Hypoxic Stop-Flow Perfusion with Mitomycin-C in the Treatment of Multifocal Liver Metastases. Usefulness of a Vascular Arterial Stent to Prevent Iatrogenic Lesions of the Hepatic Arterial Wall

: 13 patients affected by multifocal and/or large liver metastases from various solid tumors have been treated with stop-flow liver perfusion, to evaluate the safety and feasibility of hypoxic loco-regional infusion with Mitomycin C. The treatment was based on the hypoxic effect due to stop-flow, potentiating the cytotoxic activity of Mitomycin C, combined with the ischemic damage caused by the embolization of the vascular supply to the tumor. The schedule consisted in blocking arterial flow by an angiographic occlusion balloon catheter inflated in the hepatic artery, with previous placement of a vascular stent in order to prevent iatrogenic arterial lesions, and followed by the intraarterial administration of Mitomycin C; finally, arterial hepatic embolization was performed by a gelatine sponge. The study is ongoing with a median follow up of 8 months (range 2-12). Partial response was observed in 1/13 patients (8%), stable disease in 8/13 patients (61%), while progressive disease occurred in 4/13 patients (31%). Nine patients are still alive, and four patients died for hepatic progressive disease, three of them heavily pre-treated with multiple lines of chemotherapy for advanced disease. Toxicity was mild; main side effects were anaemia and thrombocytopenia(Grade 3 both in 1/15 treatments), while fever, nausea and vomiting and upper abdominal pain were short-lasting and easily manageable. No iatrogenic lesion of the hepatic arterial wall occurred. These preliminary data, although the small number of patients and the short follow up, show that the procedure is safe and feasible, with a interesting percentage of clinical responses. In addition, the placement of an arterial stent have demonstrated to protect vascular wall ensuring a regular blood flow, so allowing to perform repeated treatments in responsive patients. The good tolerability of this therapeutic modality suggests further investigation in order to determine its efficacy even in combination with systemic chemotherapy and other locoregional treatments such as termoablative procedures and/or intraarterial antiblastic perfusions in patients affected by metastatic liver disease.