Interstitial percutaneous therapies in primary and secondary liver tumors

Multiple percutaneous interstitial systems to induce intrahepatic tumor necrosis are classifiable in two major groups: those using chemical agents (ethanol and acetic acid) and those adopting thermal effects (hot saline, radiofrequency, laser and microwave). Indication, technique and results of percutaneous ethanol injection (PEI) are considered. In the case of single hepatocellular carcinoma (HCC), < 5 cm and associated with cirrhosis Child class A long-term results of PEI are comparable with those of best surgical series with 5-years survival which range from 47 to 51%. No mortality and recurrence rates similar to those of surgical cases make PEI as an alternative to surgical resection although the difficulties in comparing retrospectively the different experiences do not enable definitive conclusions. In the case of liver metastases from colorectal cancer or endocrine tumors, which seem more sensitive to locoregional therapies, complete response rates are not adequate yet being 86%, 26%, 11% and 0% respectively in the case of < 2 cm, 2-3 cm, 3-4 cm and > 4 cm lesions and moreover no definitive data are available about long-term prognosis. Waiting for further validation about the encouraging data obtained with the other interstitial methods and in particular with radiofrequency (RF) and laser interstitial photocoagulation (FLI), PEI is a valid alternative to surgery for selected HCC patients and is a good palliation in cases with not resectable liver metastases which are anyway suitable for locoregional treatments.