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

The Impact of Radiation Dose and Tumour Burden on Outcomes in Hepatocellular Carcinoma: 11-Year Experience in a 413-Patient Cohort Treated with Yttrium-90 Resin Microsphere Radioembolisation

Introduction

Transarterial radioembolisation (RE) using yttrium-90 (Y-90) microspheres is a widely used locoregional therapy for a broad spectrum of hepatocellular carcinoma (HCC) given its favourable safety profile. We evaluated the real-world outcomes of unresectable HCC treated with resin Y-90 RE and the relationship between tumour absorbed dose and subsequent curative therapy with survival.

Methods

Included were consecutive patients treated with Y-90 resin microspheres RE for unresectable HCC between January 2008 and May 2019 at the National Cancer Centre Singapore/Singapore General Hospital. The outcomes were stratified by tumour burden, distribution, presence of portal vein invasion (PVI) and liver function to improve prognostication.

Results

The median overall survival (OS) evaluated on 413 included patients was 20.9 months (95% CI: 18.2-24.0). More than half of the patients (214/413, 51.8%) had HCC beyond up-to-seven criteria, and 37.3% had portal vein invasion (154/413, 37.3%). Majority (71.7%) had dosimetry calculated based on the partition model. Patients who received ≥150 Gy to tumour had significantly better outcomes (OS 32.2 months, 95% CI: 18.3-46.4) than those who did not (OS 17.5 months, 95% CI: 13.7-22.7, p < 0.001). Seventy patients (17%) received curative therapies after tumour was downstaged by Y-90 RE and had better OS of 79.7 months (95% CI: 40.4 - NE) compared to those who did not receive curative therapies (OS 17.1 months; 95% CI: 13.5-20.4, p < 0.001). RE-induced liver injury was observed in 5.08% of the patients while 3.2% of the patients had possible radiation pneumonitis but none developed Grade 3-4 toxicity. For HCC without PVI, OS differed significantly with performance status, albumin-bilirubin grade, tumour distribution, and radiation dose; for HCC with PVI, Child-Pugh class and AFP were significant predictors of survival.

Conclusions

Treatment outcomes for unresectable HCC using Y-90 RE were favourable. Incorporating tumour burden and distribution improved prognostication. Patients who received tumour absorbed dose above 150 Gy had better OS. Patients who subsequently received curative therapies after being downstaged by Y-90 RE had remarkable clinical outcomes.

Neoadjuvant therapy for hepatocellular carcinoma-priming precision innovations to transform HCC treatment

Hepatocellular carcinoma (HCC) is increasing in prevalence globally, and cure remains limited with non-operative treatment. Surgical intervention, through resection or transplantation, offers a potential for cure for select patients. However, many patients present with advanced or unresectable disease, and recurrence rates remain high. Recent advances in systemic therapies, particularly immune checkpoint inhibitors, have demonstrated promise in treating unresectable HCC and as adjuvant therapy. Evidence from adjuvant trials highlights the synergistic potential of combined liver-directed and systemic therapies. These findings have ignited growing interest in neoadjuvant therapy across various scenarios: (1) as a bridging strategy while awaiting transplantation, (2) for downstaging disease to enable transplantation, (3) for converting unresectable disease to a resectable state, or (4) as neoadjuvant treatment in operable cases. Early-stage trials of neoadjuvant therapy in resectable HCC have reported promising outcomes. To realize the potential of neoadjuvant treatment for HCC, thoughtfully designed, adequately powered, multi-center clinical trials are essential.

Resin-Based Yttrium-90 Radioembolization as a Bridging or Downstaging Treatment to Liver Transplantation for Hepatocellular Carcinoma

PURPOSE

To evaluate the outcomes of resin-based yttrium-90 (90Y) transarterial radioembolization (TARE) for hepatocellular carcinoma (HCC) as a bridging or downstaging therapy to liver transplantation (LT) in terms of safety, tumor response, recurrence, and survival.

MATERIALS AND METHODS

A single-center retrospective analysis of patients with HCC treated with resin-based TARE as bridging or downstaging treatment to LT between January 2006 and April 2021 was performed. TARE-related liver toxicity was assessed. Imaging data were analyzed to assess tumor response. Histopathological analysis of explant livers was performed to assess HCC necrosis. Survival and bridging/downstaging success predictor analysis was performed.

RESULTS

Thirty-six patients underwent resin-based TARE with the intention to bridge (33%) or downstage (67%) to LT. Overall, 44% had ≥3 HCC lesions, and 53% had bilobar disease. Median largest tumor diameter was 3.4 cm. TARE was segmental, lobar, and bilobar in 20%, 36%, and 44% of cases, respectively. In total, 17% had Grade 3 bilirubin toxicities. The objective response rate per modified Response Evaluation Criteria in Solid Tumours was 72%. Patients meeting the United Network for Organ Sharing Downstaging criteria had higher chances of successful bridging/downstaging. Twenty-three patients were transplanted. Complete pathological response was noted in 30% of explant livers. Posttransplant tumor recurrence occurred in 26% within a median follow-up period of 1,710 days. Estimated 5-year progression-free, disease-specific, and overall survival rates after LT were 89%, 69%, and 89%, respectively. For the entire patient cohort, these survival rates were 87%, 53%, and 70%, respectively.

CONCLUSIONS

Resin-based 90Y TARE can be considered a valuable treatment option for bridging or downstaging patients with HCC to LT, including patients requiring lobar or bilobar TARE for extensive tumoral disease.

Transarterial Radioembolization Can Downstage Intermediate and Advanced Hepatocellular Carcinoma to Liver Transplantation

BACKGROUND

Transarterial radioembolization (TARE) is an effective treatment to control tumor growth and improve survival in hepatocellular carcinoma (HCC). The role of TARE in downstaging patients to liver transplantation (LT) is unclear. The aim of this study was to investigate the downstaging efficacy of TARE for intermediate and advanced HCC.

METHODS

Intention-to-treat analysis with multistate modeling was performed. Patients moved through 5 health states: (1) from TARE to listing, (2) from TARE to death without listing, (3) from listing to LT, (4) from listing to death without LT, and (5) from transplant to death. Factors affecting the chance of death after TARE were considered to stratify outcomes.

RESULTS

Two hundred fourteen patients underwent TARE. Of those, 43.9% had radiological response, 29.9% were listed, and 22.8% were transplanted. The probability of being alive without LT was 40.5% 1 y after TARE and 11.5% at 5 y. The chance of being listed was 9.4% at 1 y and 0.9% at 5 y. The probability of dying after TARE without LT was 38% at 1 y and 73% at 5 y. The overall survival of patients receiving LT was 61% at 5 y after transplant. Tumor beyond up-to-seven criteria, alfafetoprotein >400 ng/mL, and albumin-bilirubin ≥2 were associated with death. Three risk groups were associated with different response, chances of being listed, and receiving LT. Median survival was 3 y for low-risk, 1.9 y for intermediate-risk, and 9 mo for high-risk patients ( P  < 0.001).

CONCLUSIONS

In intermediate and advanced HCC, TARE allows for a 44% chance of response, 30% downstaging, and 23% probability of permitting LT. Patient's and tumor's characteristics allow for risk stratification and predict survival from TARE.

Radioembolization of HCC and secondary hepatic tumors: a comprehensive review

Transarterial radioembolization (TARE), also called Selective Internal Radiation Therapy (SIRT), has emerged as an effective locoregional therapy for primary and secondary hepatic tumors, utilizing yttrium-90 (Y90) microspheres and other agents such as holmium-166 and rhenium-188. TARE has various applications in the management of HCC across different BCLC stages. Radiation segmentectomy, which involves administering high doses of Y90 (>190 Gy), can be both curative and ablative, achieving complete necrosis of the tumor. In contrast, radiation lobectomy involves administering a lower dose of Y90 (80-120 Gy) as a neoadjuvant treatment modality to improve local control and induce future liver remnant (FLR) hypertrophy in patients who are planned to undergo surgery but have insufficient FLR. Modified radiation lobectomy combines both techniques and offers several advantages over portal vein embolization (PVE). Y90 is also used in downstaging HCC patients outside liver transplantation criteria, as well as bridging those awaiting liver transplantation (LT). Multiple studies and combined analyses were described to highlight the outcomes of TARE and compare it with other treatment modalities, including TACE and sorafenib. Additionally, the review delves into the efficacy and safety of radioembolization in managing metastatic colorectal cancer and other metastatic tumors to the liver. Recent studies have emphasized the role of personalized dosimetry for improved outcomes, and thus we described the different methods used for this purpose. Pretherapy imaging, estimating lung shunt, selection of therapeutic radionuclides, adverse effects, and cost-effectiveness were all discussed as well.

Using Voxel-Based Dosimetry to Evaluate Sphere Concentration and Tumor Dose in Hepatocellular Carcinoma Treated with Yttrium-90 Radiation Segmentectomy with Glass Microspheres

PURPOSE

To utilize voxel-based dosimetry following radiation segmentectomy (RS) to understand microsphere distribution and validate current literature regarding radiologic and pathologic outcomes.

MATERIALS AND METHODS

A retrospective, single-center analysis of patients with solitary hepatocellular carcinoma (N = 56) treated with yttrium-90 (90Y) RS with glass microspheres (Therasphere; Boston Scientific, Marlborough, Massachusetts) from 2020 to 2022 was performed. Posttreatment voxel-based dosimetry was evaluated using Mirada DBx Build 1.2.0 Simplicit90Y software (Boston Scientific) and utilized to calculate sphere concentration to tumor as well as D70 (minimum dose to 70% total tumor volume), D90, and D99. Time to progression (TTP), treatment response, and adverse events were studied.

RESULTS

Fifty-six solitary tumors were analyzed with a median tumor diameter of 3.4 cm (range, 1.2-6.8 cm) and median tumor absorbed dose of 732 Gy (range, 252-1,776 Gy). Median sphere activity (SA) at the time of delivery was 1,446 Bq (range, 417-2,621 Bq). Median tumor sphere concentration was 12,868 spheres/mL (range, 2,655-37,183 spheres/mL). Sphere concentration into tumor and normal tissue was inversely correlated with perfused treatment volume (R2 = 0.21 and R2 = 0.39, respectively). Of the 51 tumors with posttreatment imaging, objective response was noted in 49 patients (96%) and complete response in 42 patients (82%). The median TTP was not reached with a 2-year progression rate of 11%. Fifteen patients underwent liver transplant. Median tumor necrosis was 99% (range, 80%-100%). Lower tumor volumes and higher D99 were associated with complete pathologic necrosis (P < .001 and P = .022, respectively).

CONCLUSIONS

Voxel-based dosimetry following 90Y radioembolization can be utilized to account for sphere deposition and distribution into tumor. Ablative RS with high SA yields durable radiologic and pathologic outcomes.

Voxel-based tumor dose correlates to complete pathologic necrosis after transarterial radioembolization for hepatocellular carcinoma

PURPOSE

The transarterial radioembolization (TARE) dose is traditionally calculated using the single-compartment Medical Internal Radiation Dose (MIRD) formula. This study utilized voxel-based dosimetry to correlate tumor dose with explant pathology in order to identify dose thresholds that predicted response.

METHODS

All patients with HCC treated with TARE using yttrium-90 [90Y] glass microspheres at a single institution between January 2015 - June 2023 who underwent liver transplantation were eligible. The [90Y] distribution and dose-volume histograms were determined using Simplicity90 (Mirada Medical, Oxford UK) with a Bremsstrahlung SPECT/CT. A complete response was assigned if explant pathology showed complete necrosis and the patient had not undergone additional treatments to the same tumor after TARE. Logistic regression and receiver operator characteristic (ROC) curves were constructed to evaluate dose thresholds correlated with response.

RESULTS

Forty-one patients were included. Twenty-six (63%) met criteria for complete response. Dose to 95% (D95), 70% (D70), and 50% (D50) of the tumor volume were associated with likelihood of complete response by logistic regression (all p < 0.05). For lesions with complete response versus without, the median D95 was 813 versus 232 Gy, D70 was 1052 versus 315 Gy, and D50 was 1181 versus 369 Gy (all p < 0.01). A D95 > 719 Gy had the highest accuracy at 68% (58% sensitivity, 87% specificity) for predicting complete response. Median percent of tumor volume receiving at least 100 Gy (V100), 200 Gy (V200), 300 Gy (V300), and 400 Gy (V400) also differed by pathologic response: the median V100, V200, V300, and V400 was 100% versus 99%, 100% versus 97%, 100% versus 74%, and 100% versus 43% in the complete response versus non-complete response groups, respectively (all p < 0.05).

CONCLUSION

Voxel-based dosimetry was well-correlated with explant pathology. The D95 threshold had the highest accuracy, suggesting the D95 may be a relevant target for multi-compartment dosimetry.

Conversion Therapy to Transplant or Surgical Resection in Patients with Unresectable Hepatocellular Carcinoma Treated with Boosted Dose of Yttrium-90 Radiation Segmentectomy

BACKGROUND/OBJECTIVES

The aim of this study was to assess the efficacy of boosted dose yttrium-90 radioembolization (TARE) as a modality for conversion therapy to transplant or surgical resection in patients with unresectable hepatocellular carcinoma (HCC).

METHODS

In this single-center retrospective study, all patients with a diagnosis of HCC who were treated with boosted dose TARE (>190 Gy) between January 2013 and December 2023 were reviewed. Treatment response and decrease in tumor size were assessed with the RECIST v1.1 and mRECIST criteria. Milan and University of California, San Francisco (UCSF), criteria were used to determine transplant eligibility, and Barcelona Clinic Liver Cancer (BCLC) surgical resection recommendations were used to evaluate tumor resectability.

RESULTS

Thirty-eight patients with primary HCC who were treated with boosted dose TARE were retrospectively analyzed. The majority of the patients were Child-Pugh A (n = 35; 92.1%), BCLC C (n = 17; 44.7%), and ECOG performance status 0 (n = 25; 65.8%). The mean sum of the target lesions was 6.0 cm (standard deviation; SD = 4.0). The objective response rate (ORR) was 31.6% by RECIST and 84.2% by mRECIST. The disease control rate (DCR) was 94.7% by both RECIST and mRECIST. Among patients outside of Milan or UCSF, 13/25 (52.0%, Milan) and 9/19 (47.4%, UCSF) patients were successfully converted to within transplant criteria. Of patients who were initially unresectable, conversion was successful in 7/26 (26.9%) patients.

CONCLUSIONS

This study provides further real-world data demonstrating that boosted-dose TARE is an effective modality for conversion of patients with unresectable HCC to transplant or resection.

Ultrastable PLGA-Coated 177Lu-Microspheres for Radioembolization Therapy of Hepatocellular Carcinoma

Transarterial radioembolization (TARE) is a highly effective localized radionuclide therapy that has been successfully used to treat hepatocellular carcinoma (HCC). Extensive research has been conducted on the use of radioactive microspheres (MSs) in TARE, and the development of ideal radioactive MSs is crucial for clinical trials and patient treatment. This study presents the development of a radioactive MS for TARE of HCC. These MSs, referred to as 177Lu-MS@PLGA, consist of poly(lactic-co-glycolic acid) (PLGA) copolymer and radioactive silica MSs, labeled with 177Lu and then coated with PLGA. It has an extremely high level of radiostability. Cellular experiments have shown that it can cause DNA double-strand breaks, leading to cell death. In vivo radiostability of 177Lu-MS@PLGA is demonstrated by microSPECT/CT imaging. In addition, the antitumor study has shown that TARE of 177Lu-MS@PLGA can effectively restrain tumor growth without harmful side effects. Thus, 177Lu-MS@PLGA exhibits significant potential as a radioactive MS for the treatment of HCC.

Downstaging of Hepatocellular Carcinoma Before Liver Transplantation: Current Advances in Selection Criteria and Therapeutic Options

Liver transplantation (LT) is an ideal therapeutic option for selected patients with hepatocellular carcinoma (HCC). The selection criteria of HCC for LT have evolved in recent decades. Downstaging therapy is a promising strategy for patients with tumor burden beyond transplant criteria to increase the chance of receiving LT and improve posttransplant survival. Downstaging therapy is also a selection tool that refines the conventional selection criteria based on tumor morphology. Recently, the success of systemic treatment, including immune checkpoint inhibitors, antiangiogenic tyrosine kinase inhibitors, and VEGF inhibitors, in advanced HCC has prompted the discussion regarding the role of systemic therapies for HCC downstaging before transplantation. In this review, we aimed to summarize the current advances in selection criteria and therapeutic options of downstaging therapy for HCC before LT.

Selective internal radiation therapy for unresectable HCC: The SIRT downstaging study

BACKGROUND

Selective internal radiation therapy (SIRT) is recommended as a downstaging (DS) strategy for solitary unresectable HCC <8 cm. The aim of this study was to report the results of acquired experience in a tertiary center for all unresectable HCCs.

METHODS

We conducted a retrospective, observational study using data collected from consecutive patients undergoing SIRT between October 2013 and June 2020. DS was considered achieved when a curative treatment could be proposed 6 months after SIRT.

RESULTS

One hundred twenty-seven patients were included (male = 90%, 64 ± 11 y), of whom 112 (n = 88%) had cirrhosis. HCC was classified as BCLC stage C in 64 patients (50%), with a median diameter of 61 mm, an infiltrative pattern in 51 patients (40%), and portal vein invasion in 62 (49%) patients. Fifty patients (39%) achieved DS 6 months following SIRT, with 29 of them (23%) undergoing curative treatment in a median time of 4.3 months: 17 (13%) were transplanted, 11 (85%) had liver resection, and 1 patient had a radiofrequency ablation. The median overall survival of patients with or without DS was 51 versus 10 months, respectively (p < 0.001). In patients who achieved DS, progression-free survival was higher in patients who underwent surgery: 47 versus 11 months (p < 0.001). Four variables were independently associated with DS: age (OR: 0.96, 95% CI: [0.92, 0.99]; p = 0.032), baseline α-fetoprotein (OR: 1.00, 95% CI: [1.00, 1.00]; p = 0.034), HCC distribution (OR: 0.3, 95% CI: [0.11, 0.75]; p = 0.012), and ALBI grade (OR: 0.34. 95% CI: [0.14, 0.80]; p = 0.014).

CONCLUSIONS

These results suggest that SIRT in patients with unresectable HCC could be an effective treatment: DS was achieved for around 39% of the patients and more than half of these then underwent curative treatment.

Long-term Clinical Outcomes of Yttrium-90 Transarterial Radioembolization for Hepatocellular Carcinoma: A 5-Year Institutional Experience

RATIONALE AND OBJECTIVES

To examine the clinical outcomes of yttrium-90 (Y90) transarterial radioembolization (TARE) for primary hepatocellular carcinoma (HCC) through the evaluation of a 5-year institutional experience.

MATERIALS AND METHODS

This retrospective study evaluated 88 consecutive patients with primary HCC receiving Y90 TARE treatment at an academic medical center from 2017 to 2021. Disease distribution was bilobar in 60.2% of patients with an average lesion diameter of 5.0 ± 3.4 cm and Barcelona Clinic Liver Cancer stage B or C in 77% of the participants. Clinical outcomes were elucidated by examination of complications, liver function tests, biochemical response, and radiographic response. Objective response ratio (ORR) and progression-free survival (PFS) were also calculated.

RESULTS

The mean administered Y90 radiation dose was 127.8 ± 20.2 Gy. No significant complications or LFT elevations occurred post-therapy. Of the 73.9% of patients with α-fetoprotein-producing tumors, 67.8% experienced a complete or partial biochemical response 1 month post-treatment. The ORR was 83.3% on 6-month imaging and PFS was 9.6 ± 8.5 months. Functional outcomes (Eastern Cooperative Oncology Group) were maintained or improved in 79.6% and 76.1% of patients by 6 months and 1 year post-treatment, respectively. The mean survival was 14.7 ± 12.1 months. At 6 months post-treatment, 77.3% of patients were downstaged to or maintained Milan criteria, which was sustained for 74.4% and 70.0% of patients 1 year and 2 years after treatment, respectively.

CONCLUSION

Y90-TARE is a safe and effective therapy for primary HCC. Enduring outcomes further act as a realistic bridge to liver transplantation, with a majority of patients maintaining Milan criteria and preserving their functional status long term.

Locoregional Therapies for Hepatocellular Carcinoma prior to Liver Transplant: Comparative Pathologic Necrosis, Radiologic Response, and Recurrence

PURPOSE

To compare pathologic tumor necrosis rates after locoregional therapies (LRTs) for hepatocellular carcinoma (HCC) prior to liver transplantation and evaluate radiologic-pathologic correlation along with posttransplant HCC recurrence.

MATERIALS AND METHODS

Consecutive patients with solitary HCC bridged or downstaged with LRT from 2010 to 2022 were included. LRTs were transarterial chemoembolization (TACE), radioembolization (yttrium-90 [90Y]), ablation, and stereotactic body radiotherapy (SBRT). Upfront combination therapy options were TACE/ablation and TACE/SBRT. Subsequent therapy crossover due to local recurrence was allowed. Posttreatment imaging closest to the time of transplant, explant histopathologic necrosis, and tumor recurrence after transplant were reviewed.

RESULTS

Seventy-three patients met inclusion criteria, of whom 5 (7%) required downstaging. 90Y alone (n = 36) and multimodal therapy (pooled upfront combination and crossover therapy, n = 23) resulted in significantly greater pathologic necrosis compared with TACE alone (n = 14; P = .01). High dose 90Y radiation segmentectomy (≥190 Gy; n = 27) and TACE/ablation (n = 7) showed highest rates of complete pathologic necrosis (CPN)-63% (n = 17) and 71% (n = 5), respectively. Patients with CPN had a mean lesion size of 2.5 cm, compared with 3.2 cm without CPN (P = .04), irrespective of LRT modality. HCC recurrence was more common in patients without CPN (16%, 6/37) than in those with CPN (3%, 1/36; P = .11). Using Liver Imaging Reporting and Data System (LI-RADS), a nonviable imaging response was 75% sensitive and 57% specific for CPN.

CONCLUSIONS

Radiation segmentectomy and multimodal therapy significantly improved CPN rates compared with TACE alone. A LI-RADS treatment response of nonviable did not confidently predict CPN.

Applications of Yttrium-90 (90Y) in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, affecting millions of people worldwide. Due to the lack of systemic radiation therapy in hepatocellular carcinoma, researchers have been investigating the use of yttrium-90 (90Y) radioembolization for local-regional tumor control since the 1960s. With the development of glass and resin 90Y microspheres and the durable local control, good long-term efficacy, and equivalent tumor responsiveness and tolerability of 90Y-selective internal irradiation compared with alternative therapies such as transarterial chemoembolization (TACE) and sorafenib, 90Y radioembolization has gradually been applied in the treatment of hepatocellular carcinoma of all stages. In this article, we summarize the latest progress of 90Y in the treatment of hepatocellular carcinoma in terms of its principle, advantages, indications, contraindications, efficacy and adverse effects.

Transarterial Radioembolization (TARE) in Patients with Hepatocellular Carcinoma: A Comparison of Palliative with Bridging-to-Transplant Concepts

We investigated transarterial radioembolization (TARE) as a palliative measure and bridging-to-transplant therapy in hepatocellular carcinoma (HCC) patients. A total of 167 patients (50 bridging, 117 palliative) with 245 TARE procedures were assessed. Fourteen patients underwent subsequent liver transplantation (LT). Patients undergoing LT exhibited significantly prolonged progression-free survival (PFS) compared to those with bridging-without-transplant (p = 0.033). No significant differences were observed between patients with bridging-without-transplant and palliative cases (p = 0.116). Median overall survival (OS) post-TARE was 16.6 months, with estimated OS rates at 6/12 months of 82.0%/60.5%, respectively. Patients who underwent LT demonstrated statistically significantly longer OS compared to those with bridging-without-transplant (p = 0.001). No marked outcome distinctions were found between bridging-without-transplant and palliative groups. The findings underscored the superiority of LT over alternative treatments. TARE served as an important component in non-LT scenarios, allowing for subsequent therapeutic options. The study reflected the highly variable and complex situations of patients with HCC, emphasizing the need for further investigations to define an optimal multimodal approach.

Lineage-specific regulation of PD-1 expression in early-stage hepatocellular carcinoma following 90yttrium transarterial radioembolization - Implications in treatment outcomes

BACKGROUND

Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related deaths in the world. Liver-directed therapies, including 90Yttrium (90Y) radioembolization, play an integral role in the management of HCC with excellent response rates. This has led to clinical trials of immunotherapy in combination with 90Y. Elevated PD-1 expression and lymphopenia were recently shown as risk factors for disease progression in early-stage HCC treated with liver-directed therapies. The aim of this study was to investigate PD-1 expression dynamics in bridge/downstage to transplant in HCC patients receiving first-cycle 90Y and evaluate the impact of these changes on response rates and time-to-progression (TTP).

METHODS

Patients with HCC receiving first-cycle 90Y as a bridge to liver transplantation (n = 99) were prospectively enrolled. Blood specimens were collected before 90Y and again during routine imagining follow-up to analyze PD-1 expression via flow cytometry. Complete and objective response rates (CR and ORR) were determined using mRECIST.

RESULTS

In 84/88 patients with available follow-up imaging, 83% had a localized ORR with 63% having localized CR. For overall response, 71% and 54% experienced ORR and CR, respectively. Post-90Y PD-1 upregulation in CD8 + associated with HCC progression and decreased TTP. Treatment with 90Y was associated with an anticipated significant post-treatment drop in lymphocytes (P < 0.001) that was independent of PD-1 expression for either CD4+ or CD8+ T cells (P = 0.751 and P = 0.375) and not associated with TTP risk. The change in lymphocytes was not correlated with PD-1 expression following treatment nor TTP.

CONCLUSIONS

Elevated PD-1 expression on peripheral T cells is associated with increased risk of HCC progression and shorter time to progression in bridging/downstaging to transplant HCC patients undergoing first-cycle 90Y. Treatment-induced lymphopenia was not associated with treatment response, or increased progression risk, suggesting this anticipated adverse event does not impact short-term HCC outcomes.

Ablation versus Radiation Segmentectomy for Small Liver Tumors

Hepatocellular carcinoma (HCC) is a liver malignancy that affects more than a million people worldwide with a complex multifactorial etiology. After the diagnosis of HCC is made, physicians establish management using the Barcelona Clinic Liver Cancer (BCLC) guidelines revolving around tumor stage, liver function, performance status, and patient preferences. According to recent updates to these guidelines, thermal ablation is the second-best curative option apart from surgical resection for small HCC (< 2 cm). While thermal ablation is standard of care, recent studies have suggested that radiation segmentectomy (RS) has similar outcomes, limited hepatotoxicity, and ultimately a cost-efficient approach. Although there is limited literature on RS, this article compares ablation techniques against radiation segmentectomy for small HCC tumors.

Direct comparison and reproducibility of two segmentation methods for multicompartment dosimetry: round robin study on radioembolization treatment planning in hepatocellular carcinoma

PURPOSE

Investigate reproducibility of two segmentation methods for multicompartment dosimetry, including normal tissue absorbed dose (NTAD) and tumour absorbed dose (TAD), in hepatocellular carcinoma patients treated with yttrium-90 (90Y) glass microspheres.

METHODS

TARGET was a retrospective investigation in 209 patients with < 10 tumours per lobe and at least one tumour ≥ 3 cm ± portal vein thrombosis. Dosimetry was compared using two distinct segmentation methods: anatomic (CT/MRI-based) and count threshold-based on pre-procedural 99mTc-MAA SPECT. In a round robin substudy in 20 patients with ≤ 5 unilobar tumours, the inter-observer reproducibility of eight reviewers was evaluated by computing reproducibility coefficient (RDC) of volume and absorbed dose for whole liver, whole liver normal tissue, perfused normal tissue, perfused liver, total perfused tumour, and target lesion. Intra-observer reproducibility was based on second assessments in 10 patients ≥ 2 weeks later.

RESULTS

99mTc-MAA segmentation calculated higher absorbed doses compared to anatomic segmentation (n = 209), 43.9% higher for TAD (95% limits of agreement [LoA]: - 49.0%, 306.2%) and 21.3% for NTAD (95% LoA: - 67.6%, 354.0%). For the round robin substudy (n = 20), inter-observer reproducibility was better for anatomic (RDC range: 1.17 to 3.53) than 99mTc-MAA SPECT segmentation (1.29 to 7.00) and similar between anatomic imaging modalities (CT: 1.09 to 3.56; MRI: 1.24 to 3.50). Inter-observer reproducibility was better for larger volumes. Perfused normal tissue volume RDC was 1.95 by anatomic and 3.19 by 99mTc-MAA SPECT, with corresponding absorbed dose RDC 1.46 and 1.75. Total perfused tumour volume RDC was higher, 2.92 for anatomic and 7.0 by 99mTc-MAA SPECT with corresponding absorbed dose RDC of 1.84 and 2.78. Intra-observer variability was lower for perfused NTAD (range: 14.3 to 19.7 Gy) than total perfused TAD (range: 42.8 to 121.4 Gy).

CONCLUSION

Anatomic segmentation-based dosimetry, versus 99mTc-MAA segmentation, results in lower absorbed doses with superior reproducibility. Higher volume compartments, such as normal tissue versus tumour, exhibit improved reproducibility.

TRIAL REGISTRATION

NCT03295006.

Understanding the role of radiologists in complex treatment decisions for patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver and represents a significant global health burden. Management of HCC can be challenging due to multiple factors, including variable expectations for treatment outcomes. Several treatment options are available, each with specific eligibility and ineligibility criteria, and are provided by a multidisciplinary team of specialists. Radiologists should be aware of the types of treatment options available, as well as the criteria guiding the development of individualized treatment plans. This awareness enables radiologists to contribute effectively to patient-centered multidisciplinary tumor boards for HCC and play a central role in reassessing care plans when the treatment response is deemed inadequate. This comprehensive review aims to equip radiologists with an overview of HCC staging systems, treatment options, and eligibility criteria. The review also discusses the significance of imaging in HCC diagnosis, treatment planning, and monitoring treatment response. Furthermore, we highlight the crucial branch points in the treatment decision-making process that depend on radiological interpretation.

Contemporary applications of Y90 for the treatment of hepatocellular carcinoma

Transarterial radioembolization (TARE) with yttrium-90 (90Y) microspheres has been widely adopted for the treatment of HCC. Recent advances in yttrium-90 (90Y) dosimetry have led to durable local responses. Radiation segmentectomy has become a viable alternative to thermal ablation for early-stage HCC (Barcelona Clinic Liver Cancer 0 and A) and has been commonly used as a bridge to transplant. TARE is also commonly used for downstaging to transplant using traditional lobar dosimetry and radiation segmentectomy techniques. Radiation lobectomy has a dual role in local tumor control and induction of contralateral liver lobe hypertrophy as a bridge to resection for patients with an inadequate future liver remnant. TARE continues to provide disease control for patients with limited vascular invasion and may be an alternative to systemic therapy for patients with localized advanced disease. The potential synergy between TARE and immunotherapy has been recognized, and prospective studies evaluating this combination are needed for patients with Barcelona Clinic Liver Cancer B and C HCC.

Alpha-Fetoprotein Response after First Transarterial Chemoembolization (TACE) and Complete Pathologic Response in Patients with Hepatocellular Cancer

Transarterial chemoembolization (TACE) is used as a bridging treatment in liver transplant candidates with hepatocellular carcinoma (HCC). Alpha-fetoprotein (AFP) is the main tumor marker used for HCC surveillance. The aim of this study was to assess the potential of using the AFP change after the first TACE in the prediction of complete tumor necrosis. The study comprised 101 patients with HCC who underwent liver transplantation (LT) after TACE in the period between January 2011 and December 2020. The ΔAFP was defined as the difference between the AFP value before the first TACE and AFP either before the second TACE or the LT. The receiver operator characteristics (ROC) curves were used to identify an optimal cut-off value. Complete tumor necrosis was found in 26.1% (18 of 69) and 6.3% (2 of 32) of patients with an initial AFP level under and over 100 ng/mL, respectively (p = 0.020). The optimal cut-off value of ΔAFP for the prediction of complete necrosis was a decline of ≥10.2 ng/mL and ≥340.5 ng/mL in the corresponding subgroups. Complete tumor necrosis rates were: 62.5% (5 of 8) in patients with an initial AFP < 100 ng/mL and decline of ≥10.2 ng/mL; 21.3% (13 of 61) in patients with an initial AFP < 100 ng/mL and decline of <10.2 ng/mL; 16.7% (2 of 12) in patients with an initial AFP > 100 ng/mL and decline of ≥340.5 ng/mL; and null in 20 patients with an initial AFP > 100 ng/mL and decline of <340.5 ng/mL, respectively (p = 0.003). The simple scoring system, based on the initial AFP and AFP decline after the first treatment, distinguished between a high, intermediate and low probability of complete necrosis, with an area under the ROC curve of 0.699 (95% confidence intervals 0.577 to 0.821, p = 0.001). Combining the initial AFP with its change after the first treatment enables early identification of the efficacy of TACE.

Are patients with hepatocellular carcinoma and portal vein tumour thrombosis candidates for liver transplantation?

In this debate, the authors consider whether patients with hepatocellular carcinoma (HCC) and portal vein tumour thrombosis are candidates for liver transplantation (LT). The argument for LT in this context is based on the premise that, following successful downstaging treatment, LT confers a much greater clinical benefit in terms of survival outcomes than the available alternative (palliative systemic therapy). A major argument against relates to limitations in the quality of evidence for LT in this setting - in relation to study design, as well as heterogeneity in patient characteristics and downstaging protocols. While acknowledging the superior outcomes offered by LT for patients with portal vein tumour thrombosis, the counterargument is that expected survival in such patients is still below accepted thresholds for LT and, indeed, the levels achieved for other patients who receive transplants beyond the Milan criteria. Based on the available evidence, it seems too early for consensus guidelines to recommend such an approach, however, it is hoped that with higher quality evidence and standardised downstaging protocols, LT may soon be more widely indicated, including for this population with high unmet clinical need.

Multiple Pretransplant Treatments for Patients Without Pathological Complete Response may Worsen Posttransplant Outcomes in Patients with Hepatocellular Carcinoma

BACKGROUND

Liver transplant (LT) candidates with hepatocellular carcinoma (HCC) often receive cancer treatment before transplant. We investigated the impact of pre-transplant treatment for HCC on the risk of posttransplant recurrence.

METHODS

Adult HCC patients with LT at our institution between 2013 and 2020 were included. The impact of pre-LT cancer treatments on the cumulative recurrence was evaluated, using the Gray and Fine-Gray methods adjusted for confounding factors. Outcomes were considered in two ways: 1) by pathologically complete response (pCR) status within patients received pre-LT treatment; and 2) within patients without pCR, grouped by pre-LT treatment as A) none; B) one treatment; C) multiple treatments.

RESULTS

The sample included 179 patients, of whom 151 (84%) received pretreatment and 42 (28% of treated) demonstrated pCR. Overall, 22 (12%) patients experienced recurrence. The 5-year cumulative post-LT recurrence rate was significantly lower in patients with pCR than those without pCR (4.8% vs. 19.2%, P = 0.03). In bivariable analyses, pCR significantly decreased risk of recurrence. Among the 137 patients without pCR (viable HCC in the explant), 28 (20%) had no pretreatment (A), 70 (52%) had one treatment (B), and 39 (20%) had multiple treatments (C). Patients in Group C had higher 5-year recurrence rates than those in A or B (39.6% vs. 8.2%, 6.5%, P = 0.004 and P < 0.001, respectively). In bivariable analyses, multiple treatments was significantly associated with recurrence.

CONCLUSIONS

pCR is a favorable prognostic factor after LT. When pCR was not achieved by pre-LT treatment, the number of treatments might be associated with post-LT oncological prognosis.

Emerging treatment strategies in hepatobiliary cancer

INTRODUCTION

There have been significant advances in the treatment of hepatobiliary cancers, especially for advanced-stage disease. However, data is limited for optimal therapy selection in the first line and sequencing of available options.

AREAS COVERED

This review covers the systemic treatment of hepatobiliary cancers with an emphasis on the advanced stage. The previously published and ongoing trials will be discussed to create an algorithm for the current practice and to give future perspectives on how the field could go forward.

EXPERT OPINION

While there is no standard-of-care option in the adjuvant treatment of hepatocellular cancer, capecitabine is the standard of care for biliary tract cancer. The efficacy of adjuvant gemcitabine and cisplatin and the added benefit of radiotherapy to chemotherapy are yet to be defined. For the advanced stage, immunotherapy-based combinations became the standard of care for both hepatocellular and biliary tract cancers. The molecularly targeted therapy has profoundly changed the second-line and later treatment for biliary tract cancers, while the optimal second-line treatment for advanced hepatocellular cancer is yet to be defined due to rapid advances in the first-line setting.

Liver Resection and Transplantation Following Yttrium-90 Radioembolization for Primary Malignant Liver Tumors: A 15-Year Single-Center Experience

Radioembolization (RE) may help local control and achieve tumor reduction while hypertrophies healthy liver and provides a test of time. For liver transplant (LT) candidates, it may attain downstaging for initially non-candidates and bridging during the waitlist.

METHODS

Patients diagnosed with HCC and ICC treated by RE with further liver resection (LR) or LT between 2005-2020 were included. All patients selected were discarded for the upfront surgical approach for not accomplishing oncological or surgical safety criteria after a multidisciplinary team assessment. Data for clinicopathological details, postoperative, and survival outcomes were retrospectively reviewed from a prospectively maintained database.

RESULTS

A total of 34 patients underwent surgery following RE (21 LR and 13 LT). Clavien-Dindo grade III-IV complications and mortality rates were 19.0% and 9.5% for LR and 7.7% and 0% for LT, respectively. After RE, for HCC and ICC patients in the LR group, 10-year OS rates were 57% and 60%, and 10-year DFS rates were 43.1% and 60%, respectively. For HCC patients in the LT group, 10-year OS and DFS rates from RE were 51.3% and 43.3%, respectively.

CONCLUSION

Liver resection after RE is safe and feasible with optimal short-term outcomes. Patients diagnosed with unresectable or high biological risk HCC or ICC, treated with RE, and rescued by LR may achieve optimal global and DFS rates. On the other hand, bridging or downstaging strategies to LT with RE in HCC patients show adequate recurrence rates as well as long-term survival.

Yttrium-90 Radioembolization as the Major Treatment of Hepatocellular Carcinoma

BACKGROUND

The purpose of this study was to assess the safety and efficacy of Yttrium-90 radioembolization using in unresectable hepatocellular carcinoma.

METHODS

From 2017 to 2021, 32 patients with unresectable hepatocellular carcinoma, with mean tumor diameter about 7cm (21 males, 11 females; median age, 57.5 years of age), treated with Yttrium-90 radioembolization using resin microspheres were reviewed at pre-Yttrium-90 and post-Yttrium-90 follow-up. Tumor response was assessed according to the modified Response Evaluation Criteria in Solid Tumors. Outcomes including overall survival and progression-free survival were reported.

RESULTS

Median follow-up was 18 months. At follow-up examinations at 3-, 6-, and 12-months follow-up, the overall survival rates were 94%, 87% and 59%, and the progression-free survival rates were 78%, 64% and 60%, respectively. Complete response, partial response, stable disease, and progressive disease were noted in 7 (21.9%), 14 (43.7%), 4 (12.5%), and 7 (21.9%) patients, respectively. The disease control rate was 78.1%, the objective response rate was 65.6%, and the successful downstage rate was 34.4% (11 of 32). Nine of thirty-two patients underwent resection or transplantation after Yttrium-90 radioembolization with 2-year overall survival being 100%. No serious adverse events occurred after Yttrium-90 treatment. Worse overall survival was related to the larger tumor, higher stage, Eastern Cooperative Oncology Group performance status, and Child-Pugh score. And worse progression-free survival was related to the higher tumor burden, and pre-Yttrium-90 serum α-fetoprotein level >100.

CONCLUSION

Yttrium-90 Radioembolization can control hepatocellular carcinoma well even in advanced diseases. Patients successfully downstaging/bridging to resection or transplantation have excellent overall survival.

Transarterial therapies in patients with hepatocellular carcinoma eligible for transarterial embolization: a US cost-effectiveness analysis

OBJECTIVES

To assess the cost-effectiveness of transarterial radioembolization (TARE) versus conventional transarterial chemoembolization (cTACE) and drug-eluting beads chemoembolization (DEE-TACE) for patients with unresectable early- to intermediate-stage hepatocellular carcinoma (HCC).

DESIGN

A cohort-based Markov model with a five-year time horizon was developed to evaluate the cost-effectiveness of the three embolization treatments. Upon entering the model, patients with HCC received either TARE or one of the two other embolization treatments. Patients remained in a "watch and wait" state for tumor downstaging that allowed them to move to health states such as liver transplant, resection, systemic therapies, or cure. Clinical input parameters were retrieved from the published literature, and where values could not be sourced, assumptions were made and validated by clinical experts. Health benefits were quantified using quality-adjusted life years (QALYs). Cost input parameters were obtained from various sources, including the Medicare Cost Report, IBM® Micromedex RED BOOK, and published literature.

RESULTS

At five years, TARE was found to be cost-saving (saving $15,779 per person compared to cTACE) and produced 0.33 more QALYs per person than cTACE. TARE cost $13,696 more but produced 0.33 more QALYs than DEE-TACE, with an incremental cost-effectiveness ratio of $41,474 per QALY gained at five years. After accounting for parameter uncertainty, the likelihood of TARE being cost-effective was at least 90% against all comparators at a cost-effectiveness threshold of $100,000 per QALY gained.

CONCLUSIONS

TARE produces more QALYs than cTACE and DEE-TACE, with a high probability of being cost-effective against both comparators.

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.

Long-term Outcomes of Patients with Hepatocellular Carcinoma Who Underwent Microwave Ablation after Downstaging with Transarterial Chemoembolization to Barcelona Clinic Liver Cancer Stage A

PURPOSE

To compare the clinical results of microwave ablation (MWA) between patients downstaged to Barcelona Clinic Liver Cancer (BCLC) Stage A with transarterial chemoembolization (TACE) and those initially classified as BCLC Stage A.

MATERIALS AND METHODS

From January 2012 to May 2017, 1,087 patients were reviewed retrospectively using propensity score matching (1:1): 86 patients underwent MWA as a curative treatment after downstaging to BCLC Stage A by TACE (downstaging group) and 86 patients initially classified as BCLC Stage A underwent MWA (control group). The overall survival (OS) and disease-free survival (DFS) between the 2 groups were compared.

RESULTS

The 1-, 3-, and 5-year OS rates were 95.3%, 79.1%, and 58.1%, respectively, in the downstaging group and 93.0%, 81.4%, and 61.6%, respectively, in the control group (hazard ratio [HR], 0.75; 95% CI, 0.50-1.13; P = .162). The 1-, 3-, and 5-year DFS rates were 80.2%, 50.0%, and 24.4%, respectively, in the downstaging group and 77.9%, 52.3%, and 27.9%, respectively, in the control group (HR, 1.08; 95% CI, 0.76-1.53; P = .678). No significant differences were found in OS and DFS.

CONCLUSIONS

The long-term prognosis in patients with HCC who underwent MWA after downstaging to BCLC Stage A using TACE was similar to that in patients with initial BCLC Stage A.

Yttrium-90 Radioembolization: Current Indications and Outcomes

BACKGROUND

Radioembolization (RE) with 90Yttrium (Y90) has generally been used to treat patients with advanced disease. Recent data suggest, however, that RE is also safe and feasible to treat patients with early or intermediate stage disease. We herein review the current evidence regarding the use of RE with Y90 for patients with HCC.

METHODS

A comprehensive review of the literature was performed using MEDLINE/PubMed and Web of Science databases with a search end date of August 1, 2022.

RESULTS

Patients with HCC are often treated according to the BCLC staging system. Among patients with early-stage HCC (BCLC A), intermediate-stage HCC (BCLC B), and advanced-stage HCC (BCLC C), RE with Y90 has demonstrated promising results with comparable overall survival, time to disease progression, and radiological response compared with other standard of care treatment modalities. Moreover, Y90 RE can be used as a downstaging treatment modality for patients with advanced HCC who have a disease burden that is initially outside LT criteria. Radiation lobectomy (RL) has been described as a treatment modality with the intent of treating the ipsilateral liver that harbors the HCC, while also causing compensatory hypertrophy of the future liver remnant (FLR).

CONCLUSION

While initially considered as a palliative option for HCC patients, Y90 RE has emerged as an important part of the multi-modality care of patients with HCC across a wide spectrum of clinical indications.

Recent Advances in Hepatocellular Carcinoma Treatment with Radionuclides

As the third leading cause of cancer death worldwide, hepatocellular carcinoma (HCC) is characterized by late detection, difficult diagnosis and treatment, rapid progression, and poor prognosis. Current treatments for liver cancer include surgical resection, radiofrequency ablation, liver transplantation, chemotherapy, external radiation therapy, and internal radionuclide therapy. Radionuclide therapy is the use of high-energy radiation emitted by radionuclides to eradicate tumor cells, thus achieving the therapeutic effect. Recently, with the continuous development of biomedical technology, the application of radionuclides in treatment of HCC has progressed steadily. This review focuses on three types of radionuclide-based treatment regimens, including transarterial radioembolization (TARE), radioactive seed implantation, and radioimmunotherapy. Their research progress and clinical applications are summarized. The advantages, limitations, and clinical potential of radionuclide treatment of HCC are discussed.

Role of interventional oncology in hepatocellular carcinoma: Future best practice beyond current guidelines

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths globally. Liver transplant remains the goal of curative treatment, but limited supply of organs decreases accessibility and prolongs waiting time to transplantation. Therefore, interventional oncology therapies have been used to treat the majority of HCC patients, including those awaiting transplant. The Barcelona Clinic Liver Cancer (BCLC) classification is the most widely used staging system in management of HCC that helps allocate treatments. Since its inception in 1999, it was updated for the fifth time in November 2021 and for the first time shaped by expert opinions outside the core BCLC group. The most recent version includes additional options for early-stage disease, substratifies intermediate disease into three groups, and lists alternates to Sorafenib that can double the expected survival of advanced-stage disease. The group also proposed a new BCLC staging schema for disease progression, and endorsed treatment stage migration (TSM) directly into the main staging and treatment algorithm. This article reviews the recent developments underlying the current BCLC guidelines and highlights ongoing research, particularly involving radioembolization, that will shape future best practice.

Segmental Yttrium-90 Radioembolization as an Initial Treatment for Solitary Unresectable HCC

Objectives To evaluate the objective response rate (ORR), time to progression (TTP), and overall survival (OS) in patients with unresectable solitary HCC less than 5 cm who were treated with 90Y glass microspheres infused at a segmental level.

Materials and Methods Single-institution retrospective study of 35 patients with unresectable HCC deemed not suitable for percutaneous ablation who underwent segmental transarterial radioembolization (TARE) treatment. Eligibility criteria included patients with solitary, unilobar, < 5 cm unresectable HCC lesions who underwent TARE as a primary treatment strategy between November 2012 and April 2020. Imaging follow-up was performed on each patient at 3-, 6-, and 12 months post-treatment. Local and the overall tumor response was evaluated using mRECIST criteria, and primary endpoints were ORR, TTP, and OS. Adverse events (AEs) were graded for severity using the Common Terminology Criteria for Adverse Events (CTCAE) v.5.0.

Statistical Analysis Patient demographics, baseline characteristics, and treatment characteristics were analyzed using descriptive statistics. Predictors of survival were analyzed with Cox proportional hazards regression. Kaplan–Meier analysis was used to evaluate OS.

Results Median tumor size was 3 cm (range: 1.0-4.8 cm) in the 35 patients studied, with 25.7% (9/35) being the Eastern Cooperative Oncology Group (ECOG) 0 and 62.9% (22/35) ECOG 1. Most patients (88.5%, 31/35) were of the Barcelona Clinic Liver Cancer (BCLC) stage C, with one patient each classified as BCLC-A and BCLC-0, respectively. For 34.2% (12/35), TARE functioned as a bridge to transplantation. Transplanted patients exhibited a median pathologic necrosis of 98% (IQR 7.5). Combined ORR for local and overall mRECIST at 12 months post-TARE was 94.3% and 85.7%, respectively. All patients had a mean local TTP of 11.9 months (CI: 2.7–21.0) and global TTP of 13.2 months (CI: 6.4–20.0). Among the 14.3% (5/35) of patients who experienced AEs following treatment, 80% (4/5) were Grade 1, one patient experienced a Grade 4, and all events resolved within 1 month of treatment. Total OS at 1 year was 97%, whereas patients who underwent OLT had an OS of 100%.

Conclusion Segmental TARE was a safe and effective treatment for solitary unresectable HCC less than 5 cm. When used as a bridge to transplant, explants showed near complete pathologic necrosis of treated lesions.

Microwave ablation as bridging to liver transplant for patients with hepatocellular carcinoma: a single-center retrospective analysis

PURPOSE

To evaluate the efficacy and safety of microwave (MW) ablation as first-line locoregional therapy (LRT) for bridging patients with hepatocellular carcinoma (HCC) to liver transplant.

MATERIALS AND METHODS

This retrospective study evaluated 88 patients who received percutaneous MW ablation for 141 tumors as first-line LRT for HCC and listed for liver transplantation at a single medical center between 2011 and 2019. Overall survival rate status-post liver transplant, waitlist retention and disease progression were evaluated using Kaplan-Meier techniques.

RESULTS

Of 88 patients (72M, 16F, mean age 60 years, MELD=11.2) listed for transplant, median waitlist time was 9.4 months (IQR: 5.5 - 18.9). Seventy-one patients (80.7%) received transplant after median wait time of 8.5 months. Seventeen patients (19.3%) were removed from the waitlist, four (4.5%) due to tumors outside of the Milan criteria (HCC-specific dropout). No difference in tumor size or AFP was seen in transplanted vs. non-transplanted patients at time of ablation (2.1 vs. 2.1 cm and 34.4 vs. 34.7 ng/mL for transplanted vs. non-transplanted, respectively, p>0.05). Five of 88 patients (5.1%) experienced adverse events after ablation; however, all recovered. There were no cases of tract seeding. The local tumor progression (LTP) rate was 7.2%. The overall survival status-post liver transplant at 5-years was 76.7% and the disease-specific survival after LT was 89.6% with a median follow-up of 61 months for all patients.

CONCLUSION

MW ablation appears to be safe and effective for bridging patients with HCC to liver transplant without waitlist removal from seeding, adverse events, or local tumor progression.

Emerging curative-intent minimally-invasive therapies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common cause of liver malignancy and the fourth leading cause of cancer deaths universally. Cure can be achieved for early stage HCC, which is defined as 3 or fewer lesions less than or equal to 3 cm in the setting of Child-Pugh A or B and an ECOG of 0. Patients outside of these criteria who can be down-staged with loco-regional therapies to resection or liver transplantation (LT) also achieve curative outcomes. Traditionally, surgical resection, LT, and ablation are considered curative therapies for early HCC. However, results from recently conducted LEGACY study and DOSISPHERE trial demonstrate that transarterial radio-embolization has curative outcomes for early HCC, leading to its recent incorporation into the Barcelona clinic liver criteria guidelines for early HCC. This review is based on current evidence for curative-intent loco-regional therapies including radioembolization for early-stage HCC.

Outcomes in Elderly Patients Undergoing Liver Transplantation Compared with Liver-Directed Ablative Therapy in Early-Stage Hepatocellular Carcinoma

BACKGROUND

Orthotopic liver transplantation (OLT) is the accepted treatment in patients with unresectable, early-stage hepatocellular carcinoma (HCC) in the setting of cirrhosis. Due to increasing waitlist demand for OLT, determining optimal groups for transplant is critical. Elderly patients are known to have poorer postoperative outcomes. Considering the effectiveness of liver-directed therapies for HCC, we sought to determine whether elderly patients received survival benefit from OLT over liver-directed therapy alone.

STUDY DESIGN

The National Cancer Database participant use file was used to analyze data between 2004 and 2017. Only patients ≥70 years of age who received OLT or liver-directed therapy alone were included. Patients with alpha-fetoprotein >500 ng/mL or missing alpha-fetoprotein values were excluded. Baseline demographic variables, model for end-stage liver disease score, and overall survival from time of diagnosis were collected. Descriptive statistics, Kaplan-Meier survival, Cox proportional hazards model, and propensity score matching were used.

RESULTS

A total of 2,377 patients received ablative therapy alone, and 214 patients received OLT. Multivariable analysis and Kaplan-Meier showed that OLT conferred a significant survival benefit compared to liver-directed therapy alone. Age was also associated with a yearly 3% increase in risk of mortality. Propensity-matched analysis adjusting also demonstrated a significant survival benefit for elderly patients receiving OLT compared to liver-directed therapy alone.

CONCLUSION

Despite increased age and associated comorbidities being factors associated with poor outcomes, OLT confers a survival advantage compared to liver-directed ablative therapies alone in selected elderly patients with HCC. OLT should be offered in medically appropriate elderly patients with HCC.

Hepatocellular carcinoma radiation segmentectomy treatment intensification prior to liver transplantation increases rates of complete pathologic necrosis: an explant analysis of 75 tumors

PURPOSE

To verify the correlation between yttrium-90 glass microsphere radiation segmentectomy treatment intensification of hepatocellular carcinoma (HCC) and complete pathologic necrosis (CPN) at liver transplantation.

METHODS

A retrospective, single center, analysis of patients with HCC who received radiation segmentectomy prior to liver transplantation from 2016 to 2021 was performed. The tumor treatment intensification cohort (n = 38) was prescribed radiation segmentectomy as per response recommendations identified in a previously published baseline cohort study (n = 37). Treatment intensification and baseline cohort treatment parameters were compared for rates of CPN. Both cohorts were then combined for an overall analysis of treatment parameter correlation with CPN.

RESULTS

Sixty-three patients with a combined 75 tumors were analyzed. Specific activity, dose, and treatment activity were significantly higher in the treatment intensification cohort (all p < 0.01), while particles per cubic centimeter of treated liver were not. CPN was achieved in 76% (n = 29) of tumors in the treatment intensification cohort compared to 49% (n = 18) in the baseline cohort (p = 0.013). The combined cohort CPN rate was 63% (n = 47). ROC analysis showed that specific activity ≥ 327 Bq (AUC 0.75, p < 0.001), dose ≥ 446 Gy (AUC 0.69, p = 0.005), and treatment activity ≥ 2.55 Gbq (AUC 0.71, p = 0.002) were predictive of CPN. Multivariate logistic regression demonstrated that a specific activity ≥ 327 Bq was the sole independent predictor of CPN (p = 0.013).

CONCLUSION

Radiation segmentectomy treatment intensification for patients with HCC prior to liver transplantation increases rates of CPN. While dose strongly correlated with pathologic response, specific activity was the most significant independent radiation segmentectomy treatment parameter associated with CPN.

A microenvironment-responsive FePt probes for imaging-guided Fenton-enhanced radiotherapy of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) continues to be one of the most fatal malignancies with increasing morbidity, and potent therapeutics are urgently required given its insensitivity to traditional treatments. Here, we have developed a microenvironment-responsive FePt probes for the highly efficient Fenton-enhanced radiotherapy (FERT) of HCC. The selective release of Fe2+ in the acidic tumor microenvironment, but not in normal tissue, together with enhanced levels of hydrogen peroxide produced through the Pt radiosensitization effect, facilitates the generation of an enormous amount of hydroxyl radicals through the Fenton reaction, thereby extending the radiotherapeutic cascade and realizing a powerful therapeutic efficacy for HCC. Moreover, the "burst" release of Fe2+ contributes to the T2-to-T1 magnetic resonance imaging (MRI) switching effect, which informs the release of Fe2+, making imaging-guided cancer therapy feasible. This work not only breaks the bottleneck of traditional radiotherapy for HCC while minimally affecting normal tissues, but also provides a new strategy for FERT imaging guidance.

TARE in Hepatocellular Carcinoma: From the Right to the Left of BCLC

The Barcelona Clinic Liver Cancer (BCLC) system is the most commonly used staging system for hepatocellular carcinoma (HCC) in Western countries. BCLC aims to categorize patients into five stages with different prognoses and to allocate treatment according to these stages based on the best possible contemporary evidence. Transarterial radioembolization (TARE) has recently entered at the left of the BCLC algorithm (i.e., BCLC 0-A), mainly because of negative phase III trials in BCLC C stage. TARE has shown a steady increase in nationwide studies over the past 20 years and has even been adopted in some tertiary centers as the primary HCC treatment across all BCLC stages. We aimed to review the history of TARE in HCC, starting from advanced HCC and gradually expanding to earlier stages at the left of the BCLC system.

Role of Pretransplant Treatments for Patients with Hepatocellular Carcinoma Waiting for Liver Transplantation

Simple Summary

Hepatocellular carcinoma (HCC) is the fifth most common cancer in men worldwide and the second leading cause of cancer death. Liver transplantation (LT) is one of the treatment options for patients with HCC. Recently, there have been many reports of the usefulness of locoregional therapy, such as transarterial chemoembolization and radiofrequency ablation, for HCC as pretreatment before LT. In Western countries, locoregional therapy is used to bridge until transplantation to prevent drop-outs from the waiting list or for downstaging to treat patients with advanced HCC who initially exceed the criteria for LT. With the progress of locoregional therapy, new reports on the effects of bridging and downstaging locoregional therapy as pretransplant treatment are increasing in number.

Abstract

Recently, there have been many reports of the usefulness of locoregional therapy such as transarterial chemoembolization and radiofrequency ablation for hepatocellular carcinoma (HCC) as pretreatment before liver transplantation (LT). Locoregional therapy is performed with curative intent in Japan, where living donor LT constitutes the majority of LT due to the critical shortage of deceased donors. However, in Western countries, where deceased donor LT is the main procedure, LT is indicated for early-stage HCC regardless of liver functional reserve, and locoregional therapy is used for bridging until transplantation to prevent drop-outs from the waiting list or for downstaging to treat patients with advanced HCC who initially exceed the criteria for LT. There are many reports of the effect of bridging and downstaging locoregional therapy before LT, and its indications and efficacy are becoming clear. Responses to locoregional therapy, such as changes in tumor markers, the avidity of FDG-PET, etc., are considered useful for successful bridging and downstaging. In this review, the effects of bridging and downstaging locoregional therapy as a pretransplant treatment on the results of transplantation are clarified, focusing on recent reports.

Neoadjuvant treatment strategies for hepatocellular carcinoma

The incidence of hepatocellular carcinoma (HCC) remains high globally. Surgical treatment is the best treatment for improving the prognosis of patients with HCC. Neoadjuvant therapy plays a key role in preventing tumor progression and even downstaging HCC. The liver transplantation rate and resectability rate have increased for neoadjuvant therapy. Neoadjuvant therapy is effective in different stages of HCC. In this review, we summarized the definition, methods, effects, indications and contraindications of neoadjuvant therapy in HCC, which have significance for guiding treatment.

Evaluating the Effectiveness of Yttrium-90 Glass Microspheres in the Treatment of Hepatocellular Carcinoma, Intrahepatic Cholangiocarcinoma, and Metastatic Colorectal Cancer in Practice: Protocol for the Prospective PROACTIF Phase IV Registry Study in France

PRIMARY OBJECTIVE

Recently, selective internal radiation therapy using yttrium-90 (Y90) glass microspheres (TheraSphere™) was approved for reimbursement by health authorities in France. The PROACTIF study aims to gather data on effectiveness, patient quality of life, and safety with use of Y90 glass microspheres in real-world clinical settings in France.

INCLUSION CRITERIA

Patient with a diagnosis of hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (iCC), and/or metastatic colorectal cancer (mCRC) who was treated with a dose of Y90 glass microspheres that has been reimbursed in France and who do not oppose use of their personal medical data.

EXCLUSION CRITERIA

If data collection is opposed, treatment is reimbursed but not administered, or treatment is administered but not reimbursed.

OUTCOME MEASURES

Primary outcome measures include overall survival from time of Y90 glass microsphere treatment and quality of life, as assessed using the Functional Assessment of Cancer Therapy- Hepatobiliary questionnaire.

ESTIMATED NUMBER OF PATIENTS TO BE INCLUDED

This is an open study and there is no set number of patients; 115 have already been enrolled.

PLANNED SUBGROUP ANALYSES

Analyses will be stratified by disease state (HCC, iCC, or mCRC). Subgroups to be analyzed include age group, unilobar/bilobar disease at baseline, Eastern Cooperative Oncology Group (ECOG) status at baseline, liver tumor burden at baseline, target lesion size, and standard versus multi-compartment personalized dosimetry treatment.

PLANNED RECRUITMENT AND OBSERVATION PERIOD

Recruitment includes patients who are prescribed and treated with a commercial vial of Y90 glass microspheres between 01 January 2019 and 31 December 2024.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04069468.

Locoregional Treatments for Bridging and Downstaging HCC to Liver Transplantation

Liver transplantation (LT) is the first-line treatment for patients diagnosed with unresectable early-stage hepatocellular carcinoma (HCC) in the setting of cirrhosis. It is well known that HCC patients within the Milan criteria (solitary tumour ≤ 5 cm or ≤3 tumours, each <3 cm) could undergo LT with excellent results. However, there is a growing tendency to enlarge inclusion criteria since the Milan criteria are nowadays considered too restrictive and may exclude patients who would benefit from LT. On the other hand, there is a persistent shortage of donor organs. In this scenario, there is consensus about the role of loco-regional therapy (LRT) during the waiting list to select patients who would benefit more from LT, reducing the risk of drop off from the waiting list as well as decreasing tumour dimension to meet acceptable criteria for LT. In this review, current evidence on the safety, efficacy and utility of LRTs as neoadjuvant therapies before LT are summarized.

Yttrium-90 Radioembolization for the Treatment of Solitary, Unresectable HCC: The LEGACY Study

BACKGROUND AND AIMS

Locoregional therapies, including yttrium-90 radioembolization, play an important role in the treatment of unresectable HCC. The aim of the LEGACY (Local radioEmbolization using Glass Microspheres for the Assessment of Tumor Control with Y-90) study was to evaluate objective response rate (ORR) and duration of response (DoR) in patients with solitary unresectable HCC treated with yttrium-90 glass microspheres.

APPROACH AND RESULTS

LEGACY is a multicenter, single-arm, retrospective study conducted at three sites that included all eligible, consecutive patients with HCC treated with radioembolization between 2014 and 2017. Eligibility criteria included solitary HCC ≤ 8 cm, Child-Pugh A cirrhosis, and Eastern Cooperative Oncology Group performance status 0-1. Primary endpoints were ORR and DoR based on modified Response Evaluation Criteria in Solid Tumors in the treated area (localized), as evaluated by blinded, independent, central review. Radioembolization was performed with intent of ablative-level dosimetry in a selective fashion when possible. Overall survival was evaluated using Kaplan-Meier and multivariate Cox proportional hazards. Among the 162 patients included, 60.5% were Eastern Cooperative Oncology Group 0, and the median tumor size was 2.7 cm (range: 1-8) according to blinded, independent, central review. Radioembolization served as neoadjuvant therapy for transplantation or resection in 21.0% (34 of 162) and 6.8% (11 of 162) of patients, respectively, and as primary treatment for all others. Median follow-up time was 29.9 months by reverse Kaplan-Meier. ORR (best response) was 88.3% (CI: 82.4-92.4), with 62.2% (CI: 54.1-69.8) exhibiting a DoR ≥ 6 months. Three-year overall survival was 86.6% for all patients and 92.8% for those neoadjuvant patients with resected or transplanted liver.

CONCLUSIONS

In this multicenter study of radioembolization, clinical meaningful response rates and prolonged DoR were observed in the treatment of unresectable, solitary HCC ≤ 8 cm.

Contemporary Algorithm for the Management of Hepatocellular Carcinoma in 2021: The Northwestern Approach

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and a major cause of cancer-related morbidity and mortality around the world. Frequently, concurrent liver dysfunction and variations in tumor burden make it difficult to design effective and standardized treatment pathways. Contemporary treatment guidelines designed for an era of personalized medicine should consider these features in a more clinically meaningful way to improve outcomes for patients across the HCC spectrum. Given the heterogeneity of HCC, we propose a detailed clinical algorithm for selecting optimal treatment using an evidence-based and practical approach, incorporating liver function, tumor burden, the extent of disease, and ultimate treatment intent, with the goal of individualizing clinical decision making.

Principles of Radioembolization

Radioembolization has become a mainstay therapy in the treatment of primary and secondary liver cancers. This article will specifically discuss a brief history of yttrium treatment as well as an overview of the physical properties of the currently available devices. A discussion of the mechanism of action will be followed by a discussion on patient selection for this treatment.

Review of Use of Y90 as a Bridge to Liver Resection and Transplantation in Hepatocellular Carcinoma

BACKGROUND

The incidence of hepatocellular carcinoma (HCC) has been rising, and 80% of HCCs are unresectable at the time of presentation. In recent years, Yttrium-90 (Y90) radioembolization has arisen as a potential tool to treat the primary HCC tumor while also inducing contralateral liver hypertrophy to increase future liver remnant volumes. The goal of this multidisciplinary review is to summarize the contemporary evidence on the safety, efficacy, and utility of Y90 as a bridge to liver resection and transplant in patients with HCC.

METHODS

A narrative review was conducted of the recent literature regarding the utilization of Y90 as a therapy prior to liver resection or transplant in patients with HCC. A specific emphasis was placed on articles published in the last 10 years.

RESULTS

Y90 radioembolization has demonstrated a high safety profile and increasing utility in bridging and downstaging patients with HCC who subsequently undergo liver resection or transplant. The continuous advancements in treatment strategies and radiation dosimetry have paved the way for the incorporation of Y90 in all stages of HCC with different intents, including downstaging and bridging.

CONCLUSIONS

Y90 radioembolization can be safely used in the HCC population to bridge patients to resection or transplantation, induce future liver remnant growth, and select for less aggressive tumor biology prior to surgery.

Reassessment of the lung dose limits for radioembolization

Radioembolization, also known as selective internal radiation therapy (SIRT), is an established treatment for the management of patients with unresectable liver tumors. Advances in liver dosimetry and new knowledge about tumor dose-response relationships have helped promote the well-tolerated use of higher prescribed doses, consequently transitioning radioembolization from palliative to curative therapy. Lung dosimetry, unfortunately, has not seen the same advances in dose calculation methodology and renewed consensus in dose limits as normal liver and tumor dosimetry. Therefore, the efficacy of curative radioembolization may be compromised in patients where the current lung dose calculations unnecessarily limit the administered activity. The field is thus at a stage where a systematic review and update of lung dose limits is necessary to advance the clinical practice of radioembolization. This work summarizes the historical context and literature for origins of the current lung dose limits following radioembolization, that is, the 25-year-old, single institution, small patient cohort series that helped establish the lung shunt fraction and dose limits. Newer clinical evidence based on larger patient cohorts that challenges the historical data on lung dose limits are then discussed. We conclude by revisiting the rationale for current lung dose limits and by proposing a staged approach to advance the field of lung dosimetry and thus the practice of radioembolization as a whole.