The INDEPSO-ISPSM Consensus on Peritoneal Malignancies-Mucinous Appendiceal Neoplasms and Pseudomyxoma Peritonei

Vivekanand Sharma1, Somashekhar Sp2, Rohit Kumar2

  • 1Dept of Colorectal Surgery, East Suffolk and North Essex NHS Foundation, Ipswich, UK.

PubMed

Insights

This consensus exercise provides recommendations for managing rare mucinous appendiceal neoplasms (MANs) and pseudomyxoma peritonei (PMP). Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is recommended for specific advanced MANs and PMP cases.

Area of Science:

  • Gastroenterology
  • Surgical Oncology
  • Oncology

Background:

  • Mucinous appendiceal neoplasms (MANs) and pseudomyxoma peritonei (PMP) present unique and rare therapeutic challenges.
  • Existing international guidelines may not fully address all clinical scenarios for these conditions.

Purpose of the Study:

  • To establish expert consensus on clinically pertinent issues in MANs and PMP management.
  • To reinforce and update recommendations from existing international guidelines.

Main Methods:

  • A modified Delphi method involving two rounds of voting by 45 international panelists.
  • 42 questions covering seven key issues in MANs and PMP management were addressed.
  • Consensus was defined as >70% agreement, with strong consensus >90%.

Main Results:

  • Consensus was achieved on 36 out of 42 questions (88%).
  • CRS-HIPEC was recommended for perforated (pT4) high-grade MANs, pT4 poorly differentiated/signet ring cell tumors without peritoneal disease, and all overt peritoneal disease.
  • HIPEC in addition to CRS was recommended for PMP; consensus was not reached for pT3 HAMNs or intraoperatively detected MANs with peritoneal spread.

Conclusions:

  • Expert consensus supports CRS-HIPEC for specific advanced MANs and PMP, aligning with but also refining international guidelines.
  • The consensus provides guidance on debatable interventions like fertility-sparing surgery and CRS for extraperitoneal disease.
  • A more stringent approach to prophylactic CRS and HIPEC in post-appendicectomy scenarios was recommended.