Internal radiation therapy for patients with primary or metastatic hepatic cancer

LI-RADS radiation-based treatment response algorithm for HCC: what to know and how to use it

Locoregional treatments (LRT) continue to advance for hepatocellular carcinoma (HCC). Selective internal radiation therapy (SIRT) or transarterial radioembolization (TARE) with radioactive 90 Yttrium (Y90) microspheres is currently widely accepted, and external beam and stereotactic body radiation (EBRT/SBRT) are increasingly used as LRT1-5. Assessment of treatment response after these radiation-based therapies can be challenging, given that the adjacent liver also undergoes treatment related changes, inflammatory changes occur, and there is a variable time for response to develop. In 2017, the liver imaging reporting and data system (LI-RADS) workgroup initially developed a single algorithm for the imaging assessment of treatment response encompassing all types of locoregional therapies, the LI-RADS treatment response (LR-TR) algorithm. Recognizing that response and imaging patterns differ between radiation and non-radiation based therapies, the LR-TR working group recently updated the algorithm to reflect the unique characteristics of tumor response for therapies involving radiation. This article aims to elucidate the changes in the new version of the LI-RADS TR, with a guide for algorithm utilization and illustration of expected and unexpected findings post liver directed therapies for HCC.

Functional hydrogels for hepatocellular carcinoma: therapy, imaging, and in vitro model

Hepatocellular carcinoma (HCC) is among the most common malignancies worldwide and is characterized by high rates of morbidity and mortality, posing a serious threat to human health. Interventional embolization therapy is the main treatment against middle- and late-stage liver cancer, but its efficacy is limited by the performance of embolism, hence the new embolic materials have provided hope to the inoperable patients. Especially, hydrogel materials with high embolization strength, appropriate viscosity, reliable security and multifunctionality are widely used as embolic materials, and can improve the efficacy of interventional therapy. In this review, we have described the status of research on hydrogels and challenges in the field of HCC therapy. First, various preparation methods of hydrogels through different cross-linking methods are introduced, then the functions of hydrogels related to HCC are summarized, including different HCC therapies, various imaging techniques, in vitro 3D models, and the shortcomings and prospects of the proposed applications are discussed in relation to HCC. We hope that this review is informative for readers interested in multifunctional hydrogels and will help researchers develop more novel embolic materials for interventional therapy of HCC.

Diagnosis, pathophysiology, and treatment of SIRT-induced gastroduodenal ulcers: A systematic literature review

BACKGROUND

Selective Internal Radiation Therapy (SIRT) is a therapeutic modality in patients with hepatocellular carcinoma or liver metastases. Complications due to SIRT-induced gastric ulcers are seen in less than 5% of patients but there is no consensus for management of this rare side effect. We conducted a systematic review to analyze the efficacy of medical treatment of SIRT-induced ulcers.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. We developed the research question following the population, intervention, comparison, outcome, and study design (PICOS) format. We identified studies and cases reporting patients with gastric and/or duodenal (=population) ulcers treated with medical therapy with proton pump inhibitor (PPI), antacid, or sucralfate, alone or in combination (=intervention). We did not require that studies include a control group. We included studies reporting the evaluation of the medical and/or surgical treatment (=outcomes).

RESULTS

Out of 219 articles, 29 articles were included, resulting in analysis of data for a total of 51 patients who had a SIRT-induced gastric and/or duodenal ulcer treated with medication, surgery, or both. Twenty-eight patients (55%) were reported to have SIRT-induced ulcers that improved after initiation of PPI, antacid, or sucralfate treatment (alone or in combination). Twenty-three patients (45%) were reported to be refractory to medical treatment and surgery was performed in 7 out of 23 patients (30%).

CONCLUSIONS

About 45% of SIRT-induced gastroduodenal ulcers are refractory to medical treatment with PPI, antacid, or sucralfate, alone or in combination. Surgery is an effective treatment in patients who are refractory to medical treatment and who have intense symptoms.

Preparation and characterization of inorganic radioactive holmium-166 microspheres for internal radionuclide therapy

Microspheres with high specific activities of radionuclides are very interesting for internal radiotherapy treatments. This work focuses on the formulation and characterization of inorganic microspheres with a high content of holmium and therefore a high specific radioactivity of holmium-166. Two novel formulations of inorganic microspheres were obtained by dispersing solid holmium acetylacetonate microspheres (Ho₂(AcAc)₃-ms) in NaH₂PO₄ or NaOH solutions followed by 2 h incubation at room temperature. By exchange of acetylacetonate with phosphate or hydroxyl ions, holmium phosphate microspheres (HoPO₄-ms) and holmium hydroxide microspheres (Ho(OH)₃-ms) were formed respectively. The inorganic microspheres had a significantly smaller diameter (28.5 ± 4.4 μm (HoPO₄-ms) and 25.1 ± 3.5 μm (Ho(OH)₃-ms)) than those of Ho₂(AcAc)₃-ms (32.6 ± 5.2 μm). The weight percentage of holmium-165 in the microspheres increased significantly from 47% (Ho₂(AcAc)₃-ms) to 55% (HoPO₄-ms) and 73% (Ho(OH)₃-ms). After preparation of both HoPO₄-ms and Ho(OH)₃-ms, the stable holmium-165 isotope was partly converted by neutron activation into radioactive holmium-166 to yield radioactive microspheres. High specific activities were achieved ranging from 21.7 to 59.9 MBq/mg (¹⁶⁶HoPO₄-ms) and from 28.8 to 79.9 MBq/mg (¹⁶⁶Ho(OH)₃-ms) depending on the neutron activation time. The structure of both microspheres was preserved up to neutron activations of 6 h in a thermal neutron flux of 4.72 × 10¹⁶ n m^-2 s^-1. After activation, both microspheres revealed excellent stability in administration fluids (saline and phosphate buffer) having less than 0.05% of holmium released after 72 h incubation. Finally, the hemocompatibility of these inorganic microspheres was evaluated and it was shown that the microspheres did cause neither hemolysis nor depletion or inhibition of the coagulation factors of the intrinsic blood coagulation pathway meaning that the microspheres have a good hemocompatibility. Overall, this work shows that radioactive inorganic microspheres with high specific activities of holmium-166 can be prepared which potentially can be used for internal radionuclide therapy.

Multimodality imaging-guided local injection of eccentric magnetic microcapsules with electromagnetically controlled drug release

BACKGROUND

In the past decade, trackable smart drug delivery systems have played important roles in the treatment of many diseases such as cancer because the drug carriers can be visualized through their distinct physical properties. However, it is still difficult to achieve precise drug delivery because such systems usually rely on a single imaging system.

AIM

This study aimed to present a novel type of multimodality imaging-guided strategy to visualize the drug carriers of eccentric magnetic microcapsule (EMM) designed for potential treatment of hepatocellular carcinoma (HCC).

METHOD AND RESULTS

The EMMs were prepared by using a three-phase microfluidic device. The as-prepared EMMs embedded with Fe₃O₄ nanoparticles are magnetic, with high density and acoustic impedance, allowing for visualization by magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US) imaging during local injection. The release of drug from these EMMs can be further controlled by an external electromagnetic field (EMF). As a proof of concept, we demonstrated the process of multimodality imaging to guide local injection and the controlled release of doxorubicin (DOX) from the EMMs in a phantom. We showed that the release rate of DOX was directly correlated to the strength of the EMF. In addition, we cocultured green fluorescent protein (GFP)-transfected HeLa cancer cells with the DOX-loaded EMMs and documented their apoptosis by DOX following the release triggered by EMF.

CONCLUSION

The results suggest that these EMMs serve both as contrast agents that can be visualized by multimodality imaging techniques and as smart drug delivery systems, with great potential for precision medicine.

Titanium phosphate glass microcarriers induce enhanced osteogenic cell proliferation and human mesenchymal stem cell protein expression

In this study, we have developed 50- to 100-µm-sized titanium phosphate glass microcarriers (denoted as Ti5) that show enhanced proliferation of human mesenchymal stem cells and MG63 osteosarcoma cells, as well as enhanced human mesenchymal stem cell expression of bone differentiation markers, in comparison with commercially available glass microspheres at all time points. We also demonstrate that these microcarriers provide superior human mesenchymal stem cell proliferation with conventional Dulbecco’s Modified Eagle medium than with a specially developed commercial stem cell medium. The microcarrier proliferative capacity is revealed by a 24-fold increase in MG63 cell numbers in spinner flask bioreactor studies performed over a 7-day period, versus only a 6-fold increase in control microspheres under the same conditions; the corresponding values of Ti5 and control microspheres under static culture are 8-fold and 7-fold, respectively. The capability of guided osteogenic differentiation is confirmed by ELISAs for bone morphogenetic protein-2 and osteopontin, which reveal significantly greater expression of these markers, especially osteopontin, by human mesenchymal stem cells on the Ti5 microspheres than on the control. Scanning electron microscopy and confocal laser scanning microscopy images reveal favorable MG63 and human mesenchymal stem cell adhesion on the Ti5 microsphere surfaces. Thus, the results demonstrate the suitability of the developed microspheres for use as microcarriers in bone tissue engineering applications.

Survival benefit of radioembolization for inoperable hepatocellular carcinoma using yttrium-90 microspheres

BACKGROUND AND AIM

Transarterial radioembolization with yttrium-90 microspheres is one treatment option for inoperable hepatocellular carcinoma. We compared the survival in a cohort of patients receiving radioembolization or no radioembolization.

METHODS

The data of 46 patients referred for radioembolization was retrospectively reviewed. The patient, tumor characteristics, and the survival were compared in the two groups. The independent predictors for survival were studied with multivariate analysis. The side-effects and the complication of radioembolization-induced liver disease was recorded.

RESULTS

Thirty patients received radioembolization; 16 patients did not. The two groups did not differ in the mean age, Child-Pugh classes, Barcelona Clinic of Liver Cancer (BCLC) stages, tumor types, sum of diameter of the two biggest tumors, and extent of portal vein invasion. Those with BCLC stage C tumor, with portal vein thrombus, or with less than three nodules had significantly longer survival after radioembolization. There was a trend of longer survival in patients with Child-Pugh A liver function, or with BCLC stage B tumor after radioembolization. The median survival was more than 31.9 months, 14.5 months, and 5.2 months in patients with BCLC stage A, B, and C tumors. The independent predictors for longer survival were Child-Pugh class, tumor diameter sum, BCLC stage, and receiving radioembolization. Grade 2 irradiation-induced gastritis occurred in three patients (10%). Radioembolization-induced liver disease occurred in four patients (13%).

CONCLUSIONS

Radioembolization may prolong survival for patients with inoperable hepatocellular carcinoma. Radioembolization-induced liver disease occurred and should be further studied.

Phase II trial of palliative radiotherapy for hepatocellular carcinoma and liver metastases

PURPOSE

To evaluate the feasibility and response of liver radiotherapy (RT) in improving symptoms and quality of life in patients with hepatocellular carcinoma (HCC) or liver metastases (LM).

PATIENTS AND METHODS

Eligible patients had HCC or LM, unsuitable for or refractory to standard therapies, with an index symptom of pain, abdominal discomfort, nausea, or fatigue. The Brief Pain Inventory (BPI), Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep), and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) were completed by patients at baseline and each follow-up. The primary outcome was the percentage of patients with a clinically significant change at 1 month in the BPI subscale of symptom on average in the past 24 hours. Secondary outcomes were improvement in other BPI subscales and at other time points, FACT-Hep and EORTC QLQ-C30 at each follow-up, and toxicity at 1 week.

RESULTS

Forty-one patients (30 men and 11 women) with HCC (n = 21) or LM (n = 20) were accrued. At 1 month, 48% had an improvement in symptom on average in the past 24 hours. Fifty-two percent of patients had improvement in symptom at its worst, 37% at its least, and 33% now. Improvements in the FACT-G and hepatobiliary subscale were seen in 23% and 29% of patients, respectively, at 1 month. There were also improvements in EORTC QLQ-C30 functional (range, 11% to 21%) and symptom (range, 11% to 50%) domains. One patient developed grade 3 nausea at 1 week.

CONCLUSION

Improvements in symptoms were observed at 1 month in a substantial proportion of patients. A phase III study of palliative liver RT is planned. [Corrected]

Radiation pneumonitis following yttrium-90 radioembolization: case report and literature review

Radiation-induced pneumonitis (RP) is a rare complication of radioembolization with yttrium-90 ((90)Y) microspheres. The present report describes a case of RP in a patient with liver metastases from a gastrointestinal stromal tumor after radioembolization with (90)Y glass microspheres. This patient developed clinical, functional, and radiographic findings consistent with RP, with near-complete pulmonary parenchymal recovery and no clinical evidence of relapse or progressive decline in pulmonary function over a 9-month period. As clinical use of radioembolization expands, rare adverse events such as RP may become more frequent. It is essential that interventional radiologists, radiation/medical oncologists, and nuclear medicine physicians recognize this potential complication.

Bioactive glasses as potential radioisotope vectors for in situ cancer therapy: investigating the structural effects of yttrium

The incorporation of yttrium in bioactive glasses (BGs) could lead to a new generation of radionuclide vectors for cancer therapy, with high biocompatibility, controlled biodegradability and the ability to enhance the growth of new healthy tissues after the treatment with radionuclides. It is essential to assess whether and to what extent yttrium incorporation affects the favourable properties of the BG matrix: ideally, one would like to combine the high surface reactivity typical of BGs with a slow release of radioactive yttrium. Molecular Dynamics simulations show that, compared to a BG composition with the same silica fraction, incorporation of yttrium results in two opposing effects on the glass durability: a more fragmented silicate network (leading to lower durability) and a stronger yttrium-mediated association between separate silicate fragments (leading to higher durability). The simulations also highlight a high site-selectivity and some clustering of yttrium cations, which are likely linked to the observed slow rate of yttrium released from related Y-BG compositions. Optimisation of yttrium BG compositions for radiotherapy applications thus depends on the delicate balance between these effects.

Meta-analysis of interstitial pneumonia in studies evaluating iodine-131-labeled lipiodol for hepatocellular carcinoma using exact likelihood approach

PURPOSE

Iodine-131-labeled lipiodol is currently licensed for unresectable hepatocellular carcinoma with portal thrombosis. It is thought to be well tolerated. Cases of interstitial pneumonia have been reported, but their frequency (≈2%) has not been well estimated. Quantifying adverse drug event frequency requires an appropriate statistical approach because standard methods are biased.

METHODS

To estimate the frequency of interstitial pneumonia in patients with hepatocellular carcinoma receiving iodine-131-labeled lipiodol, we conducted a systematic review of English articles using MEDLINE and EMBASE. All types of articles were considered except case reports. Primary outcome measure was symptomatic interstitial pneumonia based on investigators' judgment. All pooled analyses were based on a random effects meta-analysis model using an exact likelihood approach based on the binomial within-study distribution.

RESULTS

Ten studies, including 142 patients, used low activity per dose, ranging from 0.3 to 1.1 GBq. No respiratory adverse event was noticed in these studies. Eighteen studies, including 542 patients, evaluated higher activity per dose, around 2.2 GBq; 24 cases of interstitial pneumonia were reported in these studies. Estimated frequency of interstitial pneumonia was 1.6% (95%CI, 0.4-6.4%) after one high dose and 4.1% (95%CI, 1.0-16.0%) after two or more high doses.

CONCLUSIONS

The frequency of interstitial pneumonia appears higher and more precise than previously estimated. The risk appears to be related to the number of injections and the dose level per injection. Generalized linear mixed models using the exact binomial within-study distribution initially described to summarize data on diagnostic evaluation could be relevant for drug-related adverse reaction frequency assessment.

Iodine-131-lipiodol therapy in hepatic tumours

The incidence of hepatocellular carcinoma (HCC) is worldwide sharply on the rise and patients with advanced disease carry a poor prognosis. HCC is the sixth most common cancer and the third leading cause of cancer associated deaths in the world. Intra-arterially administered (131)I-Lipiodol is selectively retained by hepatocellular carcinomas, and has been used as a vehicle for delivery of therapeutic agents to these tumours. In this review we focus on the therapeutic indications, usefulness and methods of treatment with 131-Iodine Lipiodol. The effectiveness of (131)I-Lipiodol treatment is proven both in the treatment of HCC with portal thrombosis and also as an adjuvant to surgery after the resection of HCCs. It is at least as effective as chemoembolization and is tolerated much better. Severe liver dysfunction represents theoretic contraindication for radioembolization as well as for TACE. In such cases (131)I-Lipiodol is an alternative therapy option especially in tumours smaller than 6cm.

Preparation and complex characterization of silica holmium sol-gel monoliths

Amorphous, sol-gel derived SiO(2) are known to biocompatible and bioresorbable materials. Biodegradable and inert materials containing radioactive isotopes have potential application as delivery vehicles of the beta radiation to the cancer tumors inside the body. Incorporation of holmium in the sol-gel derived SiO(2) could lead to the formation of a biodegradable material which could be used as carrier biomaterial for the radiation of radioactive holmium to the various cancer sites. The homogeneity of the prepared sol-gel silica holmium monoliths was investigated by Back Scattered Electron Imaging of Scanning Electron Microscope equipped with Energy Dispersive X-ray Analysis, X-ray Induced Photoelectron Spectroscopy and Nuclear Magnetic Resonance Spectroscopy. The biodegradation of the monoliths was investigated in Simulated Body Fluid and TRIS (Trizma pre-set Crystals) solution. The results show that by suitable tailoring of the sol-gel processing parameters holmium can be homogeneously incorporated in the silica matrix with a controlled biodegradation rate.

Current role of selective internal irradiation with yttrium-90 microspheres in the management of hepatocellular carcinoma: a systematic review

PURPOSE

This article reviews the role of selective internal irradiation (SIR) with yttrium-90 ((90)Y) microspheres for hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

Studies were identified by searching Medline and PubMed databases for articles from 1990 to 2009 using the keywords "selective internal irradiation," "hepatocellular carcinoma," "therapeutic embolization," and "yttrium-90."

RESULTS

(90)Y microspheres are a safe and well-tolerated therapy for unresectable HCC (median survival range, 7 -21.6 months). The evidence was limited to cohort studies and comparative studies with historical control. (90)Y microspheres have been reported to downstage unresectable HCC to allow for salvage treatments with curative intent, act as a bridging therapy before liver transplantation, and treat HCC with curative intent for patients who are not surgical candidates because of comorbidities.

CONCLUSIONS

(90)Y microsphere is recommended as an option of palliative therapy for large or multifocal HCC without major portal vein invasion or extrahepatic spread. It can also be used for recurrent unresectable HCC, as a bridging therapy before liver transplantation, as a tumor downstaging treatment, and as a curative treatment for patients with associated comorbidities who are not candidates for surgery.

Approach to radiation therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the 5th most common cancer and the third most common cause of cancer-related death in the world with an estimated incidence of approximately 1 million new cases annually, has becoming a major global health problem in the world. A variety of treatment modalities, including resection, liver transplantation, transarterial chemoembolization (TACE), local ablative therapy and radiation therapy (RT) have been reported. Although partial hepatectomy and liver transplantation may offer the best chance of cure, only 15% of the patients have the chance to be treated by surgery when diagnosed. The effectiveness of systemic chemotherapy for HCC has been minimal, and local ablative therapy may offer comparable survival in patients with small HCC and preserve liver function. Recently, with developments in radiotherapy techniques, radiotherapy has been shown to play potential roles in a wide spectrum of HCC and to become more important so that it is necessary to evaluate the effect of radiotherapy in treatment of HCC. This paper is aiming mainly at the current radiation therapy strategies and their current advances, the optimal radiation therapy strategies will complement the current treatments and improve the treatment efficiency.

Holmium-166 poly(L-lactic acid) microsphere radioembolisation of the liver: technical aspects studied in a large animal model

Objective

To assess the accuracy of a scout dose of holmium-166 poly(L-lactic acid) microspheres (¹⁶⁶Ho-PLLA-MS) in predicting the distribution of a treatment dose of ¹⁶⁶Ho-PLLA-MS, using single photon emission tomography (SPECT).

Methods

A scout dose (60 mg) was injected into the hepatic artery of five pigs and SPECT acquired. Subsequently, a ‘treatment dose’ was administered (540 mg) and SPECT, computed tomography (CT) and magnetic resonance imaging (MRI) of the total dose performed. The two SPECT images of each animal were compared. To validate quantitative SPECT an ex vivo liver was instilled with ¹⁶⁶Ho-PLLA-MS and SPECT acquired. The liver was cut into slices and planar images were acquired, which were registered to the SPECT image.

Results

Qualitatively, the scout dose and total dose images were similar, except in one animal because of catheter displacement. Quantitative analysis, feasible in two animals, tended to confirm this similarity (r² = 0.34); in the other animal the relation was significantly better (r² = 0.66). The relation between the SPECT and planar images acquired from the ex vivo liver was strong (r² = 0.90).

Conclusion

In the porcine model a scout dose of ¹⁶⁶Ho-PLLA-MS can accurately predict the biodistribution of a treatment dose. Quantitative ¹⁶⁶Ho SPECT was validated for clinical application.

Clinical features and treatment outcomes of advanced stage primary hepatic angiosarcoma

BACKGROUND

Primary hepatic angiosarcoma is a very rare malignancy with a poor prognosis. While surgical resection has been validated as curative choice, most cases are diagnosed too late for resection. Nonetheless, treatment protocols have not been established and also there are very few reports on the clinical features and treatment outcomes.

PATIENTS AND METHODS

Among 11,939 patients diagnosed with primary hepatic tumors from January 1985 to December 2007 at two centers, five patients were diagnosed with primary hepatic angiosarcoma. We analyzed patients' demographics, tumor characteristics, treatment modality, and outcomes using imaging, serology, and pathology.

RESULTS

All five patients were diagnosed at advanced stage with distant metastases. The most common symptom was abdominal pain. The levels of the tumor markers were within the normal range and serological tests were negative for hepatitis B and C viruses. Two of four patients who received chemotherapy died <3 months after diagnosis, but the other two patients survived >6 months.

CONCLUSIONS

A combination of chemotherapy resulted in an improved outcome for two of four patients, suggesting the potential usefulness of palliative chemotherapy to improve survival. This case study may aid in planning chemotherapy for patients with advanced hepatic angiosarcoma.

Biliary complications associated with selective internal radiation (SIR) therapy for unresectable liver malignancies

Selective internal radiation (SIR) therapy using 90yttrium microspheres is effective for treating selected cases of unresectable liver malignancies with little morbidity. We herein report two cases illustrating a very rare complication of SIR. A 68-year-old patient with inoperable recurrent hepatocellular carcinoma received one treatment of SIR with 90yttrium microspheres and 4 months later presented with obstructive jaundice. Percutaneous transhepatic cholangiography revealed diffusely dilated intrahepatic ducts with multiple biliary strictures. Hepatic angiography showed normal hepatic arterial branches with no evidence of vascular insufficiency. Liver biopsy finally revealed cholestasis, cholangitis, and fibrosis, consistent with radiation-induced damage. Another 56-year-old patient with unresectable colorectal liver metastases presented with cholangitis 4 weeks after SIR. Ultrasonography showed no biliary dilatation, and endoscopic retrograde cholangiopancreatography demonstrated a normal biliary tree. Liver biopsy subsequently confirmed radiation-induced cholangitis.

Radionuclides delivery systems for nuclear imaging and radiotherapy of cancer

The recent developments of nuclear medicine in oncology have involved numerous investigations of novel specific tumor-targeting radiopharmaceuticals as a major area of interest for both cancer imaging and therapy. The current progress in pharmaceutical nanotechnology field has been exploited in the design of tumor-targeting nanoscale and microscale carriers being able to deliver radionuclides in a selective manner to improve the outcome of cancer diagnosis and treatment. These carriers include chiefly, among others, liposomes, microparticles, nanoparticles, micelles, dendrimers and hydrogels. Furthermore, combining the more recent nuclear imaging multimodalities which provide high sensitivity and anatomical resolution such as PET/CT (positron emission tomography/computed tomography) and SPECT/CT (combined single photon emission computed tomography/computed tomography system) with the use of these specific tumor-targeting carriers constitutes a promising rally which will, hopefully in the near future, allow for earlier tumor detection, better treatment planning and more powerful therapy. In this review, we highlight the use, limitations, advantages and possible improvements of different nano- and microcarriers as potential vehicles for radionuclides delivery in cancer nuclear imaging and radiotherapy.

Inoperable colorectal liver metastases: a declining entity?

BACKGROUND

Untreated colorectal liver metastases (CLMs) have a dismal prognosis. Surgery remains the gold standard of treatment, but many patients will have inoperable disease at presentation. Until recently, the outlook for such patients was bleak. The purpose of this review was to report on available options in the treatment CLMs, which would be considered unresectable by conventional evaluation.

METHODS

Inclusion criteria were articles published in English-language journals reporting on either retrospective or prospective cohorts of patients undergoing treatment for conventionally inoperable CLM. Main outcome measures were survival, resectability rates, morbidity and mortality following treatment of the patients' disease.

RESULTS

Improved chemotherapy regimes and other innovative treatments have opened up new options for such patients and may even render conventionally inoperable disease resectable. The aim of treatment should be down-staging of metastases to achieve resectability, however, other treatments such as ablation may be also be used (either alone or in conjunction with resection).

CONCLUSION

A nihilistic attitude to the patient with seemingly inoperable liver metastases should be discouraged. Discussion of such patients at multi-disciplinary meetings is essential in order to plan and monitor treatments.

Radioembolization for unresectable neuroendocrine hepatic metastases using resin 90Y-microspheres: early results in 148 patients

PURPOSE

The use of 90Y-microspheres to treat unresectable liver metastases originating from a variety of neuroendocrine tumors was reviewed.

MATERIALS AND METHODS

This is a retrospective review from 10 institutions of patients given 90Y-microsphere therapy for neuroendocrine hepatic metastases. Physical, radiographic, biochemical, and clinical factors associated with treatment and response were examined. All patients were followed with laboratory and imaging studies at regular intervals until death, or censured whether other therapy was given after brachytherapy. Toxicities (acute and late) were recorded, and survival of the group determined.

RESULTS

A total of 148 patients were treated with 185 separate procedures. The median age was 58 years (26-95 years) at treatment with median performance status of Eastern Cooperative Oncology Group (0). The median activity delivered was 1.14 GBq (0.33-3.30 GBq) with a median of 99% of the planned activity able to be given (38.1%-147.4%). There were no acute or delayed toxicity of Common Terminology Criteria for Adverse Events v3.0 grade 3 in 67% of patients, with fatigue (6.5%) the most common side effect. Imaging response was stable in 22.7%, partial response in 60.5%, complete in 2.7% and progressive disease in 4.9%. No radiation liver failure occurred. The median survival is 70 months.

CONCLUSION

Radioembolization with 90Y-microspheres to the whole liver, or lobe with single or multiple fractions are safe and produce high response rates, even with extensive tumor replacement of normal liver and/or heavy pretreatment. The acute and delayed toxicity was very low without a treatment related grade 4 acute event or radiation induced liver disease in this modest-sized cohort. The significant objective response suggests that further investigation of this approach is warranted.

Adjuvant intra-arterial iodine-131-labeled lipiodol for resectable hepatocellular carcinoma: a prospective randomized trial-update on 5-year and 10-year survival

OBJECTIVE

In this prospective randomized trial, we attempted to find out if 1 dose of postoperative adjuvant intra-arterial iodine-131-labeled lipiodol could reduce the rate of local recurrence, and increase disease-free and overall survival for patients with hepatocellular carcinoma (HCC). This study evaluated the long-term outcome.

BACKGROUND

Resection of HCC is potentially curative, but local recurrence is common. However, there is currently no effective adjuvant therapy. Early results after closing the trial (Lau et al. Lancet 1999;353:797-801) showed that 1 dose of intra-arterial I-lipiodol given after curative resection significantly decreased the rate of recurrence, and increased disease-free and overall survival.

METHODS

Patients who underwent curative resection for HCC and recovered within 6 weeks were randomly assigned one 1850 MBq dose of I-lipiodol or no further treatment (controls). We compared rates of recurrence, and long-term disease-free and overall survival (the primary endpoints) between the 2 groups by intention-to-treat.

RESULTS

Between April 1992 and August 1997, we recruited 43 patients: 21 were randomized to receive intra-arterial I-lipiodol and 22 to receive no adjuvant treatment. I-lipiodol had no significant toxic effects. During a median follow-up of 66 (range, 3-198) months, there were 10 (47.6%) recurrences among the 21 patients in the adjuvant treatment group, compared with 14 (63.6%) in the control group (P = 0.29). The actuarial 5-year disease-free survival in the treatment and control groups was 61.9% and 31.8%, respectively (P = 0.0397). The actuarial 5-year overall survival in the treatment and control groups was 66.7% and 36.4%, respectively (P = 0.0433). The actuarial 7-year disease-free survival in the treatment and control groups was 52.4% and 31.8%, respectively (P = 0.0224). The actuarial 7-year overall survival in the treatment and control groups was 66.7% and 31.8%, respectively (P = 0.0243). The actuarial 10-year disease-free survival in the treatment and control groups was 47.6% and 27.3%, respectively (P = 0.0892). The actuarial 10-year overall survival in the treatment and control groups was 52.4% and 27.3%, respectively (P = 0.0905).

CONCLUSIONS

In patients with HCC, adjuvant intra-arterial I-lipiodol after curative liver resection provided survival benefit on the disease-free survival and overall survival, although the difference became statistically insignificant at 8 years after randomization.

Targeted therapy in nuclear medicine—current status and future prospects

In recent years, a number of new developments in targeted therapies using radiolabeled compounds have emerged. New developments and insights in radioiodine treatment of thyroid cancer, treatment of lymphoma and solid tumors with radiolabeled monoclonal antibodies (mAbs), the developments in the application of radiolabeled small receptor-specific molecules such as meta-iodobenzylguanidine and peptides and the position of locoregional treatment in malignant involvement of the liver are reviewed. The introduction of recombinant human thyroid-stimulating hormone and the possibility to enhance iodine uptake with retinoids has changed the radioiodine treatment protocol of patients with thyroid cancer. Introduction of radiolabeled mAbs has provided additional treatment options in patients with malignant lymphoma, while a similar approach proves to be cumbersome in patients with solid tumors. With radiolabeled small molecules that target specific receptors on tumor cells, high radiation doses can be directed to tumors in patients with disseminated disease. Radiolabeled somatostatin derivatives for the treatment of neuroendocrine tumors are the role model for this approach. Locoregional treatment with radiopharmaceuticals of patients with hepatocellular carcinoma or metastases to the liver may be used in inoperable cases, but may also be of benefit in a neo-adjuvant or adjuvant setting. Significant developments in the application of targeted radionuclide therapy have taken place. New treatment modalities have been introduced in the clinic. The concept of combining therapeutic radiopharmaceuticals with other treatment modalities is more extensively explored.

Liver Embolizations in Oncology. A Review. Part II. Arterial Radioembolizations, Portal Venous Embolizations, Experimental Arterial Embolization Procedures

Arterial embolization of the liver may temporarily retard the growth of its primary and secondary tumors which are both mainly nourished arterially. Addition of radioisotopes, mostly (131)I or (90)Y, results in radioembolizations which predominantly act by radiation and less by ischemia. They may therefore be utilized in the absence of portal venous flow when conventional embolization is hazardous. (131)I-oily radioembolization seems to prolong short-term survival in such patients with unresectable hepatocellular cancers, and to improve the prognosis after resection of hepatocellular cancer. The procedure does however not palliate better than "cold" chemoembolization in patients with preserved portal flow, except for having milder side effects. Embolization with (90)Y-coupled microspheres may shrink primary and secondary liver tumors but has so far unproven effects on survival. Embolization of portal venous branches gives compensatory hypertrophy of the non-embolized liver and can increase the volume of the future remnant liver before resection. This diminishes the risk for postoperative liver failure after extensive resection and/or in the presence of chronic liver disease, and permits wider surgical indications. Tumor growth may however be accelerated, and the hypertrophy is inhibited by severe liver parenchymal disease in which situation the method would be most needed. Experimental use of liver arterial embolizations includes combined arterial and portal embolizations, i.e. "chemical hepatectomy," arterial embolizations before external radiotherapy, administration of boron for neutron capture therapy, immunoembolizations, and future gene therapy.

Inoperable hepatocellular carcinoma: transarterial 188Re HDD-labeled iodized oil for treatment--prospective multicenter clinical trial

PURPOSE

To prospectively evaluate, in a multicenter clinical trial, dosimetry-guided transarterial radionuclide therapy (TART) with rhenium 188 ((188)Re) 4-hexadecyl 1,2,9,9-tetramethyl-4,7-diaza-1,10-decanethiol (HDD)-labeled iodized oil in inoperable hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Ninety-three patients were recruited from 2000 to 2005 for this ethics committee-approved study. Informed written consent was obtained. After complete clinical evaluation (including assessment of liver status, serum alpha-fetoprotein [AFP] level, tumor size, portal vein status, Child-Pugh classification, Okuda staging), radiation absorbed dose (RAD) to various organs, including tumor, was calculated after injecting 185 MBq of (188)Re HDD iodized oil via the hepatic artery. From this value, the maximum tolerable activity of (188)Re, defined as the amount of radioactivity delivering no more than 12 Gy of RAD to lungs, 30 Gy to normal liver, or 1.5 Gy to bone marrow, was calculated and injected.

RESULTS

Mean patient age was 53 years (80 men and 13 women). Sixty-eight percent of patients had serologic evidence of hepatitis B and/or C; 40% had clinicoradiologic evidence of cirrhosis. Mean tumor diameter was 10.3 cm +/- 4.4, with 40% of patients having more than three lesions; in 50% of patients, tumor was either unilateral, occupying 50% or more of the liver, or bilateral. AFP was elevated in 68% of patients and was elevated to more than 300 ng/mL in 44% of patients. There was portal vein thrombosis in 38% of patients, Child-Pugh status B disease in 37% of patients, and Okuda stage II or III disease in 50% of patients. Mean first administered activity was 5.3 GBq +/- 1.6, which delivered 88 Gy of RAD to the tumor. Treatment was tolerated well. Of 66 patients in whom complete tumor response occurred, five (8%) had complete tumor mass ablation, 17 (26%) had a partial response (>50% tumor reduction), and 23 (35%) had stable disease. Only RAD to the tumors was found to be significantly (P = .001) associated with tumor and/or AFP response. Survival rates at 6, 9, 12, 24, and 36 months among patients with objective tumor response were 100%, 95%, 90%, 58%, and 30%, respectively, with a median survival of 980 days.

CONCLUSION

TART appears to be a safe, effective, and promising therapeutic option in patients with inoperable HCC.

Assessment of supra-additive effects of cytotoxic drugs and low dose rate irradiation in an in vitro model for hepatocellular carcinoma

The use of 5-fluorouracil, topotecan, or gemcitabine was tested for enhancement of the effects of low dose rate (LDR) irradiation in an in vitro model for hepatocellular carcinoma. For comparison, all drugs were tested in combination with high dose rate (HDR) gamma-irradiation as well. Multicellular spheroids of HepG2 cells were exposed to HDR or LDR irradiation by means of external beam cobalt-60 or rhenium-188 (188Re), respectively, dissolved in the culture medium. Secondly, exposure to irradiation was combined with the cytotoxic drug. Toxicity was evaluated by means of a quantitative spheroid outgrowth assay and histology. For 5-fluorouracil, supra-additive effects were observed in combination with HDR irradiation. With 188Re, the supra-additive toxicity was only transient. For topotecan and 188Re, no supra-additive effects were seen, whereas the addition of HDR irradiation at the end of the topotecan exposure yielded lasting supra-additive effects. Incubation with gemcitabine followed by exposure to HDR irradiation, induced a synergistic toxicity on the outgrowth. No supra-additive effects were observed when HDR irradiation was added at the start of the incubation with gemcitabine or combined with LDR irradiation. For all drugs tested, supra-additive effects were observed with HDR irradiation if the timing of the irradiation was appropriate. For 188Re, no lasting supra-additive effects were observed.

Technology insight: Image-guided therapies for hepatocellular carcinoma--intra-arterial and ablative techniques

Locoregional techniques have become the mainstay of therapy for patients with unresectable hepatocellular carcinoma (HCC). Such image-guided interventions include catheter-based approaches (transarterial chemoembolization and yttrium-90 radiotherapy) and locoregional ablative techniques, either chemical (percutaneous ethanol injection), or thermal (radiofrequency ablation, laser ablation, microwave ablation and cryoablation). These therapies are mainly utilized for palliation, but have also been used with curative intent. In selected cases, percutaneous interventional treatments have shown good results (5-year survival 40-50%), but, even when chosen as first-line treatment, have not been able to achieve the response rates and outcomes achieved by surgical options (resection or transplantation). New promising image-guided therapies are continuously emerging, as we attempt to improve tumor targeting, minimize hepatic toxicity and ultimately improve quality of life and survival of patients with HCC. With new technologies in imaging and drug delivery becoming available, it is likely that, in the future, patients with HCC will be best treated by a multidisciplinary team approach, utilizing a combination of techniques to improve patient survival. This review outlines the current status of the most commonly used image-guided locoregional interventions in the treatment of patients with HCC, and describes recent research and advances related to image-guided interventions for liver cancer.

Management of postsurgical recurrence of hepatocellular carcinoma with rhenium 188-HDD labeled iodized oil

Surgical resection with partial hepatectomy is the treatment of choice in patients with hepatocellular carcinoma (HCC). However, after recurrence, which is common, such patients have limited therapeutic options. In the present report, transarterial radionuclide therapy (TART) with rhenium 188 HDD-labeled Lipiodol was used to treat a patient with postsurgical recurrence of HCC. The patient tolerated therapy well and the lesions were completely ablated with a single dose of 188Re; the patient is free of disease for 14 months. TART with 188Re-HDD Lipiodol appears to be a promising new therapy in case of HCC recurrence after partial hepatectomy and requires further investigation.

Resin 90Y-microsphere brachytherapy for unresectable colorectal liver metastases: modern USA experience

PURPOSE

Salvage therapy for patients with unresectable colorectal liver metastases that were refractory to oxaliplatin and irinotecan was performed via radioactive microspheres. High doses of radiation were delivered to tumors from permanently implanted 90Y microspheres, delivered through the hepatic arterial vessels.

METHODS AND MATERIALS

Patients from 7 institutions were selected for treatment after screening-defined vascular access to all the tumors, and imaging-confirmed microspheres would be implanted only in the liver tumors. All patients were followed with laboratory and imaging studies at regular intervals until death. Toxicities, both acute and late, were recorded, and actuarial survival determined.

RESULTS

A total of 208 patients were treated from April 2002 to April 2005. Median follow-up of the 129 men and 79 women is 13 months (range, 1-42 months). Median survival is 10.5 months for responders but only 4.5 months in nonresponders. No treatment-related procedure deaths or radiation-related venoocclusive liver failures were found. Computed tomography partial response was 35%; positron emission tomography response of 91% and reduction in carcinoembryonic antigen of 70% were achieved.

CONCLUSIONS

In this group of heavily pretreated patients, radioactive microspheres produced an encouraging median survival, with acceptable toxicity, and a significant objective response rate, which suggests that further investigation of this approach is warranted.

Clinical applications of 188Re-labelled radiopharmaceuticals for radionuclide therapy

188Re is a radionuclide in which there is widespread interest for therapeutic purposes because of its favourable physical characteristics. Moreover, it can be eluted from an on-site installable 188W/188Re generator, which has a useful shelf-life of several months. Most of the clinical experiences gained with 188Re concern the use of 188Re-1,1-hydroxyethylidenediphosphonate (188Re-HEDP) for bone pain palliation in patients suffering prostate cancer. The maximum tolerated activity was 3.3 GBq 188Re-HEDP and if the platelet count exceeded 200 x 10(9) l(-1), the administration of 4.4 GBq appeared safe. Evidence for repeated administrations of 188Re-HEDP rather than single injections was established. In general, pain palliation occurs in 60-92% of patients with only moderate transient toxicity, mainly related to changes in blood counts. Also in haematology, radioimmunotherapy by means of 188Re might play a role by selectively targeting the bone marrow in patients undergoing conditioning prior to haematopoetic stem cell transplantation. The feasibility of such an approach was proven using a Re-labelled monoclonal antibody directed toward the CD66-antigen. More recently, encouraging safety data on locoregional treatment of primary liver tumours using 188Re-labelled lipiodol were reported. The normal organs at greatest risk for toxicity are the normal liver and the lungs. About 50% of the patients reported mild and transient side effects, mainly consisting of low grade fever, right hypochondrial discomfort or aggravation of pre-existing liver impairment. Besides the applications in oncology 188Re-based therapies have also been pioneered for benign condition such as prevention of re-stenosis following angioplasty and for radiosynovectomy in cases of refractory arthritis.

Clinical applications of newer radionuclide therapies

When radio-iodine was first used in the treatment of metastasized thyroid carcinoma in 1943, its success in terms of tumour response, quality of life improvement and survival was considered a 'miracle', as in those days metastatic cancer was generally fatal. Inspired by this, many efforts have been made to apply radioisotope therapy to other tumours. Radionuclide therapy uses radioactive isotopes labelled with specific targeting agents that aim to deliver the irradiation of the isotope to the tumour, while sparing normal tissues. Its unique modality allows to systemically target radiosensitive tumours throughout the body. Another important principle is its so-called 'cross-fire' action, whereby, owing to the larger reach of the radiation in relation to the cell diameter, a tumour cell receives lethal hits also from isotopes in the neighbourhood that are not directly associated with this cell. The treatment is therefore less hampered by inhomogeneous distribution and metabolism than for example chemo- or immunotherapy. The European Association of Nuclear Medicine has issued guidelines on so-called 'established' therapies (www.eanm.org), i.e. hyperthyroidism, thyroid carcinoma, refractory synovitis, bone metastases, mIBG therapy, 32P therapy and Lipiodol therapy. Newer therapies include radio-peptide therapy, radio-immunotherapy of lymphoma and microsphere therapy for liver cancer. The aim of a recently held workshop at the ECCO13 conference 2005 and this review is to inform the oncology community about these new developing therapies.

The effect of benzamide riboside on the VX2 model of liver cancer in rabbits

PURPOSE

Benzamide riboside (BR) causes apoptosis in multiple tumor cell lines by its inhibition of guanylate biosynthesis. The purpose of this study was to determine the feasibility of the use of BR as a therapeutic agent for hepatic artery infusional cancer therapy in a rabbit VX2 papilloma tumor model.

MATERIALS AND METHODS

VX2 tumor was implanted into the left lobe of the liver of each of 14 New Zealand White rabbits and allowed to grow for 19 days +/- 3. The proper hepatic artery was selected with a 3-F catheter via right femoral cutdown. The animals were treated with one infusion of 0.9% saline solution (n = 2), 1 mg/kg BR (n = 4), 5 mg/kg BR (n = 4), or 10 mg/kg BR (n = 4). One animal treated with 5 mg/kg BR did not develop tumor. Livers were explanted after 24 hours and sectioned through the tumor. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining was performed on the slides and they were imaged at a magnification of 40 to detect apoptotic cells. Four random fields were obtained from each slide and the percentage of apoptotic cells was calculated by dividing the number of TUNEL-positive cells by the total number of cells. Sections of liver not involved with tumor were seen in five animals: two that received 1 mg/kg BR, one that received 5 mg/kg, and two that received 10 mg/kg.

RESULTS

The mean tumor apoptosis rates were 1.3% with saline solution treatment, 44.8% with 1 mg/kg BR, 52.7% with 5 mg/kg BR, and 70.7% with 10 mg/kg BR. The mean tumor apoptosis in treated animals was significantly greater than in control animals (P = .003) and mean tumor apoptosis was significantly greater with 10 mg/kg BR than with 1 mg/kg BR (P = .03). There were no apoptotic cells in normal liver treated with 1 mg/kg BR or 10 mg/kg BR. The animal that received 5 mg/kg BR exhibited 10.5% apoptotic cells in the field examined (eight of 76 cells). In the animal treated with 5 mg/kg BR but in which tumor did not grow, only one of 76 cells (0.65%) was apoptotic in the area of the injection scar.

CONCLUSION

BR induces apoptosis in VX2 tumor in the rabbit model with minimal apoptosis in normal liver.

Eradication of hepatocellular carcinoma xenografts by radiolabelled, lipiodol-inducible gene therapy

The promoter region of the early-growth response-1(Egr-1) gene has been shown to be activated by external radiation, thus making a selective tumoricidal effect possible. A previous experiment showed that the Egr-1 promoter can be activated by internal radiation using radioisotopes as well as external radiation. Internal radiation using I-131 lipiodol (I-131-Lip) has been established as one of the most useful therapeutic strategies against hepatoma. We herein linked the Egr-1 promoter to the herpes simplex virus-thymidine kinase (HSV-TK) gene, and investigated its efficacy in hepatoma gene therapy in combination with I-131-Lip. A luciferase assay showed the Egr-1-promoter activity to be markedly increased in hepatoma tissue specimens in an I-131-dose-dependent manner, whereas a less than two-fold increase in this activity was observed in other organs. In addition, the radioactivity derived from I-131 was selectively accumulated in the tumor tissue specimens. To examine the efficacy of EgrTK/ganciclovir (GCV) gene therapy in vivo, subcutaneous hepatoma xenografts in nude mice were transfected using a hemagglutinating virus of Japan (HVJ)-liposome vector. Complete tumor regression was observed in all the EgrTK-transfected tumors following combination treatment with I-131-Lip and GCV 42 days after treatment without any side effects (n=8). In contrast, the tumors continued to grow in all control mice (n=10). Furthermore, the serum alpha-fetoprotein levels decreased in the combination therapy group, while they increased in the controls. In conclusion, these data indicate that Egr-1 promoter-based gene therapy combined with internal radiation has a selective effect on hepatoma tumors while also showing an improved in vivo efficacy. This combination therapy might, therefore, be an effective human hepatoma gene therapy, even in advanced multiple cases.