Consensus guideline for the management of peritoneal metastases from neuroendocrine neoplasms.

Neuroendocrine neoplasms (NENs) with peritoneal metastases (PM) represent a complex clinical challenge because of low incidence and heterogeneous phenotypes. This commentary describes the results of a national consensus aimed at addressing clinical management of patients with NENs and PM. An update of the 2018 Chicago consensus guidelines was conducted with a modified Delphi technique, which encompassed two rounds of voting. The levels of agreement for various pathway blocks were assessed, and key systemic therapy concepts were summarized by content experts. Supporting evidence was evaluated via a rapid literature review. Overall, the level of evidence for the management of PM in this disease was universally low. In total, 107 participants responded in the first round, with 88 of 107 (82%) participating in the second round. Strong consensus (>90%) was achieved in five of seven (71%) and seven of seven (100%) blocks in rounds 1 and 2, respectively. A multidisciplinary approach including psychosocial and wellness assessments received a strong positive recommendation. Management of NENs with PM was organized according to disease grade and symptom profiles. In grade 1 and 2 well-differentiated NENs, cytoreductive surgery received strong support (>95%) after the management of functional syndromes (if present). For grade 3 well-differentiated NENs, systemic therapy is the primary recommendation, with surgical resection considered in select cases. Given the limited evidence, the consensus-driven clinical pathway offers vital clinical guidance for the management of NENs with PM. The need for high-quality evidence remains critical to the field.