Background: Treatment of peritoneal mesothelioma (PeM) poses significant challenges owing to its rare incidence, heterogeneity and limited clinical evidence. This manuscript describes results from a national consensus aimed at addressing management of PeM. Methods: An update of the 2018 Chicago Consensus Guidelines was conducted using a Modified Delphi technique, encompassing two rounds of voting. The levels of agreement for various pathway blocks were assessed. Results: Of 101 participants responding in the first round of Modified Delphi voting, 95 (94%) responded in the second round. Over 90% consensus was achieved in 5/6 and 6/6 pathway blocks in rounds I and II, respectively. Observation was recommended for benign neoplasms, with guidance for interventions in the presence of symptoms or concerning clinicopathologic features. For malignant pathology, management was outlined based on a multidisciplinary assessment of patient characteristics, disease histology, and predictive success of medical and surgical interventions. Additional emphasis was placed on multimodal therapy for Intermediate-Risk and appropriate High-Risk patients. A rapid review demonstrated limited availability of data and inconclusive findings regarding optimal systemic therapy timing. There was unanimous support for considering clinical trial enrollment. Conclusions: Given limited evidence, the consensus-driven pathway provides essential guidance regarding the management of PeM. To further direct clinical care, additional dedicated research to generate higher-quality evidence is needed.

The authors have declared no competing interest.

This study did not receive any funding

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