Potential complications of falciform artery (FA) nontarget embolization following transarterial hepatic chemoradiation therapies have been described including supraumbilical skin rash, epigastric pain and skin necrosis with delivery of embolic agents into the terminal capillaries of the FA. Injection of technetium-99m macroaggregated albumin (MAA) during pretreatment planning studies allows for identification of potential variant anatomy, otherwise unseen on standard angiography, that may place a patient at risk for nontarget radioembolization prior to yttrium-90 (Y90) therapy.
The purpose of this study is to identify all cases at our institution of FA radiotracer uptake during MAA pretreatment planning prior to Y90 administration utilizing SPECT/CT. Our goal is to describe the clinical consequences of reporting or failing to report FA uptake and the need for possible intervention prior to Y90 in order to avoid potential complications.
A retrospective review was performed for all MAA injections from 2014-2017 (n= 116). Of these cases, 103 patients underwent SPECT/CT at the time of MAA injection, which were reviewed for potential FA radiotracer uptake. The patient record was then reviewed for all cases of positive FA uptake to determine if intervention was performed at the time of the procedure and if there were postprocedure adverse effects. This study was performed under IRB approval.
Of 103 patients reviewed, 10 showed FA uptake (9.7%) on initial MAA injection for pretreatment planning. Of these, the FA was visualized on 1/10 angiographic exams prior to treatment. Prospectively only 4/10 nuclear medicine MAA reports mentioned uptake in the FA. An ice pack was placed at the umbilicus to minimize symptoms in all 4/10 patients. Coil embolization of the FA prior to Y90 was performed in 1/10 cases. No immediate or latent postprocedure complications were directly related to Y90.
There is limited knowledge regarding the implications of nontarget radioembolization of the FA after Y90 or the need for preprocedure intervention. While MAA pretreatment planning is instrumental in identifying uptake in the FA, it is often underreported. Greater attention must be paid to this anatomic variant to limit complications such as peri-umbilical rash and necrosis. However, small amounts of radiotracer uptake in the FA are unlikely to result in such complications.