Prevention and treatment of complications of selective internal radiation therapy: Expert guidance and systematic review.

Selective internal radiation therapy (or radioembolization) by intra-arterial injection of radioactive yttrium-90-loaded microspheres is increasingly used for the treatment of patients with liver metastases or primary liver cancer. The high-dose beta-radiation penetrates an average of only 2.5 mm from the source, thus limiting its effects to the site of delivery. However, the off-target diversion of yttrium-90 microspheres to tissues other than the tumor may lead to complications. The most prominent of these complications include radiation gastritis and gastrointestinal ulcers, cholecystitis, radiation pneumonitis, and radioembolization-induced liver disease, which may occur despite careful pretreatment planning. Thus, selective internal radiation therapy demands an expert multidisciplinary team approach in order to provide comprehensive care for patients. This review provides recommendations to multidisciplinary teams on the optimal medical processes in order to ensure the safe delivery of selective internal radiation therapy. Based on the best available published evidence and expert opinion, we recommend the most appropriate strategies for the prevention, early diagnosis, and management of potential radiation injury to the liver and to other organs. (Hepatology 2017;66:969-982).

Y90 Radioembolization Significantly Prolongs Time to Progression Compared With Chemoembolization in Patients With Hepatocellular Carcinoma.

BACKGROUND & AIMS: Conventional transarterial chemoembolization (cTACE) is used to treat patients with hepatocellular carcinoma (HCC). Radioembolization is a minimally invasive procedure that involves implantation of radioactive micron-sized particles loaded with yttrium-90 (Y90) inside the blood vessels that supply a tumor. We performed a randomized, phase 2 study to compare the effects of cTACE and Y90 radioembolization in patients with HCC. METHODS: From October 2009 through October 2015, we reviewed patients with HCC of all Barcelona Clinic Liver Cancer (BCLC) stages for eligibility. Of these, 179 patients with BCLC stages A or B met our enrollment criteria and were candidates for cTACE or Y90 therapy. Patients were assigned randomly to groups that received Y90 therapy (n = 24; 50% Child-Pugh A) or cTACE (n = 21; 71% Child-Pugh A). The primary outcome was time to progression (TTP), evaluated by intention-to-treat analysis. Secondary outcomes included safety, rate of response (based on tumor size and necrosis criteria), and Kaplan-Meier survival time. We performed inverse probability of censoring weighting and competing risk analyses. RESULTS: Patients in the Y90 radioembolization group had significant longer median TTP (>26 mo) than patients in the cTACE group (6.8 mo; P = .0012) (hazard ratio, 0.122; 95% confidence interval [CI], 0.027-0.557; P = .007). This was confirmed by competing risk and inverse probability of censoring weighting analyses accounting for transplantation or death. A significantly greater proportion of patients in the cTACE group developed diarrhea (21%) than in the Y90 group (0%; P = .031) or hypoalbuminemia (58% in the cTACE group vs 4% in the Y90 group; P < .001). Similar proportions of patients in each group had a response to therapy, marked by necrosis (74% in the cTACE group vs 87% in the Y90 group) (P = .433). The median survival time, censored to liver transplantation, was 17.7 months for the cTACE group (95% CI, 8.3-not calculable) vs 18.6 months for the Y90 group (95% CI, 7.4-32.5) (P = .99). CONCLUSIONS: In a randomized phase 2 study of patients with HCC of BCLC stages A or B, we found Y90 radioembolization to provide significantly longer TTP than cTACE. Y90 radioembolization provides better tumor control and could reduce drop-out from transplant waitlists. ClinicalTrials.gov no. NCT00956930.

Selective internal radiation therapy compared with sorafenib for hepatocellular carcinoma with portal vein thrombosis.

PURPOSE: Tumoural portal vein thrombosis (PVT) is a major prognostic factor in hepatocellular carcinoma (HCC). The efficacy of sorafenib, the only treatment approved at an advanced stage, is limited. Based on previous data, selective internal radiation therapy (SIRT), or (90)Y radioembolization, seems an interesting option. We aimed to compare both treatments in this population. METHODS: We retrospectively compared patients treated in two centres for HCC with tumoural PVT. We compared overall survival (OS) between patients treated with SIRT and patients treated with sorafenib. Analyses were performed before and after 1:1 matching with a propensity score for controlling indication bias, using a Cox proportional hazards model. RESULTS: A total of 151 patients were analysed, 34 patients treated with SIRT and 117 patients treated with sorafenib only. In the whole population, SIRT was associated with a higher median OS as compared with sorafenib: 18.8 vs 6.5 months (log-rank p < 0.001). There was an imbalance of baseline characteristics between patients treated by SIRT and sorafenib, which justified patient matching with use of a propensity score: 24 patients treated with SIRT could be matched with 24 patients treated with sorafenib. OS was estimated with a median of 26.2 vs 8.7 months in patients treated with SIRT vs sorafenib, respectively (log-rank p = 0.054). Before and after patient matching, the adjusted hazard ratio related to treatment by SIRT was estimated at 0.62 [95 % confidence interval (CI) 0.39-0.97] (p = 0.037) and 0.40 (95 % CI 0.19-0.82) (p = 0.013), respectively. CONCLUSION: SIRT seems more effective than sorafenib in patients presenting with HCC and tumoural PVT. This hypothesis is being tested in prospective randomized trials.

Pilot randomized trial of selective internal radiation therapy vs. chemoembolization in unresectable hepatocellular carcinoma.

BACKGROUND & AIMS: To compare selective internal radiation therapy (SIRT) with transarterial chemoembolization (TACE), the standard-of-care for intermediate-stage unresectable, hepatocellular carcinoma (HCC), as first-line treatment. METHODS: SIRTACE was an open-label multicenter randomized-controlled pilot study, which prospectively compared primarily safety and health-related quality of life (HRQoL) changes following TACE and SIRT. Patients with unresectable HCC, Child-Pugh ≤B7, ECOG performance status ≤2 and ≤5 liver lesions (≤20 cm total maximum diameter) without extrahepatic spread were randomized to receive either TACE (at 6-weekly intervals until tumour enhancement was not observed on MRI or disease progression) or single-session SIRT (yttrium-90 resin microspheres). RESULTS: Twenty-eight patients with BCLC stage A (32.1%), B (46.4%) or C (21.4%) received either a mean of 3.4 (median 2) TACE interventions (N = 15) or single SIRT (N = 13). Both treatments were well tolerated. Despite SIRT patients having significantly worse physical functioning at baseline, at week-12, neither treatment had a significantly different impact on HRQoL as measured by Functional Assessment of Cancer Therapy-Hepatobiliary total or its subscales. Both TACE and SIRT were effective for the local control of liver tumours. Best overall response-rate (RECIST 1.0) of target lesions were 13.3% and 30.8%, disease control rates were 73.3% and 76.9% for TACE and SIRT, respectively. Two patients in each group were down-staged for liver transplantation (N = 3) or radiofrequency ablation (N = 1). CONCLUSIONS: Single-session SIRT appeared to be as safe and had a similar impact on HRQoL as multiple sessions of TACE, suggesting that SIRT might be an alternative option for patients eligible for TACE.

Radioembolisation with yttrium‒90 microspheres versus sorafenib for treatment of advanced hepatocellular carcinoma (SARAH): study protocol for a randomised controlled trial.

BACKGROUND: Untreated advanced hepatocellular carcinoma (HCC) is linked to poor prognosis. While sorafenib is the current recommended treatment for advanced HCC, radioembolisation (RE; also called selective internal radiation therapy or SIRT) with yttrium-90 microspheres has shown efficacy in cohort studies. However, there are no head-to-head trials comparing radiation therapy with yttrium-90 microspheres and sorafenib in advanced HCC. The SARAH trial has been designed to compare the efficacy and safety of sorafenib therapy and RE using yttrium-90 resin microspheres (SIR-Spheres™; Sirtex Medical Limited, North Sydney, Australia) in patients with advanced HCC. Quality of life (QoL) and cost-effectiveness will also be compared between therapies. METHODS/DESIGN: SARAH is a prospective, randomised, controlled, open-label, multicentre trial comparing the efficacy of RE with sorafenib in the treatment of patients with advanced HCC. The trial aims to recruit adults with a life expectancy of >3 months, Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1, and: advanced HCC according to the Barcelona criteria (stage C) or recurrent HCC after surgical or thermoablative treatment who are not eligible for surgical resection, liver transplantation or thermal ablation; or two rounds of failed chemoembolisation. Patients will be randomised 1:1 to receive either RE or sorafenib 400 mg twice daily. All patients will be monitored for between 12 and 48 months following start of treatment. The primary endpoint of the SARAH trial is overall survival (OS). Secondary endpoints include: adverse events, progression-free survival at 6 months; tumour response rate; general or liver disease-specific QoL scores; and cost of each treatment strategy. Assuming an increase in median OS of 4 months with RE versus sorafenib therapy, randomising at least 400 patients (200 in each treatment arm) will be sufficient for 80% power and a bilateral alpha risk of 5%; therefore, 440 patients will be enrolled to allow for 10% loss of patients due to ineligibility. DISCUSSION: The SARAH trial is the first randomised head-to-head study to compare RE with sorafenib in advanced HCC, and will establish the potential role of RE in HCC treatment guidelines. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01482442, first received 28 November 2011.

Yttrium 90-ibritumomab tiuxetan plus rituximab maintenance as initial therapy for patients with high-tumor-burden follicular lymphoma: a Wisconsin Oncology Network study.

INTRODUCTION: Yttrium 90-ibritumomab tiuxetan (90Y-IT) radioimmunotherapy has proved to be effective in relapsed follicular lymphoma (FL). We conducted a clinical trial in which 90Y-IT followed by maintenance rituximab (MR) was evaluated as initial therapy for high-tumor-burden FL. METHODS: Eligible patients had histologically confirmed FL and met the GELF (Groupe d'Etude des Lymphomes Folliculaires) criteria for high tumor burden. All patients received a single dose of 90Y-IT. Patients with platelet counts of 150,000/mm³ or higher received 0.4 mCi/kg, and patients with platelet counts between 100,000/mm³ and 149,000/mm³ received 0.3 mCi/kg. At 6 months, patients without progressive disease (PD) received rituximab weekly for 4 weeks at a dose of 375 mg/m² (consolidation therapy), followed by MR consisting of the same dose every 3 months for a planned 5 years. RESULTS: From January 2005 through November 2007, a total of 16 patients were enrolled. The median age was 52 years (range, 37-75). The major toxicity from 90Y-IT was myelosuppression, with 88% and 31% of the patients experiencing grade 3 and grade 4 hematologic toxicity, respectively. The responses to 90Y-IT induction therapy were as follows: 7 patients with complete response/unconfirmed complete response (CR/Cru), 4 with partial response (PR), 3 with stable disease (SD), and 2 with progressive disease (PD). We identified 6 patients with early PD (range, 4-16 months) and 10 patients with prolonged remission (range, 37-101+ months). Compared with the patients who had prolonged remission, the patients who had early PD tended to have larger baseline nodal masses. The median progression-free survival (PFS) has not been reached after a median follow-up period of 48 months. The 3-year PFS and overall survival (OS) rates were 56% (95% CI, 37%-87%) and 93% (95% CI, 80%-100%), respectively. CONCLUSION: The overall response rate (ORR) to 90Y-IT was 69% in patients who had previously untreated, high-tumor-burden FL, which is lower than what is observed with contemporary rituximab/chemotherapy combinations. MR after 90Y-IT did convert all PRs to CRs. Alternative therapies should be considered for patients who have FL with large nodal masses (>9 cm), whereas very durable responses are possible in patients who have intermediate-size masses (>9 cm).

Individualized dosimetry-based activity reduction of 9°Y-DOTATOC prevents severe and rapid kidney function deterioration from peptide receptor radionuclide therapy.

PURPOSE: Assessment of kidney function evolution after (90)Y-DOTATOC peptide receptor radionuclide therapy (PRRT) with capped activity administration based on a 37-Gy threshold of biological effective dose (BED) to the kidney. METHODS: In a prospective phase II study, patients with metastasized neuroendocrine tumours were evaluated for therapy using 185 MBq (111)In-pentetreotide with amino acid coinfusion. Planar whole-body images were acquired at four time-points after injection and kidney volumes were measured using CT/MRI. BED to the kidneys was estimated using an extended BED formula and biexponential renal clearance. Based on published BED dose-toxicity relationships, we allowed a maximal kidney BED of 37 Gy; if the calculated BED exceeded 37 Gy, treatment activity was reduced accordingly. Kidney function was assessed at baseline and at 18 months, predominantly using (51)Cr-EDTA. The rate of renal function decline was expressed as annual glomerular filtration rate loss (aGFRL). RESULTS: Only 22 of 50 patients reached the 18-months time-point, with most missing patients having died due to disease progression. In the 22 patients who reached 18 months, no rapid kidney function deterioration was observed over the 18 months, aGFRL >33% was not seen, and only three patients showed an increase of one toxicity grade and one patient an increase of two grades. No significant correlations between kidney volume (p = 0.35), baseline GFR (p = 0.18), risk factors for renal function loss (p = 0.74) and aGFRL were observed. Among the 28 patients who did not reach 18 months, one developed grade 4 kidney toxicity at 15 months after PRRT. CONCLUSION: Prospective dosimetry using a 37 Gy BED as the threshold for kidney toxicity is a good guide for (90)Y-DOTATOC PRRT and is associated with a low risk of rapid renal function deterioration and evolution to severe nephrotoxicity.

Yttrium-90 radioembolization for hepatocellular carcinoma: what we know and what we need to know.

In spite of substantial progress in the management of hepatocellular carcinoma (HCC), suboptimal treatment results are frequently seen in the intermediate and advanced stages of HCC. The current staging system indicates that multinodular HCC without vascular invasion needs to be treated by transarterial chemoembolization (TACE) and HCC with vascular nvasion or distant metastasis is linked to sorafenib, an an-tiangiogenic therapy. Radioembolization with yttrium-90 ((90)Y) is a recently introduced liver-directed therapy employing a catheter-based approach. Growing data suggest that (90)Y radioembolization has a potent anticancer effect with negligible adverse events if appropriate pretreatment evaluations including dosimetry, calculation of lung shunt fraction and assessment of vascular anatomy are performed. Retrospective and small prospective studies have shown response rates and survival after (90)Y therapy which are comparable to TACE and sorafenib in the intermediate and advanced stages, respectively. Although a large sample size is necessary to compare the outcome between TACE and radioembolization in intermediate-stage HCC, selected populations, for whom TACE would not be effective, are candidates for testing the role of (90)Y radioembolization. A multidisciplinary, combined approach in advanced HCC using loco-regional therapy such as radioembolization and systemic therapy including sorafenib also has to be investigated.

Radioembolization in combination with systemic chemotherapy as first-line therapy for liver metastases from colorectal cancer.

PURPOSE: To report clinical experience with radioembolization (RE) plus systemic chemotherapy as a first-line treatment for liver metastases from colorectal cancer (CRC). MATERIALS AND METHODS: Clinical outcomes were evaluated retrospectively among 19 patients with unresectable liver metastases from CRC who had a good performance status and a low burden of extrahepatic disease (EHD) and were eligible for RE. Most (74%) had disease confined to the liver. Concurrent treatment with 5-fluorourail/leucovorin (n = 7) or 5-fluorourail/leucovorin/oxaliplatin (FOLFOX; n = 12) was started 3-4 days before single treatment with RE. RESULTS: Overall response rate according to the Response Evaluation Criteria in Solid Tumors was 84% (two complete responses and 14 partial responses). Median progression-free survival (PFS) time was 10.4 months and median overall survival (OS) time was 29.4 months. For patients with disease confined to the liver, PFS improved (10.7 mo vs 3.6 mo; P = .09), with significant prolongation of OS (median, 37.8 mo vs 13.4 mo; P = .03) compared with those who had EHD. Nine patients, including three long-term (> 3 y) survivors, remained alive after a median follow-up of 18.6 months. Serious treatment-related toxicities included febrile neutropenia with concurrent FOLFOX treatment, a perforated duodenal ulcer, and one death from hepatic toxicity. CONCLUSIONS: The present findings confirm the effectiveness of RE plus systemic chemotherapy for metastatic CRC. Patients with liver-confined disease derived the greatest benefit, with median survival times beyond 36 months. Larger datasets from ongoing phase III trials are needed to further define the safety and efficacy of RE in the first-line setting.

Radioembolization of hepatocellular carcinoma.

In this review paper, available data on radioembolization of unresectable hepatocellular carcinoma (HCC) using commercially available radiopharmaceuticals, respectively (131)I-Lipiodol, Therasphere (glass-microspheres) and SIRspheres (resin-microspheres) are reviewed. In the palliative setting, (131)I-Lipiodol was shown to yield response rates of 17-92% which in patients with portal vein thrombosis (PVT) translate into a survival benefit as evidenced by a phase III randomized trial. Furthermore, in terms of efficacy, (131)I-Lipiodol is as efficacious as trans-arterial chemoembolization (TACE) but far better tolerated. In the adjuvant setting, improved recurrence-free and overall survival when compared to surgery alone have been reported but these results warrant confirmation by randomized prospective trials. Similar to (131)I-Lipiodol, when administered in a palliative setting, radioembolization using (90)Y microspheres was proven effective for selected cases of non-resectable HCC and well tolerated. Available data suggest that Therasphere treatment outperforms TACE both in terms of response as in terms of event-free survival in unresectable HCC. However, this finding needs confirmation by randomized prospective trials. Therasphere treatment was also shown to limit progression of HCC allowing potential candidates for orthotopic liver transplantation (OLT) more time to wait for donor organs as well as to downstage the HCC disease to such an extent that patients that were initially not, as yet become eligible for OLT with a gain in survival. Finally, Therasphere was shown to be safe and efficacious in HCC patients presenting with PVT, reason for which approval was granted for this indication by the FDA.

[Radioimmunotherapy for non-Hodgkin lymphoma: historical development and current status]. / Radioinmunoterapia en los linfomas no Hodgkin: desarrollo histórico y estado actual.

Radioimmunotherapy treatment for lymphoma is a novel targeted therapeutic approach. Several years of development of radioimmunotherapeutic compounds came to fruition in February of 2002 when 90Y-ibritumomab tiuxetan (Zevalin, Y2B8) was approved in the USA and later in Europe, for the treatment of relapsed or refractory, low grade or transformed B-cell lymphoma in the USA. 90Y-ibritumomab tiuxetan utilizes a monoclonal anti-CD20 antibody to deliver beta-emitting yttrium-90 to the malignant B-cells. Clinical trials have demonstrated its efficacy, with observed clinical responses in the 80 % range. This product has become available in Europe, with simplified administration, for the treatment of relapsed follicular lymphoma. A similar anti-CD20 radiotherapeutic compound, 131I-tositumomab, was subsequently approved in the USA. Promising studies exploring expanded applications of radioimmunotherapy as consolidation, as part of transplant, or in other histologic types have been recently completed or are under way. Radioimmunotherapy has been shown to be an effective and clinically relevant complementary therapeutic approach for patients with lymphoma, bringing the Nuclear Medicine into lymphoma therapeutics.

A phase II study of [90Y] yttrium-capromab pendetide in the treatment of men with prostate cancer recurrence following radical prostatectomy.

There is currently no curative therapy for men who have disseminated prostate cancer following failed radical prostatectomy. The purpose of this trial was to investigate systemic radioimmunotherapy in these men. Eight patients with occult metastatic prostate cancer following radical prostatectomy as evidenced solely by a rising serum PSA and evidence of soft tissue lesions outside the prostatic fossa detected by an [111I]indiumcapromab pendetide scan received an infusion of 10 mg of capromab pendetide labeled with 9 mCi/m2 of [90Y]yttrium. Serum PSA was used to measure response rate. There were no complete or partial responses by PSA criteria. Significant unexpected bone marrow toxicity developed in the first 6 of 8 patients treated. The last two patients received co-infusion of edetate calcium disodium in an effort to decrease marrow suppression. In these two patients less marrow toxicity was seen. Repeat 111In-capromab pendetide scans were uninterpretable due to grossly altered whole-body biodistribution of the radioimmunoconjugate. Retrospective analysis of serial PSA values after closure of the study showed a decrease in the log slope PSA for seven of eight patients following radioimmunotherapy, with a statistically significant change in the mean log slope (p = 0.01). The clinical significance of this small but measurable change is uncertain. We conclude that radioimmunotherapy for occult metastatic prostate cancer using 90Y-capromab-pendetide at the dose described does not lower serum PSA, is associated with significant hematologic toxicity, and leads to complexation of the immunoconjugate following subsequent capromab pendetide infusion.

Intraperitoneally administered 90Y-labelled monoclonal antibodies as a third line of treatment in ovarian cancer. A phase 1-2 trial: problems encountered and possible solutions.

A phase 1-2 trial of 90Y-labelled monoclonal antibody, HMFG1 administered intraperitoneally to 30 patients with ovarian carcinoma is presented. The problems encountered with myelotoxicity are described, and the steps which have so far been taken to overcome this and to increase the dose of 90Y to an estimated tumouricidal level. Bone deposition of free 90Y limits the dose which can be administered without severe bone marrow toxicity. The intravenous use of a chelating agent, Ledclair (EDTA) has allowed the dose to be increased from 18 to 30 mCi without causing severe myelotoxicity. 90Y-DTPA MAb is an unstable immunoconjugate in vivo and in vitro. The use of a more stable linkage such as a macrocycle should enable the administered dose to be increased without increasing the amount of free 90Y which becomes available to be deposited in bone. This would be expected to reduce toxicity and increase therapeutic efficacy.