Radioembolization complications

The more mature data currently available in the literature regarding the use of SIR-Spheres in metastatic breast cancer have been recently reported in a peer-reviewed format by Coldwell and colleagues [37]. The authors evaluated the feasibility, side effects, and complications of radioembolization in the treatment of breast cancer metastases to the liver. Enrollment was limited to those patients who had an Eastern Cooperative Group performance score of 0 or 1 and an expected survival of at least 3 months. All patients have been previously treated with systemic chemotherapy and/or trastuzumab. Patients were excluded if brain metastases were present or total bilirubin exceeded 2 mg/dl. Bone metastases did not exclude patients. Baseline PET scans were obtained and patients were followed with CT and PET scans every 3 months. 

Radioembolization represents an effective tool for the treatment of primary and secondaryliver tumors. Adequate use of this therapy requires knowledge and a multidisciplinary effort in order to obtain optimal results and avoid therapy-specific complications. A great deal of research has been undertaken in order to understand the angiographic, technical... 

The most common complications of radioembolization include non-target radiation (pancreatitis, GI ulcers, cholecystitis), radiation pneumonitis, radiation induced liver disease (radiation hepatitis) and biliary complications. 

Overall, the incidence of complications after radioembolization is low, if patients selection and preparatory examinations are performed thoroughly, if aberrant vessels are embolized and if dose administration is performed very carefully. 

Histopathological basis. Radiation-induced cholecystitis or gall bladder infarction is a rare complication of radioembolization and is due to the radiation effect of the microspheres. Unlike transarterial chemoembolization, Y treatment does not produce a significant embolic effect [25] (Fig. 14.2). Animal studies performed in dogs to examine the tolerance to radioembolization with Y labelled resin microspheres have shown that cholecystitis is encountered to some extent in almost all of the animals who received radioactive microspheres, but was absent in the animals infused with nonradioactive microspheres [26]. Similar studies performed in pigs that received Sirtex particles demonstrated the presence of particles in the gall bladder without inflammatory wall changes [27]. 

Background. Biliary complications both intra- and extrahepatic following administration are due to the embolic and radiation induced necrosis of the biliary ducts [29]. In contrast to the normal liver parenchyma, the intrahepatic bile ducts do not have a dual blood supply and are fed exclusively from the hepatic arterial branches that give off a vascular plexus (peribiliary capillary plexus) around the bile ducts. This microscopic peribiliary arterial plexus has a similar diameter to that of the microspheres (10-60 pm, mean 35 pm). Therefore, ischaemia of the intrahepatic bile ducts can occur after radioembolization [25]. 

Radioembolization is a newly developed technique which takes advantage of the synergy of endovascular embolization and of brachy therapy in the treatment of cancer. It offers new perspectives for achieving local control of tumor growth with a low rate of complications. 

Such complications from radioembolization are exceedingly rare allowing the vast majority of patients to have this procedure on an outpatient basis. Rarely, treatment may be complicated by post-embolization syndrome and symptomatic support may be necessary. Nontarget embolization can be all but eliminated by meticulous technique and pre-procedure planning... 

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