Survival after pulmonary metastasectomy in colorectal cancer patients: does a history of resected liver metastases worsen the prognosis? A literature review

Objective: To assess the impact of past liver metastases on the survival duration of patients who are undergoing surgery for lungmetastases. Methods: We conducted a review of literature published from 2007 to 2014. The studies were identified by searching PubMed,MEDLINE, and Embase and were supplemented by a manual search of the references listed by the retrieved studies. The followingsearch terms were used: lung metastasectomy, pulmonary metastasectomy, lung metastases, and lung metastasis. We selectedretrospective and prospective studies published from 2007 to 2014 on patients with lung metastases from colorectal cancer andwere undergoing surgery with curative intent. We excluded reviews, studies that focused on surgical techniques, patients who weretreated non-surgically, analyses of specific subgroups of patients, and those that did not report follow-up of the patientsundergoing surgery. Results: We identified 28 papers that assessed survival after lung metastases, 21 of which were mostly retrospective studies thatidentified previous liver metastases to explore their impact on patient survival. In more than half of the papers analyzed (63.2%),patients with a history of resected liver metastases had a lower survival rate than those who did not have such a history, and thedifference was statistically significant in eight of these studies. However, data were presented differently, and authors reportedmean survival time, survival rates, or hazard ratios. Conclusions: A history of liver metastases seems to be a negative prognostic factor, but the individual data need to undergo ameta-analysis.