Background: Wedge resection or segmentectomy are the preferred treatments for pulmonary metastasis from colorectal cancer. However, local recurrence at the surgical margin is a problem with limited resections. This study attempted to identify predictive factors associated with local recurrences at the surgical margin after resection of pulmonary metastases.
Methods: A total of 96 lesions in 61 patients who had undergone a pulmonary wedge resection or segmentectomy for the treatment of pulmonary metastasis from colorectal cancer were investigated. Various clinical and pathologic factors were reviewed, and the risk of a local recurrence at the surgical margin was investigated.
Results: After pulmonary resection, 34 of the 61 patients (56%) experienced recurrences in their lungs. Local recurrences at the surgical margin were found in 17 patients (28%), even though 15 of these 17 cases had been histologically confirmed as completely resected cases. No clinical factors associated with local recurrence at the surgical margin were identified. Pathologically, lesions exhibiting 10 or more aerogenous spreads with floating cancer cell clusters around the main tumor (p = 0.02) and a malignant positive surgical margin (p = 0.04) had a significantly higher risk of local recurrence.
Conclusions: The present study indicated that local recurrence may occur even in cases with a pathologically negative surgical margin. In cases with pulmonary metastases from colorectal cancer, lesions with 10 or more aerogenous spreads with floating cancer cell clusters around the main lesion and a malignant positive surgical margin in the resected specimens have a significantly higher risk of local recurrence at the surgical margin than those without.