What do I Have? Management of Metastatic Liver Tumors from Other Sites
Tumor Outside the Liver
Under most circumstances the presence tumor outside the liver is usually an absolute contraindication to liver resection/ablation. Outside of a scientific study designed to answer a specific question, there are few cases where a major liver operation is warranted when there is tumor outside the liver. Further, there are certain diseases, such as pancreatic cancer, where surgical treatment of metastases does not promote longer survival. It therefore is critical that an individual considering resection of liver metastases from these other forms noncolorectal, nonneuroendocrine, nonrenal cell undergo a very careful evaluation to rule out the presence of distant metastases (bone, lung, abdomen). Tests to rule out these sites of distant metastasis will include a careful physical examination, laboratory tests and a variety of x-rays (chest x-ray, chest CT scan, abdominal CT scan, bone scan and over the next few years PET scan). Only after metastasis outside the liver has been ruled out should any consideration be given to undertaking a major liver directed procedure.
The presence of fewer lesions, or the development of disease long after the treatment of the primary tumor, is associated with a more favorable outlook.
Debulking/Cytoreduction
The issue of debulking/cytoreduction (reducing, but not eliminating, the amount of visible tumor remaining in the body) becomes important in the consideration of the treatment of metastatic tumors. The theory of debulking is that the reduction of tumor volume in the body will allow radiation or chemotherapy will be more effective (because there is less tumor to treat). Additionally, debulking may increase on the ability of one's own immune system to fight the tumor. Patients with certain cancers, for example ovarian cancer and melanoma, may benefit from tumor debulking. Beyond these two diseases there is little evidence that debulking alters the natural history of any of the other disease processes being considered here.
Minimally invasive ablation techniques
Percutaneous ethanol injection, radiofrequency ablation, and cryosurgery are becoming increasingly available throughout the country and the world. You must be very careful regarding the application of these technologies because the long-term outcomes have not been clearly demonstrated.
Questions remain as to whether tumor ablation has the same benefit has surgical resection. The safety profile of ablation techniques may be better then resection, but in diseases in which resection has no benefit it is unlikely that ablation will be beneficial either.
Ablative techniques should be applied only to patients who meet criteria for surgical resection but who have other reasons not to proceed with resection. In other words, you must meet the criteria for resection (most importantly the absence of extrahepatic metastases) prior to being considered for tumor ablation. Caution should be advised to those patients who are offered a "it won't hurt, it might help" approach to liver tumor ablation. These techniques have complications, are unproven in the long-term and are expensive. Treatment with these newer techniques should be offered under an institutional protocol in order to learn the safety and effectiveness of these techniques, the benefits and appropriate uses of them. You should be considered for treatment protocols whenever possible so as to monitor the safety and effectiveness of these treatments.
