Diseases of the Colon & Rectum | 2021
Implications of Pathological Findings in Cytoreductive Surgery Specimens on Treatment of Colorectal Peritoneal Metastases- Results of a Prospective Multi-Centric Study.
Abstract
BACKGROUND\nA surgical PCI of >20 is often used to exclude patients from cytoreductive surgery for colorectal peritoneal metastases. The pathological PCI in these patients may be <20.\n\n\nOBJECTIVES\nTo compare the pathological and surgical findings and look at potential pathological prognostic factors.\n\n\nDESIGN\nThis is a prospective observational study including patients undergoing cytoreductive surgery.\n\n\nSETTINGS\nThe study was carried out at three peritoneal surface malignancy centres, 1 in France and 2 in India.\n\n\nPATIENTS\nOne-hundred patients were included from 1st July 2018 to 30th June 2019.\n\n\nINTERVENTIONS\nThere was no therapeutic intervention.\n\n\nMAIN OUTCOME MEASURES\nThe pathological PCI, peritoneal disease distribution, pathological response to chemotherapy, factors affecting them and their relation with surgical findings and potential prognostic value was explored.\n\n\nRESULTS\nNinety percent had colonic primaries. Fifty-one% had left sided tumors. The median surgical PCI was 4[0-35]. Upper regions were involved in 32% and small bowel regions 26% and their involvement increased with a higher PCI (p<0.001). The median pathological PCI was 2[0-27] and was less than the surgical PCI in 57%. A pathological complete response was obtained in 25%. Patients with pathological complete response received more anti-EGFR therapy (p=0.008) and more FOLFOX and FOLFIRINOX (p<0.001). In 7 patients with a surgical PCI of >20, pathological PCI was less than 20 in 4 patients. Disease in the primary tumor/anastomotic site was found in nearly 80%.\n\n\nLIMITATIONS\nSurvival outcomes are not available.\n\n\nCONCLUSIONS\nSurgical PCI of >20 should not be the sole factor to exclude patients from surgery especially in responders to systemic therapies. The pathological PCI, pathological response to systemic chemotherapy and disease distribution in the peritoneal cavity should be meticulously documented. Correlation with survival will define their future prognostic value. The primary anastomotic site is a common site for peritoneal disease and should be carefully evaluated in all patients. See Video Abstract at http://links.lww.com/DCR/B490.