Comprehensive data of 3525 patients newly diagnosed with colorectal liver metastasis between 2013 and 2014: 2nd report of a nationwide survey in Japan

Background To collect large‐scale data for further research to improve treatment outcomes in patients with colorectal liver metastasis (CRLM), the Joint Committee for Nationwide Survey on CRLM was established by the Japanese Society for Cancer of the Colon and Rectum and the Japanese society of Hepato‐Biliary‐Pancreatic Surgery. The joint committee was initiated to collect data since 2014 and has already reported data including the prognostic data of 3820 patients newly diagnosed with CRLM between 2005 and 2007. Methods The data of patients newly diagnosed with CRLM after 2013 are continuously being registered prospectively, and herein, we report the data of the patients newly diagnosed with CRLM in 2013 and 2014. Results The data of 3839 patients newly diagnosed with CRLM in 2013 and 2014 were registered from 156 departments (75%) of 152 institutions among 209 departments (from 201 institutions) that agreed to participate in this database system at its initiation. Finally, 3525 patients were enrolled in this study after a quality management process conducted by the joint committee. We report the comprehensive data obtained from 3525 patients, including clinicopathological findings, treatment strategies, and implementation status of chemotherapy. Conclusion The joint committee will provide these raw data while updating prognostic data to researchers who will conduct meaningful studies that meet the aim of the joint committee. Highlight On behalf of the Joint Committee for Nationwide Survey on Colorectal Liver Metastasis (CRLM), established in Japan to collect big data for further research in patients with CRLM, Sakamoto and colleagues present the second report with comprehensive data obtained from 3525 patients newly diagnosed with CRLM between 2013 and 2014.