Appendiceal mucinous neoplasm
The clinical course of appendiceal mucinous neoplasms has a wide range that depends on the specific diagnosis, stage, and histologic grade of the neoplasm. Appendiceal mucinous neoplasms include serrated polyps, hyperplastic polyps, low-grade appendiceal mucinous neoplasms (LAMNs), high-grade appendiceal mucinous neoplasms (HAMNs), and mucinous adenocarcinomas of the appendix. Low-grade tumors confined to the appendix can be slowly progressing with good prognosis, whereas high-grade adenocarcinomas can be aggressive with high rates of reoccurrence.
Prognosis also depends on whether there is progression to pseudomyxoma peritonei, characterized by peritoneal spread of mucin. As the appendiceal mucinous neoplasm proliferates, mucin accumulates and can involve the peritoneal cavity in cases of mucin dissecting through the wall, or mural perforation. Complication by pseudomyxoma peritonei indicates advanced-stage disease, and prognosis is less favorable. Around 20% of patients with an appendiceal mucinous neoplasm develop pseudomyxoma peritonei.
D12.1 – Benign neoplasm of appendix
450896006 – Low grade appendiceal mucinous neoplasm
Differential Diagnosis & Pitfalls