Re-Resection for Colorectal Liver Metastasis

Update on optimal treatment for metastatic colorectal cancer from the AGITG expert meeting: ESMO congress 2019

Introduction: Outcomes in metastatic colorectal cancer are improving, due to the tailoring of therapy enabled by better understanding of clinical behavior according to molecular subtype.Areas covered: A review of the literature and recent conference presentations was undertaken on the topic of systemic treatment of metastatic colorectal cancer. This review summarizes expert discussion of the current evidence for therapies in metastatic colorectal cancer (mCRC) based on molecular subgrouping.Expert opinion: EGFR-targeted and VEGF-targeted antibodies are now routinely incorporated into treatment strategies for mCRC. EGFR-targeted antibodies are restricted to patients with extended RAS wild-type profiles, with evidence that they should be further restricted to patients with left-sided tumors. Clinically distinct treatment pathways based on tumor RAS, BRAF, HER2 and MMR status, are now clinically applicable. Evidence suggests therapy for additional subgroups will soon be defined; the most advanced being for patients with KRAS G12 C mutation and gene TRK fusion defects.

[Preconditioning of the liver]

Posthepatectomy liver failure (PHLF) still represents a severe complication after major liver resection associated with a high mortality. In addition to an insufficient residual liver volume various factors play an important role in the pathophysiology of PHLF. These include the quality of the parenchyma, liver function, perfusion, i.e. maintenance of adequate inflow and outflow, as well as the condition of the patient and comorbidities. While the liver volume is relatively easy to evaluate using modern imaging techniques, the evaluation of liver function and liver quality require a differentiated approach. Both factors can be influenced by the constitutional status of the patient, medical history and previous treatment and must be given sufficient consideration in the risk evaluation. An adequate perfusion, e.g. portal and arterial circulation and adequate outflow by at least one hepatic vein as well an adequate biliary drainage should be always guaranteed in order to allow regeneration of the residual liver tissue. Only the understanding of all these aspects will support the surgeon in a correct and safe evaluation of the resectability. Additionally, the liver surgeon should be aware of all available perioperative and postoperative options to treat and to prevent PHLF. In this review article the most important questions regarding the risk factors related to PHLF are presented and the potential therapeutic and prophylactic management is described. The main goal is to ensure functional operability of the patient if oncological resectability is possible. In other words: in the case of correct oncological indication, the liver surgeon should be able to resect what is resectable or, alternatively, make resectable what primarily was not resectable.

Targeted therapy for metastatic colorectal cancer

INTRODUCTION

Outcomes in metastatic colorectal cancer are improving, with better understanding and use of targeted therapies. Areas covered: A review of the literature and recent conference presentations was undertaken on the topic of systemic treatment of metastatic colorectal cancer. This article reviews the current evidence for targeted therapies in advanced colorectal cancer, including up-to-date data regarding anti-epidermal growth factor receptor (EGFR) and anti-vascular endothelial growth factor (VEGF) agents, the relevance of primary tumor location and novel subgroups such as BRAF mutated, HER2 amplified, and mismatch-repair-deficient cancers. Expert commentary: EGFR-targeted and VEGF-targeted antibodies are now routinely incorporated into treatment strategies for metastatic colorectal cancer (mCRC). The use of EGFR-targeted antibodies should be restricted to patients with extended RAS wild-type profiles, and there is evidence that they should be further restricted to patients with left-sided tumors. Clinically, mCRC can be divided into subgroups based on RAS, BRAF, HER2, and MMR status, each of which have distinct treatment pathways.

Update on optimal treatment for metastatic colorectal cancer from the ACTG/AGITG expert meeting: ECCO 2015

The treatment of metastatic CRC (mCRC) has evolved over the last 20 years, from fluoropyrimidines alone to combination chemotherapy and new biologic agents. Median overall survival is now over 24 months for RAS mutated (MT) patients and over 30 months for RAS wild-type (WT) patients. However, there are subgroups of patients with BRAF V600E MT CRC who have a significantly poorer outlook. Newer treatment options are also being explored in select subgroups of patients (anti-HER 2 in HER2 positive mCRC and immunotherapy in patients with defective mismatch repair (dMMR)). The best use of these systemic treatment options, as well as surgery in well-selected patients requires careful consideration of predictive biomarkers and importantly, the optimal sequence in which therapies should be given to derive maximal benefit. A group of colorectal subspecialty medical oncologists from Australia, USA, The Netherlands and Germany met during ECCO 2015 in Vienna to review current practice.

Effectiveness of surgery in liver metastasis from colorectal cancer: experience and results of a continuous improvement process

PURPOSE

The aim of this study was to estimate the effectiveness of surgery in liver metastasis from colorectal cancer.

METHODS

We conducted a prospective and observational study of patients with colorectal liver metastasis operated on at the San Cecilio University Hospital of Granada from March 2003 until June 2013. The primary variables of the result were survival and morbidity before 30 days of the post-operative period. We also measured preoperative and surgical variables.

RESULTS

A total of 147 patients with liver metastasis of colorectal origin underwent surgical removal during the period of study, 38 of whom had repeat surgery. 34 had a second resection, 3 had a third one and one only patient had a fourth one, for a total of 185 registered operations. The global 5-year survival rate was 38 and 17 % after 10 years. There were 115 patients who had neither radiofrequency nor exploratory laparotomy, 38 % of them survived over 60 months. The average disease-free time was 23.6 months ± 47.3, with significant differences observed between types of procedures. Patients that were operated on just once (n = 25) had a five-year actuarial survival rate of 35 %, a morbidity rate of 24 % and a mortality rate of 0.6 % (1 patient only). The average hospital stay was 13.8 days and the disease-free time was 15.8 months.

CONCLUSION

The results obtained in our surgical unit in terms of morbidity, mortality and five-year actuarial survival rates are comparable to those of other units at large institutions, which are currently considered the standards of quality.

Current opinion on optimal systemic treatment for metastatic colorectal cancer: outcome of the ACTG/AGITG expert meeting ECCO 2013

The treatment of metastatic colorectal cancer has evolved greatly in the last 15 years, involving combined chemotherapy protocols and, in more recent times, new biologic agents. Clinical benefit from the use of targeted therapy with bevacizumab, aflibercept, cetuximab, panitumumab and regorafenib in the treatment of metastatic colorectal cancer is now well established with median overall survival accepted as over 24 months, and with super selection for extended RAS patients higher again. The optimal timing of treatment options requires careful consideration of predictive biomarkers, and importantly the potential for interactions, to derive the maximal benefit. A group of colorectal subspecialty medical oncologists from Australia, the USA, the Netherlands and Germany met during ECCO 2013 to discuss current practice. Subsequent new data from the American Society of Clinical Oncology were also reviewed. This article reviews the evidence discussed in support of modern treatments for colorectal cancer and the decision-making behind the treatment choices, with their benefits and risks.

Recurrence location after resection of colorectal liver metastases influences prognosis

AIM

To assess the impact of first recurrence location on survival following surgery of colorectal liver metastases.

METHODS

A total of 265 consecutive patients with colorectal liver metastases undergoing liver surgery (2000-2011) were categorized according to first site of tumor recurrence. Time to recurrence (TTR) and overall survival (OS) were determined. Uni- and multivariate analysis were performed to identify factors associated with TTR and OS.

RESULTS

Median TTR was 1.16 years following liver resection, and 0.56 years following radiofrequency ablation (RFA). Intrahepatic recurrence following liver resection resulted in a significantly shorter median TTR compared to extrahepatic recurrence. Intrapulmonary recurrence was associated with superior survival compared to other recurrence locations. Such patterns were not observed in the RFA-treated group. Multivariate analysis identified the type of surgical treatment and extra-hepatic first-site recurrence (other than lung) as independent predictors for OS. Pre-operative chemotherapy and simultaneous intrahepatic and extrahepatic recurrence were independent predictors for both TTR and OS.

CONCLUSIONS

Patients with intrahepatic recurrence following liver resection have a significantly shorter TTR and OS when compared to patients developing extrahepatic recurrence. Pulmonary recurrence following resection is associated with longer survival. Simultaneous intra- and extrahepatic recurrence is an independent prognostic factor for TTR and OS.

Current opinion on optimal treatment for colorectal cancer

The medical treatment of colorectal cancer (CRC) has evolved greatly in the last 10 years, involving complex combined chemotherapy protocols and, in more recent times, new biologic agents. Advances in adjuvant therapy have been limited to the addition of oxaliplatin and the substitution of oral fluoropyrimidine (e.g., capecitabine) for intravenous 5-fluorouracil with no evidence for improved outcome with biological agents. Clinical benefit from the use of the targeted monoclonal antibodies, bevacizumab, cetuximab and panitumumab, in the treatment of metastatic CRC is now well established, but the optimal timing of their use requires careful consideration to derive the maximal benefit. Evidence to date suggests potentially distinct roles for bevacizumab and EGF receptor-targeted biological agents (cetuximab and panitumumab) in the treatment of metastatic CRC. This article reviews the evidence in support of modern treatments for CRC and the decision-making behind the treatment choices, their benefits and toxicities.

Repeat hepatectomy for recurrent colorectal metastases

BACKGROUND

The oncological benefit of repeat hepatectomy for patients with recurrent colorectal metastases is not yet proven. This study assessed the value of repeat hepatectomy for these patients within current multidisciplinary treatment.

METHODS

Consecutive patients treated by repeat hepatectomy for colorectal metastases between January 1990 and January 2010 were included. Patients undergoing two-stage hepatectomy were excluded. Postoperative outcome was analysed and compared with that of patients who had only a single hepatectomy.

RESULTS

A total of 1036 patients underwent 1454 hepatectomies for colorectal metastases. Of these, 288 patients had 362 repeat hepatectomies for recurrent metastases. Some 225 patients (78·1 per cent) had two hepatectomies, 52 (18·1 per cent) had three hepatectomies, and 11 patients (3·8 per cent) had a fourth hepatectomy. Postoperative morbidity following repeat hepatectomy was similar to that after initial liver resection (27·1 per cent after first, 34·4 per cent after second and 33·3 per cent after third hepatectomy) (P = 0·069). The postoperative mortality rate was 3·1 per cent after repeat hepatectomy versus 1·6 per cent after first hepatectomy. Three- and 5-year overall survival rates following first hepatectomy in patients who underwent repeat hepatectomy were 76 and 54 per cent respectively, compared with 58 and 45 per cent in patients who had only one hepatectomy (P = 0·003). In multivariable analysis, repeat hepatectomy performed between 2000 and 2010 was the sole independent factor associated with longer overall survival.

CONCLUSION

Repeat hepatectomy for recurrent colorectal metastases offers long-term survival in selected patients.

Management of the hepatic lymph nodes during resection of liver metastases from colorectal cancer: a systematic review

BACKGROUND

Hepatic lymph node involvement is generally considered a contraindication for liver resection performed for colorectal liver metastases. However, some advocate hepatic lymphadenectomy in the presence of macroscopic involvement and others routine lymphadenectomy. The aim of this review is to assess the role of lymphadenectomy in resection of liver metastases from colorectal cancer.

METHODS

Medline, Embase and Central databases were searched using a formal search strategy. Trials with survival data with a minimum follow-up of 1 year were considered for inclusion. Meta-analysis was performed using Revman.

RESULTS

A total of 4230 references were identified. Ten reports of nine studies including 926 patients qualified for the review. The prevalence of nodal metastases after routine lymphadenectomy was 16.3%. The overall 3-year and 5-year survival rates in node-positive patients were 9/151 (11.3%) and 2/137 (1.5%), respectively, compared to 3-year and 5-year survival rates of 424/787 (53.9%) and 246/767 (32.1%) in node-negative patients. The odds ratios for 3-year and 5-year survivals in node positive disease compared to node-negative disease were 0.12 (95% CI 0.06 to 0.24) and 0.08 (95% CI 0.03 to 0.22). There was no randomized controlled trial which assessed the survival benefit of routine or "selective" lymphadenectomy.

CONCLUSION

Currently, there is no evidence of survival benefit for routine or selective lymphadenectomy. Survival rates are low in patients with positive lymph nodes draining the liver irrespective of whether they are detected by routine lymphadenectomy or by macroscopic involvement. Further trials in this patient group are required.

[Surgical treatment of liver metastasis in colorectal cancer with simultaneous liver resection]

Metastatic liver disease is a challenging and life-threatening situation often with dismal prognosis. Nearly half of the patients with colorectal cancer develop liver metastasis during the course of their diseases. Hepatic resection is the treatment of choice in patients with colorectal liver metastasis. This study was conducted to compare the results of patients undergoing simultaneous liver and colorectal resection for synchronous liver metastasis and of those for whom a colorectal and liver resection was made separately. A retrospective analysis was performed on 1597 patients who underwent surgery because of colorectal cancer between January 1999 and December 2008. The results of the treatment were separately evaluated in case of the 152 patients who had liver metastasis. The proportion of the liver metastasis was 9.52%. The metastases arose in 40.8% from the rectum and in 31.8% from the sigmoid colon. It proved to be inoperable in 109 (71.7%) of the 152 patients who had liver metastasis. Simultaneous liver resection was performed because of synchronous metastasis in 14 (32.6%) cases (Group 1) and two step resection in 29 (67.4%) cases (Group 2). In case of synchronous operations only minor liver surgery was done. The mean size of the metastasis was 2.6 cm in diameter in Group 1 and 4.6 cm in Group 2 (p<0.005). The transfused blood volume was 0.3 U/patient. Only minor complications could be observed in Group 1. The hospitalization was 13.1 days in Group 1 and 11.7 days in Group 2. The mean survival time was 37.3 and 47.9 months (p<0.005). Simultaneous liver resection seems to be a safe procedure on those patients who develop small metastases with a limited number. However, the optimal timing of the liver resection and the identification of patients who will have the greatest benefit in survival still remain obscure.

Current management of colorectal hepatic metastasis

In the USA, cancers of the colon and rectum are the third most common site of new cancer cases and cancer deaths. With improved screening and adjuvant therapy, the survival of patients has increased substantially over the last decade. However, patients with metastatic disease often have limited survival. Hepatic metastasis is one of the most frequent sites of metastatic disease. In fact, 35-55% of patients with colorectal cancer will develop hepatic metastasis at some time during the course of their disease. Patients who are able to undergo complete resection of their hepatic metastases have the best chance of long-term survival. The goal of hepatic resection is to achieve complete resection of all metastases with microscopically negative surgical margins while preserving sufficient hepatic parenchyma. Survival following hepatic resection of colorectal metastasis now approaches 35-50%. However, approximately 65% of patients will have a recurrence at 5 years. Increasingly chemotherapeutic agents are being offered in the preoperative setting prior to operation. At the time of operation, patients with extensive hepatic disease can sometimes be offered ablative therapies combined with resection or staged approaches. Modern management of hepatic colorectal metastases necessitates a multidisciplinary approach to effectively treat these patients and increase the number of patients who will benefit from resection.

Resection of colorectal liver metastases: is a resection margin of 3 mm enough? : a multicenter analysis of the GAST Study Group

BACKGROUND

A safety margin of > or =10 mm is generally accepted in surgery for colorectal metastases. It is reasonable that modern methods of liver parenchyma dissection may allow for a reduction in this distance.

METHODS

A total of 333 patients were included in a multicenter trial after resection of colorectal liver metastases. Dissection of the liver had been performed with a CUSA, UltraCision, or water-jet dissector. The size of the resection margin was correlated with recurrence risk and survival.

RESULTS

The median hepatic recurrence-free survival reached 35 months for all patients; median recurrence-free survival was 24 months and overall survival was 41 months. Univariate analysis of different groups denoting the extent of resection margin (> or =10 mm, 6-9 mm, 3-5 mm, 1-2 mm, 0 mm (R1)) indicated that a margin of 1-2 mm leads to a significantly reduced median hepatic recurrence-free survival of 20 months (p = 0.004) and recurrence-free survival of 19 months (p = 0.011). Patients with R1 resection had the worst prognosis. Overall survival was not influenced by the size of the resection margin. Surgical margins were significantly reduced in simultaneous resections of four or more liver metastases and in cases in which metastatic infiltration of central liver segments was present. At multivariate analysis, resection margins of 1-2 mm and 0 mm were independent predictors of hepatic recurrence and overall recurrence.

CONCLUSION

The indication for resection of metastases can be safely extended to cases in which tumors sit closer than 1 cm to nonresectable structures.

Meta-analysis of clinical outcome after first and second liver resection for colorectal metastases

BACKGROUND

The perioperative risk and long-term survival benefit of repeat hepatectomy for patients with liver metastases from colorectal cancer, compared with that of a first liver resection, has been reported with varying results in the literature.

METHODS

The literature was searched using Medline, Embase, Ovid, and Cochrane databases for all studies published from 1992 to 2006. Two authors independently extracted data using the following outcomes: postoperative complications and mortality; disease recurrence; and long-term survival. Trials were assessed using the modified Newcastle-Ottawa Score. Random-effect meta-analytical techniques were used for analysis.

RESULTS

Twenty-one studies met the inclusion criteria, comprising 3,741 patients. The use of adjuvant chemotherapy was similar in both groups (odds ratio [OR] = 0.97; 95% confidence interval [CI] = 0.54, 1.74; P = .92), as was the number of hepatic nodules present at the time of first or second resection (weighted mean difference [WMD] = 0.18; 95% CI = -0.22, 0.57; P = .380). Wedge resection was carried out less often at first hepatectomy (39% vs 46%; OR = 0.66; 95% CI = 0.44, 1.00; P = .05). There was significantly less blood loss in patients undergoing first versus second hepatectomy (WMD = 238 ml; 95% CI = 90, 385; P = .002). There was no difference in perioperative morbidity (OR = 1.01; 95% CI = 0.65, 1.55; P = .98), mortality (OR = 1.01; 95% CI = 0.18, 5.72; P = .99) or long-term survival (HR = 0.90; 95% CI = .66, 1.24; P = .530) between groups.

CONCLUSIONS

Repeat hepatectomy for patients with colorectal cancer metastases is safe and provides survival benefit equal to that of a first liver resection.

Management of intrahepatic recurrence after curative treatment of colorectal liver metastases

BACKGROUND

Management of intrahepatic recurrence after complete surgical treatment for colorectal liver metastases is not well defined. The aim of this study was to analyse the survival results of patients who had repeat liver resection for intrahepatic recurrence and to evaluate prognostic indicators for survival.

METHODS

Between 1991 and 2005, 55 patients had repeat liver resection for isolated intrahepatic recurrence. The long-term survival results were assessed. Univariable and multivariable analyses were used to identify prognostic indicators for survival after repeat hepatectomy.

RESULTS

The median survival was 53 (range 2-97) months and the 5-year survival rate was 49 per cent. In univariable analysis, size of largest initial liver metastasis, margin of initial liver surgery, carcinoembryonic antigen (CEA) level before and after initial liver surgery, liver disease-free survival, margin of repeat liver surgery, operation type of repeat surgery and CEA level before and after repeat surgery were significant prognostic factors. In multivariable analysis, largest initial liver metastasis 4 cm or less and CEA level 5 ng/ml or less after repeat liver surgery were independently associated with improved survival.

CONCLUSION

Repeat hepatectomy can achieve an acceptable survival in selected patients with isolated intrahepatic recurrence.

Prolonged survival of mice with multiple liver metastases of human colon cancer by intravenous administration of replicable E1B-55K-deleted adenovirus with E1A expressed by CEA promoter

Liver is the most preferential site for metastasis of colon cancer. We, in the present study, constructed a self-replicable adenovirus in which E1A is driven by a CEA promoter and E1B-55K is deleted from the E1B region (AdCEAp/Rep) and examined its effects on multiple metastases of a human colon cancer cell in a mouse xenograft model. We first showed effective replication of the virus in various CEA-producing human colon cancer cells (M7609, HT-29) and subsequent lysis of the infected cells in vitro. We then demonstrated that a single intratumoral injection of the virus (1 x 10(8) PFU/100 microl) induced a complete regression of subcutaneous tumors (M7609) inoculated into nude mice. Further, we demonstrated that systemic administration of the virus (1 x 10(8) PFU/100 microl) through the tail vein to nude mice, which 1 week prior had been inoculated with tumor cells (colon carcinoma cell line HT-29) via the spleen and showed apparent multiple metastases in the liver, effectively suppressed the metastasis formation. The mean survival time of the treated mice was significantly longer than that of the controls. Thus, the systemic administration of AdCEAp/Rep was considered to be effective on multiple liver metastases of CEA-positive colon cancer in a xenograft model.

Modelo de indução de necrose focal hepática: estudo experimental em ratos

OBJETIVO: Investigar a área de necrose focal induzida pela injeção intra-hepática de quatro diferentes substâncias no fígado de ratos. MÉTODOS: Foram utilizados 25 ratos Wistar, com peso variando entre 200 a 250 g, distribuidos em 5 grupos, que receberam 0,1cc das seguintes substâncias: Grupo I (Gr. I) - soro fisiológico a 0,9% (controle). Grupo II (Gr. II) - glicose hipertônica a 50%. Grupo III (Gr. III) - NaCl a 20%. Grupo IV (Gr. IV) - formol a 10%. Grupo V (Gr. V) - etanol. Os animais foram submetidos a laparotomia para que a punção fosse realizada no lobo hepático médio sob visão direta. Todos os animais foram sacrificados após 24 horas da injeção.. Os fígados foram avaliados histologicamente, com o intuito de mensurar a área do tecido necrótico. RESULTADOS: Nos cinco grupos estudados observou-se: Gr. I - 2829mm² (controle); Gr. II - 3805mm² (glicose hipertônica); Gr. III - 3930mm² (NaCl); Gr. IV - 4532mm² (formol) e Gr. V - 6432mm² (etanol). A análise estatística destes valores foi feita pelo método das comparações múltiplas. CONCLUSÃO: 1. O soro fisiológico foi à substância que causou a menor área de necrose (P< 0,05). 2. O NaCl a 20% e a glicose hipertônica a 50% produzem efeitos semelhantes (P > 0,05). 3. O formol a 10% produziu necrose mais extensa que a glicose hipertônica a 50% (P < 0,05) e que o NaCl a 20%, porém não apresentou diferença estatisticamente significativa com esta última (P > 0,05). 4. O etanol foi à substância que, comparada com as outras, mais necrose produziu (P < 0,05).

Interstitial laser hyperthermia and the biological characteristics of tumor: study in a murine model of colorectal liver metastases

BACKGROUND DATA

Percutaneously applied interstitial laser hyperthermia (ILH) is a minimally invasive therapy that is currently used in the treatment of liver metastases. Despite its documented efficacy, theoretical considerations and evidence based on animal studies suggest the potential for stimulating tumor growth, especially following surgery. This study investigates the influence of ILH on tumor behaviour in an animal model of colorectal liver metastases.

MATERIALS AND METHODS

A model of colorectal cancer liver metastases in male inbred CBA mice was used. Laser hyperthermia was applied to tumor tissue using a bare optical quartz from a Medilas fibertom 4100 Nd:YAG surgical laser generator. Liver injury by ILH was initially produced in three experimental groups of animals at different time points in the development of metastases. ILH was applied (i) to normal liver 10 days prior to tumor induction, (ii) immediately prior to tumor induction, and (iii) 15 days after tumor induction to achieve approximately 8% liver destruction. Animals were killed 21 days after tumor induction, and the effects of ILH on overall tumor development were compared with controls using stereological assessment of tumor volume and by histology. In a separate experimental group, the effects of ILH on fully established tumors were examined. Suitable tumors were selected 21 days after induction and partially destroyed by ILH at a standard energy setting. Animals were then killed 15 days later, and the growth rate of the residual viable tumors was compared to control tumors having undergone sham procedures.

RESULTS

No significant stimulation of tumor growth was evident in any of the experimental groups following ILH, irrespective of the time of application. Incomplete tumor destruction also had no influence on subsequent tumor growth.

CONCLUSION

ILH does not influence the biological characteristics of tumors during any stage of the metastatic process.

Repeat hepatectomy for colorectal liver metastases: A worthwhile operation?

BACKGROUND AND OBJECTIVES

After curative resection of hepatic colorectal metastases, 10-20% of patients experience a resectable hepatic recurrence. We wanted to assess the expected risk-to-benefit ratio in comparison to first hepatectomy and to determine the prognostic factors associated with survival.

METHODS

Twenty-nine patients from a group of 152 patients resected for colorectal liver metastases underwent 32 repeat hepatectomies.

RESULTS

In-hospital mortality was 3.5% (1/29 patients); the morbidity after repeat hepatectomy was lower than that after first hepatic resection. Combined extrahepatic surgery was performed on 34.5% of repeat hepatectomies vs. 6.9% of first hepatectomies (P = 0.01). Overall actuarial 3-year survival was 35.1%: four patients have survived more than 3 years and one survived for more than 5 years. The number of hepatic metastases and the carcinoembryonic antigen (CEA) serum levels were significant prognostic factors on univariate analysis. The synchronous resection of hepatic and extrahepatic disease was not associated with a lower survival rate when compared with that of patients without extrahepatic localization: three patients of the former group are alive and disease-free at more than 2 years.

CONCLUSIONS

Repeat hepatic resection can provide long-term survival rates similar to those of first liver resection, with comparable mortality and morbidity. The presence of resectable extrahepatic disease must not be an absolute contraindication to synchronous hepatectomy because long-term survival is possible.

Interstitial laser thermotherapy in the treatment of colorectal liver metastases

Metastatic liver disease is the commonest cause of death in patients with colorectal cancer. A small proportion of these patients (10%) may be treated by surgical resection with five year survival approaching 35-40%. Alternative treatment modalities for localised hepatic disease include in situ ablative techniques that have the advantages of percutaneous application and minimal morbidity. These include Interstitial Laser Thermotherapy (ILT), Radio Frequency Ablation, Percutaneous Microwave therapy, and Focussed Ultrasound Therapy. This article focuses specifically on the development and utilisation of ILT in the treatment of colorectal liver metastases. It provides a review of the pathophysiological factors involved, present status of clinical studies, and future directions. ILT is a safe technique for the treatment of colorectal liver metastases. It may be delivered by minimally invasive techniques to lesions considered unresectable by present criteria. Limitations include the extent and completeness of tumour necrosis achieved as well as imaging techniques. Clinical problems include a lack of controlled studies. Assessment of long-term survival in prospective randomised trials is needed to assess the efficacy of this procedure.

Current treatment for colorectal cancer metastatic to the liver

Surgery is currently the only available treatment option which offers the potential for cure for patients with liver metastases from colorectal cancer. Of those who undergo a potentially curative operation for their primary tumour but subsequently recur, almost 80% will develop evidence of metastatic disease within the liver. Greater experience and improvements in technique in liver surgery, with an increasingly aggressive surgical approach to metastatic colorectal cancer to the liver, has resulted in prolonged disease-free survival with 5-year rates varying from 21% to 48%. In order to increase these numbers further and to treat patients not eligible for surgical therapy, new treatment modalities and strategies have been developed. This review presents an update of the current treatment for colorectal disease metastatic to the liver.

Regional versus systemic delivery of recombinant vaccinia virus as suicide gene therapy for murine liver metastases

OBJECTIVE

Specific and efficient tumor-targeted gene delivery is the major goal for successful cancer gene therapy.

SUMMARY BACKGROUND DATA

A recombinant thymidine kinase-deleted vaccinia virus (vv) encoding the firefly luciferase (luc) reporter gene or the prodrug converter gene cytosine deaminase (CD) was constructed. The authors compared the extent, duration, and pattern of transgene (luc) expression in vivo after portal venous, intraperitoneal, or intravenous virus administration and survival after treatment with the vv containing CD followed by the prodrug 5-fluorocytosine (5-FC) in a murine model of disseminated liver metastases from colon cancer.

METHODS

Recombinant vv containing the luc transgene within the thymidine kinase locus was administered to mice with isolated liver metastases from an MC38 adenocarcinoma. Transgene expression was determined in tumor and organs at various time points. Tumor-bearing mice were treated with recombinant vv containing CD and 5-FC or with appropriate controls and followed for survival.

RESULTS

Tumor-specific gene delivery was achieved irrespective of administration route, with gene expression in tumors increased by up to 100,000-fold compared with normal tissues. There was significantly increased transgene expression in tumor after portal venous or intraperitoneal virus administration (p = 0.001 vs. systemic). Treatment using a CD-expressing vv and systemic 5-FC resulted in a significant survival benefit in all treatment groups compared with controls (p < 0.007); there was no additional benefit for portal venous or intraperitoneal virus administration.

CONCLUSIONS

Suicide gene therapy using vv with the CD/5-FC system leads to tumor-specific gene expression and improved survival and can result in cure of established liver metastases.

Management of hepatic metastases

Although the liver is the most common site of metastatic disease from a variety of tumor types, isolated hepatic metastases most commonly occur from colorectal cancer and, less frequently, from neuroendocrine tumors, gastrointestinal sarcoma, ocular melanoma, and others. Complete evaluation of the extent of metastatic disease, both intrahepatically and extrahepatically, is important before considering treatment options. Based on a preponderance of uncontrolled studies for hepatic metastatic colorectal carcinoma, surgical resection offers the only potential for cure of selected patients with completely resected disease, with 5-year survival rates of 25% to 46%. Systemic and hepatic arterial infusion chemotherapy may be useful treatment options in patients with unresectable disease and possibly as an adjuvant treatment after liver resection. Other techniques of local tumor ablation, including cryotherapy and radiofrequency ablation, although promising, remain unproved. Management of hepatic metastases from neuroendocrine tumors and other noncolorectal primary tumors should be individualized based on the patient's clinical course, extent of disease, and symptoms.

Repeat hepatectomy for colorectal liver metastases

OBJECTIVE

The authors assess the long-term results of repeat hepatectomies for recurrent metastases of colorectal cancer and determine the factors that can predict survival.

SUMMARY BACKGROUND DATA

Safer techniques of hepatic resection have allowed surgeons to consider repeat hepatectomy for colorectal metastases in an increasing number of patients. However, higher operative bleeding and increased morbidity have been reported after repeat hepatectomies, and the long-term benefit of these procedures needs to be evaluated.

STUDY POPULATION

Sixty-four patients from a group of 243 patients resected for colorectal liver metastases were submitted to 83 repeat hepatectomies (64 second, 15 third, and 4 fourth hepatectomies). Combined extrahepatic surgery was performed in 21 (25%) of these 83 repeat hepatectomies.

RESULTS

There was no intraoperative or postoperative mortality. Operative bleeding was not significantly increased in repeat hepatectomies as compared to first resections. Morbidity and duration of hospital stay were comparable to first hepatectomies. Overall and disease-free survival after a second hepatectomy were 60% and 42%, respectively, at 3 years and 41% and 26%, respectively, at 5 years. Factors of prognostic value on univariate analysis included the curative nature of first and second hepatectomies (p = 0.04 and p = 0.002, respectively), an interval between the two procedures of more than 1 year (p = 0.003), the number of recurrent tumors (p = 0.002), serum carcinoembryonic antigen levels (p = 0.03), and the presence of extrahepatic disease (p = 0.03). Only the curative nature of the second hepatectomy and an interval of more than 1 year between the two procedures were independently related to survival on multivariate analysis.

CONCLUSIONS

Repeat hepatectomies can provide long-term survival rates similar to those of first hepatectomies, with no mortality and comparable morbidity. Combined extrahepatic surgery can be required to achieve tumor eradication. Repeat hepatectomies appear worthwhile when potentially curative.