Is finger palpation at operation indispensable for pulmonary metastasectomy in colorectal cancer?

Background: The use of thoracoscopic techniques for pulmonary metastasectomy is controversial because small metastatic foci might be missed without thorough finger palpation of the lung.

Methods: We retrospectively examined preoperative findings of helical computed tomography and pathologic findings of pulmonary nodules obtained by open thoracotomy, including median sternotomy or thoracoscopy, in patients thought to have pulmonary metastasis from colorectal cancer.

Results: We performed 122 pulmonary metastasectomies (43 thoracotomies and 79 thoracoscopies) in 102 patients from 1999 to 2005. Repeat metastasectomies were excluded. Preoperative evaluation revealed 219 pulmonary nodules suspicious for pulmonary metastasis, and 250 nodules were resected; however, pathologic examination revealed that 47 (18.8%) of 250 nodules were not metastases. When the diameters of the pulmonary nodules were small, the rates of metastasis were also significantly lower. Finally, 4 thoracotomy (9.3%) and 5 thoracoscopy patients (6.3%) were found to have additional pulmonary metastases at operation. Recurrent pulmonary metastases were found at the ipsilateral side of the metastasectomy in 27 (34.2%) of 79 thoracoscopies and 27 (62.8%) of 43 open thoracotomies (p = 0.0023) within 2 years after the pulmonary surgery. These metastatic foci might have been missed at the time of pulmonary metastasectomy.

Conclusions: The ability to detect pulmonary metastases in patients with colorectal cancer is limited by preoperative evaluation with computed tomography and surgical techniques, including open thoracotomy with bimanual palpation. Pulmonary metastasectomy by open thoracotomy or thoracoscopy may be a suboptimal intervention to remove metastatic foci in the lungs.