Short disease-free interval is a significant risk factor for intrapulmonary recurrence after resection of pulmonary metastases in colorectal cancer.

OBJECTIVE: Surgical resection has been the first choice of treatment for resectable pulmonary metastases from colorectal cancer. However, early intrapulmonary recurrence is often observed and appropriate assessment of prognostic factors is controversial. The aim of this study was to define the factors affecting survival and intrapulmonary recurrence after surgical treatment of metastatic pulmonary tumours from colorectal cancer.

METHOD: A retrospective analysis was performed of 56 consecutive patients who underwent pulmonary resection for colorectal metastases with a focus on prognostic factors and risk factors for intrapulmonary recurrence.

RESULTS: The overall 5-year survival rate was 48.2%. In a univariate analysis, a short disease-free interval (DFI), multiple pulmonary metastases and abnormal prethoracotomy carcinoembryonic antigen (CEA) levels were poor prognostic factors. In a multivariate analysis, a short DFI and abnormal prethoracotomy CEA levels were independent prognostic factors. Twenty-two (39.3%) of the 56 patients had recurrences in the remnant lung after resection for pulmonary metastases, and 8 (36.4%) of these 22 patients underwent repeated pulmonary resections. The median DFI between first and second lung metastasis was 13 months. Univariate analyses revealed that multiple and bilateral lung metastases were risk factors for intrapulmonary recurrence. There was also a strong correlation between the DFI for intrapulmonary recurrence after the first pulmonary resection and the DFI for first pulmonary metastases.

CONCLUSIONS: A short DFI was a risk factor for early tumour recurrence after resection for pulmonary metastases. The DFI might reflect oncological characteristics such as the tumour doubling time in colorectal cancer.