Isolated lung perfusion and related techniques for the treatment of pulmonary metastases.

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 because of systemic toxicity. Similar to the basic principles of 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. Other related methods of delivering high-dose locoregional chemotherapy include embolic trapping (chemo-embolisation) and pulmonary artery infusion without control of the venous effluent. Isolated lung perfusion has proven to be highly effective in experimental models of pulmonary metastases with a clear survival advantage. Lung levels of cytostatic drugs are significantly higher after isolated lung perfusion compared to intravenous therapy without systemic exposure. Phase I human studies have shown that isolated lung perfusion is technically feasible with low morbidity and without compromising the patient's pulmonary function. Further clinical studies are necessary to determine its definitive effect on local recurrence, long-term toxicity, pulmonary function and survival.