Early recurrence predicts survival in patients with 10 or more bilobar colorectal liver metastases: A LASSO regression-based nomogram model.

INTRODUCTION: Parenchymal-sparing one-stage hepatectomy (POSH) has expanded surgical eligibility for patients with high-burden (≥10) colorectal liver metastases (CLM). Early recurrence (ER), defined as recurrence within 6 months, remains a challenge, and its prognostic significance and preoperative predictability in this population are poorly defined. This study aimed to evaluate the long-term impact of ER, to develop and validate a preoperative predictive model, and to assess the feasibility of repeat curative treatment according to recurrence patterns. METHODS: Consecutive patients undergoing curative-intent POSH for ≥10 bilobar CLM at a single institution (2014-2023) were retrospectively analyzed. A LASSO-penalized preoperative nomogram was developed and internally validated (bootstrap), with additional external, temporal validation in an independent 2023-2025 cohort. Overall Survival (OS) and repeat hepatectomy feasibility were assessed. RESULTS: Among 103 patients, ER occurred in 51.5%. ER patients had significantly shorter median OS than non-ER patients (30.6 vs 53.4 months; p = 0.011), with ER remaining independently associated with OS on multivariate analysis (HR 2.18; p = 0.016). The preoperative nomogram demonstrated strong discrimination (C-index: 0.831), preserved at internal (C-index: 0.786) and temporal validation (C-index: 0.733). ER patients undergoing repeat curative treatment achieved 3-year OS comparable to late recurrence patients (72.0% vs 79.9%), whereas those who did not had dismal outcomes (17.1%; p < 0.001). CONCLUSIONS: In high-burden CLM, ER represents a biological marker of poor prognosis. The validated nomogram enables preoperative identification of high-risk patients, supporting intensified postoperative surveillance strategies. ER prompt detection is critical to facilitate repeat curative interventions, which remain the only pathway to prolonged survival.