Survival outcome following surgical versus non-surgical treatment of colorectal lung metastasis-a retrospective cohort study.

Purpose: The optimal management of colorectal lung metastases (CRLM) is still controversial. The aim of this study was to compare surgical and non-surgical treatment for CRLM regarding the prognostic outcome.

Methods: This retrospective single-center cohort study included 418 patients, who were treated from January 2000 to December 2018 at a German University Hospital due to their colorectal carcinoma and had synchronous or metachronous lung metastases. Patients were stratified according the treatment of the CRLM into two groups: surgical resection of CRLM versus no surgical resection of CRLM. The survival from the time of diagnosis of lung metastasis was compared between the groups.

Results: Two- and 5-year overall survival (OS) from the time of diagnosis of lung metastasis was 78.2% and 54.6%, respectively, in our cohort. Patients undergoing pulmonary metastasectomy showed a significantly better 2- and 5-year survival compared to patients with non-surgical treatment (2-year OS: 98.1% vs. 67.9%; 5-year OS: 81.2% vs. 28.8%; p < 0.001). Multivariate Cox regression revealed the surgical treatment (HR 4.51 (95% CI = 2.33-8.75, p < 0.001) and the absence of other metastases (HR 1.79 (95% CI = 1.05-3.04), p = 0.032) as independent prognostic factors in patients with CRLM.

Conclusion: Our data suggest that patients with CRLM, who qualify for surgery, benefit from surgical treatment. Randomized controlled trials are needed to confirm our findings.

Clinical Trial Registry Number: The work has been retrospectively registrated at the German Clinical Trial Registry (DRKS00032938).