Intra-arterial therapies for metastatic colorectal cancer

Abstract

Intra-arterial therapies for unresectable hepatic metastases from colorectal cancer include radioembolization (RE) with yttrium-90 microspheres, transarterial chemoembolization (TACE), hepatic arterial infusion, and percutaneous hepatic perfusion using an organ isolation system. In this article, we discuss our approach toward treatment selection, followed by details of how RE and TACE are performed at our institution.

Keywords: colorectal cancer; drug-eluting beads; irinotecan; liver metastases; radioembolization.

Figure 1

Complete response to first-line treatment with radioembolization (RE) using yttrium-90 (⁹⁰Y) resin microspheres. (A) Frontal maximum intensity projection of positron emission tomography scan of a patient with liver metastases from colorectal cancer prior to treatment demonstrated large bilobar hypermetabolic hepatic lesions. (B) Follow-up imaging studies 3 and 6 months after whole-liver RE treatment showed complete response of the metastases, which was sustained 1 year later while the patient was receiving systemic chemotherapy.

Figure 2

Embolization of parasitized extrahepatic arteries (EHAs). (A) Arteriogram of the right inferior phrenic artery demonstrated parasitized collateral vessels supplying the posterior superior medial periphery of a large hepatic colorectal cancer metastasis via the bare area. After prophylactic coil embolization of a left phrenic arterial branch, the tumor-supplying parasitized branches were embolized to stasis using 500- to 700-µm Embospheres (Merit Medical Systems, Inc., South Jordan, UT). (B) Subsequent cone-beam C-arm computed tomography performed with contrast administered via the common hepatic artery demonstrated contrast enhancement of the entire posterior right hepatic lobe lesion all the way to the capsule, confirming restoration of intrahepatic arterial supply to portions of the lesion previously supplied by parasitized EHAs (arrows).

Figure 3

Hepatic artery skeletonization in preparation for radioembolization (RE). (A) Common hepatic arteriogram portrayed numerous hepaticoenteric communications, as well as anatomical variants of the gastroduodenal (black arrow) and posterior superior pancreaticoduodenal (white arrow) arteries originating from the right hepatic artery. (B) Endovascular skeletonization was performed by prophylactic coil embolization of all recognized hepaticoenteric anastomoses including the right gastric artery (1), dorsal pancreatic artery (2), gastroduodenal artery (3), posterior superior pancreaticoduodenal artery (4), and a supraduodenal artery originating from the right hepatic artery (5). RE was performed by separate microsphere administrations via the left and right main hepatic arteries.