[Surgical management of pulmonary metastases]

Because lung metastasis from a solid malignant tumor is a distant and hematogenous metastasis, its prognosis is generally dismal. Therefore, the indications of local therapy such as surgical resections of lung metastasis remain very controversial. However, in some cases, the metastasis of tumor cells from the primary site can be confined to the lungs before systemic and disseminated disease. Surgical resection could be a curative treatment at this stage of lung metastasis. A smaller number of metastases, long disease-free survival time, and no lymph node metastasis are the predictive factors for good prognosis after resection of lung metastasis. However, there have been no criteria for the indications of lung metastasectomies. Indications and outcomes of surgical resection for lung metastasis depend on each primary malignancies. Wedge resection of the lung is thought to be an appropriate procedure for the resection of metastatic lung tumors. Video assisted thoracoscopic resection is now widely used, however, controversy persists about whether this technique is appropriate approach for the patients undergoing metastasectomy with curative intent because the lack of palpation may be a cause of missing small metastatic lung tumors despite the advent of high resolution CT. There is no randomized trial assessing whether there is any difference in survival after metastasectomy with versus without manual lung palpation. Recent progress of chemotherapy, such as FOLFOX for colorectal cancer, could change the indications and outcome of surgical resection of metastatic lung tumors. In addition, newly developed radiofrequency ablation came to be performed as local therapy in some centers. We should decide the timing of resection considering the schedule of chemotherapy, so close corporation of surgeons and physicians is essential for managing metastatic lung tumors.