Recurrence Timing and Risk Following Curative Resection of Colorectal Liver Metastases: Insights From a Hazard Function Analysis.

Introduction: There is no consensus on the optimal surveillance interval for patients undergoing resection of colorectal liver metastases (CRLM). We sought to assess the timing and intensity of recurrence following curative-intent resection of CRLM utilizing a recurrence-free survival (RFS) hazard function analysis.

Methods: Patients with CRLM who underwent curative-intent resection were identified from a multi-institutional database. The RFS hazard function was used to plot hazard rates and identify the peak of recurrence over time.

Results: Among 1804 patients, the median RFS was 19.9 months. In the analytic cohort, the RFS hazard curve peaked at 5.9 months (peak hazard rate: 0.054) and gradually declined, indicative of early recurrence. In subgroup analyses, patients with high and medium tumor burden scores (TBS) had RFS hazard peaks at 4.9 months (peak hazard rate: 0.060) and 5.8 months (peak hazard rate: 0.054), respectively. In contrast, patients with low TBS had a later peak at 7.5 months, with the lowest peak hazard rate of 0.047.

Conclusions: The recurrence peak for CRLM patients occurred approximately 6 months postsurgery, highlighting the need for intensified early postoperative surveillance. Patients with high TBS experienced earlier recurrence, underscoring the importance of close monitoring, particularly during the first 6 months after surgery.