Radioembolization of Secondary Hepatic Malignancies

Abstract

Cancer has become the leading cause of mortality in America, and the majority of patients eventually develop hepatic metastasis. As liver metastases are frequently unresectable, the value of liver-directed therapies, such as transarterial radioembolization (TARE), has become increasingly recognized as an integral component of patient management. Outcomes after radioembolization of hepatic malignancies vary not only by location of primary malignancy but also by tumor histopathology. This article reviews the outcomes of TARE for the treatment of metastatic colorectal cancer, metastatic breast cancer, and metastatic neuroendocrine tumors, as well as special considerations when treating metastatic disease with TARE.

Keywords: hepatic metastasis; liver-directed therapies; radioembolization.

Fig. 1

A 60-year-old female diagnosed with stage IV colon cancer (primary in sigmoid colon; KRAS/BRAF wild-type) with liver metastasis and was initially treated with FOLFOX + bevacizumab for ∼9 months before undergoing radioembolization. Right hepatic artery and left hepatic artery radioembolizations were performed 5 weeks apart. ( a and b ): Pretreatment contrast-enhanced CT demonstrates multiple hypoenhancing index lesions in the right hepatic lobe. Similar-appearing metastases were also present in the left hepatic lobe (not shown). ( c ) Right hepatic artery angiography demonstrates vascular supply to segments 5–8 as well as a small caudate branch. There is minimal abnormal tumor blush in the hepatic dome; however, cone beam CT (not shown) demonstrates vascular supply to multiple metastases in the right liver. 98.2 mCi yttrium-90 was administered. ( d ) Left hepatic artery angiography demonstrates vascular supply to segments 2–4 with visualization of multiple masses. 38.9 mCi yttrium-90 was administered. ( e and f ) Nine months post-radioembolization contrast-enhanced CT demonstrates stable lesions in the right hepatic lobe. Increased intralesional attenuation had been stable on multiple prior posttreatment CT scans and was unchanged. ( g and h ) Twenty-one months post-radioembolization contrast-enhanced CT demonstrates progression of liver metastasis as well as cirrhotic morphology of the liver with new ascites.

Fig. 2

A 52-year-old female diagnosed with stage IV left breast invasive ductal carcinoma (ER ⁺ /PR ⁻ , PIK3 mutation ⁺ ) with metastatic disease to the bone who was initially treated with left breast mastectomy, radiation, tamoxifen, and denosumab. Five years later, she developed liver metastasis. Despite multiple additional systemic treatment regimens (anastrozole/palbociclib/abemaciclib/letrozole), her liver metastasis progressed; so, she was treated with radioembolization. Right hepatic artery and left hepatic artery radioembolizations were performed 4 weeks apart. ( a and b ) Pretreatment contrast-enhanced CT demonstrates two index hepatic metastases in segments 7 and 8. ( c ) Posttherapy bremsstrahlung image demonstrates adequate administration into the right hepatic lobe. 76.2 mCi yttrium-90 had been administered via the right hepatic artery. ( f ) Left hepatic artery angiography demonstrates vascular supply to segments 2–4; however, the metastatic lesions are not well visualized. 56.3 mCi yttrium-90 was administered. ( d and e ) Fifteen months post-radioembolization contrast-enhanced CT demonstrates decreased size of the hepatic lesions. There was interval development of cirrhotic morphology of the liver, ascites, and splenomegaly. Although the hepatic metastasis did not progress, the patient developed new splenic metastasis.

Fig. 3

A 57-year-old Filipino male with a history of chronic diarrhea diagnosed with stage IV well-differentiated neuroendocrine tumor with metastasis to the liver and lung. Patient was initially treated with Sandostatin, everolimus, and denosumab and ultimately underwent radioembolization 4 months later due to worsening symptoms. Right hepatic artery and left hepatic artery radioembolizations were performed 8 weeks apart. ( a ) Pretreatment contrast-enhanced CT demonstrates innumerable arterially enhancing, ill-defined massed throughout the liver. An enhancing pancreatic mass was also identified (not shown). ( b ) Right hepatic artery angiography demonstrates vascular supply to segments 5–8 and 4A; however, the metastases are not well-visualized on this image. 37.9 mCi yttrium-90 was administered. ( c ) Left hepatic artery angiography demonstrates vascular supply to segments 2, 3, and 4B with multiple hypervascular lesions visualized. 10.29 mCi yttrium-90 was administered. ( d ) Sixteen months and ( e ) 23 months post-radioembolization, contrast-enhanced CT demonstrates homogenous enhancement of the liver with significant improvement of arterially enhancing metastasis and no new metastasis. ( f ) Thirty months post-radioembolization, contrast-enhanced CT demonstrates new hepatic metastasis.