Evaluation of prognostic factors in patients undergoing surgery for colorectal cancer lung metastases

Lungs are the second most frequent site of colorectal cancer metastases. Complete resection of isolated lung metastases is recommended in the current guidelines because of the high long-term survival rate and low morbidity-mortality. The aim of this study is to determine prognostic factors for lung metastasectomy in order to better select patients who will benefit from surgical resection.

This single-center retrospective study is based on the medical data of patients operated for resection of colorectal lung metastases between 2004 and 2023.

A total of 109 patients were selected, and four had to be excluded. The univariate analysis revealed factors influencing the survival: primary cancers that were metastatic at diagnosis, high preoperative CEA rate, the number and size of metastases, hilar lymph node involvement, invasion of the resection margins and poorly differentiated histological grade. A multivariate analysis including only the pre-operative factors was performed: CEA (p < 0.001), the size (p = 0.003) and number (p = 0.038) of metastases and the metastatic stage of the primary cancer at diagnosis (p = 0.052).

The 5-year survival rate in this study is 55%. Survival can be evaluated by four preoperative factors: CEA rate, size and number of metastases and metastatic status of the primary cancer. These factors can be combined to form a survival score, each factor being worth one point. Patients with a score of 0 have a 5-year survival of around 90%, while patients with a score of 3 have a 5-year survival of around 10%. This score could be used to select patients eligible for surgery.