Surgical treatment for pulmonary metastases

As the lungs are a filter for the entire circulation, they are a common site for metastatic disease. Although never proven by a prospective randomized trial, surgical resection is a widely accepted treatment for pulmonary metastases on the condition that a complete resection can be obtained. However, many patients will develop recurrent disease in the thorax despite the use of systemic chemotherapy, dosage of which is limited due to systemic toxicity. As isolated limb and liver perfusion, isolated lung perfusion is an attractive and promising surgical technique for the delivery of high-dose chemotherapy with minimal systemic toxicity. The use of biological response modifiers, like tumour necrosis factor, is also feasible. Isolated lung perfusion has proven to be highly effective in rat models of pulmonary metastases with a clear survival advantage. Lung levels are significantly higher after isolated lung perfusion compared to intravenous therapy without systemic exposure. Preliminary human studies have shown that isolated lung perfusion is technically feasible with low morbidity and without compromising the patient's pulmonary function. Further clinical research is necessary to determine its effect on pulmonary metastases in man, especially in case of unresectable disease or as adjuvant therapy after surgical resection.