranged and not complex |
Both are benign if completely excised and completely sectioned