Radioembolization is an established treatment modality that has been subjected to many improvements over the last decade. Developments are occurring at a high pace, affecting patient selection and treatment. The aim of this CME review is therefore to provide an overview of current practice, with a focus on recent developments in the field of radioembolization. Several practical issues and recommendations in the application of radioembolization will be discussed, ranging from patient selection to treatment response and future applications.

Purpose: Accurately predicting treatment response in metastatic colorectal cancer (mCRC) is critical to avoid unnecessary toxicity and improve patient outcomes. Patient-derived organoids (PDO) are promising models, but larger prospective studies are needed to confirm their predictive value. Experimental Design: Patients with mCRC underwent a metastatic biopsy for PDO establishment, before starting new systemic treatment. Predictors of PDO establishment were identified. PDOs were incubated with a seven-drug panel, including the patient’s treatment, to determine drug sensitivity as measured by CyQUANT cell viability [area under the nonfitted “curve” of the raw viability or growth rate inhibition values (AUC and GRAUC) and concentration that gives half-maximal viability or GR inhibition (IC50 and GR50)]. Patient response was measured by size change of biopsied and all target lesions. The diagnostic performance was evaluated by positive predictive value, negative predictive value, and area under the ROC curve. Additionally, the association between PDO response and survival was assessed. Results: A total of 232 patients were included, and 205 biopsies were obtained. PDO establishment success increased from 22% to 75%, yielding 52% overall. Male sex, increased lactate dehydrogenase, biopsy in academic hospitals, optimized culture conditions, and experience were related to PDO establishment success. In this interim analysis, focused on oxaliplatin-based doublet chemotherapy, 42 PDOs were screened. PDO drug sensitivity significantly correlated with the response of the biopsied lesion (R = 0.41–0.49, P < 0.011) and all target lesions (R = 0.54–0.60, P < 0.001) for all treatments combined. The 5-fluorouracil and oxaliplatin PDO screens demonstrated high predictive accuracy (positive predictive value: 0.78; negative predictive value: 0.80; area under the ROC curve: 0.78–0.88) and were associated with progression-free survival and overall survival (P = 0.016 and 0.049). Conclusions: We identified predictors for successful mCRC PDO establishment and validated that PDOs can accurately predict patient outcomes during systemic treatment, specifically with 5-fluorouracil and oxaliplatin.

Routine work-up for transarterial radioembolization, based on clinical and laboratory parameters, sometimes fails, resulting in severe hepatotoxicity in up to 5% of patients. Quantitative assessment of the pretreatment liver function and its segmental distribution, using hepatobiliary scintigraphy may improve patient selection and treatment planning. A case series will be presented to illustrate the potential of this technique. Hepatocellular carcinoma patients with cirrhosis (Child-Pugh A and B) underwent hepatobiliary scintigraphy pre- and 3 months post-radioembolization as part of a prospective study protocol, which was prematurely terminated because of limited accrual. Included patients were analysed together with their clinical, laboratory and treatment data. Pretreatment-corrected 99mTc-mebrofenin liver uptake rates were marginal (1.8–3.0%/min/m2), despite acceptable clinical and laboratory parameters. Posttreatment liver functions seriously declined (corrected 99mTc-mebrofenin liver uptake rates: 0.6–2.4%/min/m2), resulting in lethal radioembolization-induced liver disease in two out of three patients. Hepatobiliary scintigraphy may be of added value during work-up for radioembolization, to estimate liver function reserve and its segmental distribution, especially in patients with underlying cirrhosis, for whom analysis of clinical and laboratory parameters may not be sufficient.

Article: Toxicity comparison of yttrium-90 resin and glass microspheres radioembolization - The Quarterly Journal of Nuclear Medicine and Molecular Imaging 2022 Jun 28 - Minerva Medica - Journals