Radioembolization for hepatocellular carcinoma: Statistical confirmation of improved survival in responders by landmark analyses

Clinical course of patients with hepatocellular carcinoma who experienced radiologic complete response after radioembolization

Purpose

The purpose of this study is to elucidate the patterns of recurrence of hepatocellular carcinoma and to analyze factors that can predict recurrence after complete response to radioembolization.

Materials and methods

A total of 289 consecutive patients who underwent radioembolization for the treatment of hepatocellular carcinoma at a single tertiary center were retrospectively reviewed. Baseline characteristics were collected and compared between the group showing complete response and the group showing noncomplete response. Data on recurrence status, time to recurrence, and the patterns of recurrence among the patients who showed radiologic complete response were collected. The group that maintained complete response and the group that experienced recurrence were compared, and the risk factors affecting recurrence were evaluated by logistic regression analysis.

Results

The complete response rate was 24.9% (73/289). Age, sex, tumor markers, maximum tumor diameter, multiplicity, presence of vascular invasion, and target radiation dose were significantly different between the complete response and noncomplete response groups. The recurrence rate after complete response was 38.4% (28/73), and 67.9% (19/28) of recurrences occurred by 8 months after complete response. Eight patients who underwent resection/transplantation after complete response experienced no recurrence. Multiple tumors and a lower target radiation dose were independent risk factors of recurrence after complete response in the multivariate logistic regression.

Conclusion

Hepatocellular carcinoma recurrence following complete response after radioembolization is not uncommon and frequently occurs within 1 year after complete response. Multiple tumors and a lower target radiation dose may be risk factors for recurrence.

Clinical, dosimetric, and reporting considerations for Y-90 glass microspheres in hepatocellular carcinoma: updated 2022 recommendations from an international multidisciplinary working group

PURPOSE

In light of recently published clinical reports and trials, the TheraSphere Global Dosimetry Steering Committee (DSC) reconvened to review new data and to update previously published clinical and dosimetric recommendations for the treatment of hepatocellular carcinoma (HCC).

METHODS

The TheraSphere Global DSC is comprised of health care providers across multiple disciplines involved in the treatment of HCC with yttrium-90 (Y-90) glass microsphere-based transarterial radioembolization (TARE). Literature published between January 2019 and September 2021 was reviewed, discussed, and adjudicated by the Delphi method. Recommendations included in this updated document incorporate both the results of the literature review and the expert opinion and experience of members of the committee.

RESULTS

Committee discussion and consensus led to the expansion of recommendations to apply to five common clinical scenarios in patients with HCC to support more individualized efficacious treatment with Y-90 glass microspheres. Existing clinical scenarios were updated to reflect recent developments in dosimetry approaches and broader treatment paradigms evolving for patients presenting with HCC.

CONCLUSION

Updated consensus recommendations are provided to guide clinical and dosimetric approaches for the use of Y-90 glass microsphere TARE in HCC, accounting for disease presentation, tumor biology, and treatment intent.

Study on the changes of CT texture parameters before and after HCC treatment in the efficacy evaluation and survival predication of patients with HCC

Objective

To investigate texture parameters of contrast-enhanced computed tomography (CT) images before and after transarterial chemoembolization (TACE) as a tool for assessing the therapeutic response and survival predication in hepatocellular carcinoma (HCC).

Materials and methods

Data of 77 HCC patients who underwent three-phase dynamic contrast-enhanced CT examination within 4 weeks before and 4–8 weeks after TACE were collected and efficacy evaluation was performed according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) standard. The remission group consisted of 31 patients (12 with complete remission+19 with partial remission), while the non-remission group consisted of 46 patients (27 with stable disease+19 with progressive disease). Full-volume manual delineation of the region of interest (ROI) and texture analysis of the ROI were performed on the CT images using FireVoxel software. Changes in the 48 texture parameters from three-phase CT images before and after TACE were calculated and compared between the two groups. The receiver operating characteristic (ROC) curve and the areas under the curve (AUC) were used to analyze the diagnostic performance of texture parameters. A multifactorial Cox model was used for predicting survival. The C-indices of texture parameter difference values with predictive value, texture features model, and texture features combined with mRECIST in predicting OS were compared with those of mRECIST.

Results

A total of 41 changes in texture parameters were statistically significant between the remission and non-remission groups. The receiver operating characteristic (ROC) curve showed that the AUC of changes in the 90th percentile in the arterial phase was the largest at 0.842. When the cut-off value was 70.50, the Youden index was the largest (0.621), and the sensitivity and specificity were 0.710 and 0.911, respectively. Three changes in texture parameters were independent factors associated with patient survival, with a hazard of 0.173, 2.068, and 1.940, respectively. The C-index of the OS predicted by the texture features model was not statistically different from that of the mRECIST (0.695 vs. 0.668, p=0.493). While the C-indices of skewness in the portal venous phase combined with mRECIST (0.729, p=0.015), skewness in the delayed phase combined with mRECIST (0.715, p=0.044), and skewness in both two phases combined with mRECIST (0.728, p=0.017) were statistically different.

Conclusion

Changes in the texture parameters of CT images before and after TACE treatment can be used to obtain relevant grayscale histogram parameters for evaluating the early efficacy of TACE in HCC treatment. And the texture analysis combined with mRECIST may be superior to the mRECIST alone in predicting survival in HCC after TACE treatment.

Addition of Y-90 radioembolization increases tumor response and local disease control in hepatocellular carcinoma patients receiving sorafenib

PURPOSE

To compare the treatment response and progression-free survival (PFS) in advanced hepatocellular carcinoma (HCC) patients who received sorafenib treatment either alone or combined with radioembolization (RE).

METHODS

Follow-up images of the patients treated within a multicenter phase II trial (SORAMIC) were assessed by mRECIST. A total of 177 patients (73 combination arm [RE + sorafenib] and 104 sorafenib arm) were included in this post-hoc analysis. Response and progression characteristics were compared between treatment arms. Survival analyses were done to compare PFS and post-progression survival between treatment arms. Multivariate Cox regression analysis was used to compare survival with factors known to influence PFS in patients with HCC.

RESULTS

The combination arm had significantly higher objective response rate (61.6% vs. 29.8%, p < 0.001), complete response rate (13.7% vs. 3.8%, p = 0.022), and a trend for higher disease control rate (79.2% vs. 72.1%, p = 0.075). Progression was encountered in 116 (65.5%) patients and was more common in the sorafenib arm (75% vs. 52.0%, p = 0.001). PFS (median 8.9 vs. 5.4 months, p = 0.022) and hepatic PFS were significantly better in the combination arm (9.0 vs. 5.7 months, p = 0.014). Multivariate analysis confirmed the treatment arm as an independent predictor of PFS.

CONCLUSION

In advanced HCC patients receiving sorafenib, combination with RE has an additive anticancer effect on sorafenib treatment resulting in a higher and longer tumor response. However, the enhanced response did not translate into prolonged survival. Better patient selection and superselective treatment could improve outcomes after combination therapy.

Selective internal radiation therapy (SIRT) for hepatocellular carcinoma (HCC): informing clinical practice for multidisciplinary teams in England

Objective

Hepatocellular carcinoma (HCC) deaths are rising alarmingly. Many patients are unsuitable for available therapies. Poor response rates further hamper outcomes for those that are. Selective internal radiation therapy (SIRT) offers hope, although which patients benefit over standard approaches remains unclear.

Design/method

As a quality/service improvement, we audited consecutive patients treated with SIRT (2015-2020) by the Newcastle upon Tyne Hospitals National Health Service Foundation Trust HCC multidisciplinary team. Indications, Barcelona clinic liver cancer (BCLC) stage, treatment response, subsequent therapies and survival at 30 September 2021 were assessed.

Results

Fifty-one patients received SIRT. Thirty-day mortality was zero. Three months partial response, stable disease and progressive disease on imaging were 50%, 22% and 28%, respectively. Overall median survival was 21 months. There were four subgroups: (1) BCLC-B: HCC>7 cm too large for transarterial chemoembolisation (TACE) alone (n=21); (2) BCLC-B: HCC progressed post TACE (n=7); (3) BCLC-C: HCC with any combination of large tumour burden, branch portal vein thrombosis, non-hepatitis C virus aetiology (n=16); (4) BCLC-C: sorafenib inappropriate (n=7). In group 1, 5/21 (23.8%) of patients were downstaged to resection, 33% received subsequent medical therapies and median survival was >40 months. In BCLC-B patients treated second line (group 2), median survival was 14.2 months. In BCLC-C, median survival was 20.2 months for group 3 and 4.2 months for group 4.

Conclusion

SIRT outcomes for advanced HCC, often bridging patients with adverse predictive factors to subsequent surgery or medical therapies, were encouraging. A role after TACE or for BCLC-C patients requires further assessment.

Total Lesion Glycolysis on 18F-FDG PET/CT Is a Better Prognostic Factor Than Tumor Dose on 90Y PET/CT in Patients With Hepatocellular Carcinoma Treated With 90Y Transarterial Radioembolization

PURPOSE

This study aimed to evaluate the prognostic value of metabolic parameters on 18F-FDG PET/CT and tumor dose (TD) on posttreatment 90Y PET/CT in patients with hepatocellular carcinoma (HCC) who underwent 90Y transarterial radioembolization (TARE).

PATIENTS AND METHODS

Forty-seven HCC patients treated with 90Y TARE were retrospectively enrolled between January 2013 and October 2018. 18F-FDG PET/CT was performed before treatment. Maximum tumor SUV-to-mean normal liver SUV ratio (TLR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured for each patient. Voxel dosimetry was performed on 90Y PET/CT images to measure TD. The prognostic significance of metabolic parameters on 18F-FDG PET/CT, TD on 90Y PET/CT, and clinical factors for overall survival (OS) was evaluated. In addition, TD on 90Y PET/CT was analyzed in relation to the administered dose of 90Y-labeled microspheres and metabolic parameters on 18F-FDG PET/CT.

RESULTS

The median patient age was 57 years, and 37 patients (78.7%) were men. During the follow-up period, 25 patients (53.2%) died. In univariable analysis, Barcelona Clinic Liver Cancer stage C, Child-Pugh score, TD on 90Y PET/CT, TLR, MTV, and TLG were significant prognostic factors affecting OS (P < 0.05). In multivariable analysis, Barcelona Clinic Liver Cancer stage C and high TLG on 18F-FDG PET/CT were independent prognostic factors for OS (P < 0.05). The 1-year OS rates were 72.9% in patients with low TLG and 33.3% in patients with high TLG (P < 0.05). We also found that TD on 90Y PET/CT was not correlated with the administered dose of 90Y-labeled microspheres, but negatively correlated with TLG on pretreatment 18F-FDG PET/CT (P < 0.05).

CONCLUSIONS

TLG, a parameter incorporating both the degree of 18F-FDG uptake and amount of metabolically active tumor volume on pretreatment 18F-FDG PET/CT, is a better prognostic factor than TD on 90Y PET/CT for predicting OS in HCC patients treated with 90Y TARE.

Ytrrium-90 transarterial radioembolization in patients with gastrointestinal malignancies

Transarterial radioembolization (TARE) with yttrium-90 (Y90) is a promising alternative strategy to treat liver tumors and liver metastasis from colorectal cancer (CRC), as it selectively delivers radioactive isotopes to the tumor via the hepatic artery, sparring surrounding liver tissue. The landscape of TARE indications is constantly evolving. This strategy is considered for patients with hepatocellular carcinoma (HCC) with liver-confined disease and preserved liver function in whom neither TACE nor systemic therapy is possible. In patients with liver metastases from CRC, TARE is advised when other chemotherapeutic options have failed. Recent phase III trials have not succeeded to prove benefit in overall survival; however, it has helped to better understand the patients that may benefit from TARE based on subgroup analysis. New strategies and treatment combinations are being investigated in ongoing clinical trials. The aim of this review is to summarize the clinical applications of TARE in patients with gastrointestinal malignancies.

Evolution of Radioembolization in Treatment of Hepatocellular Carcinoma: A Pictorial Review

Transarterial radioembolization (TARE) with yttrium 90 has increasingly been performed to treat hepatocellular carcinoma (HCC). TARE was historically used as a palliative lobar therapy for patients with advanced HCC beyond surgical options, ablation, or transarterial chemoembolization, but recent advancements have led to its application across the Barcelona Clinic Liver Cancer staging paradigm. Newer techniques, termed radiation lobectomy and radiation segmentectomy, are being performed before liver resection to facilitate hypertrophy of the future liver remnant, before liver transplant to bridge or downstage to transplant, or as a definite curative treatment. Imaging assessment of therapeutic response to TARE is challenging as the intent of TARE is to deliver local high-dose radiation to tumors through microembolic microspheres, preserving blood flow to promote radiation injury to the tumor. Because of the microembolic nature, early imaging assessment after TARE cannot rely solely on changes in size. Knowledge of the evolving methods of TARE along with the tools to assess posttreatment imaging and response is essential to optimize TARE as a therapeutic option for patients with HCC. ^©RSNA, 2021.

The Modified Response Evaluation Criteria in Solid Tumors (RECIST) Yield a More Accurate Prognoses Than the RECIST 1.1 in Hepatocellular Carcinoma Treated with Transarterial Radioembolization

Background/Aims

The Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and modified RECIST (mRECIST) criteria have been used to assess treatment responses for hepatocellular carcinoma (HCC) patients. We investigated which criteria provides better survival predictions in HCC patients treated with transarterial radioembolization (TARE).

Methods

In total, 102 patients with unresectable intrahepatic HCC, who were treated with TARE between 2012 and 2017, were reviewed retrospectively. The treatment response after TARE was evaluated at 1, 3, and 6 months by the mRECIST and RECIST 1.1. Responders were defined as patients with complete or partial responses by each criterion.

Results

The median age of 83 men and 19 women was 64.3 years. The median alpha-fetoprotein and des-gamma-carboxy prothrombin levels were 37.1 ng/mL and 1,780.0 mAU/mL, respectively. The median maximal tumor size was 8.3 cm, and multiple tumors were observed in 36 patients (35.3%). During the follow-up period (median, 20.7 months), 21 patients (20.6%) died, with a mean survival time of 55.5 months. The cumulative survival rate was 96.1% at 6 months and 89.3% at 12 months. Responders, defined by the mRECIST at 1, 3, and 6 months after TARE, showed better survival outcomes than nonresponders (hazard ratio [HR]=5.736, p=0.008 at 1 month; HR=3.145, p=0.022 at 3 months, and HR=2.887, p=0.061 at 6 months). The survival rates of responders and nonresponders defined by the RECIST 1.1 were similar (all p>0.05).

Conclusions

Response evaluations that use the mRECIST provide more accurate prognoses than those that use the RECIST 1.1 in HCC patients treated with TARE.

Post-treatment CT LI-RADS categories: predictors of overall survival in hepatocellular carcinoma post bland transarterial embolization

PURPOSE

The LI-RADS Treatment Response (LR-TR) algorithm was introduced in 2017 to assist radiologists in assessing hepatocellular carcinoma (HCC) response following locoregional therapy. The objective of this study was to evaluate the associations between pre-treatment LI-RADS diagnostic categories, post-treatment LR-TR categories, and mRECIST response categories with overall survival (OS) of patients with HCC.

METHODS

This retrospective study included untreated patients with one or two lesions who underwent transarterial embolization with or without concomitant ablation from December 2003 to December 2017. Two radiologists (R1 and R2) reviewed pre- and post-treatment CT imaging. Associations between pre- and post-treatment variables, including post-treatment LR-TR categories (Viable, Equivocal, Nonviable), with OS were assessed using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

Eighty-five patients were included (median age = 71 years, range 50-87; 17 women). The median OS from first embolization was 43.92 months. Pre- and post-treatment tumor size, pre-treatment LR-TIV (compared with LR-5), and post-treatment LR-TR Viable (compared with LR-TR Nonviable) were associated with OS (p < 0.05 for all). Median OS was shorter for LR-TR Viable patients (R1, 25.64 months, 95% CI 18.58-35.70; R2, 26.43 months 95% CI 20.68-43.92) than for LR-TR Nonviable patients (64.21 months R1 and R2, 95% CI 42.71-92.45 and 36.30-94.09, respectively). mRECIST categories showed similar associations with OS. Inter-reader agreement was moderate for LI-RADS categories (κ = 0.57, 95% CI 0.35-0.78) and substantial for LR-TR categories (κ = 0.68, 95% CI 0.55-0.81).

CONCLUSIONS

LR-TR categories show a strong association with OS in HCC patients treated with transarterial embolization.

Predictors of Successful Yttrium-90 Radioembolization Bridging or Downstaging in Patients with Hepatocellular Carcinoma

PURPOSE

This study aims to identify clinical and imaging prognosticators associated with the successful bridging or downstaging to liver transplantation (LT) in patients undergoing Yttrium-90 radioembolization (Y90-RE) for hepatocellular carcinoma (HCC).

METHODS

Retrospectively, patients with Y90-RE naïve HCC who were candidates or potential candidates for LT and underwent Y90-RE were included. Patients were then divided into favorable (maintained or achieved Milan criteria (MC) eligibility) or unfavorable (lost eligibility or unchanged MC ineligibility) cohorts based on changes to their MC eligibility after Y90-RE. Penalized logistic regression analysis was performed to identify the significant baseline prognosticators.

RESULTS

Between 2013 and 2018, 135 patients underwent Y90-RE treatment. Among the 59 (42%) patients within MC, LT eligibility was maintained in 49 (83%) and lost in 10 (17%) patients. Within the 76 (56%) patients outside MC, eligibility was achieved in 32 (42%) and unchanged in 44 (58%). Among the 81 (60%) patients with a favorable response, 16 (20%) went on to receive LT. Analysis of the baseline characteristics revealed that lower Albumin-Bilirubin score, lower Child-Pugh class, lower Barcelona Clinic Liver Cancer stage, HCC diagnosis using dynamic contrast-enhanced imaging on CT or MRI, normal/higher albumin levels, decreased severity of tumor burden, left lobe HCC disease, and absence of HBV-associated cirrhosis, baseline abdominal pain, or fatigue were all associated with a higher likelihood of bridging or downstaging to LT eligibility (p's < 0.05).

CONCLUSION

Certain baseline clinical and tumor characteristics are associated with the successful bridging or downstaging of potential LT candidates with HCC undergoing Y90-RE.

18F-choline PET-computed tomography for the prediction of early treatment responses to transarterial radioembolization in patients with hepatocellular carcinoma

BACKGROUND

Transarterial radioembolization (TARE) is widely used for the treatment of hepatocellular carcinoma (HCC), but early treatment response can be very difficult to assess. The aim was to evaluate 18F-fluorocholine PET/computed tomography (CT) to assess the treatment response in patients with intermediate or locally advanced HCC.

METHODS

Between March 2019 and July 2020, nine HCC patients treated with TARE, who underwent PET/CT at baseline and 1 month after treatment, were enrolled. The maximum, mean (SUVmean), and peak (SUVpeak) standardized uptake value (SUV), SUV normalized by lean body mass (SUL), and total lesion glycolysis (TLG) were measured. Statistical analysis used the Mann-Whitney test to evaluate the differences in parameters between responders (partial and complete response) and nonresponders (stable or progressive disease) at the 6-month follow-up, according to the modified Response Evaluation Criteria in Solid Tumors.

RESULTS

Three patients were nonresponders (progressive disease and stable disease) and six were responders. Delta SUVmean, delta SUL, and delta TLG could predict an early response (P = 0.02, P = 0.04, and P = 0.02, respectively). None of the pre-therapeutic parameters were correlated with the response. Post-therapeutic SUL, SUVmean, TLG, and SUVpeak were also predictive of the response.

CONCLUSIONS

Our preliminary results showed that changes in certain metabolic parameters (from baseline PET to 1-month PET) are predictive of the response to TARE in HCC (Delta SUVmean, delta TLG, and delta SUL). The absence of post-treatment inflammation could lead to a better prediction than MRI evaluation. This study suggests that 1-month 18F-choline PET/CT could modify the clinical management predicting responders.Video Abstract: http://links.lww.com/NMC/A193.

Improved survival following transarterial radioembolization of infiltrative-appearance hepatocellular carcinoma

PURPOSE

Infiltrative-appearance hepatocellular carcinoma presents a challenge to clinicians as diagnostic criteria continue to evolve and evidence-based treatment guidelines have yet to be established. While transarterial radioembolization has shown efficacy in hepatocellular carcinoma, many studies exclude infiltrative-appearance HCC in their analysis. The purpose of this study was to describe imaging features of infiltrative-appearance hepatocellular carcinoma and evaluate effects of radioembolization on survival.

METHODS

In a retrospective review, infiltrative HCC patients treated from 2008 to 2017 were identified. Patients were divided into two groups: TARE versus systemic therapy/palliative care. Demographics, dates of diagnosis/expiry, albumin, international normalized ratio (INR), sodium, alpha-fetoprotein (AFP), creatinine, Child-Pugh class, model for end-stage liver disease (MELD) score, bilirubin, radiation dose and volume were collected. Patients with bilirubin > 3 were excluded. Mann-Whitney U test and Fisher's exact test assessed differences between groups. Kaplan-Meier survival and Cox proportional hazard analyses were performed.

RESULTS

Fifty-three patients were identified, 15 underwent TARE while 38 served as control. Mean age was 60, 43 patients were male. The mean overall survival was 16.2 months for the TARE group and 5.3 months for the control group (Log-rank p < 0.0001). Cox proportional regression analysis revealed significant associations between survival and albumin (HR 0.210, 0.052-0.839, p = 0.027), Child-Pugh class B (HR 0.196, 0.055-0.696, p = 0.012), sorafenib (HR 0.106, 0.031-0.360, p < 0.001), and number of affected liver lobes (HR 1.864, 1.387-2.506, p < 0.001).

CONCLUSIONS

Transarterial radioembolization for infiltrative HCC improves life expectancy compared to treatment with comfort measures or systemic therapy.

Liver Transplantation Following Yttrium-90 Radioembolization: 15-Year Experience in 207-Patient Cohort

BACKGROUND AND AIMS

Radioembolization (yttrium-90 [Y90]) is used in hepatocellular carcinoma (HCC) as a bridging as well as downstaging liver-directed therapy to curative liver transplantation (LT). In this study, we report long-term outcomes of LT for patients with HCC who were bridged/downstaged by Y90.

APPROACH AND RESULTS

Patients undergoing LT following Y90 between 2004 and 2018 were included, with staging by United Network for Organ Sharing (UNOS) tumor-node-metastasis criteria at baseline pre-Y90 and pre-LT. Post-Y90 toxicities were recorded. Histopathological data of HCC at explant were recorded. Long-term outcomes, including overall survival (OS), recurrence-free survival (RFS), disease-specific mortality (DSM), and time-to-recurrence, were reported. Time-to-endpoint analyses were estimated using Kaplan-Meier. Univariate and multivariate analyses were performed using a log-rank test and Cox proportional-hazards model, respectively. During the 15-year period, 207 patients underwent LT after Y90. OS from LT was 12.5 years, with a median time to LT of 7.5 months [interquartile range, 4.4-10.3]. A total of 169 patients were bridged, whereas 38 were downstaged to LT. Respectively, 94 (45%), 60 (29%), and 53 (26%) patients showed complete, extensive, and partial tumor necrosis on histopathology. Three-year, 5-year, and 10-year OS rates were 84%, 77%, and 60%, respectively. Twenty-four patients developed recurrence, with a median RFS of 120 (95% confidence interval, 69-150) months. DSM at 3, 5, and 10 years was 6%, 11%, and 16%, respectively. There were no differences in OS/RFS for patients who were bridged or downstaged. RFS was higher in patients with complete/extensive versus partial tumor necrosis (P < 0.0001). For patients with UNOS T2 treated during the study period, 5.2% dropped out because of disease progression.

CONCLUSIONS

Y90 is an effective treatment for HCC in the setting of bridging/downstaging to LT. Patients who achieved extensive or complete necrosis had better RFS, supporting the practice of neoadjuvant treatment before LT.

Selective Internal Radiation Therapy for Hepatocellular Carcinoma Across the Barcelona Clinic Liver Cancer Stages

BACKGROUND

Hepatocellular carcinoma (HCC) is the second most common lethal cancer, and there is a need for effective therapies. Selective internal radiation therapy (SIRT) has been increasingly used, but is not supported by guidelines due to a lack of solid evidence.

AIMS

Determine the efficacy and safety of SIRT in HCC across the Barcelona Clinic Liver Cancer (BCLC) stages A, B, and C.

METHODS

Consecutive patients that received SIRT between 2006 and 2016 at two centers in Canada were evaluated.

RESULTS

We analyzed 132 patients, 12 (9%), 62 (47%), and 58 (44%) belonged to BCLC stages A, B, and C; mean age was 61.2 (SD ± 9.2), and 89% were male. Median survival was 12.4 months (95% CI 9.6-16.6), and it was different across the stages: 59.7 (95% CI NA), 12.8 (95% CI 10.2-17.5), and 9.3 months (95% CI 5.9-11.8) in BCLC A, B, and C, respectively (p = 0.009). Independent factors associated with survival were previous HCC treatment (HR 2.01, 95% CI 1.23-3.27, p = 0.005), bi-lobar disease (HR 2.25, 95% CI 1.30-3.89, p = 0.003), ascites (HR 1.77, 95% CI 0.99-3.13, p = 0.05), neutrophil-to-lymphocyte ratio (HR 1.11, 95% CI 1.02-1.20, p = 0.01), Albumin-Bilirubin (ALBI) grade-3 (HR 2.69, 95% CI 1.22-5.92, p = 0.01), tumor thrombus (HR 2.95, 95% CI 1.65-5.24, p < 0.001), and disease control rate (HR 0.62, 95% CI 0.39-0.96, p = 0.03). Forty-four (33%) patients developed severe adverse events, and ALBI-3 was associated with higher risk of these events.

CONCLUSIONS

SIRT has the potential to be used across the BCLC stages in cases with preserved liver function. When using it as a rescue treatment, one should consider variables reflecting liver function, HCC extension, and systemic inflammation, which are associated with mortality.

A combination of sorafenib and radiotherapy reduces NF-κB activity and growth of hepatocellular carcinoma in an orthotopic mouse model

Hepatocellular carcinoma (HCC) is difficult to diagnose at an early stage, and its prognosis is generally poor. Sorafenib is the primary treatment for unresectable advanced HCC and targets multiple receptor tyrosine kinases. However, sorafenib only extends the average survival time by 3 months. This observation indicates that sorafenib may need to be combined with other treatments to further improve outcomes. We previously showed that combination of sorafenib with radiotherapy (RT) enhances tumor inhibition in subcutaneous HCC mouse models compared with monotherapy. The present study demonstrated that combining sorafenib and RT could suppress tumor growth in an orthotopic HCC model by regulating apoptosis and NF-κB-related pathways. Moreover, decreased numbers of visible liver tumors and a smaller percentage of spleen metastases were found in the combination group. A transient drop in body weight was initially observed after RT, but progressive recovery of body weight occurred. The current study showed that the combination of sorafenib and RT could be a safe strategy for HCC treatment.

Correlation and Agreement of Yttrium-90 Positron Emission Tomography/Computed Tomography with Ex Vivo Radioembolization Microsphere Deposition in the Rabbit VX2 Liver Tumor Model

PURPOSE

To demonstrate a stronger correlation and agreement of yttrium-90 (⁹⁰Y) positron emission tomography (PET)/computed tomography (CT) measurements with explant liver tumor dosing compared with the standard model (SM) for radioembolization.

MATERIALS AND METHODS

Hepatic VX2 tumors were implanted into New Zealand white rabbits, with growth confirmed by 7 T magnetic resonance imaging. Seventeen VX2 rabbits provided 33 analyzed tumors. Treatment volumes were calculated from manually drawn volumes of interest (VOI) with three-dimensional surface renderings. Radioembolization was performed with glass ⁹⁰Y microspheres. PET/CT imaging was completed with scatter and attenuation correction. Three-dimensional ellipsoid VOI were drawn to encompass tumors on fused images. Tumors and livers were then explanted for inductively coupled plasma (ICP)-optical emission spectroscopy (OES) analysis of microsphere content. ⁹⁰Y PET/CT and SM measurements were compared with reference standard ICP-OES measurements of tumor dosing with Pearson correlation and Bland-Altman analyses for agreement testing with and without adjustment for tumor necrosis.

RESULTS

The median infused activity was 33.3 MBq (range, 5.9-152.9). Tumor dose was significantly correlated with ⁹⁰Y PET/CT measurements (r = 0.903, P < .001) and SM estimates (r = 0.607, P < .001). Bland-Altman analyses showed that the SM tended to underestimate the tumor dosing by a mean of -8.5 Gy (CI, -26.3-9.3), and the degree of underestimation increased to a mean of -18.3 Gy (CI, -38.5-1.9) after the adjustment for tumor necrosis.

CONCLUSIONS

⁹⁰Y PET/CT estimates were strongly correlated and had better agreement with reference measurements of tumor dosing than SM estimates.

Prediction of overall survival in patients with hepatocellular carcinoma treated with Y-90 radioembolization by imaging response criteria

PURPOSE

To evaluate the potential of imaging criteria in predicting overall survival of patients with hepatocellular carcinoma (HCC) after a first transcatheter arterial yttrium-90 radioembolization (TARE) MATERIALS AND METHODS: From October 2013 to July 2017, 37 patients with HCC were retrospectively included. There were 34 men and 3 women with a mean age of 60.5±10.2 (SD) years (range: 32.7-78.9 years). Twenty-five patients (68%) were Barcelona Clinic Liver Cancer (BCLC) C and 12 (32%) were BCLC B. Twenty-four primary index tumors (65%) were>5cm. Three radiologists evaluated tumor response on pre- and 4-7 months post-TARE magnetic resonance imaging or computed tomography examinations, using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, modified RECIST (mRECIST), European Association for Study of the Liver (EASL), volumetric RECIST (vRECIST), quantitative EASL (qEASL) and the Liver Imaging Reporting and Data System treatment response algorithm. Kaplan-Meier survival curves were used to compare responders and non-responders for each criterion. Univariate and multivariate Cox proportional hazard ratio (HR) analysis were used to identify covariates associated with overall survival. Fleiss kappa test was used to assess interobserver agreement.

RESULTS

At multivariate analysis, RECIST 1.1 (HR: 0.26; 95% confidence interval [95% CI]: 0.09-0.75; P=0.01), mRECIST (HR: 0.22; 95% CI: 0.08-0.59; P=0.003), EASL (HR: 0.22; 95% CI: 0.07-0.63; P=0.005), and qEASL (HR: 0.30; 95% CI: 0.12-0.80; P=0.02) showed a significant difference in overall survival between responders and nonresponders. RECIST 1.1 had the highest interobserver reproducibility.

CONCLUSION

RECIST and mRECIST seem to be the best compromise between reproducibility and ability to predict overall survival in patients with HCC treated with TARE.

The efficacy, safety, and predictors of outcomes of transarterial radioembolization for hepatocellular carcinoma: a retrospective study

OBJECTIVES

Yttrium-90 transarterial radioembolization (TARE) is a safe, effective modality of locoregional therapy for intermediate and advanced-stage hepatocellular carcinoma (HCC). We aim to identify novel predictors of important outcomes of TARE therapy.

METHODS

A single-center retrospective study of 166 patients treated with TARE for HCC at Mayo Clinic Rochester between 2005-2015 and followed until December 2017. Multivariate logistic and stepwise regression analysis models were used to identify variables associated with overall survival (OS) and progression-free survival (PFS).

RESULTS

The median OS and the median PFS were12.9  (95% CI: 11.0-17.3), and 8 months (95% CI: 6-11), respectively. Macrovascular invasion (HR: 1.9 [1.3-2.8]), Child-Pugh score (CPS) B or C vs. A (HR: 1.8 [1.2-2.7]), Eastern Cooperative Oncology Group Performance status (ECOG-PS) 2 or 1 vs. 0 (HR: 1.6 [1.1-2.4]) and activity (A) of administered radiation dose (HR: 1.005[1.00-1.010), independently correlated with poorer OS. Infiltrative HCC (HR: 2.4 [1.3-4.5), macrovascular invasion (HR: 1.6 [1.1-2.7]), and high activity of administered radiation dose (HR: 1.005 [1.00-1.010) were associated with worse PFS.

CONCLUSION

In HCC patients treated with TARE; macrovascular invasion, the activity of radiation dose, CPS, ECOG-PS, and infiltrative HCC predict OS and PFS.

Transarterial Radioembolization for Hepatocellular Carcinoma and Hepatic Metastases: Clinical Aspects and Dosimetry Models

Transarterial radioembolization (TARE) with Yttrium-90 (⁹⁰Y) microspheres is a liver-directed therapy for primary and metastatic disease. This manuscript provides a review of the clinical literature on TARE indications and efficacy with overviews of patient-selection and toxicity. Current dosimetry models used in practice are safe, relatively simple, and easy for clinicians to use. Planning currently relies on the imperfect surrogate, ^99mTc macroaggregated albumin. Post-therapy quantitative imaging (⁹⁰Y SPECT/CT or ⁹⁰Y PET/CT) of microspheres can be used to calculate the macroscopic in vivo absorbed dose distribution. Similar to the evolution of other brachytherapy dose calculations, TARE is moving toward more patient-specific dosimetry that includes calculating and reporting nonuniform dose distributions throughout tumors and normal uninvolved liver.

The Treatment of Hepatocellular Carcinoma With Portal Vein Tumor Thrombosis

Hepatocellular carcinoma (HCC) is the sixth most common cancer and third leading cause of cancer-related death worldwide. HCC is also is a tumor with a distinct ability to invade and grow within the hepatic vasculature. Approximately 20% of patients with HCC have macrovascular invasion (MVI) at the time of diagnosis. MVI is associated with dismal prognosis, with median survival ranging from 2 to 5 months. Current staging systems designate MVI as advanced disease. Recent advances in multimodal approaches, including systemic therapies, radiation therapy, liver-directed therapies, and surgical approaches, in the treatment of HCC with MVI have rendered this disease process more treatable with improved outcomes and are discussed here.

The number of microspheres in Y90 radioembolization directly affects normal tissue radiation exposure

PURPOSE

In Y90 radioembolization, the number of microspheres infused varies by more than a factor of 20 over the shelf-life of the glass radioembolization device. We investigated the effect of the number of Y90 microspheres on normal liver tissue.

METHOD

Healthy pigs received lobar radioembolization with glass Y90 microspheres at 4, 8, 12, and 16 days post-calibration, representing a > 20× range in the number of microspheres deposited per milliliter in tissue. Animals were survived for 1-month post-treatment and the livers were explanted and scanned on a micro CT system to fully characterize the microscopic distribution of individual microspheres. A complete 3D microdosimetric evaluation of each liver was performed with a spatially correlated analysis of histopathologic effect.

RESULTS

Through whole-lobe microscopic identification of each microsphere, a consistent number of microspheres per sphere cluster was found at 4, 8, and 12 days postcalibration, despite an 8-fold increase in total microspheres infused from days 4 to 12. The additional microspheres instead resulted in more clusters formed and, therefore, a more homogeneous microscopic absorbed dose. The increased absorbed-dose homogeneity resulted in a greater volume fraction of the liver receiving a potentially toxic absorbed dose based on radiobiologic models. Histopathologic findings in the animals support a possible increase in normal liver toxicity in later treatments with more spheres (i.e., ≥ day 12) compared to early treatments with less spheres (i.e., ≤ day 8).

CONCLUSION

The microdosimetric evidence presented supports a recommendation of caution when treating large volumes (e.g., right lobe) using glass ⁹⁰Y microspheres at more than 8 days post-calibration, i.e., after "2nd week" Monday. The favorable normal tissue microscopic distribution and associated low toxicity of first week therapies may encourage opportunities for dose escalation with glass microspheres and could also be considered for patients with decreased hepatic reserve.

Feasibility and safety of liver transplantation or resection after transarterial radioembolization with Yttrium-90 for unresectable hepatocellular carcinoma

BACKGROUND

The benefit of transarterial radioembolization (TARE) in patients with unresectable hepatocellular carcinoma (HCC) is increasingly evidenced. However, data on outcome of liver transplantation or resection after TARE remain scarce. This study aimed to assess the safety and feasibility of surgery after TARE in patients with unresectable HCC.

METHODS

Patients exclusively undergoing TARE followed by either orthotopic liver transplantation (OLT) or liver resection (LR) for HCC between 2012 and 2016 were included. Primary outcomes were postoperative morbidity and mortality. Secondary outcomes were overall survival (OS) and response to TARE.

RESULTS

Among 349 patients with HCC treated with TARE, 32 (9%) underwent either OLT (n = 22) or LR (n = 10), which represent the study cohort. In this group, TARE induced decreased viable nodules (p < 0.001), an efficient downsizing (p < 0.001) as well as a significant downstaging based on BCLC classification (p < 0.001). Overall, major complications and mortality after surgery occurred in 5 (16%) and 1 (3%) patients, respectively. For the whole study cohort, OS was 47 months while survival rates at 1-, 3- and 5-years reached 97%, 86% and 86%, respectively.

DISCUSSION

Liver surgery after TARE is feasible and safe. This strategy allows to offer a curative treatment in a subset of patients with unresectable HCC.

Clinical and dosimetric considerations for Y90: recommendations from an international multidisciplinary working group

The TheraSphere Global Dosimetry Steering Committee was formed in 2017 by BTG International to review existing data and address gaps in knowledge related to dosimetry. This committee is comprised of health care providers with diverse areas of expertise and perspectives on radiation dosimetry. The goal of these recommendations is to optimize glass microspheres radiation therapy for hepatocellular carcinoma while accounting for variables including disease presentation, tumour vascularity, liver function, and curative/palliative intent. The recommendations aim to unify glass microsphere users behind standardized dosimetry methodology that is simple, reproducible and supported by clinical data, with the overarching goal of improving clinical outcomes and advancing the knowledge of dosimetry.

Technical Aspects and Practical Approach Toward Same-Day Y90 Radioembolization in the Management of Hepatocellular Carcinoma

Radioembolization with Yttrium-90 (Y90) has been proven safe and effective for the treatment of primary and secondary hepatic malignancies. Standard protocols have necessitated planning angiography with Technetium-99m macroaggregated albumin (Tc99m MAA) administration/scan typically 1-2 weeks prior to the radioembolization therapy. The intent of this practice is to ensure appropriate patient selection and treatment candidacy while also confirming best dosimetry approaches. At our center, we started performing "same-day Y90" in 2008; in a subset of international patients with travel hardship, we performed the planning and treatment procedures consecutively on the same day. In this article, we reveal our practical approach to treating patients on the same day as planning angiography. With more than 160 same-day procedures completed between 2008 and 2017, the safety and efficacy of such a paradigm has been established at our center. This approach is appealing to patients, their families, and referring physicians. Appropriate patient selection and proper preprocedure planning based on baseline imaging are key elements in successful same-day radioembolization treatments.

Radioembolization Super Survivors: Extended Survival in Non-operative Hepatocellular Carcinoma

PURPOSE

To identify baseline characteristics and long-term prognostic factors in non-transplant patients with unresectable hepatocellular carcinoma (HCC) who had prolonged survival after treatment with yttrium-90 radioembolization (Y90).

MATERIALS AND METHODS

Sixty-seven "Super Survivors" (defined as ≥ 3-year survival after Y90) were identified within our 1000-patient Y90 database (2003-2017). Baseline imaging and follow-up occurred at 1 month and every 3 months thereafter. Overall survival (OS) was calculated with Kaplan-Meier estimates with log-rank test in subgroups: Child-Pugh (CP) score, distribution of disease, portal vein thrombus (PVT), and technique (segmental vs lobar Y90).

RESULTS

Median age 69.5 years (range 45-94 years); 69% male; 60% solitary HCC; 79% unilobar disease; 12% PVT; 10% ascites; Barcelona Clinic Liver Cancer Stage A-54%/B-28%/C-16%/D-2%; CP A-70%/B-28%/C-2%. Longest baseline tumor diameter was 5.4 ± 4.0 cm (mean ± SD). All patients had an imaging response (either partial or complete response). Median OS was 67.5 months (95% CI 55.2-82.5). CP score and main PVT stratified median OS (p = 0.0007 and p = 0.0187, respectively). Beyond 3 years, segmental versus lobar Y90 was associated with improved OS with a median OS of 80.2 versus 46.7 months, respectively (p = 0.0024). Dosing > 200 Gy was not a significant predictor of improved OS.

CONCLUSIONS

Super Survivors spanning the BCLC staging system maintained durable OS after radioembolization that was stratified by the extent of underlying liver disease. The common variable among all patients was an imaging response. Segmental versus lobar Y90 may have a long-term associated OS benefit.

Response Assessment by Volumetric Iodine Uptake Measurement: Preliminary Experience in Patients with Intermediate-Advanced Hepatocellular Carcinoma Treated with Yttrium-90 Radioembolization

PURPOSE

To retrospectively compare early response to yttrium-90 radioembolization (Y90) according to volumetric iodine uptake (VIU) changes, Response Evaluation Criteria In Solid Tumor 1.1 (RECIST 1.1) and modified RECIST (mRECIST) in patients with intermediate-advanced hepatocellular carcinoma (HCC) and to explore their association with survival.

MATERIALS AND METHODS

Twenty-four patients treated with Y90 and evaluated with dual-energy computed tomography before and 6 weeks after treatment were included. VIU was measured on late arterial phase spectral images; 6-week VIU response was defined as: complete response (CR, absence of enhancing tumor), partial response (PR, ≥ 15% VIU reduction), progressive disease (PD, ≥ 10% VIU increase) and stable disease (criteria of CR/PR/PD not met). RECIST 1.1 and mRECIST were evaluated at 6 weeks and 6 months. Responders included CR and PR. Overall survival (OS) was evaluated by Kaplan-Meier analysis and compared by Cox regression analysis.

RESULTS

High intraobserver and interobserver agreements were observed in VIU measurements (k > 0.98). VIU identified a higher number of responders (18 patients, 75%), compared to RECIST 1.1 (12.5% at 6 weeks and 23.8% at 6 months) and mRECIST (29.2% at 6 weeks and 61.9% at 6 months). There was no significant correlation between OS and RECIST 1.1 (P = 0.45 at 6 weeks; P = 0.21 at 6 months) or mRECIST (P = 0.38 at 6 weeks; P = 0.79 at 6 months); median OS was significantly higher in VIU responders (17.2 months) compared to non-responders (7.4 months) (P = 0.0022; HR 8.85; 95% CI 1.29-88.1).

CONCLUSION

VIU is highly reproducible; as opposite to mRECIST and RECIST 1.1, early VIU response correlates with OS after Y90 in intermediate-advanced HCC patients.

The role of external beam radiotherapy in the treatment of hepatocellular cancer

Hepatocellular carcinoma (HCC) is increasing in incidence and mortality. Although the prognosis remains poor, long-term survival has improved from 3% in 1970 to an 18% 5-year survival rate today. This is likely because of the introduction of well tolerated, oral antiviral therapies for hepatitis C. Curative options for patients with HCC are often limited by underlying liver dysfunction/cirrhosis and medical comorbidities. Less than one-third of patients are candidates for surgery, which is the current gold standard for cure. Nonsurgical treatments include embolotherapies, percutaneous ablation, and ablative radiation. Technological advances in radiation delivery in the past several decades now allow for safe and effective ablative doses to the liver. Conformal techniques allow for both dose escalation to target volumes and normal tissue sparing. Multiple retrospective and prospective studies have demonstrated that hypofractionated image-guided radiation therapy, used as monotherapy or in combination with other liver-directed therapies, can provide excellent local control that is cost effective. Therefore, as the HCC treatment paradigm continues to evolve, ablative radiation treatment has moved from a palliative treatment to both a "bridge to transplant" and a definitive treatment.