changing your setting. We'll assume that you are happy to receive all cookies on the BTG website.
TheraSphere® acts predominantly through radiation vs.
embolization, and its unique properties, including high activity per
sphere, enable high absorbed dose coverage to the tumor. The
ability of TheraSphere® to selectively deliver a high absorbed dose
to the tumor without compromising patient safety is fundamental
to achieving improved patient outcomes.
The observation that improved responses are seen above certain absorbed dose
thresholds opens the way for personalized dosimetry with glass
microspheres, with the ultimate goal of optimizing dose according
to patient-specific tumor characteristics.
The properties of TheraSphere® also allow for unique treatment options
in the clinic. Not being limited by the number of microspheres provides
flexibility to adjust radiation dose according to individual patient needs,
enabling clinical utility for downstaging, bridge to transplant, and
radiation segmentectomy. TheraSphere® has demonstrated treatment
success in a range of scenarios: curative or palliative, livers with single
or multifocal tumors, portal vein thrombosis (PVT), and using segmental
or lobar approaches.3–8
TheraSphere® uses radiation as its primary mode of action for SIRT or TARE, a procedure in which glass microspheres
containing radioactive Y90 are delivered to the tumor vasculature via transfemoral catheterization of the hepatic artery.46
TheraSphere® capitalizes on the uniquely organized dual blood supply to the liver, which occurs through the hepatic artery and
the portal vein.9 In liver cancer, tumor blood supply is almost exclusively (80%–100%) from the hepatic artery.9 In contrast,
normal liver tissue receives most of its blood flow (75%) from the portal vein.10
The high specific activity of TheraSphere® glass microspheres means that fewer are administered to achieve the desired dose.
As a result, glass microspheres are microembolic are minimally embolic and do not occlude macrovessels.11 Since vessel
patency is maintained, subsequent arterial therapies are possible.7,11 TheraSphere® microspheres penetrate the tumor
arteriolar capillaries, where they emit lethal beta radiation that is localized to the surrounding tumor tissue.11,12 The targeted
distribution of microspheres provides high absorbed dose coverage to the tumor while sparing normal tissue.4,5,11,12
ALT = alanine aminotransferase; AST = alanine aminotransferase; BCLC = Barcelona Clinic Liver Cancer;
cTACE = conventional transarterial chemoembolization; HCC = hepatocellular carcinoma; NET = neuroendocrine tumor;
PVT = portal vein thrombosis; SIRT = selective internal radiation therapy; TARE = transarterial radioembolization;
ULN = upper limit of normal; Y90 = yttrium-90
TheraSphere® is authorized by Federal Law for use in radiation treatment or as a neoadjuvant to surgery or transplantation in patients with unresectable hepatocellular carcinoma (HCC) who can have placement of appropriately positioned
hepatic arterial catheters. The device is also indicated for HCC patients with partial or branch portal vein thrombosis/occlusion, when clinical evaluation warrants the treatment. The effectiveness of this device for this use has not been demonstrated.1
Common adverse effects include fatigue, pain, and nausea. The majority of adverse effects are mild to moderate in severity and are manageable or resolve over time. For details on rare or more severe adverse effects, please refer to the TheraSphere
® Package Insert.
TheraSphere® treatment has shown encouraging results in particular patient types, including:
A systematic review of 24 published studies, involving 1,634 HCC patients treated with TheraSphere® (the largest ever conducted for Y90 TARE), demonstrated that the majority of adverse events are mild to moderate in severity and
are manageable or resolve over time.1,10,33 Common adverse effects include fatigue, pain, and nausea, and may occur throughout the first week after treatment.1,3,5,7 Physicians describe these symptoms as similar to those of the
common flu. Some patients may experience loss of appetite and temporary changes in liver blood tests.1,3,5,7 Rare but more severe side effects are possible.
The physician should always take the below-noted pre-treatment high-risk factors into consideration for each patient when making decisions regarding the use of TheraSphere® for treatment:1
ALT = alanine aminotransferase; AST = alanine aminotransferase; BCLC = Barcelona Clinic Liver Cancer; cTACE = conventional transarterial chemoembolization; HCC = hepatocellular carcinoma; NET = neuroendocrine tumor; PVT = portal vein thrombosis; SIRT
= selective internal radiation therapy; TARE = transarterial radioembolization; ULN = upper limit of normal; Y90 = yttrium-90