Factors affecting survival in patients with lung metastases from colorectal cancer. A short meta-analysis

Liver and pulmonary metastases (PMs) are relatively common in patients with colorectal cancer. The majority of metastases are suitable for surgical resection, and the effectiveness of metastasectomy is usually assessed based on overall survival (OS). Metastasectomy provides a mean 5-year OS rate of approximately 50%, but the results are better in patients with liver metastases compared to those with PMs. Unfortunately, the presence of bilateral or multiple PMs represents a relative contraindication to surgical metastasectomy. Unresectable PMs can be safely treated with percutaneous radiofrequency ablation or radiotherapy, but the reported results vary widely. Several clinical prognostic factors affecting OS after metastasectomy have been reported, such as number of PMs, hilar or mediastinal lymph node involvement, disease-free interval, age and gender, resection margins, size of the metastases, neoadjuvant chemotherapy administration, and histological type of the primary cancer. The accurate evaluation of all clinical prognostic factors, circulating and immunohistochemical markers, and the study of gene mutational status will lead to a more accurate selection of patients scheduled to metastasectomy, with the aim of improving outcome.