Pseudomyxoma peritonei most commonly arises from which primary site?
- A Appendiceal mucinous neoplasm (low-grade appendiceal mucinous neoplasm, LAMN) ✓
- B Ovarian mucinous cystadenoma
- C Colorectal adenocarcinoma with mucin secretion
- D Pancreatic mucinous cystic neoplasm
Correct answer: A. Appendiceal mucinous neoplasm (low-grade appendiceal mucinous neoplasm, LAMN)
Explanation
Pseudomyxoma peritonei (PMP) — diffuse intraperitoneal accumulation of mucinous tumour — arises in >90% of cases from a low-grade appendiceal mucinous neoplasm (LAMN), often presenting as a ruptured appendiceal mucocele. Ovarian mucinous tumours in PMP are almost always secondary deposits from the appendix, not the primary source. Molecular studies (CK7/CK20 profiles and MUC patterns) confirm the appendiceal origin. Treatment is cytoreductive surgery + hyperthermic intraperitoneal chemotherapy (HIPEC).
Reference: Shaw's Textbook of Gynaecology, 17th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.