Meta-Analysis of Survival Following Pulmonary Resection for Colorectal Cancer Metastases

Abstract

Background: Controversy exists regarding the optimal management of colorectal lung metastases (CRLM). This meta-analysis compared surgical (Surg) vs interventional (Chemotherapy and/or Radiotherapy) and observational non-surgical (NSurg) management of CRLM. Methods: A systematic review of the major databases including Medline, Embase, SCOPUS, and the Cochrane library was performed. Results: Ten studies including 2232 patients; 1551 (69%) comprised the Surg cohort, 521 (23%) the interventional NSurg group and 160 (7%), the observational NSurg group. A significantly higher overall survival was observed when Surg was compared to interventional NSurg at one-year (Surg 89%, 359/402 interventional NSurg 70%, 343/625, OR 2.76 (CI 2.10-3.63), P< 0.001), at three-years (Surg 59%, 857/1444 interventional NSurg 26%, 138/521, OR 2.61 (CI 1.65-4.15), P=0.002), at-five years (Surg 47%, 533/1144 interventional NSurg 23%, 45/196, OR 3.24 (CI 1.42-7.39), P=0.009) and at ten-years (Surg 27%, 306/1122 interventional NSurg 1%, 2/168, OR 15.64 (CI 1.87-130.76), P=0.031). In contrast however, Surg was associated with a greater overall survival than observational NSurg at only one-year (Surg 89%, 1009/1132 observational NSurg 67%, 93/138, OR 4.49 (CI 1.16-17.40), P=0.041) and was similar to observational NSurg at all other overall survival time points. Comparable survival was observed among Surg and overall NSurg cohorts at three- and five-year survival in articles published within the last three years. Conclusions: Recent evidence suggests comparable survival with Surg and NSurg modalities for CRLM, contrasting to early evidence where Surg had an improved survival. Significant selection bias.