Management of hepatic metastases

Precision dosimetry in yttrium-90 radioembolization through CT imaging of radiopaque microspheres in a rabbit liver model

PURPOSE

To perform precision dosimetry in yttrium-90 radioembolization through CT imaging of radiopaque microspheres in a rabbit liver model and to compare extracted dose metrics to those produced from conventional PET-based dosimetry.

MATERIALS AND METHODS

A CT calibration phantom was designed containing posts with nominal microsphere concentrations of 0.5 mg/mL, 5.0 mg/mL, and 25.0 mg/mL. The mean Hounsfield unit was extracted from the post volumes to generate a calibration curve to relate Hounsfield units to microsphere concentration. A nominal bolus of 40 mg of microspheres was administered to the livers of eight rabbits, followed by PET/CT imaging. A CT-based activity distribution was calculated through the application of the calibration curve to the CT liver volume. Post-treatment dosimetry was performed through the convolution of yttrium-90 dose-voxel kernels and the PET- and CT-based cumulated activity distributions. The mean dose to the liver in PET- and CT-based dose distributions was compared through linear regression, ANOVA, and Bland-Altman analysis.

RESULTS

A linear least-squares fit to the average Hounsfield unit and microsphere concentration data from the calibration phantom confirmed a strong correlation (r2 > 0.999) with a slope of 14.13 HU/mg/mL. A poor correlation was found between the mean dose derived from CT and PET (r2 = 0.374), while the ANOVA analysis revealed statistically significant differences (p < 10-12) between the MIRD-derived mean dose and the PET- and CT-derived mean dose. Bland-Altman analysis predicted an offset of 15.0 Gy between the mean dose in CT and PET. The dose within the liver was shown to be more heterogeneous in CT than in PET with an average coefficient of variation equal to 1.99 and 1.02, respectively.

CONCLUSION

The benefits of a CT-based approach to post-treatment dosimetry in yttrium-90 radioembolization include improved visualization of the dose distribution, reduced partial volume effects, a better representation of dose heterogeneity, and the mitigation of respiratory motion effects. Post-treatment CT imaging of radiopaque microspheres in yttrium-90 radioembolization provides the means to perform precision dosimetry and extract accurate dose metrics used to refine the understanding of the dose-response relationship, which could ultimately improve future patient outcomes.

Single-centre survival analysis over 10 years after MR-guided radiofrequency ablation of liver metastases from different tumour entities

Background

Radiofrequency ablation (RFA) is a minimal-invasive, local therapy in patients with circumscribed metastatic disease. Although widely used, long time survival analysis of treated liver metastases is still pending while also analysing the patients’ experience of MR-based radiofrequency.

Methods

Monocentric, retrospective analysis of long-time overall and progression free survival (OS; PFS) of 109 patients, treated with MRI-guided hepatic RFA between 1997 and 2010, focusing on colorectal cancer patients (CRC). Complimentary therapies were evaluated and Kaplan Meier-curves were calculated. Patients’ experience of RFA was retrospectively assessed in 28 patients.

Results

1-, 3-, 5-, 10-year OS rates of 109 patients with different tumour entities were 83.4%, 53.4%, 31.0% and 22.9%, median 39.2 months, with decreasing survival rates for larger metastases size. For 72 CRC patients 1-, 3-, 5-, 10-year OS rates of 90.2%, 57.1%, 36.1% and 26.5% were documented (median 39.5 months). Thereof, beneficial outcome was detected for patients with prior surgery of the CRC including chemotherapy (median 53.0 months), and for liver metastases up to 19 mm (28.5% after 145 months). Hepatic PFS was significantly higher in patients with liver lesions up to 29 mm compared to larger ones (p = 0.035). 15/28 patients remembered RFA less incriminatory than other applied therapies.

Conclusions

This is the first single-centre, long-time OS and PFS analysis of MRI-guided hepatic RFA of liver metastases from different tumour entities, serving as basis for further comparison studies. Patients’ experience of MR based RFA should be analysed simultaneously to the performed RFA in the future.

Non-invasive detection and complementary diagnosis of liver metastases via chemokine receptor 4 imaging

Noninvasive detection of early-stage liver metastases from different primary cancers is a pressing unmet medical need. The lack of both molecular biomarkers and the sensitive imaging methodology makes the detection challenging. In this study, we observed the elevated expression of chemokine receptor 4 (CXCR4) in uveal melanoma (UM) patient liver tissues, and high CXCR4 expression in liver metastases of UM murine models, regardless of the expression levels in the primary tumors. Based on these findings, we identified CXCR4 as an imaging biomarker and exploited a CXCR4-targeted MRI contrast agent ProCA32.CXCR4 for molecular MRI imaging. ProCA32.CXCR4 has strong CXCR4 binding affinity, high metal selectivity, and r1 and r2 relaxivities, which enables the sensitive detection of liver micrometastases. The MRI imaging capacity for detecting liver metastases was demonstrated in three UM models and one ovarian cancer model. The imaging results were validated by histological and immunohistochemical analysis. ProCA32.CXCR4 has strong potential clinical application for non-invasive diagnosis of liver metastases.

Bleeding Liver Masses: Imaging Features With Pathologic Correlation and Impact on Management

OBJECTIVE. The purposes of this article are to discuss a variety of liver masses that can present with hemorrhage, including their characteristic imaging features, and to propose a diagnostic approach. CONCLUSION. A broad spectrum of pathologic conditions can present as spontaneous hemorrhage within or surrounding the liver and may present acutely or as a chronic or incidental finding. Imaging characteristics and clinical history can often narrow the differential diagnosis and guide management.

The emerging role of stereotactic radiotherapy in gastrointestinal malignancies: a review of the literature and analysis from the Irish perspective

Primary and secondary malignancies of the liver and pancreas result in significant morbidity and mortality, with increasing incidence and increasing demands on health services worldwide. Surgery is the only curative single modality of treatment and remains the gold standard. Unfortunately, up to 80% of the patients present with unresectable disease, and so, alternative efficacious local and systemic treatments are needed. Technologic advances in radiotherapy over recent decades have meant that precision high-dose treatment with stereotactic body radiotherapy (SBRT) has emerged as a viable cost-effective outpatient-based treatment in the management of these difficult to treat abdominal malignancies. This article reviews the current indications for SBRT in these settings, comparing it with other treatments including surgery, chemotherapy, radiofrequency ablation, and trans-arterial chemoembolisation. We also review the current use of abdominal SBRT and future projections in the Irish healthcare setting.

Research and Development of Atractylodes lancea (Thunb) DC. as a Promising Candidate for Cholangiocarcinoma Chemotherapeutics

Treatment and control of cholangiocarcinoma (CCA): the bile duct cancer is limited by the lack of effective chemotherapeutic drugs and alternative drugs are needed, particularly those from natural sources. This article reviews steps of research and development of Atractylodes lancea (Thunb) DC. (AL) as potential candidate for CCA chemotherapy, with adoption of the reverse pharmacology approach. Major steps include (1) reviewing of existing information on its phytochemistry and pharmacological properties, (2) screening of its activities against CCA, (3) standardization of AL, (4) nonclinical studies to evaluate anti-CCA activities, (5) phytochemistry and standardization of AL extract, (6) development of oral pharmaceutical formulation of standardized AL extract, and (7) toxicity testing of oral pharmaceutical formulation of standardized AL extract. Results from a series of our study confirm anti-CCA potential and safety profiles of both the crude extract and the finished product (oral pharmaceutical formulation of the standardized AL extract). Phases I and II clinical trials of the product to confirm tolerability and efficacy in healthy subjects and patients with advanced stage CCA will be carried out soon.

The Liver in Oncology

Gastroenterologists and hepatologists will encounter oncology patients who develop abnormal liver tests, patients with hepatic malignancies, and patients with acute and chronic liver disease who require chemotherapy or immediate evaluation. Chemotherapy can cause liver injury owing to toxic effects or idiosyncratic reactions. Immune checkpoint inhibitors may be associated with autoimmune-mediated liver toxicities. Venoocclusive disease requires immediate evaluation. Nodular regenerative hyperplasia is a chronic progressive disorder. Screening and prophylaxis for reactivation of hepatitis B is important to minimize complications in patients receiving chemotherapy. Patients with metastatic lesions can undergo resection or ablation. Hepatic injury may occur in those receiving radiation-based therapies.

Hepatic Metastasis from Colorectal Cancer

The liver is the most common site of metastasis in patients with colorectal cancer due to its anatomical situation regarding its portal circulation. About 14 to 18% of patients with colorectal cancer present metastasis at the first medical consultation, and 10 to 25% at the time of the resection of the primary colorectal cancer. The incidence is higher (35%) when a computed tomography (CT) scan is used.

In the last decades, a significant increase in the life expectancy of patients with colorectal cancer has been achieved with different diagnostic and treatment programs. Despite these improvements, the presence of metastasis, disease recurrence, and advanced local tumors continue to remain poor prognostic factors.

Median survival without treatment is <8 months from the moment of its presentation, and a survival rate at 5 years of 11% is the best prognosis for those who present with local metastasis. Even in patients with limited metastatic disease, 5-year survival is exceptional. Patients with hepatic metastasis of colorectal cancer have a median survival of 5 to 20 months with no treatment. Approximately 20 to 30% of patients with colorectal metastasis have disease confined to the liver, and this can be managed with surgery. Modern surgical strategies at the main hepatobiliary centers have proved that hepatectomy of 70% of the liver can be performed, with a mortality rate of <5%.

It is very important to have knowledge of predisposing factors, diagnostic methods, and treatment of hepatic metastasis. However, the establishment of newer, efficient, preventive screening programs for early diagnosis and adequate treatment is vital.

How to cite this article: Valderrama-Treviño AI, Barrera-Mera B, Ceballos-Villalva JC, Montalvo-Javé EE. Hepatic Metastasis from Colorectal Cancer. Euroasian J Hepato-Gastroenterol 2017;7(2):166-175.

Survival Outcomes for Patients With Indeterminate 18FDG-PET Scan for Extrahepatic Disease Before Liver Resection for Metastatic Colorectal Cancer: A Retrospective Cohort Study Using a Prospectively Maintained Database to Analyze Survival Outcomes for Patients With Indeterminate Extrahepatic Disease on 18FDG-PET Scan Before Liver Resection for Metastatic Colorectal Cancer

OBJECTIVE

The aim of this study was to evaluate overall survival (OS) and cancer recurrence for patients with indeterminate positron emission tomography (PET) scan for extrahepatic disease (EHD) before liver resection (LR) for colorectal liver metastases (CLMs).

SUMMARY OF BACKGROUND DATA

Indeterminate EHD as determined by PET imaging indicates a probability of extrahepatic malignancy and potentially excludes patients from undergoing LR for CLM.

METHODS

In a retrospective analysis of prospectively collected data from February 2006 to December 2014, OS for patients with indeterminate EHD on FDG-PET scan before LR for CLM was performed using standard survival analysis methods, including Kaplan-Meier estimator and Cox proportional hazard models for multivariate analyses. Postoperative imaging was used as reference to evaluate the association between indeterminate EHD and recurrence.

RESULTS

Of 267 patients with PET scans before LR, 197 patients had no EHD and 70 patients had indeterminate EHD. Median follow-up was 33 months. The estimated 5-year OS was 60.8% versus 59.4% for indeterminate and absent EHD, respectively (P = 0.625). Disease-free survival was comparable between both groups (P = 0.975) and overall recurrence was 57.1% and 59.5% for indeterminate and absent EHD, respectively (P = 0.742). About 16.9% of recurrence was associated with the site of indeterminate EHD, with 80% of associated recurrence occurring in the thorax.

CONCLUSIONS

The site of indeterminate EHD appears to have a predictive value for recurrence, with indeterminate EHD in the thorax having a higher probability of malignancy. The evidence in this report supports the critical evaluation of PET scan results and that patients are not denied potential curative LR unless the evidence for unresectable EHD is certain.

Precision Medicine and Non-Colorectal Cancer Liver Metastases: Fiction or Reality?

BACKGROUND

Non-colorectal liver metastases (nCRLM) constitute a variety of heterogeneous diseases and a considerable therapeutic challenge. Management is based on the primary tumor and the clinical course. In the era of precision medicine (PM) we know that cancer is heterogeneous within the tumor and across different sites.

METHODS

We give an overview of the path to PM through 'omics' beyond genomics. We refer to the experience gained to date from models such as colorectal cancer and we discuss the opportunity offered by PM for the management of nCRLM.

RESULTS

In order to best characterize and track tumor biological behaviors as well as to understand mechanisms of response to therapy and survival we suggest the application of novel clinical trial designs, a dynamic approach with serial monitoring involving evaluation of primary and metastatic sites. Quality and standardization of tissue acquisition and biobanking is a precondition for the reliability of this approach.

CONCLUSION

The application of PM is increasingly becoming a reality. Elucidating the mysteries of tumors in complex settings can only be achieved with the approach PM offers. nCRLM may serve as a model for the application of PM principles and techniques in understanding individual diseases and also cancer as an entity and therapeutic challenge.

Neoadjuvant TACE before laser induced thermotherapy (LITT) in the treatment of non-colorectal non-breast cancer liver metastases: feasibility and survival rates

PURPOSE

To evaluate safety, feasibility and overall survival rates for transarterial chemoembolization (TACE) alone or combined with MR-guided laser-induced-thermotherapy (LITT) in liver metastases of non-colorectal and non-breast cancer origin.

METHODS AND MATERIALS

Included were patients with unresectable non-colorectal non-breast cancer liver metastases with progression under systemic chemotherapy. Excluded were patients with Karnofsky score ≤ 70, respiratory, renal and cardiovascular failure, and general TACE contraindications. TACE using Mitomycin alone, Mitomycin-Gemcitabine or Mitomycin-Gemcitabine-Cisplatin was performed to all patients. After TACE 146 metastases were ablated with MR-guided LITT. To be eligible for LITT metastases should be < 5 cm in size and ≤ 5 in number. Tumor response was evaluated using MRI according to RECIST. Survival was evaluated using Kaplan-Meier analysis.

RESULTS

A total of 110 patients (mean age 59.2 years) with 371 metastases received TACE (mean 5.4 sessions/patient, n=110) with 76 (69%) receiving LITT (mean 1.6 session/patient) afterwards. TACE resulted in a mean decrease of mean maximum diameter of 52% ± 26.6 and volume change of -68.5% ± 22.9 in the 25 patients (23%) with partial response. Stable disease (n=59, 54%). Progressive disease (n=26, 23%). The RECIST outcome after LITT showed complete response (n=13, 17%), partial response (n=1, 1%), stable situation (n=41, 54%) and progressive disease (n=21, 28%). The mean time to progression (TTP) was 8.6 months. Median survival of all patients was 21.1 months.

CONCLUSION

TACE with different protocols alone and in combination with LITT is a feasible palliative treatment option resulting in a median survival of 21.1 months for unresectable liver metastases of non-colorectal and non-breast cancer origin.

Synchronous resection of colorectal cancer and liver metastases: comparative views of colorectal and liver surgeons

AIM

The optimal management of patients presenting with colorectal cancer and synchronous liver metastases is controversial. This survey was intended to summarize the opinions of UK colorectal and liver surgeons on the specific issues pertaining to synchronous resection.

METHOD

A validated electronic survey was sent to the consultant members of the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and the Association of Upper Gastrointestinal Surgeons (AUGIS). The questions were structured to allow direct comparison between the two groups of the responses obtained.

RESULTS

Four hundred and twenty-four specialist colorectal surgeons and 52 specialist hepatobiliary surgeons were identified from the register of their respective associations. Responses were obtained from 133 (31%) colorectal and 22 (42%) liver surgeons. A majority of both groups of surgeons felt that synchronous resection was a valid therapeutic option. A majority of both groups believed that synchronous resection was justified despite the options of laparoscopic surgery and enhanced recovery programmes for each discipline. Agreed possible advantages of synchronous resections were: a decrease in the overall length of hospital stay, cost and patient anxiety. The major concern about synchronous resections was an excessive overall physiological insult. Specific scenarios indicated that synchronous resection was favoured for major/complex major colorectal resection with minor liver resection or most colorectal resections not involving an anastomosis with either a minor or major liver resection.

CONCLUSION

Although significant concerns relating to synchronous resection remain amongst colorectal and liver surgeons, a majority of them felt that synchronous resections could be offered to appropriately selected patients.

Holmium-166 radioembolization for the treatment of patients with liver metastases: design of the phase I HEPAR trial

BACKGROUND

Intra-arterial radioembolization with yttrium-90 microspheres ( 90Y-RE) is an increasingly used therapy for patients with unresectable liver malignancies. Over the last decade, radioactive holmium-166 poly(L-lactic acid) microspheres ( 166Ho-PLLA-MS) have been developed as a possible alternative to 90Y-RE. Next to high-energy beta-radiation, 166Ho also emits gamma-radiation, which allows for imaging by gamma scintigraphy. In addition, Ho is a highly paramagnetic element and can therefore be visualized by MRI. These imaging modalities are useful for assessment of the biodistribution, and allow dosimetry through quantitative analysis of the scintigraphic and MR images. Previous studies have demonstrated the safety of 166Ho-PLLA-MS radioembolization ( 166Ho-RE) in animals. The aim of this phase I trial is to assess the safety and toxicity profile of 166Ho-RE in patients with liver metastases.

METHODS

The HEPAR study (Holmium Embolization Particles for Arterial Radiotherapy) is a non-randomized, open label, safety study. We aim to include 15 to 24 patients with liver metastases of any origin, who have chemotherapy-refractory disease and who are not amenable to surgical resection. Prior to treatment, in addition to the standard technetium-99m labelled macroaggregated albumin ( 99mTc-MAA) dose, a low radioactive safety dose of 60-mg 166Ho-PLLA-MS will be administered. Patients are treated in 4 cohorts of 3-6 patients, according to a standard dose escalation protocol (20 Gy, 40 Gy, 60 Gy, and 80 Gy, respectively). The primary objective will be to establish the maximum tolerated radiation dose of 166Ho-PLLA-MS. Secondary objectives are to assess tumour response, biodistribution, performance status, quality of life, and to compare the 166Ho-PLLA-MS safety dose and the 99mTc-MAA dose distributions with respect to the ability to accurately predict microsphere distribution.

DISCUSSION

This will be the first clinical study on 166Ho-RE. Based on preclinical studies, it is expected that 166Ho-RE has a safety and toxicity profile comparable to that of 90Y-RE. The biochemical and radionuclide characteristics of 166Ho-PLLA-MS that enable accurate dosimetry calculations and biodistribution assessment may however improve the overall safety of the procedure.

A phase I study of hyperthermic isolated hepatic perfusion with oxaliplatin in the treatment of unresectable liver metastases from colorectal cancer

Isolated hepatic perfusion (IHP) is a proven approach for regional delivery of chemotherapy in patients with unresectable primary and metastatic tumors of the liver. Most trials of IHP have utilized melphalan as the active drug in the perfusate. We performed a phase I trial to evaluate the efficacy, safety, and maximum tolerated dose (MTD) of oxaliplatin delivered by hyperthermic isolated hepatic perfusion. A phase I dose-escalation trial of hyperthermic IHP with oxaliplatin in patients with unresectable metastatic colorectal cancer scheduled to undergo placement of a hepatic arterial infusion (HAI) pump was carried out. Thirteen patients were enrolled between November 2003 and September 2006. Dose-limiting veno-occlusive disease was observed at 60 mg/m(2). At the MTD of 40 mg/m(2) only minor transient liver dysfunction was observed. Ultrafilterable platinum area under the curve and maximum concentration delivered by IHP increased nonlinearly with dose as did platinum concentrations in liver biopsies obtained at the end of the 60 min IHP. Seventy-seven percent of patients had a >50% decrease in serum carcinoembryonic antigen (CEA) after IHP. The overall response rate to the combined IHP and HAI therapy was 66%. One patient had a durable complete response (>4 years). We conclude that hyperthermic IHP with oxaliplatin was safe and feasible at a dose of 40 mg/m(2). The ability to obtain complete vascular isolation with open IHP was confirmed. The response rate in this small phase I study was encouraging.

Selective inhibition of proprotein convertases represses the metastatic potential of human colorectal tumor cells

The proprotein convertases (PCs) are implicated in the activation of various precursor proteins that play an important role in tumor cell metastasis. Here, we report their involvement in the regulation of the metastatic potential of colorectal tumor cells. PC function in the human and murine colon carcinoma cell lines HT-29 and CT-26, respectively, was inhibited using siRNA targeting the PCs furin, PACE4, PC5, and PC7 or by overexpression of the general PC inhibitor alpha1-antitrypsin Portland (alpha1-PDX). We found that overexpression of alpha1-PDX and knockdown of furin expression inhibited processing of IGF-1 receptor and its subsequent activation by IGF-1 to induce IRS-1 and Akt phosphorylation, all important in colon carcinoma metastasis. These data suggest that the PC furin is a major IGF-1 receptor convertase. Expression of alpha1-PDX reduced the production of TNF-alpha and IL-1alpha by human colon carcinoma cells, and incubation of murine liver endothelial cells with conditioned media derived from these cells failed to induce tumor cell adhesion to activated murine endothelial cells, a critical step in metastatic invasion. Furthermore, colon carcinoma cells in which PC activity was inhibited by overexpression of alpha1-PDX when injected into the portal vein of mice showed a significantly reduced ability to form liver metastases. This suggests that inhibition of PCs is a potentially promising strategy for the prevention of colorectal liver metastasis.

Surveillance of patients following surgery with curative intent for colorectal cancer

Surveillance after resection of colorectal cancer with curative intent is an important component of post-operative care. Clinical review, imaging, colonoscopy, and cost to the community are among significant issues to consider in planning a surveillance regime. This review aims to identify the available evidence for the use of surveillance and its individual components. The literature pertaining to follow-up of patients following potentially curative surgery for colorectal cancer was reviewed in order to formulate a summary of the wide range of clinical practice. There is evidence of improved survival of patients undergoing more intense follow-up compared with those having minimal surveillance, with an estimated overall 5-year gain of up to 10%. The efficacy of individual components of follow-up regimes remains unclear, but an overall package of ‘intensive’ follow-up including clinical review, liver imaging, and colonoscopy appears to be of benefit. It is cost-effective and can be specialist or community-based.

Radiofrequency ablation (RFA): development of a flow model for bovine livers for extensive bench testing

PURPOSE

To develop a flow model for bovine livers for extensive bench testing of technical improvements or procedure-related developments of radiofrequency ablation excluding animal experiments.

METHODS

The perfusion of bovine livers directly from the slaughterhouse was simulated in a liver perfusion tank developed for the experimental work. The liver perfusion medium used was a Tyrode solution prepared in accordance with physiologic criteria (as for liver transplants) which was oxygenated by an oxygenator and heated to 36.5 degrees C. Portal vein circulation was regulated via a flow- and pressure-controlled pump and arterial circulation using a dialysis machine. Flow rate and pressure were adjusted as for the physiology of a human liver converted to bovine liver conditions. The fluid discharged from the liver was returned into the perfusion system through the vena cava. Extendable precision swivel arms with the radiofrequency probe attached were mounted on the liver perfusion tank. RFA was conducted with the RF3000 generator and a 2 cm LeVeen needle (Boston Scientific, Ratingen, Germany) in a three-dimensional grid for precise localization of the generated thermolesions.

RESULTS

Four bovine livers weighing 8.4 +/- 0.4 kg each were prepared, connected to the perfusion system, and consecutively perfused for the experiments. Mean arterial flow was 569 +/- 43 ml/min, arterial pressure 120 mmHg, portovenous flow 1440 +/- 305 ml/min, and portal pressure 10 mmHg. Macroscopic evaluation after the experiments revealed no thrombi within the hepatic vessels. A total of 136 RF thermolesions were generated with an average number of 34 per liver. Mean RF duration was 2:59 +/- 2:01 min:sec with an average baseline impedance of 28.2 +/- 3.4 ohms. The mean diameter of the thermolesions along the puncture channel was 22.98 +/- 4.34 mm and perpendicular to the channel was 23.27 +/- 4.82 mm.

CONCLUSION

Extracorporeal perfusion of bovine livers with consecutive standardized RF ablation was feasible. The bovine liver flow model seems to allow extensive, standardized evaluation of technical or procedure-related developments of RF systems.

Synergistic antitumor effects of histamine plus melphalan in isolated hepatic perfusion for liver metastases

BACKGROUND

Nonresectable primary and metastatic liver tumors remain an important clinical problem. Melphalan-based isolated hepatic perfusion (M-IHP) leads to more than 70% objective responses in selective groups of patients with nonresectable metastases confined to the liver. Complete responses are rare and progression-free survival is limited. Tumor necrosis factor (TNF), a very active agent in isolated limb perfusion, is linked to serious hepatotoxicity, restricting its use in IHP. Because of its vasoactive properties, histamine (Hi) is an alternative to TNF. In this article we evaluate its potential synergistic effect in M-IHP, improving response rates.

METHODS

Our experimental rat IHP model is used for the treatment of soft tissue sarcoma liver metastases. Blood samples are collected for monitoring liver enzymes. Livers are excised 72 h and 7 days after treatment for histologic evaluation.

RESULTS

After sham-IHP and Hi-IHP, tumor progression was observed in 100% of treated animals, while after M-IHP this number fell to 62% and after Hi + M-IHP it fell to only 22% (P = 0.006). Overall response rates were of 55% for Hi + M-IHP vs. 25% for M-IHP, and, more importantly, complete responses (CR) were observed only after Hi + M-IHP (22%) (P = 0.009). Hepatotoxicity peaked within 24 h after IHP, independent of the treatment administered, recovered in 48 h, and was related mainly to the elevation of transaminases (grade 3 ASAT and grade 1 ALAT for control group and grades 3 and 4, respectively, for all other treatments). No serious systemic toxicity was observed. Histology of the liver showed no serious damage.

CONCLUSION

Hi + M-IHP has synergistic antitumor effects without any increase in regional or systemic toxicity.

Bio-chemotherapeutic strategies and the (dis) utility of hypoxic perfusion of liver, abdomen and pelvis using balloon catheter techniques

AIMS

To review the development and current status of balloon catheter mediated hypoxic perfusion of abdomen, pelvis and liver for treatment of locally advanced malignancies. Within this context we focus on the addition of tumour necrosis factor-alpha (TNF) to these minimal invasive perfusion procedures.

METHODS

A literature search on these topics was carried out in PubMed for indexed articles and in all issues of Regional Cancer Treatment. The findings were related to our own experiences.

RESULTS

Hypoxic abdominal (HAP) and hypoxic pelvic perfusion (HPP) using balloon catheters, are currently applied modalities for treatment of a wide variety of abdominal and pelvic tumours, yet scientific validation of these procedures is poor. Following the results of several Phase I-II trials, both treatments are associated with severe systemic toxicity, significant morbidity and even mortality. The degree of systemic leakage associated with these procedures prohibits addition of TNF. For leakage free liver perfusion surgery is still required, as with current balloon catheter techniques it is not possible to perform leakage free isolated hypoxic hepatic perfusion (IHHP), using either orthograde or retrograde hepatic flow. Experimental and clinical observations suggest that within any perfusion setting, the utilization of TNF is only indicated for treatment of highly vascularised tumours and not for treatment of colorectal tumours.

CONCLUSION

Balloon catheter technology in its present form does not provide adequate leakage control in any of these settings and is therefore associated with considerable toxicity. It is associated with poor response rates and cannot be considered in any setting as a standard of care.

Assessment of staging, prognosis and mortality of colorectal cancer by tumor markers: receptor erbB-2 and cadherins

PURPOSE

To evaluate the prognostic significance and correlation with staging and degree of cell differentiation of the tumoral expression of the proteins c-erbB-2 and E-cadherin, in patients with colorectal adenocarcinoma.

METHODS

The study included 117 patients with an average age of 63.1 years and an average follow-up duration of 28.1 months. The disease-free interval, survival, incidence of recurrence and specific mortality were evaluated. c-erbB-2 anti-oncoprotein antibodies (Dako) were utilized via the streptavidin-biotin technique. Samples were considered to be positive for c-erbB-2 if 10% or more of the tumor cell membranes were stained. The anti-E-cadherin antibodies (Dako), evaluated this protein and is considered positive, if 50% or more of the cell membranes were stained. Statistical analysis was performed using Pearson's chi-squared test, Fisher's exact test, Kaplan-Meier's estimator, the log-rank test and Wilcoxon's test (Breslow version), setting the level of statistical significance at 5% (p<0.05).

RESULTS

52 of 108 patients studied for c-erbB-2 were positive (48.1%), 47 of 93 patients studied for E-cadherin were negative (50.5%). These data do not express any correlation with TNM (tumor, node and metastasis) staging and the degree of cell differentiation or with the tumor recurrence rate. The disease-free interval among patients who were positive for c-erbB-2 and negative for E-cadherin was 68.0 months and did not differ from those with c-erbB-2 negative and E-cadherin positive (55.0 months--p = 0.5510). The average survival among patients positive for c-erbB-2 and negative for E-cadherin was 75 months without statistical significance difference with the other group (61 months--p = 0.5256). Specific mortality occurred in 20.0% of the cases and did not correlate with the expression of c-erbB-2 (p=0.446), E-cadherin (p=0.883).

CONCLUSION

The tumoral expression of c-erbB-2 and E-cadherin did not demonstrate a correlation with the staging and degree of cell differentiation, and it did not present prognostic value regarding disease recurrence, disease-free interval, survival and specific mortality among patients with colorectal adenocarcinoma.

Monocyte chemoattractant protein-1 gene delivery enhances antitumor effects of herpes simplex virus thymidine kinase/ganciclovir system in a model of colon cancer

Suicide gene therapy using the herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) system is a well-characterized tool for cancer gene therapy; however, it does not yet exhibit sufficient efficacy to cure patients of malignancies. We have reported that adenovirally delivered monocyte chemoattractant protein (MCP)-1 augmented the antitumor effects of the HSV-tk/GCV system in an athymic nude mouse model. The current study, which uses an immunocompetent mouse model of colon cancer, was designed to evaluate the antitumor effects of MCP-1 gene delivery in conjunction with this suicide gene therapy system. Subcutaneous tumor foci were directly transduced with both recombinant adenoviruses (rAds) expressing an HSV-tk gene and either of the MCP-1, CD80 and LacZ genes, followed by GCV administration. The growth of tumors was markedly suppressed by codelivery of HSV-tk and MCP-1 genes, which was exclusively associated with the recruitment of monocytes/macrophages, T helper 1 (Th1) cytokine gene expression and cytotoxic activity of the splenocytes. Furthermore, the antitumor effects were more efficient than that obtained by the combination of HSV-tk and CD80 genes. These results suggest an immunomodulatory effect of MCP-1 in the context of suicide gene therapy of colon cancer via orchestration of innate and acquired immune responses.

Detection of disseminated tumour cells in the liver of cancer patients

AIMS

The liver is a common site of metastasis from a variety of solid malignancies. This is due to disseminated tumour cells (DTC) that have spread prior to or during surgery from the primary carcinoma. This article gives a short overview of the data published on the detection of DTC in the liver and describes the commonly used detection methods and respective markers.

METHODS

A literature survey was performed in public medical databases comprising the last 15 years with focus on DTC detection in liver tissue of cancer patients.

KEY FINDINGS

Although the liver is a preferred site of metastasis, only a few studies have analysed the DTC incidence in inconspicuous liver tissue. The available reports include only patients with pancreatic and colorectal carcinomas. In patients with pancreatic cancer the DTC incidence varied from 5 to 76%. No follow-up data has been reported so far. In patients with colorectal carcinoma hepatic DTC were found in 5-69% of cases. A negative prognostic influence of hepatic DTC was reported in all but one studies with follow-up information.

CONCLUSIONS

The detection of DTC in the liver can contribute to identify patients with increased risk who could benefit from an intensified follow-up or new treatment strategies.

Radiofrequency ablation in metastatic disease

The liver is the most common site of metastas from colorectal cancer. Hepatic metastases are the major cause of morbidity and mortality in those patients. Surgical resection provides the greatest potential for cure in patients with secondary liver tumors but can be offered to only a small number of patients (5%-20%). In selected patients image-guided radiofrequency ablation (RFA) takes over the role as curative treatment option, especially in patients who are technically not eligible for surgery. Technical aspects, criteria for patient selection, aspects concerning follow-up imaging and results of percutaneous radiofrequency ablation in liver metastases from colorectal cancer are discussed.

Isolated hypoxic hepatic perfusion with orthograde or retrograde flow in patients with irresectable liver metastases using percutaneous balloon catheter techniques: a phase I and II study

BACKGROUND

Isolated hepatic perfusion for irresectable metastases confined to the liver has reported response rates of 50% to 75%. Magnitude, costs, and nonrepeatability of the procedure are its major drawbacks. We developed a less invasive, less costly, and potentially repeatable balloon catheter-mediated isolated hypoxic hepatic perfusion (IHHP) technique.

METHODS

In this phase I and II study, 18 consecutive patients with irresectable colorectal or ocular melanoma hepatic metastases were included. Two different perfusion methods were used, both with inflow via the hepatic artery, using melphalan 1 mg/kg. In the first eight patients, the portal vein was occluded, and outflow was via the hepatic veins into an intracaval double-balloon catheter. This orthograde IHHP had on average 56% leakage. In next 10 patients, we performed a retrograde outflow IHHP with a triple balloon blocking outflow into the caval vein and allowing outflow via the portal vein. The retrograde IHHP still had 35% leakage on average.

RESULTS

Although local drug concentrations were high with retrograde IHHP, systemic toxicity was still moderate to severe. Partial responses were seen in 12% and stable disease in 81% of patients. The median time to local progression was 4.8 months.

CONCLUSIONS

We have abandoned occlusion balloon methodology for IHHP because it failed to obtain leakage control. We are presently conducting a study using a simplified surgical retrograde IHHP method, in which leakage is fully controlled, which translates into high response rates.

Regional treatment options for patients with ocular melanoma metastatic to the liver

Ocular melanoma is the most common primary ocular malignancy and has a significant predilection for metastasis to the liver. More than 40% of patients have hepatic metastases present at initial diagnosis, and the liver becomes involved in up to 95% of individuals who develop metastatic disease. The median survival of patients after diagnosis of liver metastasis ranges from 2 to 7 months. Metastatic disease localized to the liver has proven to be resistant to most available chemotherapy and immunotherapy regimens. Recognition of the grave prognosis associated with liver metastasis from ocular melanoma has led to the evaluation of new regional treatment modalities primarily designed to control tumor progression in the liver, including hepatic arterial chemotherapy, hepatic artery chemoembolization, regional immunotherapy, isolated hepatic perfusion, and percutaneous hepatic perfusion. This article reviews the efficacy, outcomes, and morbidities of the multiple locoregional therapies available today.

Histologic Evaluation and Treatment Outcome after Sequential Radiofrequency Ablation and Hepatic Resection for Primary and Metastatic Tumors

Operative manipulation during hepatic resection (HR) causes tumor cell shedding which is a factor in disease recurrence. Radiofrequency ablation (RFA) causes coagulative necrosis and was used to destroy the tumor before HR. We evaluated tumor necrosis and recurrence of hepatic malignancies treated by sequential RFA/HR. A retrospective review of patients treated with sequential RFA/HR from April 1999 to January 2002 was performed. A Radionics 500-kW RF generator was used to ablate lesions via H2O-cooled electrodes under ultrasound guidance. Segmental HR was performed after RFA. Resected specimens were reviewed with hematoxylin and eosin staining and for apoptosis. Patient follow-up ranged from 10 to 33 months with evaluation of salient clinical, radiologic, and laboratory parameters. Seven patients (four male and three female) ages 62.1 ± 10.3 years had sequential RFA/HR. Four patients had hepatocellular carcinoma (HCC) and three had colorectal metastases (CRm). The tumors were unifocal right-lobe lesions measuring 4.1 ± 0.9 cm with a resection margin of 0.4 to 2.5 cm. Extensive necrosis was noted but intact nests of tumor cells occurred in all specimens with minimal apoptosis. Three of seven patients (two HCC and one CRm) developed pulmonary metastases at 3 to 20 months with one HCC patient developing concurrent liver metastases. Two deaths occurred in the HCC group. Sequential RFA/HR may minimize local recurrence; however, the high incidence of pulmonary metastases raises concern of transvenous migration. The histologic findings demonstrate foci of intact tumor cells after RFA. Controlled study of additional patients with long-term follow-up is necessary to better understand these findings.

Chemoembolization for hepatic metastases

Liver metastases are one of the most difficult therapeutic challenges in modern oncologic practice. Few systemic therapies are effective for solid tumors in the liver. Resection is possible in a minority of patients and usually not curative. Image-guided therapies such as chemoembolization offer substantial intensification of treatment by combining tumor ischemia, increased drug concentrations, prolonged dwell time, and reduced systemic toxicity. Although not a curative therapy, durable responses are seen in most adenocarcinomas, which may contribute to prolongation and preservation of quality of life by delaying liver failure in patients with liver-dominant disease.

Radiofrequency ablation of hepatic tumors

Radiofrequency thermal ablation is receiving increasing attention as an alternative to standard surgical therapies for the treatment of liver neoplasms. Benefits over surgical resection include the anticipated reduction in morbidity and mortality, low cost, suitability for real time image guidance, the ability to perform ablative procedures on outpatients, and the potential application in a wider spectrum of patients, including nonsurgical candidates. This review examines reported clinical results of this new therapeutic technique, potential complications, current limitations, thermal ablation mechanisms, as well as technical features and diagnostic modalities used in the procedure.

Transarterial perfusion of liver metastases

Progressive growth of unresectable metastatic or primary malignancies confined to the liver is a significant clinical problem. Approximately 25% of patients with colorectal cancer will develop metastatic disease exclusively or largely confined to liver, the vast majority of which are not amenable to surgical resection. Despite aggressive systemic or regional chemotherapy, survival is only 12 to 18 months. More than 80% of patients with ocular melanoma develop liver metastases as the first site of recurrent disease, and death from hepatic disease progression typically occurs 2 to 7 months after diagnosis. In addition, the liver is also the preferred site of metastatic disease for gastrointestinal or pancreatic neuroendocrine tumors. A number of physiological and anatomic features of the liver make it an ideal organ for regionally directed therapy to allow dose intensification to the cancer-burdened area while reducing or eliminating unnecessary systemic toxicity. To that end, complete vascular isolation and perfusion of the liver using a recirculating extracorporeal circuit, also called isolated hepatic perfusion (IHP), has been under clinical evaluation at our institution and others. In this article, we review the current results with IHP and its potential utility in the treatment of patients with unresectable hepatic malignancies.

Local, intrahepatic, and systemic recurrence patterns after radiofrequency ablation of hepatic malignancies

The objective of this study was to describe the recurrence patterns in patients with unresectable hepatic malignancies treated with radiofrequency ablation (RFA). As RFA is applied more widely to patients with hepatic tumors, a better understanding of the biologic behavior of these tumors and the risk of recurrence, both in the liver and systemically, is needed. A multidisciplinary team evaluated patients referred for RFA and followed them prospectively to assess local, intrahepatic, and extrahepatic disease recurrence and complication rates. Forty-five patients with 143 lesions and a minimum follow-up of 6 months (median 19.5 months) were treated. Overall, 7.7% of treated lesions had local recurrence. New intrahepatic disease was seen in 49% of patients, and 24% had evidence of new systemic tumor progression. Patients with colorectal metastatic lesions > or =4 cm at the time of the first RFA were more likely to present with local recurrence (P = 0.048). Complications occurred in 27% of patients. Although RFA has a satisfactory local failure rate and safety profile, the patient population being treated is at high risk of developing new disease. Multimodality adjuvant therapy will be necessary to realize the full potential of hepatic malignancy control with RFA.

Relevance of biologic markers in colorectal carcinoma: a comparative study of a broad panel

BACKGROUND

Although pathologic stage is currently the main prognostic indicator for patients with colorectal carcinoma (CRC), mounting evidence suggests that, in its current form, it is insufficient to predict clinical outcome. To assess biologic markers of primary CRC that may improve clinical staging and provide useful information for the application of novel therapeutic strategies, the authors investigated a panel of markers that included transforming growth factor alpha (TGF alpha), epithelial growth factor receptor (EGF-R; the protein product of the c-erb B2/HER-2 oncogene), matrix metalloproteinase 2 (MMP-2), insulin-like growth factor II (IGF-II), vascular endothelial growth factor (VEGF), and angiogenesis, as evaluated by microvessel density (MVD).

METHODS

Two groups of CRC were studied: 1) surgical samples from patients who achieved a disease free survival of at least 6 years (CRC-M0) and 2) surgical specimens of both primary tumors and synchronous or metachronous liver metastases (CRC-M1).

RESULTS

Chi-square analysis revealed that expression levels of TGF-alpha, c-erb B2/HER-2, MMP-2, IGF-II, VEGF, and MVD (but not EGF-R) were significantly higher in CRC-M1 samples compared with CRC-M0 samples (P < 0.001, P < 0.05, P < 0.001, P < 0.001, P < 0.01, and P < 0.001, respectively). Logistic regression analysis showed that TGF-alpha, IGF-II, and MMP-2 had significantly greater expression in CRC-M1 samples independent of the other variables (including tumor classification, histologic grade, and patient age). If all three markers had > or = 25% expression, then the probability of developing liver metastasis was 99.5%.

CONCLUSIONS

Based on the evidence of this study, TGF-alpha MMP-2, and IGF-II seem suitable candidates for a selective panel of markers designed to provide significant additional information with respect to the current pathologic staging system for patients with colorectal carcinoma.

The impact of new technology on surgery for colorectal cancer

Advances in technology continue at a rapid pace and affect all aspects of life, including surgery. We have reviewed some of these advances and the impact they are having on the investigation and management of colorectal cancer. Modern endoscopes, with magnifying, variable stiffness and localisation capabilities are making the primary investigation of colonic cancer easier and more acceptable for patients. Imaging investigations looking at primary, metastatic and recurrent disease are shifting to digital data sets, which can be stored, reviewed remotely, potentially fused with other modalities and reconstructed as 3 dimensional (3D) images for the purposes of advanced diagnostic interpretation and computer assisted surgery. They include virtual colonoscopy, trans-rectal ultrasound, magnetic resonance imaging, positron emission tomography and radioimmunoscintigraphy. Once a colorectal carcinoma is diagnosed, the treatment options available are expanding. Colonic stents are being used to relieve large bowel obstruction, either as a palliative measure or to improve the patient’s overall condition before definitive surgery. Transanal endoscopic microsurgery and minimally invasive techniques are being used with similar outcomes and a lower mortality, morbidity and hospital stay than open trans-abdominal surgery. Transanal endoscopic microsurgery allows precise excision of both benign and early malignant lesions in the mid and upper rectum. Survival of patients with inoperable hepatic metastases following radiofrequency ablation is encouraging. Robotics and telemedicine are taking surgery well into the 21^st century. Artificial neural networks are being developed to enable us to predict the outcome for individual patients. New technology has a major impact on the way we practice surgery for colorectal cancer.

Radio-frequency ablation of liver tumors: assessment of therapeutic response and complications

An alternative to surgical resection of liver tumors, radio-frequency ablation induces in situ thermal coagulation necrosis through the delivery of high-frequency alternating current to the tissues. Imaging helps to detect treatable lesions, guide the placement of the probe, and assess the effect of therapy. Computed tomography (CT) is used most frequently to determine whether the ablation is complete and to screen for early recurrences that may benefit from reablation. Complete ablation creates an area of necrosis that, at CT, is of low attenuation compared with the surrounding liver tissue, is often homogeneous, and has smooth margins. The most important features are the size of the necrotic defect, which, immediately after treatment, should be larger than that of the pretreatment tumor, and the sharpness of the margins, which indicates an abrupt change in attenuation between the necrotic tissue and surrounding liver tissue. Enhancement, when present, is due to perfusion abnormality or granulation tissue and forms a regular rim or a homogeneous zone at the margin of the defect. It is seen immediately after ablation but may be prolonged. Enhancement is affected by the scanning technique. Over time, the size of the defect remains stable or decreases. Any variation from this general pattern is suggestive of incomplete ablation or recurrence.

Isolated hepatic perfusion for unresectable hepatic metastases from colorectal cancer

BACKGROUND

Unresectable colorectal liver metastases are a significant clinical problem. Isolated hepatic perfusion (IHP) is a regional treatment technique that delivers high dose chemotherapy, biologic agents, and hyperthermia via a completely isolated vascular recirculating perfusion circuit as a means of regionally treating liver tumors. This study presents our results of IHP with tumor necrosis factor (TNF) plus melphalan or IHP with melphalan alone followed by infusional floxuridine (FUDR) and leucovorin in patients with advanced or refractory unresectable hepatic colorectal metastases.

METHODS

Fifty-one patients with unresectable colorectal hepatic metastases underwent a 60-minute IHP with 1.5 mg/kg melphalan and hyperthermia (39 degrees C to 40 degrees C). Thirty-two patients received IHP with 1 mg TNF with melphalan and 19 patients had IHP with melphalan alone followed by monthly hepatic intra-arterial infusional (HAI) FUDR (0.2 mg/kg/day) and leucovorin (15 mg/M(2)/day) for 14 days monthly for up to 12 months. Twenty-six patients failed 1 or more previous treatment regimens for established hepatic metastases and 27 had greater than 25% hepatic replacement (PHR) by tumor. Patients were monitored for response, toxicity, and survival.

RESULTS

There was 1 perioperative death (2%), and only 2 patients (4%) had measurable perfusate leak during IHP (both less than 4%). In the 32 patients treated with IHP alone there were no detectable systemic TNF or melphalan levels during perfusion. The overall objective radiographic response rate (all partial [PR]) was 76% (38 of 50 assessable patients) with a median duration of 10.5 months (range, 2 to 21 months). Twenty-four of 31 patients (77%) had a PR after IHP alone and 14 of 19 (74%) after IHP with postperfusion HAI. Median duration of response was 8.5 months after IHP alone and 14.5 months after IHP and HAI; median survival was 16 and 27 months, respectively. There were 18 PRs in 26 patients (69%) whose prior therapy had failed and 18 PRs in 27 patients (67%) with PHR of 25 or greater.

CONCLUSIONS

IHP can be performed with acceptably low morbidity and has significant antitumor activity in patients with unresectable hepatic metastases from colorectal cancer including those with refractory disease or PHR of 25 or greater. HAI appears to prolong the duration of response after IHP, and this combined treatment strategy deserves additional clinical evaluation as a therapeutic modality in this setting.

Focal hepatic ablation using interstitial photon radiation energy

BACKGROUND

Intratumoral ablative therapy is being used increasingly for the treatment of primary and secondary hepatic malignancies. The interstitial point-source photon radiosurgery system (PRS) is a novel ablative technique that uses radiation therapy similar in dosimetry to interstitial brachytherapy.

STUDY DESIGN

To determine the feasibility, toxicity, and local tissue destructive capabilities of the PRS in the liver, preliminary studies in a nontumor-bearing canine model were examined. A 6-month survival study was conducted. Each animal received three radiation treatments, in the right, central, and left hepatic regions. Three low-dose treatments were delivered to each of six animals (group A), generating a 2.0-cm-diameter radiated sphere with a dose of 20 Gy at the lesion edge. Three high-dose treatments were delivered to each of six animals (group B), generating a 3.0-cm-diameter radiated sphere with 20 Gy at the lesion edge.

RESULTS

The treatment reproducibly generated sharply demarcated hepatic ablative lesions proportional to the administered dose. Mean lesion diameter at 1 month was 1.6+/-0.2 cm in group A and 3.4+/-1.0 cm in group B. Lesion size was independent of intrahepatic location, including near vascular structures. PRS therapy, when applied to portal structures, resulted in hilar damage. Hilar damage appeared to be associated with arteriolar thrombosis and bile duct injury. Treatment of regions adjacent to large hepatic veins and the IVC was not associated with vessel thrombosis or stricture.

CONCLUSIONS

PRS ablation is a generally well-tolerated method that results in consistent, well-demarcated, symmetric lesions of complete necrosis with minimal adjacent parenchymal injury. Application of such an approach for the treatment of liver tumors is promising.