The dilemma of the disappearing colorectal liver metastases: defining international trends in management.

OBJECTIVE:This survey sought to appraise the degree of consistency in the management of disappeared colorectal liver metastases (dCRLM) among liver surgeons in different countries. BACKGROUND:Colorectal liver metastases (CRLM) account for half of the deaths secondary to colorectal cancer. Due to the high utilization of chemotherapy before surgery, some or all CRLM can disappear (dCRLM) but management of dCRLMs remains unclear. METHODS:Seven simulated scenarios of dCRLM were presented to experienced liver surgeons using an online platform. Treatment decisions were submitted and analysed using the multi-rater kappa method. The effect of the experience, complexity of scenarios, and location and number of dCRLM on treatment decision were analysed. RESULTS:Sixty-seven liver surgeons from 25 countries completed the survey. There was no agreement about the therapeutic strategies of dCRLM in all scenarios (kappa 0.12, IQR 0.20-0.32). In scenarios with lower difficulty scores, surgeons tended to offer surgical resection for dCRLM alongside the visible CRLM (vCRLM), however, with poor agreement (kappa 0.32, IQR 0.19-0.51). No agreement was seen for clinical scenario in which all CRLM lesions disappeared (kappa 0.20). CONCLUSION:There are clear inconsistencies in the management decisions of dCRLM. Better evidence is required to define optimal management strategies.