Primary Tumor Resection in Patients With Metastatic Colorectal Cancer Is Associated With Reversal of Systemic Inflammation and Improved Survival

The effect of primary tumor resection on systemic inflammation and survival in metastatic colorectal cancer was evaluated. Reversal of an elevated neutrophil/lymphocyte ratio was associated with significantly improved overall survival and was more frequent in patients with greater primary tumor bulk. With additional validation, systemic inflammation and primary tumor bulk can help to refine patient selection for elective primary resection. Background: The true survival benefit of noncurative primary tumor resection in patients with de novo metastatic colorectal cancer (mCRC) remains uncertain. The present study examined the effect of primary tumor resection on systemic inflammation and survival in patients with mCRC. Materials and Methods: Consecutive patients with de novo mCRC who had undergone primary tumor resection were identified from a prospective database. Patients were excluded if they had undergone resection of metastases, had undergone delayed primary resection, or if blood samples survival (OS) was compared between patient groups according to the pre- and postprimary resection NLR. The associations between the reversal of an elevated NLR and primary tumor bulk or performance status were explored. Results: A total of 145 eligible patients were identified from the database, with a median age of 70 years. The baseline NLR was elevated (> 5) in 65 patients, 36 (55%) of whom had a low NLR after surgery. The reversal of an elevated NLR was associated with significantly improved OS (hazard ratio, 0.53; P = .017). A similar benefit was seen after excluding patients undergoing emergency primary resection. NLR reversal was more frequent in patients with larger primary tumors or good performance status. Conclusion: The present study is the first to demonstrate a relationship between the reversal of a systemic inflammatory response and the improved survival after primary resection in those with mCRC. A greater effect was seen in patients with large primary tumors. If validated, these observations could guide clinical decision-making in patients with mCRC at presentation. (C) 2015 Elsevier Inc. All rights reserved.