[Pulmonary artery chemoembolization--from bench to bedside]

Locoregional approaches for inoperable lung metastases described in the literature are limited to isolated lung perfusion (ILP). A lot of experimental studies show feasibility and good oncological response with low toxicity. However, clinical applications are rare--probably due to the invasiveness of the procedure in a palliative aim. Recently chemoembolisation of the lung in a small-animal model was performed and compared to isolated lung perfusion and intravenous therapy. Using a simultaneous unilateral injection of degradable starch microspheres and carboplatin into the pulmonary artery, temporary reversible embolization at the capillary and arteriolar level has been achieved. Chemoembolization was superior to intravenous chemotherapy and had a response comparable to that of isolated lung perfusion in the solitary lung metastasis model. It was not associated with early toxicity and the long-term effect on lung parenchyma was similar to those of intravenous therapy and isolated lung perfusion. Since only a third of the normal intravenous cytostatic dose is used in chemoembolization, the general side effects are thus not a limiting factor. In the large-animal model, the new method can be performed interventionally via a pulmonary catheter without changing the circulation relevantly. After 6 months no chronic injury was seen. First clinical applications show that the procedure was well tolerated in patients with unresectable metastases.