Spinal reconstruction of the L5 vertebrae after tumor resection remains a challenge. Complex resection followed by circumferential fixation in the same setting, or in staged fashion, is often employed. The added operative time associated with this method potentially increases morbidity and mortality in an inherently high-risk procedure and anatomy in the lumbosacral area makes reconstruction more challenging. The authors describe a technique involving L5 vertebrectomy, placement of an expandable cage, and anterolateral L4-S1 screw fixation via a one-stage, one-position, anterolateral retroperitoneal approach. Two illustrative cases are presented along with the authors overall experience in L5 tumor operations. We believe that this is a feasible reconstructive option after tumor resection in lower lumbar metastatic spine disease. The approach may be also utilized in combined anteroposterior (two-stage) procedures in primary malignant tumors or oligometastatic disease. J. Surg. Oncol. 2011; 104:552–558. © 2011 Wiley-Liss, Inc.