Combining imaging and laparoscopy for the staging of peritoneal metastases: A retrospective cohort pilot study

Abstract

BackgroundPeritoneal cancer (PC) staging work-up is challenging. Current gold standard is the Peritoneal Cancer Index (PCI) performed during laparotomy (LT). Accurate and less invasive alternatives, such as computed tomography (CT) or diagnostic laparoscopy (LS), are needed to avoid unnecessary laparotomies. Despite inherent limitations, these modalities have improved over time. Combination of both CT and laparoscopy for PCI evaluation might come close to laparotomy. ObjectiveTo analyze the accuracy, agreement and reliability of combined PCI (PCICT+LS) evaluation of CT (PCICT) and laparoscopy (PCILS) compared to laparotomy (PCILT) in patients eligible for cytoreductive surgery. MethodsA single-center retrospective pilot study of consecutive patients with PC irrespective of etiology, between February 2017 and May 2019. All included patients had sequential PCI staging with CT, laparoscopy and laparotomy. PCI was prospectively documented via a web-based form. Agreement and reliability were analyzed, using weighted-kappa and intraclass correlation respectively (ICC). ResultsOut of 220 patients, 25 had all three modalities of staging. Accuracy of PCICT+LS (76%) was highest between the 3 modalities in middle-PCI group (PCI 10 to 20), which was the group with the lowest accuracy (44–67%). Compared to laparotomy, reliability of combined CT + LS was the highest (ICC 0.91; 95% CI 0.81–0.96; p < 0.001). ConclusionsThe combination of CT with laparoscopy as combined PCI displayed the highest overall accuracy observed by group, as well as excellent reliability. CT is currently the preoperative reference imaging which may be enhanced by laparoscopy as a mandatory procedure selection of eligible candidates for CRS.