SP6.1.9 Colorectal Cancer and Synchronous Liver-limited Metastatic Disease: The final results of the CoSMIC Inception Cohort Study

Abstract

Abstract Aims Currently, evidence is inadequate to inform the selection of optimal treatment for patients with colorectal cancer and synchronous liver-limited hepatic metastases. Options include synchronous or staged surgery integrated with systemic chemotherapy. CoSMIC is the first inception cohort study to follow patients from point of presentation in order to identify factors influencing treatment and outcome. Methods Patients were identified at presentation to the regional liver metastases MDT at Manchester Royal Infirmary between April 2015-2018. Data were collected on demographics, intervention and outcome. The study was approved by Regional Ethics Committee (REC reference: 14/NW/1397). Results Of 125 patients recruited, 109 underwent surgery with 18 (17%) liver-first, 75 (69%) bowel-first and 16 (14%) undergoing synchronous resection. There were no differences in baseline demographics or co-morbidity. Eighty-eight completed the intended surgical pathway, with highest failure in liver-first patients where 39% did not proceed to subsequent bowel resection. Critical care occupancy between staged and synchronous resections (5.6 versus 5.2 days; P = 0.92), and inpatient stay (16.5 versus 16.8 days; P = 0.92) was not significant. There was no 30-day mortality. Cox regression analysis identified surgical sequence as a significant covariate (Х2= 31.3; P < 0.001). Survival was similar between surgical groups (Log-rank test; P = 0.87). Conclusions CoSMIC is the first prospective inception cohort study of colorectal cancer and synchronous liver-limited metastasis. The study population is small and from a single centre and thus could be influenced by recruitment and sample bias. However, the important novel finding is that there is no survival difference between treatment pathways.