SIR-Spheres microspheres are used to treat patients with unresectable
liver cancer
Liver cancer (also known as hepatic cancer, primary hepatic cancer, or primary hepatic malignancy) is cancer that starts in the liver. Liver cancer can be primary (starts in liver) or secondary (meaning cancer which has spread from elsewhere to th ...
. These are mostly patients with
hepatocellular carcinoma
Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide.
It occurs in t ...
(HCC), metastatic
colorectal cancer
Colorectal cancer (CRC), also known as bowel cancer, colon cancer, or rectal cancer, is the development of cancer from the colon or rectum (parts of the large intestine). Signs and symptoms may include blood in the stool, a change in bowel m ...
(mCRC), or metastatic
neuroendocrine tumours
Neuroendocrine tumors (NETs) are neoplasms that arise from cells of the endocrine (hormonal) and nervous systems. They most commonly occur in the intestine, where they are often called carcinoid tumors, but they are also found in the pancreas, lun ...
(mNET).
Therapy goals are local disease control, downstaging to resection, bridging to transplantation, and extended survival.
Description
SIR-Spheres microspheres contain resin based
microspheres with an average diameter between 20 and 60
micrometre
The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...
. The microspheres are impregnated with
90Y, a
beta radiating isotope of
yttrium
Yttrium is a chemical element with the symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and has often been classified as a "rare-earth element". Yttrium is almost always found in com ...
with a
half-life
Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...
of 64.1 hours.
[ ]
Mode of action
Once injected into the hepatic artery via a
catheter
In medicine, a catheter (/ˈkæθətər/) is a thin tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgical procedure. Cath ...
by an interventional radiologist the microspheres will preferably lodge in the
vasculature
The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...
of the tumour. The radiation will lead to damage of tumour tissue and, in the best case to a complete elimination of the tumour. Due to the half-life almost all of the radiation is delivered within two weeks. After one month almost no radioactivity will remain.
The procedure is also known as selective internal radiation therapy (SIRT) or radioembolization.
See also
*
TheraSphere
TheraSphere is a radiotherapy treatment for hepatocellular carcinoma (HCC) that consists of millions of microscopic, radioactive glass microspheres (20–30 micrometres in diameter) being infused into the arteries that feed liver tumors. These ...
*
Sirtex
References
External links
Sirtex
{{Radiation oncology
Radiation therapy procedures