Consensus Guideline for the Management of Malignant Gastrointestinal Obstruction in Patients with Peritoneal Surface Malignancies.

Background: Malignant gastrointestinal obstruction (MGIO), a frequent complication of peritoneal surface malignancies (PSM), often portends a poor prognosis. The lack of high-quality evidence on optimal management strategies necessitated a national consensus to address this clinical problem.

Methods: A clinical management pathway was designed through a Delphi consensus process with national experts in peritoneal disease.

Consensus Guideline for the Management of Patients with Appendiceal Tumors, Part 2: Appendiceal Tumors with Peritoneal Involvement.

Background: Appendiceal tumors comprise a heterogeneous group of tumors that frequently disseminate to the peritoneum. Management of appendiceal tumors is lacking high quality data given their rarity and heterogeneity. In general, appendiceal tumor treatment is extrapolated in part from colorectal cancer or pooled studies, without definitive evidence of disease-specific benefit.

Consensus Guideline for the Management of Peritoneal Mesothelioma.

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.

Consensus Guideline for the Management of Gastric Cancer with Synchronous Peritoneal Metastases.

Background: Gastric cancer with synchronous peritoneal metastases (GCPM) is a debilitating disease with limited treatment options. This manuscript describes an update of the 2018 Chicago Consensus Guidelines addressing the management of GCPM in line with most recent evidence.

Methods: A clinical management pathway was updated through two rounds of a Delphi Consensus to assess agreement levels with pathway blocks.

Consensus Guideline for the Management of Patients with Appendiceal Tumors, Part 1: Appendiceal Tumors Without Peritoneal Involvement.

Background: Appendiceal tumors comprise a heterogeneous group of tumors that may be localized or disseminate throughout the peritoneum. Limited high quality clinical data exist and many practices have been extrapolated from colorectal cancer without validation in appendiceal cohorts. There are many controversies regarding the treatment of appendiceal tumors, and practices vary widely between centers and care settings.

Consensus Guideline for the Management of Colorectal Cancer with Peritoneal Metastases.

Background: The peritoneum is a common site of metastases from colorectal cancer (CRC), yet controversy exists regarding optimal treatment strategies. These guidelines describe the results of a national consensus addressing the management of CRC with peritoneal metastases (CRC-PM).

Methods: An update of the 2018 Chicago Consensus Guidelines was conducted using a modified Delphi technique.

Consensus Guideline for the Management of Peritoneal Metastases from Neuroendocrine Neoplasms.

Background: Neuroendocrine neoplasms (NEN) with peritoneal metastases (PM) represent a complex clinical challenge due to low incidence and heterogeneous phenotypes. This manuscript describes the results of a national consensus aimed at addressing clinical management of patients with NEN-PM.

Methods: An update of the 2018 Chicago consensus guidelines was conducted using a modified Delphi technique, encompassing two rounds of voting.

Peritonectomy procedures for peritoneal surface malignancies: PSOGI-ESGO-ISSPP Lyon consensus.

Background: The nomenclature and execution of peritonectomy procedures for peritoneal surface malignancies significantly vary between surgeons and centres. The aim of this consensus was to reach uniform nomenclature for peritonectomy procedures, to define subregions of each peritonectomy procedure, and to define boundaries of each subregion.

Methods: The modified Delphi technique was employed.

Peritonectomy to enhance adequate cytoreductive surgery in peritoneal surface malignancy: review of nomenclature and boundaries.

Background: Cytoreductive surgery is increasingly performed worldwide for a variety of primary and secondary peritoneal surface malignancies. Significant heterogeneity exists regarding the extent of peritonectomy performed in each abdominal region and the terminology used to describe the surgical procedure. The aims of this review were to summarize the literature and identify gaps where consensus is needed.

Consensus guideline for the management of peritoneal mesothelioma.

The treatment of peritoneal mesothelioma (PeM) poses significant challenges because of its rare incidence, heterogeneity, and limited clinical evidence. This commentary describes results from a national consensus aimed at addressing the management of PeM. An update of the 2018 Chicago consensus guidelines was conducted with a modified Delphi technique, which encompassed two rounds of voting.

Consensus guideline for the management of patients with appendiceal tumors, part 2: Appendiceal tumors with peritoneal involvement.

Background: Appendiceal tumors comprise a heterogeneous group of tumors that frequently disseminate to the peritoneum. Management of appendiceal tumors is lacking high-quality data given their rarity and heterogeneity. In general, appendiceal tumor treatment is extrapolated in part from colorectal cancer or pooled studies, without definitive evidence of disease-specific benefit.

Consensus guideline for the management of colorectal cancer with peritoneal metastases.

The peritoneum is a common site of metastases from colorectal cancer (CRC), yet controversy exists regarding optimal treatment strategies. These guidelines describe the results of a national consensus addressing the management of CRC with peritoneal metastases (CRC-PM). An update of the 2018 Chicago consensus guidelines was conducted with a modified Delphi technique.

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.

Consensus guideline for the management of patients with appendiceal tumors, part 1: Appendiceal tumors without peritoneal involvement.

Background: Appendiceal tumors comprise a heterogeneous group of tumors that may be localized or disseminated throughout the peritoneum. Limited high-quality clinical data exist, and many practices have been extrapolated from colorectal cancer without validation in appendiceal cohorts. There are many controversies regarding the treatment of appendiceal tumors, and practices vary widely between centers and care settings.

Consensus guideline for the management of gastric cancer with synchronous peritoneal metastases.

Background: Gastric cancer with synchronous peritoneal metastases is a debilitating disease with limited treatment options. This article describes an update of the 2018 Chicago Consensus guidelines addressing the management of gastric cancer with synchronous peritoneal metastases in line with the most recent evidence.

Methods: A clinical management pathway was updated through two rounds of a Delphi consensus to assess agreement levels with pathway blocks.

A Feasibility Study of Mass-Based Response Drug Screening to Guide Personalized Hyperthermic Intraperitoneal Chemotherapy for Appendiceal and Colorectal Adenocarcinoma with Peritoneal Metastasis.

Background: Current treatment of metastatic peritoneal surface malignancies (PSM) arising from colorectal cancer (CRC) and appendiceal cancer involves cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) [Elias (J Clin Oncol 28:63-68, 2010), McMullen (Oncotarget 8: 43481-43490, 2017), Lemoine (Int J Hyperthermia 33:582-592, 2017)]. There have been several intraperitoneal (IP) trials of appendix and colon cancer with conflicting results and insufficient evidence regarding both HIPEC efficacy and optimal HIPEC regimens [Quenet (Lancet Oncology 22:256-266, 2021), Arjona-Sánchez (JAMA Surgery 158:683, 2023), Verwaal (Ann Surg Oncol 12:65-71, 2004), Benzaquen (Can J Surg 64: E111-E118, 2021), Turaga (Ann Surg Oncol 21: 1501-1505, 2014), Nash (J Clin Oncol 41: 160, 2023)]. Given the heterogeneity of prior data and the variability in patient responses to different HIPEC regimens, further research is needed to optimize and personalize treatment.

Systemic chemotherapy in patients with unresectable pseudomyxoma peritonei from low-grade appendiceal mucinous neoplasms: a case series.

Background: Patients with unresectbale low-grade appendiceal mucinous neoplasms (LAMNs) with pseudomyxoma peritonei (PMP) have very few viable treatment options. While aggressive appendiceal pathologies benefit from systemic chemotherapy, it is not clear whether LAMNs do. This is partly due to the rarity of the disease and the heterogeneity in its classification and description in the literature.

Sorafenib or anthracycline-based chemotherapy for progressive desmoid tumors.

Background: Desmoid tumors can cause morbidity due to local invasion, potentially being fatal when fast growth compromises vital structures. In this context, a timely treatment response is required. This study aims to compare the activity of sorafenib and anthracycline-containing regimens during the first year of treatment.

When Benchmarks Fail Us: A Case Study in Cytoreductive Surgery.

Introduction: Relative Value Units (RVUs) are utilized to measure physician work effort and create national benchmarks. Physicians are often measured against national benchmarks to determine compensation. Using a case study in cytoreductive surgery, we explored variability in coding that can impact national benchmarks.

Mutational Features and Tumor Microenvironment Alterations in High-Grade Appendiceal Cancers Treated With Iterative Hyperthermic Intraperitoneal Chemotherapy.

Purpose: High-grade appendiceal adenocarcinomas (HGAA) with peritoneal metastases (PMs) are associated with poor survival. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a novel treatment approach for unresectable HGAA-PM. However, its influence on immunogenomic profiles has not yet been fully explored.

Multi-Institutional Study Evaluating the Role of Circulating Tumor DNA in the Management of Appendiceal Cancers.

Purpose: Conventional surveillance methods are poorly sensitive for monitoring appendiceal cancers (AC). This study investigated the utility of circulating tumor DNA (ctDNA) in evaluating systemic therapy response and recurrence after surgery for AC.

Methods: Patients from two specialized centers who underwent tumor-informed ctDNA testing (Signatera) were evaluated to determine the association between systemic therapy and ctDNA detection.

Implementation of a high-resolution, high-contrast magnetic resonance imaging protocol with extended delayed phases for peritoneal mesothelioma.

Background: Imaging of peritoneal malignancies using conventional cross-sectional imaging is challenging, but accurate assessment of peritoneal disease burden could guide better selection for definitive surgery. Here we demonstrate feasibility of high-resolution, high-contrast magnetic resonance imaging (MRI) of peritoneal mesothelioma and explore optimal timing for delayed post-contrast imaging.

Methods: Prospective data from inpatients with malignant peritoneal mesothelioma (MPM), imaged with a novel MRI protocol, were analyzed.