Goblet Cell Adenocarcinoma of the Appendix: Diagnosis, Prognosis and Nomenclature

Abstract

Goblet cell adenocarcinoma (GCA) is a new name for goblet cell carcinoid used by the fifth edition of the World Health Organization Classification of Tumors of the Digestive System published in 2019. This name change put an end to the years’ name confusion and led to the simplification and standardization of the diagnostic criteria and grading system for this unique epithelial neoplasm almost exclusively occurring in the appendix. This is extremely important because accurate diagnosis and grading are essential to patient management and prognostication. Under this new name, GCA is recognized to have low-grade and high-grade components with variable proportions. As such, the presence of the low-grade components is required for the diagnosis, but the proportion of the high-grade components dictates the prognosis. With regard to the nomenclature, GCA does not seem to be an ideal name for this tumor because goblet cells are apparently not the cell origin nor the unique cell population of the tumor. While the histogenesis remains ambiguous, the name “crypt cell carcinoma” would appear more appropriate for this tumor, as it would at least emphasize the crypt-like architecture and cellular composition of the tumor nests.