Liver transplantation for hepatocellular carcinoma: a surgical perspective

Radiomodulating Properties of Superparamagnetic Iron Oxide Nanoparticle (SPION) Agent Ferumoxytol on Human Monocytes: Implications for MRI-Guided Liver Radiotherapy

Superparamagnetic iron oxide nanoparticles (SPION) have attracted great attention not only for therapeutic applications but also as an alternative magnetic resonance imaging (MRI) contrast agent that helps visualize liver tumors during MRI-guided stereotactic body radiotherapy (SBRT). SPION can provide functional imaging of liver parenchyma based upon its uptake by the hepatic resident macrophages or Kupffer cells with a relative enhancement of malignant tumors that lack Kupffer cells. However, the radiomodulating properties of SPION on liver macrophages are not known. Utilizing human monocytic THP-1 undifferentiated and differentiated cells, we characterized the effect of ferumoxytol (Feraheme®), a carbohydrate-coated ultrasmall SPION agent at clinically relevant concentration and therapeutically relevant doses of gamma radiation on cultured cells in vitro. We showed that ferumoxytol affected both monocytes and macrophages, increased the resistance of monocytes to radiation-induced cell death and inhibition of cell activity, and supported the anti-inflammatory phenotype of human macrophages under radiation. Its effect on human cells depended on the duration of SPION uptake and was radiation dose-dependent. The results of this pilot study support a strong mechanism-based optimization of SPION-enhanced MRI-guided liver SBRT for primary and metastatic liver tumors, especially in patients with liver cirrhosis awaiting a liver transplant.

Stereotactic Body Radiation Therapy (SBRT) for Hepatocellular Carcinoma (HCC) With Single Photon Emission Computed Tomography (SPECT) Functional Treatment Planning in Patients With Advanced Hepatic Cirrhosis

Purpose

We report on the feasibility and outcomes of liver stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC) with single-photon emission computed tomography (SPECT) functional treatment planning in patients with Child-Pugh (CP) B/C cirrhosis.

Methods and Materials

Liver SPECT with 99mTc-sulfur colloid was coregistered to treatment planning computed tomography (CT) for the guided avoidance of functional hepatic parenchyma during SBRT. Functional liver volumes (FLVs) obtained from SPECT were compared with anatomic liver volumes defined on the planning CT. Radiation dose constraints were adapted exclusively to FLV. Local control, toxicity, and survival were reported with at least 6 months of radiographic follow-up. Pre- and posttransplant outcomes were analyzed in a subset of patients who completed SBRT as a bridge to liver transplant. Model of End-Stage Liver Disease was used to score hepatic function before and after SBRT completion.

Results

With a median follow-up of 32 months, 45 patients (58 lesions) with HCC and CP-B/C cirrhosis received SBRT to a median dose of 45 Gy (3-5 fractions). FLV loss (34%, P < .001) was observed in all patients, and the functional and anatomic liver volumes matched well in a control group of noncirrhotic/non-HCC patients. Despite marked functional parenchyma retraction, the amount of FLV on SPECT exposed to the threshold irradiation was significantly less than the CT liver volumes (P < .001) because of the optimized beam placement during dosimetry planning. Twenty-three patients (51%) successfully completed orthotopic liver transplant, with a median time to transplant of 9.2 months. With 91% in-field local control, the overall 2-year survival was 65% (90% after the orthotopic liver transplant), with no incidence of radiation-induced liver disease observed within 3 to 4 months or accelerated CP class migration from B to C within the first 6 months post-SBRT. Mean Model of End-Stage Liver Disease-Na score was not significantly elevated at 3-month intervals after SBRT completion.

Conclusions

Functional treatment planning with 99mTc sulfur colloid SPECT/CT allows identification and avoidance of functional hepatic parenchyma in patients with CP-B/C cirrhosis, leading to low toxicity and satisfactory transplant outcomes.

Alpha-fetoprotein Level Predicts Recurrence After Transplantation in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of liver transplantation. In an attempt to predict their recurrence after liver transplantation, evaluation of tumor number and size, degree of histologic differentiation, and the presence of vascular invasion already have their importance established. In this context, the role of biologic markers such as alpha-fetoprotein (AFP) is still not clear. This retrospective cross-sectional study analyzed the AFP relationship with recurrence of HCC after orthotopic liver transplantation.The current study retrospectively analyzed data from 206 patients with a histopathologic confirmed HCC between 1997 and 2010.The overall survival rates at 1, 3, 5, and 14 years were 78.6%, 65.4%, 60.5%, and 38.7%, respectively. The frequency of recurrence was 15.5%, and recurrence was significantly associated with a lower survival rate (P < 0.001). No association was observed between survival and AFP level (P = 0.153). A correlation, however, was found between tumor recurrence and AFP level (P = 0.002). Univariate analysis of risk factors for recurrence revealed that an AFP level greater than 200 ng/mL, the number of tumors, the degree of cellular differentiation, and the presence of vascular invasion or satellite nodules were associated with relapse. By multivariate analysis, only an AFP level greater than 200 ng/mL remained as a risk factor.Although an elevated AFP level did not correlate with survival in HCC patients undergoing orthotopic liver transplantation, a high AFP level was associated with a 3.32-folds increase in the probability of HCC recurrence.

Identification and characterization of a novel small-molecule inhibitor of β-catenin signaling

Hepatocellular carcinoma (HCC), the third most common cause of cancer-related deaths worldwide, lacks effective medical therapy. Large subsets of HCC demonstrate Wnt/β-catenin activation, making this an attractive therapeutic target. We report strategy and characterization of a novel small-molecule inhibitor, ICG-001, known to affect Wnt signaling by disrupting β-catenin-CREB binding protein interactions. We queried the ZINC online database for structural similarity to ICG-001 and identified PMED-1 as the lead compound, with ≥70% similarity to ICG-001. PMED-1 significantly reduced β-catenin activity in hepatoblastoma and several HCC cells, as determined by TOPflash reporter assay, with an IC50 ranging from 4.87 to 32 μmol/L. Although no toxicity was observed in primary human hepatocytes, PMED-1 inhibited Wnt target expression in HCC cells, including those with CTNNB1 mutations, and impaired cell proliferation and viability. PMED-1 treatment decreased β-catenin-CREB binding protein interactions without affecting total β-catenin levels or activity of other common kinases. PMED-1 treatment of Tg(OTM:d2EGFP) zebrafish expressing GFP under the β-catenin/Tcf reporter led to a notable decrease in β-catenin activity. The PMED effect on β-catenin signaling lasted from 12 to 24 hours in vitro and 6 to 15 hours in vivo. Thus, using a rapid and cost-effective computational methodology, we have identified a novel and specific small-molecule inhibitor of Wnt signaling that may have implications for HCC treatment.

Alternol inhibits migration and invasion of human hepatocellular carcinoma cells by targeting epithelial-to-mesenchymal transition

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths worldwide. Such deaths are due, in large part, to its propensity to metastasize. We have examined the effect of alternol on human HCC cells and the underlying molecular mechanism. Therapeutic effects of alternol on cancer cell migration and invasion were analyzed with Boyden chamber and wound healing assays. Effects of alternol on the levels of various proteins involved in cancer cell migration and invasion were determined with gelatin zymography, immunofluorescence, and Western blotting. As shown, treatment with alternol has resulted in a concentration-dependent inhibition of cell migration and invasion of HepG2 cells. The inhibition of HCC invasion by alternol was associated with the suppression of MMP-9 expression and reversal of epithelial-to-mesenchymal transition (EMT). The above results indicated that alternol has the ability to inhibit the migration and invasion of human HCC cells by reversing the process of EMT, suggesting that alternol may be developed as an alternative drug for the treatment of HCC.

Liver Transplantation for Hepatocellular Carcinoma beyond Milan Criteria: Multidisciplinary Approach to Improve Outcome

The implementation of the Milan criteria (MC) in 1996 has dramatically improved prognosis after liver transplantation (LT) in patients with hepatocellular carcinoma (HCC). Liver transplantation has, thereby, become the standard therapy for patients with "early-stage" HCC on liver cirrhosis. The MC were consequently adopted by United Network of Organ Sharing (UNOS) and Eurotransplant for prioritization of patients with HCC. Recent advancements in the knowledge about tumor biology, radiographic imaging techniques, locoregional interventional treatments, and immunosuppressive medications have raised a critical discussion, if the MC might be too restrictive and unjustified keeping away many patients from potentially curative LT. Numerous transplant groups have, therefore, increasingly focussed on a stepwise expansion of selection criteria, mainly based on tumor macromorphology, such as size and number of HCC nodules. Against the background of a dramatic shortage of donor organs, however, simple expansion of tumor macromorphology may not be appropriate to create a safe extended criteria system. In contrast, rather the implementation of reliable prognostic parameters of tumor biology into selection process prior to LT is mandatory. Furthermore, a multidisciplinary approach of pre-, peri-, and posttransplant modulating of the tumor and/or the patient has to be established for improving prognosis in this special subset of patients.

The efficacy of radiofrequency ablation combined with transcatheter arterial chemoembolization for primary hepatocellular carcinoma in a cohort of 487 patients

Although diagnostic methods, surgical techniques, and perioperative care have undergone significant advancement over the past decades, the prognosis of primary hepatocellular carcinoma (HCC) remains discouraged because of the high postoperative recurrence rate and high cancer mortality. Radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) is a recently developed means for the treatment of HCC. In this study, we analyzed the efficacy of RFA plus TACE in 487 cases of HCC in our institution. We observed that the 1-, 2-, 3-, 4- and 5-year rates of overall survival rates after RFA and TACE treatment were 97.5% (475/487), 89.4% (277/310), 84.2% (181/215), 80.4% (150/186) and 78.7% (141/177), respectively. We did not find that age or tumor location (the caudate group or non-caudate group) plays a role in this cohort. However, we have identified that tumor recurrent status, the number of tumors, albumin (ALB), prothrombin time (PT) and platelet count (PLT) were significantly associated with poor overall survival in HCC patients receiving RFA combined with TACE. Interestingly, tumor size did not significantly impact overall survival, indicating that RFA combined with TACE for HCC treatment has the same efficiency for different sizes of tumors. Our results provide evidence for the rationale for using combined RFA and TACE in the treatment of primary HCC.