Disease control and failure patterns of unresectable hepatocellular carcinoma following transarterial radioembolization with yttrium-90 microspheres and with/without sorafenib

BACKGROUND Impressive survival outcome of our previous study in unresectable hepatocellular carcinoma(HCC)patients undergoing yttrium-90 glass microspheres transarterial radioembolization(TARE)with/without sorafenib according to individuals’disease burden,i.e.,intrahepatic tumor load(IHT)and adverse disease features(ADFs)might partly be confounded by other treatments and underlying hepatic function.Therefore,a dedicated study focusing on treatment response and assessment of failure patterns might be a way to improve treatment outcome in addition to patient selection based on the disease burden.AIM To assess the tumor response,disease control and patterns of disease progression following TARE with/without sorafenib in unresectable HCC patients.METHODS This retrospective study was conducted in successful TARE procedures with available pre-and post-treatment imaging studies(n=169).Three treatment subgroups were(1)TARE only(TARE_alone)for IHT≤50%without ADFs,i.e.,macrovascular invasion,extrahepatic disease(EHD)and infiltrative/ill-defined HCC(n=63);(2)TARE with sorafenib(TARE_sorafenib)for IHT>50%and/or presence of ADFs(n=81);and(3)TARE only for patients who could not receive sorafenib due to contraindication or intolerance(TARE_no_sorafenib)(n=25).Objective response rate(ORR;consisted of complete response(CR)and partial response(PR)),disease control rate(DCR;consisted of CR,PR and stable disease)and failure patterns of treated,intrahepatic and extrahepatic sites were assessed using the modified response evaluation criteria in solid tumors.Time to progression(TTP)was calculated from TARE to the first radiologic progression at any site using Kaplan-Meier method.Identification of prognostic factors for TTP using the univariate Kaplan-Meier method and multivariate Cox proportional hazard model were performed in major population subgroups,TARE_alone and TARE_sorafenib.RESULTS The median radiologic follow-up time was 4.4 mo(range 0.5-48.8).In treated area,ORR was highest in TARE_sorafenib(53.1%),followed by TARE_alone(41.3%)and TARE_no_sorafenib(16%).In intrahepatic area,DCR remained highest in TARE_sorafenib(84%),followed by TARE_alone(79.4%)and TARE_no_sorafenib(44%).The overall DCR was highest in TARE_alone(79.4%),followed by TARE_sorafenib(71.6%)and TARE_no_sorafenib(40%).Dominant failure patterns were intrahepatic for both TARE_alone(44.5%)and TARE_sorafenib(38.4%).Extrahepatic progression was more common in TARE_sorafenib(32%)and TARE_no_sorafenib(40%)than in TARE_alone(12.7%).TTP was longest in TARE_alone(8.6 mo;95%CI:3.4-13.8),followed by TARE_sorafenib(5.1 mo;95%CI:4.0-6.2)and TARE_no_sorafenib(2.7 mo;95%CI:2.2-3.1).Pre-existing EHD(HR:0.37,95%CI:0.24-0.56,P<0.001)was a sole prognostic factor for TTP in TARE_sorafenib with no prognostic factor for TTP in TARE_alone.CONCLUSION TARE with/without sorafenib according to individuals’disease burden provided DCR approximately 70%with intrahepatic progression as dominant failure pattern.Extrahepatic progression was more common in procedures with initially high disease burden.

Same day yttrium-90 radioembolization with single photon emission computed tomography/computed tomography: An opportunity to improve care during the COVID-19 pandemic and beyond

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has made it more challenging for patients to undergo yttrium-90(Y-90)radioembolization(RE).Same day Y-90 RE provides an opportunity to minimize logistical challenges and infection risk associated with COVID-19,thus improving patient access.AIM To describe the use of same day Y-90 RE with routine single photon emission computed tomography/computed tomography(SPECT/CT)in order to optimize therapy.METHODS All patients were selected for Y-90 RE through a multidisciplinary tumor board,and were screened and tested for COVID-19 infection per institutional protocol.A same day procedure was developed,consisting of angiography,imaging,and Y-90 resin particle delivery.Routine SPECT/CT after technetium-99m macroaggregated albumin(Tc-99m MAA)administration was performed for assessment of arterial supply,personalized dosimetry,and extrahepatic activity.Post-treatment Y-90 bremsstrahlung SPECT/CT was performed for confirmation of particle delivery,by utilization of energy windowing to limit signal from previously administered Tc-99m MAA particles.RESULTS A total of 14 patients underwent same day Y-90 RE between March and June 2020.Mean lung shunt fraction was 6.13%(range 3.5%-13.1%).Y-90 RE was performed for a single lesion in 7 patients,while the remaining 7 patients had treatment of multifocal lesions.The largest lesion measured 8.3 cm.All patients tolerated the procedure well and were discharged the same day.CONCLUSION Same day Y-90 RE with resin-based microspheres is feasible,and provides an opportunity to mitigate infection risk and logistical challenges associated with the COVID-19 pandemic and beyond.We recommend consideration of SPECT/CT,especially among patients with complex malignancies,for the potential to improve outcomes and eligibility of patients to undergo same day Y-90 RE.