Intra-hepatic Abscopal Effect Following Radioembolization of Hepatic Metastases

Abstract

Purpose To search for abscopal effects (AE) distant to the site of radiation after sequential Yittrium-90 (Y-90) radioembolization (RE) of liver malignancies. Methods and Materials In this retrospective analysis, all patients treated by RE between 2007 and 2018 (n = 907) were screened for the following setting/conditions: sequential RE of left and right liver lobe in two sessions, liver-specific MRI (MRI1) acquired max. 10 days before or after first RE (RE1), liver-specific MRI (MRI2) acquired with a minimum time interval of 20 days after MRI1, but before second RE (RE2). No systemic tumor therapies between MRI1 and MRI2. No patients with liver cirrhosis. Metastases > 5 mm in untreated liver lobes were compared in MRI1 and MRI2 and rated as follows: same size or larger in MRI2 = no abscopal effect (NAE); > 30% shrinkage without Y-90 contamination in SPECT/CT = abscopal effect (AE). Results Ninety six of 907 patients met aforementioned criteria. Median time-frame between RE1 and MRI2 was 34 (20–64) days. These 96 cases had 765 metastases which were evaluable (median 5(1–40) metastases per patient). Four patients could be identified with at least one shrinking metastasis of the untreated site: one patient with breast cancer (3 metastases: 0 NAE; 3 AE), one patient with prostate cancer (6 metastases: 3 NAE; 3 metastases > 30% shrinkage but possible Y-90 contamination) and two patients with shrinkage of one metastasis each but less than 30%. Conclusion Our retrospective study documents AE after RE of liver tumors in 1 out of 96 cases, 3 other cases remain unclear.

Selective Internal Radiotherapy Changes the Immune Profiles of Extracellular Vesicles and Their Immune Origin in Patients with Inoperable Cholangiocarcinoma

“…The radiation leads to necrosis of the tumor tissue and invasion of immune cells [ 10 ]. It still remains controversial if, due to the immune response to a therapy, an abscopal effect (which describes immune cells getting primed by undergoing tumor cells, subsequently “attacking” out-of-the-field metastasis) can be observed [ 11 ]. This highlights the unique role of the immune system and intercellular communication in cancer diagnosis, therapy, and especially in ablative therapy procedures.…”

Yttrium‐90 radioembolization‐induced abscopal effect on hepatocellular carcinoma

“…[1][2][3][4][5] Furthermore, after Yttrium-90 radioembolization, only three cases of abscopal effect have been published on patients with hepatic metastases of squamous cell carcinoma and breast carcinoma. [6][7][8] Therefore, to our knowledge this is the first case report of a potential abscopal effect on HCC after radioembolization.…”

Complications Risk Assessment and Imaging Findings of Thermal Ablation Treatment in Liver Cancers: What the Radiologist Should Expect

“…With regard to patients, both HCC patients and colorectal liver metastases patients [ 105 , 106 , 107 , 108 , 109 , 110 , 111 , 112 , 113 ] could have impaired liver function due to cirrhosis or drug-induced liver injury [ 114 ], so, they are at increased risk of bleeding ( Figure 1 ) or biliary damage ( Figure 2 ). In addition, in immunocompromised patients, the risk of infection of the ablated area is high, with consequent risk of liver abscess [ 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 ].…”