Surgical Management of Hepatic Breast Cancer Metastases

In general, surgery has no role in the curative treatment of metastatic breast cancer. Metastatic breast cancer is considered incurable, associated with an average survival of 18 to 24 months. Certain factors such as hormone- receptor negativity, HER2/neupositive disease, and a short disease-free interval portend a poor prognosis. The liver is not usually a site of initial failure-less than 15% of patients fit this pattern.[1] Even fewer are candidates for surgical resection due to extrahepatic disease. Eventually, over half of all patients with metastatic disease will have liver metastasis during their clinical course. With the advent of newer chemotherapeutic agents, endocrine therapy, and targeted therapy, prolonged survival and delayed disease progression have been shown in some patients. Recently, chemotherapy trials of hepatic-only metastasis (European Organization for Research and Treatment of Cancer [EORTC] 10923 and 10961) revealed median survivals of 22.7 and 27 months, respectively.[2] Overview of Outcomes
Podnos and Wagman have reviewed the literature on surgical resection and ablation of hepatic breast cancer metastases. Most studies have been small with a heterogeneous group of patients-with and without breast cancer-included in their reports. Earlier experience reported dismal outcomes with very poor 5- and 10-year survival rates. With the improvement in surgical and anesthetic technique, more recent studies have shown acceptable morbidity and mortality with surgical resection of liver metastasis. A few small studies with R0 resections in patients free of measurable extraheptic disease have revealed reasonable and improved median survivals.[3,4] A second avenue of interest is the use of intraoperative or percutaneous ablation techniques. Some groups have shown reasonable success in cytoreduction and ablation, although curative ablation is still controversial for most metastatic tumors. The ablative methods have also been tried in breast cancer-only hepatic metastasis in a small number of patients and are an emerging area of interest. Future Directions
What should be carefully pointed out is that these are small studies, not prospective and not randomized. Selection bias is inevitable in the studies published to date, and concluding that carefully selected patients with liveronly metastasis should undergo resection is a route we are not ready to endorse. Looking at ways to study these patients in multi-institutional, randomized prospective studies would better answer the question of surgical therapy in liver-only metastasis. In terms of the ablative technology, initially ethanol and cryoablation were used, and now radiofrequency ablation has become the preferred technique. These ablative techniques in general are used for nonresectable tumors, and thus, a curative oncologic ablation has not been proven. With the improvement of surgical technique and critical care, anesthesia combined with chemotherapy, hormonal therapy, and targeted therapies, surgical resection of isolated intrahepatic metastasis from breast cancer should be explored. Since hepatic- only metastasis is a fairly un- common event, the resources of multiple centers would need to be combined to adequately explore this question. With the increased use of novel imaging techniques such as positron-emission tomography/computed tomography (PET/CT) and the development of other molecular imaging techniques, patients with extrahepatic disease not seen on conventional imaging could be removed from consideration, further stratifying patients who would be amenable to surgical resection. It is not unreasonable to think that there will be a day when selected patients with metastatic disease to the liver can be offered surgical or ablative resection and may expect improved survival. However, we believe that day is not yet upon us.