Procedure details

SIRT with Y-90 resin microspheres is typically a 2-stage process. While preparing patients for treatment with yttrium microspheres, an initial planning angiography is performed 1–2 weeks prior to treatment day (Fig. 2).

After the angiogram, technetium-macroaggregated albumin is injected through the microcatheter into the hepatic artery. A single-photon emission computerized tomography is then performed to assess the possible gastrointestinal or pulmonary shunt. If there is no shunt to the nontargeted organs or the shunt rate to the lung is below 20%, the patient is considered suitable for radioembolization.

The second stage of radioembolization is the treatment itself. The goal of the procedure is to allow microspheres to directly target liver tumors via the hepatic artery with enough focused radiation to kill tumor cells while minimizing the exposure to the remaining healthy liver tissue.

Treatment evaluation

The tumor response of patients treated with TARE is evaluated with cross-sectional abdominal imaging, commonly computed tomography (CT) or magnetic resonance imaging (MRI). There is no standard protocol for the timing of postprocedure imaging. At UMC Ljubljana, follow-up imaging with either CT or MRI is obtained 2 months after the procedure and every 3–6 months thereafter (Fig. 3). RECIST and mRECIST criteria are used to determine tumor response. During follow-up outpatient visits, patients are assessed for adverse events attributable to TARE, namely abdominal pain, nausea, vomiting, and fatigue. 

Patients

From June 2012 to December 2018, 19 HCC patients (11 male, 8 female; the median patient age 63 (range 45-85 years); 12 patients with Child-Pugh class A liver cirrhosis, 4 with class B, 3 without cirrhosis) underwent SIRT as a treatment for hepatocellular carcinoma.

Methods

A total of 19 HCC patients (17 BCLC B stage, 2 BCLC C stage) not eligible for DEB-TACE, were treated with Y-90 microspheres and sorafenib (200 mg two times per day for one week before increasing the dose to 400 mg per day) or SIRT alone. In 6 patients sorafenib was initiated on the third day after the SIRT procedure.

Of 19 patients, 9 received lobar or selective SIRT in a single session, and 10 patients received radioembolizations of both liver lobes. Additional procedures were performed in 5 patients due to the progression of the disease. One patient was treated with the intention to downsizing the tumor  prior to surgery.

Patients stayed in the hospital for 24 hours. Radiation protection and patient isolation after the implantation of yttrium were not required due to its short averagge (2.5 mm) tissue penetration.

Results

In 19 patients we performed a total of 24 interventions (range 1-3 procedures). The median value of the implanted Y-90 activity was 1.4 GBq (range: 0.42-3.57). After a median follow-up of six months, disease control rate (complete response, partial response, and stable disease) was 73.7 %., a progression of the disease occurred in 5 patients (26.3%). Three patients suffered from mild postradioembolization syndrome in terms of pain, and were conservatively treated with nonsteroidal anti-inflammatory drugs (NSAID). No deterioration of liver function and no indicators of radioembolization-induced liver disease (REILD) were observed.