IMAGE-GUIDED
CRYOABLATION
LIVER METASTASIS
Who is at risk?
When cancer spreads from its primary site to another part of the body, it is said to metastasize. Liver metastases are tumors that have grown in the liver from cancerous cells that migrated from a cancer that originated somewhere else. This is also called “secondary cancer.”
The risk of the spread of cancer to the liver varies. It depends on many factors, some of which are not clearly understood by the scientific community. Some factors that we know influence the risk include the site of the original cancer, blood flow patterns, and the characteristics of the different cancer cells. Cancerous cells can detach from the site of the original cancer anywhere in the body and be transported via the bloodstream to the liver. Because one of the liver's main functions is to filter the blood, these cancer cells can remain behind and colonize in the liver, growing into tumors.
Cancers of the gastrointestinal tract, most commonly
colorectal cancer, often spread to the liver because
blood flows directly from these organs to the
liver. In about 20% of colorectal cancer cases,
the cancer has already metastasized to the liver
by the time the primary cancer is originally diagnosed.
However, it is also possible that a metastatic
tumor may not appear for months or even years
after the primary tumor is removed. Pancreatic,
stomach and esophageal cancers are other GI cancers
that sometimes spread to the liver.
Breast cancer, lung cancer, and melanoma often spread to the liver, as well. How liver metastases are treated depends on many factors, including the primary cancer site, the volume of liver tissue involved, whether there is one or several liver tumors, whether it has spread to other organs, and the overall medical condition of the patient. When the tumor is localized to only a few areas of the liver, it is possible that the cancer may be removed surgically. Overall, however, only 15-20% of liver tumors are able to be resected through traditional surgery.
In situations when metastasis is limited to the liver but the tumors are considered inoperable, it may be possible to treat the cancer with a localized therapy such as cryotherapy, radiofrequency ablation (RFA), or injection of toxic substances may also be used to kill tumors. When large areas of the liver are involved, liver-directed chemotherapy (infusing chemotherapy directly into the liver), or embolization (blockage of blood flow to parts of the liver) may be used.
The introduction of very thin 17g (1.47mm) MRI compatible cryoablation needles and ultra-thin thermal sensors allows cryoablation treatment for liver cancer to be performed safely as a minimally-invasive procedure under CT or MRI image guidance by a physician specializing in interventional radiology. The ability to perform the procedure percutaneously may expand the patient population that can receive curative as well as palliative treatment for hepatic malignancies. |
