RT Journal Article T1 Defining stage in mucinous tumours of the appendix with peritoneal dissemination: the importance of grading terminology: systematic review A1 Martín Román, L. A1 Lozano, Pablo A1 Vásquez, W. A1 Palencia, N. A1 Gómez, Y. A1 Fernández Aceñero, María Jesús A1 González Bayón, Luis Andrés AB BackgroundMucinous appendiceal neoplasms with peritoneal dissemination (PD) show a wide spectrum of clinical behaviour. Histological grade has been correlated with prognosis, but no universally accepted histological grading has been established. The aim of this systematic review was to provide historical insight to understand current grading classifications, basic histopathological features of each category, and to define which classification correlates best with prognosis.MethodsMEDLINE and the Cochrane Library were searched for studies that reported survival across different pathological grades in patients with mucinous neoplasm of the appendix with PD treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. PRISMA guidelines were followed.ResultsThirty-eight studies were included. Ronnett’s classification was the most common (9 studies). Classifications proposed by the Peritoneal Surface Oncology Group International (PSOGI) (6 studies) and the seventh or eighth edition of the AJCC (7 studies) are gaining in popularity. Nine studies supported a two-tier, 12 a three-tier, and two a four-tier classification system. Three studies demonstrated that acellular mucin had a better prognosis than low-grade pseudomyxoma peritonei in the PSOGI classification or M1bG1 in the eighth edition of the AJCC classification. Four studies demonstrated that the presence of signet ring cells was associated with a worse outcome than high-grade pseudomyxoma peritonei in the PSOGI classification and M1bG2 in the eighth edition of the AJCC.ConclusionThere is a great need for a common language in describing mucinous neoplasms of the appendix with PD. Evolution in terminology as a result of pathological insight turns the four-tiered PSOGI classification system into a coherent classification option. PB Oxford University Press YR 2021 FD 2021-08-05 LK https://hdl.handle.net/20.500.14352/116123 UL https://hdl.handle.net/20.500.14352/116123 LA eng NO L Martín-Román, P Lozano, W Vásquez, N Palencia, Y Gómez, M J Fernández-Aceñero, L González-Bayón, Defining stage in mucinous tumours of the appendix with peritoneal dissemination: the importance of grading terminology: systematic review, BJS Open, Volume 5, Issue 4, July 2021, zrab059, https://doi.org/10.1093/bjsopen/zrab059 DS Docta Complutense RD 21 abr 2025