Radiation therapy for hepatocellular carcinoma

Synthesis of novel galactose functionalized gold nanoparticles and its radiosensitizing mechanism

BACKGROUND

Biocompatible gold nanoparticles (GNPs) are potentially practical and efficient agents in cancer radiotherapy applications. In this study, we demonstrated that GNPs can significantly modulate irradiation response of hepatocellular carcinoma cells in vitro and investigated the underlying mechanisms. We co-grafted galactose (GAL) targeting hepatocyte specific asialoglycoprotein receptor and Polyethylene Glycol (PEG) onto GNPs surfaces to increase GNPs targeting specificity and stability.

RESULTS

This novel GAL-PEG-GNPs and bare GNPs show similar appearance and cytotoxicity profiles, while more GAL-PEG-GNPs can be effectively uptaken and could enhance cancer cell killing.

CONCLUSION

GAL-PEG-GNPs have better radiosensitization to HepG2. The sensitization mechanism of GAL-PEG-GNPs is related to the apoptotic gene process activated by generation of a large amount of free radicals induced by GNPs.

Identification of Biologically Effective Dose-Volumetric Parameters That Predict Radiation-Induced Hepatic Toxicity in Patients Treated With Helical Tomotherapy for Unresectable Locally Advanced Hepatocellular Carcinoma

The purpose of this study is to identify dose-volumetric parameters that predict radiation-induced hepatic toxicity (RIHT) by analyzing the relationship between the biologically effective dose (BED) delivered to the normal liver and RIHT.The clinical and dosimetric data from 123 patients with unresectable hepatocellular carcinoma (HCC) treated with helical tomotherapy were analyzed. The median radiation dose was a 50 Gy in 4.5 Gy fractions (range, 30-60 Gy in 1.8-5.0 Gy fractions) to 95% of the planning target volume. RIHT was defined as a Child-Pugh score increase of at least 2 points within 3 months of helical tomotherapy completion.RIHT developed in 60 patients (48.7%). Multivariate logistic regression analysis showed that VBED20 (percentage of nontarget normal liver volume that received more than a BED of 20 Gy) was a significant parameter (P < 0.001), and the cut-off value was 40.8% with a sensitivity and specificity of 0.833 and 0.698, respectively, according to the receiver operating characteristic curve (P < 0.001).Maintaining a VBED20 below 40.8% will reduce the risk of RIHT, and the proposed normal liver tolerance curve could be a useful guideline when treating unresectable HCC patients with various radiotherapy dose schedules.

Dosimetric comparison of volumetric modulated arc therapy with robotic stereotactic radiation therapy in hepatocellular carcinoma

Purpose

To compare volumetric modulated arc therapy of RapidArc with robotic stereotactic body radiation therapy (SBRT) of CyberKnife in the planning and delivery of SBRT for hepatocellular carcinoma (HCC) treatment by analyzing dosimetric parameters.

Materials and Methods

Two radiation treatment plans were generated for 29 HCC patients, one using Eclipse for the RapidArc plan and the other using Multiplan for the CyberKnife plan. The prescription dose was 60 Gy in 3 fractions. The dosimetric parameters of planning target volume (PTV) coverage and normal tissue sparing in the RapidArc and the CyberKnife plans were analyzed.

Results

The conformity index was 1.05 ± 0.02 for the CyberKnife plan, and 1.13 ± 0.10 for the RapidArc plan. The homogeneity index was 1.23 ± 0.01 for the CyberKnife plan, and 1.10 ± 0.03 for the RapidArc plan. For the normal liver, there were significant differences between the two plans in the low-dose regions of V₁ and V₃. The normalized volumes of V₆₀ for the normal liver in the RapidArc plan were drastically increased when the mean dose of the PTVs in RapidArc plan is equivalent to the mean dose of the PTVs in the CyberKnife plan.

Conclusion

CyberKnife plans show greater dose conformity, especially in small-sized tumors, while RapidArc plans show good dosimetric distribution of low dose sparing in the normal liver and body.

Radiation induced liver disease: A clinical update

Radiation-induced liver disease (RILD) or radiation hepatitis is a sub-acute form of liver injury due to radiation. It is one of the most dreaded complications of radiation which prevents radiation dose escalation and re-irradiation for hepatobiliary or upper gastrointestinal malignancies. This complication should be kept in mind whenever a patient is planned for irradiation of these malignancies. Although, incidence of RILD is decreasing due to better knowledge of liver tolerance, improved investigation modalities and modern radiation delivery techniques, treatment options are still limited. In this review article, we have focussed on patho-physiology, risk factors, prevention and management of RILD.

Current and future treatments for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents a unique challenge for physicians and patients. There is no definitively curative treatment. Rather, many treatment and management modalities exist with differing advantages and disadvantages. Both current guidelines and individual patient concerns must be taken into account in order to properly manage HCC. In addition, quality of life issues are particularly complex in patients with HCC and these concerns must also be factored into treatment strategies. Thus, considering all the options and their various pros and cons can quickly become complex for both clinicians and patients. In this review, we systematically discuss the current treatment modalities available for HCC, detailing relevant clinical data, risks and rewards and overall outcomes for each approach. Surgical options discussed include resection, transplantation and ablation. We also discuss the radiation modalities: conformal radiotherapy, yttrium 90 microspheres and proton and heavy ion radiotherapy. The biologic agent Sorafenib is discussed as a promising new approach, and recent clinical trials are reviewed. We then detail currently described molecular pathways implicated in the initiation and progression of HCC, and we explore the potential of each pathway as an avenue for drug exploitation. We hope this comprehensive and forward-looking review enables both clinicians and patients to understand various options and thereby make more informed decisions regarding this disease.

Treatment of hepatocellular carcinoma: Steps forward but still a long way to go

Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the third cause of tumor associated deaths worldwide. HCC incidence rates are increasing in many parts of the world including developing and developed countries. Potentially curative treatments for HCC are resection and liver transplantation, but these are only suitable for patients with small tumors, meeting strict pre-defined criteria, or well-compensated liver disease. Early diagnosis of HCC can be achieved by surveillance of at-risk populations. For patients with non-resectable disease treatments modalities include loco-ablative and systemic therapies. In this review we focus on treatment options in HCC and their allocation. Although significant research is in progress, to this date, the results are unsatisfactory with limited long-term survival. In the fight against this deadly disease, there is still a long way to go.

HAb18G/CD147 promotes radioresistance in hepatocellular carcinoma cells: a potential role for integrin β1 signaling

Radiotherapy has played a limited role in the treatment of hepatocellular carcinoma (HCC) due to the risk of tumor radioresistance. A previous study in our laboratory confirmed that CD147 interacts with integrin β1 and plays an important role in modulating the malignant properties of HCC cells. In this study, we further evaluated the role of CD147 in the radioresistance of HCC and as a potential target for improving radiosensitivity. Upon irradiation, the colony formation, apoptosis, cell-cycle distribution, migration, and invasion of SMMC-7721, CD147-knockout SMMC-7721, HepG2, and CD147-knockdown HepG2 cells were determined. A nude mouse xenograft model and a metastatic model of HCC were used to detect the role of CD147 in radioresistance in vivo. Deletion of HAb18G/CD147 significantly enhanced the radiosensitivity of SMMC-7721 and HepG2 cells, and knocking out HAb18G/CD147 in SMMC-7721 cells attenuated irradiation-enhanced migration and invasion. The knockout and antibody blockade of CD147 decreased the tumor growth and metastatic potentials of HCC cells under irradiation. CD147-deleted SMMC-7721 cells showed diminished levels of calpain, cleaved talin, active integrin β1, and decreased p-FAK (Tyr397) and p-Akt (Ser473) levels. FAK and PI3K inhibitors, as well as integrin β1 antibodies, increased the radiation-induced apoptosis of SMMC-7721 cells. Our data provide evidence for CD147 as an important determinant of radioresistance via the regulation of integrin β1 signaling. Inhibition of the HAb18G/CD147 integrin interaction may improve the efficiency of radiosensitivity and provide a potential new approach for HCC therapy.

A prospective phase 2 multicenter study for the efficacy of radiation therapy following incomplete transarterial chemoembolization in unresectable hepatocellular carcinoma

PURPOSE

The purpose of this study was to investigate the efficacy and toxicity of radiation therapy (RT) following incomplete transarterial chemoembolization (TACE) in unresectable hepatocellular carcinoma (HCC).

METHODS AND MATERIALS

The study was designed as a prospective phase 2 multicenter trial. Patients with unresectable HCC, who had viable tumor after TACE of no more than 3 courses, were eligible. Three-dimensional conformal RT (3D-CRT) was added for HCC treatment with incomplete uptake of iodized oil, and the interval from TACE to RT was 4 to 6 weeks. The primary endpoint of this study was the tumor response after RT following incomplete TACE in unresectable HCC. Secondary endpoints were patterns of failure, progression-free survival (PFS), time to tumor progression (TTP), overall survival (OS) rates at 2 years, and treatment-associated toxicity. Survival was calculated from the start of RT.

RESULTS

Between August 2008 and December 2010, 31 patients were enrolled. RT was delivered at a median dose of 54 Gy (range, 46-59.4 Gy) at 1.8 to 2 Gy per fraction. A best objective in-field response rate was achieved in 83.9% of patients, with complete response (CR) in 22.6% of patients and partial response in 61.3% of patients within 12 weeks post-RT. A best objective overall response rate was achieved in 64.5% of patients with CR in 19.4% of patients and PR in 45.1% of patients. The 2-year in-field PFS, PFS, TTP, and OS rates were 45.2%, 29.0%, 36.6%, and 61.3%, respectively. The Barcelona Clinic liver cancer stage was a significant independent prognostic factor for PFS (P=.023). Classic radiation-induced liver disease was not observed. There were no treatment-related deaths or hepatic failure.

CONCLUSIONS

Early 3D-CRT following incomplete TACE is a safe and practical treatment option for patients with unresectable HCC.

Unresectable solitary hepatocellular carcinoma not amenable to radiofrequency ablation: multicenter radiology-pathology correlation and survival of radiation segmentectomy

Resection and radiofrequency ablation (RFA) are treatment options for hepatocellular carcinoma (HCC) <3 cm; there is interest in expanding the role of ablation to 3-5 cm. RFA is considered high-risk when the lesion is in close proximity to critical structures. Combining microcatheter technology and the localized emission properties of Y90, highly selective radioembolization is a possible alternative to RFA in such cases. We assessed the efficacy (response, radiology-pathology correlation, survival) of radiation segmentectomy in solitary HCC not amenable to RFA or resection. Patients with treatment-naïve, unresectable, solitary HCC ≤ 5 cm not amenable to RFA were included in this multicenter study. Administered dose, response rate, time-to-progression (modified Response Evaluation Criteria in Solid Tumors [mRECIST]), radiology-pathology correlation and long-term survival were assessed. In all, 102 patients were included in this study. mRECIST complete response (CR), partial response (PR), and stable disease (SD) were 47/99 (47%), 39/99 (39%), and 12/99 (12%), respectively. Median time-to-disease-progression was 33.1 months. In all, 33/102 (32%) patients were transplanted with a median (interquartile range [IQR]) time-to-transplantation of 6.3 months (3.6-9.7). Pathology revealed 100% and 50-99% necrosis in 17/33 (52%) and 16/33 (48%), respectively. Median overall survival was 53.4 months. Univariate analysis demonstrated a survival benefit for Eastern Cooperative Oncology Group (ECOG) 0 patients. In the multivariate model, age <65, ECOG 0, and Child-Pugh A were characteristics associated with longer survival.

CONCLUSION

Radiation segmentectomy is an effective technique with a favorable risk profile and radiology-pathology outcomes for solitary HCC ≤ 5 cm. This approach may allow for treatment of HCC in difficult locations. Since RFA and resection are not options given tumor location, there appears to be a strong rationale for this technique as second choice.

Sorafenib increases efficacy of vorinostat against human hepatocellular carcinoma through transduction inhibition of vorinostat-induced ERK/NF-κB signaling

Sorafenib is effective for patients with advanced hepatocellular carcinoma (HCC) and particularly for those who are unsuitable to receive life-prolonging transarterial chemo-embolization. The survival benefit of sorafenib, however, is unsatisfactory. Vorinostat also known as suberoylanilide hydroxamic acid (SAHA) is a histone deacetylase (HDAC) inhibitor with anti-HCC efficacy in preclinical studies. SAHA induces nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activity in vitro, which may lead to cancer cell progression and jeopardize cytotoxic effect of SAHA in HCC. The goal of this study was to investigate whether sorafenib enhances SAHA cytotoxicity against HCC through inhibition of SAHA-induced NF-κB activity. The human HCC cell line Huh7 transfected with dual reporter genes, luciferase (luc) and thymidine kinase (tk) with NF-κB response elements, was co-transfected with red fluorescent protein (rfp) gene for non-invasive molecular imaging to assess NF-κB activity and living cells simultaneously. Cell viability assay, DNA fragmentation, western blotting, electrophoretic mobility shift assay (EMSA) and multiple modalities of molecular imaging were used to assess the combination efficacy and mechanism of sorafenib and SAHA. The administration of high-dose SAHA (10 µM) with long treatment time (48 h) in vitro, and 25 mg/kg/day by gavage in HCC-bearing nude mice to induce NF-κB activity were performed. Sorafenib inhibited SAHA-induced NF-κB activity and the expression of NF-κB-regulated effector proteins while it increased the efficacy of SAHA against HCC both in vitro and in vivo. The mechanism of sorafenib to enhance SAHA efficacy on HCC is through the suppression of ERK/NF-κB pathway, which induces extrinsic and intrinsic apoptosis. Combination of sorafenib and SAHA may have the potential as new strategy against HCC.

Feasibility of stereotactic body radiation therapy with volumetric modulated arc therapy and high intensity photon beams for hepatocellular carcinoma patients

Background

To report technical features, early outcome and toxicity of stereotactic body radiation therapy (SBRT) treatments with volumetric modulated arc therapy (RapidArc) for patients with hepatocellular carcinoma (HCC).

Methods

Twenty patients (22 lesions) were prospectively enrolled in a feasibility study. Dose prescription was 50Gy in 10 fractions. Seven patients (35%) were classified as AJCC stage I-II while 13 (65%) were stages III-IV. Eighteen patients (90%) were Child-Pugh stage A, the remaining were stage B. All patients were treated with RapidArc technique with flattening filter free (FFF) photon beams of 10MV from a TrueBeam linear accelerator. Technical, dosimetric and early clinical assessment was performed to characterize treatment and its potential outcome.

Results

Median age was 68 years, median initial tumor volume was 124 cm³ (range: 6–848). Median follow-up time was 7.4 months (range: 3–13). All patients completed treatment without interruption. Mean actuarial overall survival was of 9.6 ± 0.9 months (95%C.L. 7.8-11.4), median survival was not reached; complete response was observed in 8/22 (36.4%) lesions; partial response in 7/22 (31.8%), stable disease in 6/22 (27.3%), 1/22 (4.4%) showed progression. Toxicity was mild with only 1 case of grade 3 RILD and all other types were not greater than grade 2. Concerning dosimetric data, Paddick conformity index was 0.98 ± 0.02; gradient index was 3.82 ± 0.93; V_95% to the clinical target volume was 93.6 ± 7.7%. Mean dose to kidneys resulted lower than 3.0Gy; mean dose to stomach 4.5 ± 3.0Gy; D_1cm³ to spinal cord was 8.2 ± 4.5Gy; D_1% to the esophagus was 10.2 ± 9.7Gy. Average beam on time resulted 0.7 ± 0.2 minutes (range: 0.4-1.4) with the delivery of an average of 4.4 partial arcs (range: 3–6) of those 86% non-coplanar.

Conclusions

Clinical results could suggest to introduce VMAT-RapidArc as an appropriate SBRT technique for patients with HCC in view of a prospective dose escalation trial.

Adjuvant radiotherapy in centrally located hepatocellular carcinomas after hepatectomy with narrow margin (<1 cm): a prospective randomized study

BACKGROUND

Although radiotherapy (RT) provides potential benefits for patients with hepatocellular carcinomas (HCCs) that are unsuitable for operation, the specific role of adjuvant RT in HCC after hepatectomy remains ill defined. The current study's aim was to evaluate the safety and efficacy of adjuvant RT for centrally located HCCs after narrow-margin (<1 cm) hepatectomy.

STUDY DESIGN

The study included 119 patients with centrally located HCCs who underwent narrow-margin hepatectomy between July 2007 and March 2012. Patients were prospectively randomized to receive adjuvant RT (n = 58) or were assigned to a control group (n = 61). Surgical outcomes, safety, and survival rates were evaluated.

RESULTS

Hepatectomy was successfully performed in all patients. No cases of radiation-induced liver disease were observed. One-, 3-, and 5-year recurrence-free survival rates were 78.1%, 56.5%, and 36.9% in the adjuvant RT group and 72.4%, 40.1%, and 16.0% in the control group, respectively (p = 0.06, log-rank test). Corresponding overall survival rates were 96.2%, 72.6%, 48.4%, and 89.6%, 74.5%, 37.2%, respectively (p = 0.48, log-rank test). One-, 3-, and 5-year recurrence-free survival rates in patients with small-diameter tumors (≤5 cm) were 88.8%, 67.4%, 42.9% in the adjuvant RT group and 82.3%, 42.9%, 21.5% in the control group (p = 0.03, log-rank test). Corresponding overall survival rates were 97.5%, 75.3%, 75.3%, and 94.7%, 84.1%, 65.4%, respectively (p = 0.92, log-rank test).

CONCLUSIONS

Adjuvant RT for centrally located HCCs after narrow-margin hepatectomy was technically feasible and relatively safe. No significant between-group difference was observed in recurrence-free and overall survival. The post-hoc subgroup comparison showed that adjuvant RT improved recurrence-free survival considerably, but not overall survival, in patients with small HCCs (≤5 cm). More in-depth studies are needed to validate this finding.

Three-dimensional conformal radiotherapy for hepatocellular carcinoma in patients unfit for resection, ablation, or chemotherapy: a retrospective study

PURPOSE

The purpose is to evaluate the feasibility, efficacy, and the toxicity of three-dimensional conformal radiotherapy (3DCRT) in patients with advanced hepatocelluar carcinoma (HCC) and inferior vena cava tumor thrombosis (IVCTT).

METHODS

Between 2007 and 2012, in a retrospective way, 9 patients (median age 69 years) with advanced HCC and IVCTT unfit for surgery, radiofrequency ablation, embolization, or chemotherapy were treated with three-dimensional conformal radiotherapy (3DCRT). The radiotherapy volume included both primary tumor and IVTT. The radiotherapy schedule was 50-52 Gy in 2 Gy fractions. Overall survival (OS), response to radiotherapy, visual analogue scale (VAS), and toxicity were assessed.

RESULTS

All patients demonstrated a response rate up to 60%. During radiotherapy, 3 patients experienced grade 1 nausea/vomit toxicity. All patients demonstrated an elevation of the liver enzymes (3 patients with grade 1 and 6 patients with grade 2). The mean VAS-score was decreased from 6.11 to 3.11, while the median overall survival was 24 months.

CONCLUSION

3DCRT achieves a very high local control rate and is suitable for patients with HCC and IVTT, while the documented radiation induced toxicity is moderate. It can be recommended for palliation in patients unable to undergo curative therapies.

Stereotactic Body radiation therapy for liver tumors with or without rotational intensity modulated radiation therapy

BACKGROUND

To evaluate the feasibility and efficacy of Stereotactic body radiation therapy (SBRT) for primary liver lesions and liver metastases treated with linear accelerators with or without rotational Intensity Modulated RadioTherapy (IMRT).

METHODS

Patients with either hepatocellular carcinoma, cholangiocarcinoma or metastatic liver lesions who had one to three lesions treated with SBRT in a single institution were retrospectively reviewed. Tumor response was evaluated according to EASL criteria 3 months after SBRT completion using MRI and/or abdominal CT scan. Responses were categorised as: Stable Disease (SD), Partial Response (PR), Complete Response (CR), Local Progression or Distant Progression in cases of new intra-hepatic lesions out-of-field or extra-hepatic metastases. Local Control (LC), Progression Free Survival (PFS), Overall Survival (OS) and treatment-related toxicities are reported.

RESULTS

Between 2007 and 2012, 20 patients with a total of 24 lesions were treated with SBRT. Fourteen patients presented hepatocellular carcinoma (HCC), the others had either metastatic lesions from colorectal cancer (CRC) or cholangiocarcinoma. The median diameter of the lesions was 23 mm (5-98).The dose per fraction ranged from 6 to 20 Gy with a median total dose of 60 Gy (range: 36-60 Gy). The dose was prescribed to the 80% isodose line covering the PTV.The median follow-up was 24 months (15.7-29.7).The actuarial LC rate was 78% for patients with HCC and 83% for those with adenocarcinoma and cholangiocarcinoma. Median OS was 37 months and OS rates were 83% at 12 and 24 months for HCC and 100% for adenocarcinoma. PFS was 54% for HCC and 50% for other types of tumors at 24 months.Acute grade 3-4 toxicities occurred in 2 patients; a small proportion of the other patients experienced grade 1 or 2 toxicities.

CONCLUSIONS

SBRT provides excellent local control with minimal side effects in selected patients.

Stereotactic body radiation therapy for hepatocellular carcinoma: prognostic factors of local control, overall survival, and toxicity

Purpose

Stereotactic body radiation therapy (SBRT) for hepatocellular carcinoma (HCC) has been evaluated in several recent studies. The CyberKnife^® is an SBRT system that allows for real-time tracking of the tumor. The purpose of this study was to evaluate the prognostic factors for local control and overall survival following this treatment.

Patients and Methods

75 patients with 96 liver-confined HCC were treated with SBRT at the Oscar Lambret Comprehensive Cancer Center. Fiducials were implanted in the liver before treatment and were used as markers to track the lesion’s movement. Treatment response was scored according to RECIST v1.1. Local control and overall survival were calculated using the Kaplan and Meier method. A stepwise multivariate analysis (Cox regression) of prognostic factors was performed for local control and overall survival.

Results

There were 67 patients with Child-Turcotte-Pugh (CTP) Class A and eight patients with CTP Class B. Treatment was administered in three sessions. A total dose of 40–45 Gy to the 80% isodose line was delivered. The median follow-up was 10 months (range, 3–49 months). The local control rate was 89.8% at 1 and 2 years. Overall survival was 78.5% and 50.4% at 1 and 2 years, respectively. Toxicity mainly consisted of grade 1 and grade 2 events. Higher alpha-fetoprotein (aFP) levels were associated with less favorable local control (HR=1.001; 95% CI [1.000, 1.002]; p=0.0063). A higher dose was associated with better local control (HR=0.866; 95% CI [0.753, 0.996]; p=0.0441). A Child-Pugh score higher than 5 was associated with worse overall survival (HR= 3.413; 95% CI [1.235, 9.435]; p=0.018).

Conclusion

SBRT affords good local tumor control and higher overall survival rates than other historical controls (best supportive care or sorafenib). High aFP levels were associated with lesser local control, but a higher treatment dose improved local control.

CT-pathologic correlation in primary hepatocellular carcinoma: an implication for target delineation

The purpose of this investigation was to analyze the correlation between CT size and gross pathologic size for subjects with primary hepatocellular carcinoma (HCC). This analysis included 174 patients with HCC who underwent surgery. Enhanced computed tomography (CT) was performed up to 30 days before surgery. After resection, the size of the tumor on gross pathologic examination was recorded. The maximal measurement in one dimension on axial imaging and pathologic examination was extracted for statistical analysis. The clinical and pathologic sizes were compared using a percent size difference (%Δsize) as an end point. A regression analysis was applied to study the association between pathologic and radiographic size. The median radiographic and pathologic size were 70.58 ± 38.9 mm and 68.59 ± 40.56 mm, respectively. The radiographic size was larger than or equal to the pathologic size in 110/174 tumors (63.2%), and smaller in 64/174 (36.8%) tumors. Overall, the radiographic and pathologic sizes were positively correlated (r = 0.983, P = 0.000). CT seemed to overestimate the tumor size by 2.16 mm compared to final pathology (P = 0.024). The median %Δsize was 3.3%. Pathologic tumor size was significantly underestimated in patients with a tumor size 3-5 cm (P = 0.011), Grade I HCC (P = 0.023), with clear boundary (P = 0.013). We concluded that CT size and pathologic size were positively correlated, but differences did exist. Utilizing the radiographic tumor when planning radiation would have covered 63.2% of gross tumors. For a radiographic tumor size < 50 mm, utilizing a 3-mm margin around the radiographic tumor would have covered 90% of gross lesions, while a margin of 5 mm would have covered 95%, and a margin of 15 mm would have covered 100%.

Rat model of fractionated (2 Gy/day) 60 Gy irradiation of the liver: long-term effects

The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small "scars" on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of "provisional clot"-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation.

Stereotactic radiosurgery for brain metastases from hepatocellular carcinoma

The purpose of this study is to investigate the possible role of stereotactic radiosurgery (SRS) in the management of patients with brain metastases from hepatocellular carcinoma (HCC). Thirty-two consecutive patients with 80 brain metastases from HCC were treated with SRS. Twenty-eight (87.5 %) patients were male, and the mean age of the patients was 54 ± 12 years (range 22-73). Twenty-seven (84.4 %) patients were classified as RTOG RPA Class 2. The mean tumor volume was 6.14 ± 11.3 cm(3) (range 0.01-67.3). The mean marginal dose prescribed was 20.1 ± 3.6 Gy (range 10.0-25.0). The median overall survival time after SRS was 11.3 ± 5.8 weeks (95 % CI 0-22.7). A greater total volume of brain metastases (>14 cm(3)) was the only independent prognostic factor (HR = 2.419; 95 % CI 1.040-5.624; p = 0.040). The actuarial control rate of brain metastases was 51.3 % at 4 months after SRS. The prescribed marginal dose (>18 Gy) was significantly related with the actuarial tumor control (HR = 0.254; 95 % CI 0.089-0.725; p = 0.010). The prognosis of patients with brain metastases from HCC is dismal even with the modern technology of radiosurgery. The marginal dose prescribed should be reevaluated to improve upon the current poor local control rates.

Assessing Feasibility of Real-Time Ultrasound Monitoring in Stereotactic Body Radiotherapy of Liver Tumors

To monitor tumor motion during stereotactic body radiotherapy (SBRT) for patients with liver cancer, an integrated ultrasound and kilo-voltage cone-beam computed tomography (KV-CBCT) system has been proposed. The presence of an ultrasound probe may interfere with the radiation beams. The purpose of this study is to minimize this interference by altering orientations of the ultrasound probe and directions of radiation beams while not compromising the quality of SBRT plans. Ten patients, who received SBRT of liver cancer, were randomly selected for this study. To simulate the presence of an ultrasound probe, a virtual probe was oriented either parallel or vertical to the longitudinal axis of the patient's body and was added on the surface of the patient's body at the nearest location to the tumor. For both the parallel and vertical probe orientations, 2 new SBRT (Probe-Para and Probe-Vert) plans that minimize the interference between the probe and radiation beams were created for each patient. These SBRT plans were compared to the original clinically accepted SBRT plans, with a treatment goal of 37.5 Gy to the planning target volume (PTV) in 3 fractions. Specific dosimetric endpoints were evaluated, including doses to 95% (D95), of the PTV plan conformal index (CI), homogeneity index (HI), and relevant endpoint doses to organs at risk. For 2 patients with superficially located tumors, no clinically acceptable SBRT plans could be produced without the interference between the probe and radiation beams. For the remaining 8 patients, the Probe-Para plans allowed 7 patients to be treated with coplanar radiation beams (without moving the treatment couch during treatment) and 1 patient to be treated with non-coplanar beams (by moving the treatment couch during treatment). The Probe-Vert plans allowed 2 patients to be treated with coplanar beams and 6 patients to be treated with non-coplanar beams. The average D95 of the PTV were 38.63 Gy ± 0.14 ( p = 0.65) for Probe-Para plans, 38.48 Gy ± 0.31 ( p = 0.33) for Probe-Vert plans, and 38.72 Gy ± 0.14 for clinical SBRT plans. There were no significant differences ( p > 0.05) in CI and HI of all SBRT plans. The endpoint doses to the liver, heart, esophagus, right kidney, and stomach also had no significant differences ( p > 0.05). Except for superficial lesions, real-time ultrasound monitoring during liver SBRT is clinically feasible. Placing the ultrasound probe parallel to the longitudinal axis of the patient allows a greater probability of utilizing preferred coplanar beams.

Effectiveness of stereotactic body radiotherapy for hepatocellular carcinoma with portal vein and/or inferior vena cava tumor thrombosis

BACKGROUND

To report the feasibility, efficacy, and toxicity of stereotactic body radiotherapy (SBRT) for the treatment of portal vein tumor thrombosis (PVTT) and/or inferior vena cava tumor thrombosis (IVCTT) in patients with advanced hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Forty-one patients treated with SBRT using volumetric modulated arc therapy (VMAT) for HCC with PVTT/IVCTT between July 2010 and May 2012 were analyzed. Of these, 33 had PVTT and 8 had IVCTT. SBRT was designed to target the tumor thrombosis and deliver a median total dose of 36 Gy (range, 30-48 Gy) in six fractions during two weeks.

RESULTS

The median follow-up was 10.0 months. At the time of analysis, 15 (36.6%) achieved complete response, 16 (39.0%) achieved partial response, 7 (17.1%) patients were stable, and three (7.3%) patients showed progressive disease. No treatment-related Grade 4/5 toxicity was seen within three months after SBRT. One patient had Grade 3 elevation of bilirubin. The one-year overall survival rate was 50.3%, with a median survival of 13.0 months. The only independent predictive factor associated with better survival was response to radiotherapy.

CONCLUSIONS

VMAT-based SBRT is a safe and effective treatment option for PVTT/IVCTT in HCC. Prospective randomized controlled trials are warranted to validate the role of SBRT in these patients.

Assessing the role of volumetric-modulated arc therapy in hepatocellular carcinoma

The role of volumetric-modulated arc therapy (VMAT) in hepatocellular carcinoma (HCC) remains controversial. The purpose of this study was to determine the potential clinical role of VMAT compared with three-dimensional conformal radiotherapy (3D CRT) for liver irradiation. Four-dimensional CT scans of 24patients with unresectable HCC were included and divided into two groups: (1) adjacent group (n = 11), with planning target volumes overlapping or within 1 cm adjacent to the alimentary tract; (2) nonadjacent group (n = 13), in which the normal liver itself was the dose-limiting structure. Target coverage, organs-at-risk (OARs) doses, delivery parameters, and treatment accuracy were evaluated. Superior target coverage, conformity, and homogeneity were achieved with VMAT compared with 3D CRT. In the adjacent group, VMAT provided superior sparing of serial functioning OARs including the stomach, small intestine, and spinal cord. In the nonadjacent group, VMAT provided inferior sparing of most OARs including the liver, stomach, and small intestine. For the whole group, the effective treatment time was 2.1 ± 0.3 min for 3D CRT and 3.1 ± 0.2 min for VMAT. For liver lesions adjacent to the alimentary tract, this study indicates that VMAT should be selected due to the plan quality, delivery efficiency, and superior sparing of stomach and small intestine. However, for liver lesions away from the alimentary tract, VMAT is not superior to 3D CRT for normal tissue protection.

Sequential phase I and II trials of stereotactic body radiotherapy for locally advanced hepatocellular carcinoma

PURPOSE

To describe outcomes of prospective trials of stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

Two trials of SBRT for patients with active HCC unsuitable for standard locoregional therapies were conducted from 2004 to 2010. All patients had Child-Turcotte-Pugh class A disease, with at least 700 mL of non-HCC liver. The SBRT dose range was 24 to 54 Gy in six fractions. Primary end points were toxicity and local control at 1 year (LC1y), defined as no progressive disease (PD) of irradiated HCC by RECIST (Response Evaluation Criteria in Solid Tumors).

RESULTS

A total of 102 patients were evaluable (Trial 1, 2004 to 2007: n = 50; Trial 2, 2007 to 2010: n = 52). Underlying liver disease was hepatitis B in 38% of patients, hepatitis C in 38%, alcohol related in 25%, other in 14%, and none in 7%. Fifty-two percent received prior therapies (no prior sorafenib). TNM stage was III in 66%, and 61% had multiple lesions. Median gross tumor volume was 117.0 mL (range, 1.3 to 1,913.4 mL). Tumor vascular thrombosis (TVT) was present in 55%, and extrahepatic disease was present in 12%. LC1y was 87% (95% CI, 78% to 93%). SBRT dose (hazard ratio [HR] = 0.96; P = .02) and being in Trial 2 (HR = 0.38; P = .03) were associated with LC1y on univariate analysis. Toxicity ≥ grade 3 was seen in 30% of patients. In seven patients (two with TVT PD), death was possibly related to treatment (1.1 to 7.7 months after SBRT). Median overall survival was 17.0 months (95% CI, 10.4 to 21.3 months), for which only TVT (HR = 2.47; P = .01) and being in Trial 2 (HR = 0.49; P = .01) were significant on multivariate analysis.

CONCLUSION

These results provide strong rationale for studying SBRT for HCC in a randomized trial.

Radiotherapy with volumetric modulated arc therapy for hepatocellular carcinoma patients ineligible for surgery or ablative treatments

PURPOSE

The aim of this article is to report the dosimetric and clinical findings in the treatment of primary hepatocellular carcinoma (HCC) with volumetric modulated arc therapy (VMAT, RapidArc).

METHODS AND MATERIALS

A total of 138 patients were investigated. Dose prescription ranged from 45-66 Gy. Most patients (88.4 %) presented AJCC stage III or IV and 83 % were N0-M0. All were classified as Barcelona Clinic Liver Cancer (BCLC) stage A-C. All patients were treated using 10 MV photons with single or multiple, coplanar or non-coplanar arcs, and cone-down technique in case of early response of tumors.

RESULTS

The patients' median age was 66 years (range 27-87 years), 83 % were treated with 60 Gy (12 % at 45 Gy, 6 % at 66 Gy), 62 % with cone-down, 98 % with multiple arcs. The mean initial planning target volume (PTV) was 777 ± 632 cm(3); the mean final PTV (after the cone-down) was 583 ± 548 cm(3). High target coverage was achieved. The final PTV was V98% > 98 %. Kidneys received on average 5 and 8 Gy (left and right), while the maximum dose to the spinal cord was 22 Gy; mean doses to esophagus and stomach were 23 Gy and 15 Gy, respectively. The average volume of healthy liver receiving more than 30 Gy was 294 ± 145 cm(3). Overall survival at 12 months was 45 %; median survival was 10.3 months (95 % confidence interval 7.2-13.3 months). Actuarial local control at 6 months was 95 % and 93.7 % at 12 months. The median follow-up was 9 months and a maximum of 28 months.

CONCLUSION

This study showed from the dosimetric point of view the feasibility and technical appropriateness of RapidArc for the treatment of HCC. Clinical results were positive and might suggest, with appropriate care, to consider RapidArc as an additional therapeutic opportunity for these patients.

Radiation treatment with volumetric modulated arc therapy of hepatocellular carcinoma patients. Early clinical outcome and toxicity profile from a retrospective analysis of 138 patients

Background

To report early outcome and toxicity for inoperable patients with hepatocellular carcinoma (HCC) treated with volumetric modulated arc therapy (VMAT).

Methods

One hundred and thirty eight patients were retrospectively analysed. Dose prescription ranged from 45 to 66Gy with conventional fractionation regime. Based on AJCC staging, 88.4% presented stage III or IV. Two-thirds (69.6%) were Child-Pugh stage A, the remaining were stage B. According to Barcelona Clinic Liver Cancer staging, 72.5% of patients were classified as stage C.

Results

Median age was 66 years, median tumor volume was 516cm³ (28 to 3620cm³). The most patients (83%) were treated with 60Gy. Median follow-up time was 9 months. One-year overall survival rate was 45% (100% for AJCC stage I, 83% for stage II, 45% for stage III and 28% for stage IV), median survival was 10.3 months (95% C.I. 7.2-13.3). Local control was achieved in 94% (of 109 assessable patients), stable disease in 29%, partial response in 53%, complete response in 11%, and progression in 6%. Radiation-induced liver disease was observed in 34 patients (25%). Gastrointestinal grade 3 toxicity was modest with a total of 17 (12.3%) cases for all endpoints.

Conclusions

Clinical results could suggest to introduce VMAT as an appropriate technique for the patients with HCC.

Long-term outcomes of stereotactic body radiation therapy in the treatment of hepatocellular cancer as a bridge to transplantation

Hepatocellular carcinoma (HCC) is potentially curable with hepatic resection or transplantation. Few patients are eligible for resection, and many face a long wait for donor organ availability for liver transplantation. Here we report the safety and efficacy of stereotactic body radiation therapy (SBRT), the explant pathology findings and survival of patients treated with SBRT as a bridge to transplantation for HCC. From April 2005 to August 2010, 10 patients with 11 HCCs were treated with SBRT as a bridge to transplantation. All patients were evaluated by a liver transplant surgeon before radiosurgery. SBRT was delivered with the CyberKnife robotic radiosurgery system. After SBRT, all patients underwent orthotopic liver transplantation. The tumor response was determined by explant pathology. The median follow-up was 62 months from the time of SBRT. The mean time on the liver transplant wait list was 163 days. The median tumor size was 3.4 cm (range = 2.5-5.5 cm). The median SBRT dose was 51 Gy (range = 33-54 Gy) in 3 fractions. The median time from SBRT to liver transplantation was 113 days (range = 8-794 days). At 5 years, the overall survival rate and the disease-free survival rate were both 100%. Overall, 4 of the 10 patients (40%) experienced acute toxicity. Most toxicities were grade 1, and they included nausea, fatigue, and abdominal discomfort. One patient had grade 2 nausea/vomiting. Explant pathology revealed no viable tumor in 3 of the 11 tumors for a complete response rate of 27%. The remaining 8 tumors decreased or remained stable in size. In conclusion, with a median follow-up over 5 years, we have found that SBRT as a bridge to liver transplantation for HCC is feasible and well tolerated. SBRT for HCC may enable patients to remain on the list for frequently curative transplantation during the wait for organ availability.

Hepatic artery injection of ¹³¹I-labelled metuximab combined with chemoembolization for intermediate hepatocellular carcinoma: a prospective nonrandomized study

PURPOSE

Hepatocellular carcinoma (HCC) is the fifth and seventh most common cause of cancer in men and women, respectively. Transcatheter arterial chemoembolization (TACE) is the standardized therapy for the intermediate stage of HCC. However, the 3-year overall survival remains low (<30 %) in these patients. Thus, there is a critical need for the development of treatment modalities to improve the survival rate. This study aimed to evaluate whether the combination of (131)I-metuximab with chemoembolization could improve treatment efficiency.

METHODS

Between January 2009 and January 2010, a prospective two-arm nonrandomized study was performed in patients with intermediate HCC. Of 138 patients, 68 (combination therapy group) received 132 courses of intraarterial (131)I-metuximab injections combined with chemoembolization (mean 1.94 per patient, median 2, range 1-2), followed by 152 sessions of TACE (mean 2.24 per patient, median 2, range 0-4). The remaining 70 patients (monotherapy group) received 296 sessions of TACE (mean 4.23 per patient, median 4, range 1-7).

RESULTS

The overall median survival times for the combination therapy group and the group treated only with TACE were 26.7 months (95 % CI 20.7-31.3 months) and 20.6 months (95 % CI 15.3-24.7 months), respectively. The combination therapy group had a significantly higher survival rate than the TACE-only group (P = 0.038). Age ≥65 years, serum albumin ≤35 g/l, and treatment category (combination therapy or TACE only) were independent prognostic factors for survival according to multivariate analysis.

CONCLUSION

The combination of (131)I-metuximab and chemoembolization extended survival in patients with intermediate HCC compared with TACE only, and was well tolerated by patients with Child-Pugh class A or B disease. This combination seems to be a promising treatment modality for patients with intermediate HCC.