Prospective phase II trial of combination hepatic artery infusion and systemic chemotherapy for unresectable colorectal liver metastases: Long term results and curative potential

Review of Intra-Arterial Therapies for Colorectal Cancer Liver Metastasis

Simple Summary

Colorectal cancer liver metastasis occurs in more than 50% of patients with colorectal cancer and is thought to be the most common cause of death from this cancer. The mainstay of treatment for inoperable liver metastasis has been combination systemic chemotherapy with or without the addition of biological targeted therapy with a goal for disease downstaging, for potential curative resection, or more frequently, for disease control. For patients with dominant liver metastatic disease or limited extrahepatic disease, liver-directed intra-arterial therapies including hepatic arterial chemotherapy infusion, chemoembolization and radioembolization are alternative treatment strategies that have shown promising results, most commonly in the salvage setting in patients with chemo-refractory disease. In recent years, their role in the first-line setting in conjunction with concurrent systemic chemotherapy has also been explored. This review aims to provide an update on the current evidence regarding liver-directed intra-arterial treatment strategies and to discuss potential trends for the future.

Abstract

The liver is frequently the most common site of metastasis in patients with colorectal cancer, occurring in more than 50% of patients. While surgical resection remains the only potential curative option, it is only eligible in 15–20% of patients at presentation. In the past two decades, major advances in modern chemotherapy and personalized biological agents have improved overall survival in patients with unresectable liver metastasis. For patients with dominant liver metastatic disease or limited extrahepatic disease, liver-directed intra-arterial therapies such as hepatic arterial chemotherapy infusion, chemoembolization and radioembolization are treatment strategies which are increasingly being considered to improve local tumor response and to reduce systemic side effects. Currently, these therapies are mostly used in the salvage setting in patients with chemo-refractory disease. However, their use in the first-line setting in conjunction with systemic chemotherapy as well as to a lesser degree, in a neoadjuvant setting, for downstaging to resection have also been investigated. Furthermore, some clinicians have considered these therapies as a temporizing tool for local disease control in patients undergoing a chemotherapy ‘holiday’ or acting as a bridge in patients between different lines of systemic treatment. This review aims to provide an update on the current evidence regarding liver-directed intra-arterial treatment strategies and to discuss potential trends for the future.

Locoregional Therapies for Colorectal Cancer Liver Metastases: Options Beyond Resection

Colorectal cancer was the third most common malignancy worldwide in 2018, and most patients present with or develop distant metastases. Colorectal liver metastases are most commonly observed because of the vascular drainage of the colon and superior rectum. Current guidelines recommend surgical resection as first-line treatment; however, 80% to 90% of patients with colorectal liver metastases are ineligible for primary resection. For patients with unresectable disease, a multidisciplinary treatment approach is favored, incorporating systemic therapy and a toolbox of local ablative therapies. These treatments either aim at cytoreduction to enable a conversion to surgical resectability or control of disease progression and spread. Each of these treatments carries unique outcomes and risk profiles, thereby contributing to an individualized treatment strategy for patients with colorectal liver metastases. This review summarizes evidence on hepatic artery infusion, stereotactic body radiation therapy, thermal ablation, transarterial chemoembolization with drug-eluding beads, and transarterial radioembolization for treatment of colorectal liver metastases. Results of large-scale prospective and retrospective studies and international guidelines are discussed to provide detailed background on the current and prospective use of local ablative techniques in management of colorectal liver metastases.

Intraarterial Chemotherapy for Liver Metastases

Colorectal cancer (CRC) is one of the leading cancers globally in terms of both incidence and cancer-related mortality. Liver metastatic disease is the main prognostic driver for patients with CRC. The management options for liver metastatic CRC continue to evolve, particularly with the incorporation of locoregional therapies into the treatment paradigm. Hepatic arterial infusion (HAI) chemotherapy is one such liver directed approach used with the goal of converting patients to liver resection, reducing the risk of recurrence, treating recurrent disease, and most importantly improving overall survival. This article summarizes the role of HAI chemotherapy in the treatment of liver metastatic CRC.

Surgical Management of Colorectal Cancer Liver Metastases

Approximately 50% of colorectal cancer patients develop liver metastases. Hepatic metastases represent the most common cause of colorectal cancer-related mortality. Metastasectomy, if possible, represents the most effective treatment strategy; 20% of patients will be cured and more than 50% survive at least 5 years. Nuances to treatment planning hinge on whether patients present with resectable disease upfront, whether the future liver remnant is adequate, and whether the primary tumor, if present, is colon versus rectal in origin. This article discusses considerations impacting our approach to patients with colorectal liver metastases and the role for various multimodal treatment options.

Factors Associated With Local Tumor Control and Complications After Thermal Ablation of Colorectal Cancer Liver Metastases: A 15-year Retrospective Cohort Study

INTRODUCTION

The purpose of this study was to identify risk factors associated with local tumor progression-free survival (LTPFS) and complications after colorectal liver metastases (CLM) thermal ablation (TA).

PATIENTS AND METHODS

This retrospective analysis included 286 patients with 415 CLM undergoing TA (radiofrequency and microwave ablation) in 378 procedures from January 2003 to July 2017. Prior hepatic artery infusion (HAI), bevacizumab, pre-existing biliary dilatation, ablation modality, minimal ablation margin (MM), prior hepatectomy, CLM number, and size were analyzed as factors influencing complications and LTPFS. Statistical analysis included the Kaplan-Meier method, Cox proportional hazards model, competing risk analysis, univariate/multivariate logistic/exact logistic regressions, and the Fisher exact test. Complications were reported according to modified Society of Interventional Radiology guidelines.

RESULTS

The median follow-up was 31 months. There was no LTP for MM > 10 mm. Smaller tumor size, increased MM, and prior hepatectomy correlated with longer LTPFS. The major complications occurred following 28 (7%) of 378 procedures. There were no biliary complications in HAI-naive patients, versus 11% in HAI patients (P < .001), of which 7% were major. Biliary complications predictors in HAI patients included biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, ablation with 6 to 10 mm and > 10 mm MM resulted in major biliary complication rates of 4% and 21% (P = .0011), with corresponding LTP rates of 24% and 0% (P = .0033). In HAI-naive patients, the LTP rates for 6 to 10 mm and > 10 mm MM were 27% and 0%, respectively.

CONCLUSIONS

No LTP was seen for MM > 10 mm. Biliary complications occurred only in HAI patients, especially in those with biliary dilatation, bevacizumab, and MM > 10 mm. In HAI patients, MM of 6 to 10 mm resulted in 76% local tumor control and 4% major biliary complications incidence.

Safety and feasibility of initiating a hepatic artery infusion pump chemotherapy program for unresectable colorectal liver metastases: A multicenter, retrospective cohort study

INTRODUCTION

Hepatic artery infusion pump (HAIP) chemotherapy is a specialized therapy for patients with unresectable colorectal liver metastases (uCRLM). Its effectiveness was demonstrated from a high volume center, with uncertainty regarding the feasibility and safety at other centers. Therefore, we sought to assess the safety and feasibility of HAIP for the management of uCRLM at other centers.

METHODS

We conducted a multicenter retrospective cohort study of patients with uCRLM treated with HAIP from January 2003 to December 2017 at six North American centers initiating the HAIP program. Outcomes included the safety and feasibility of HAIP chemotherapy.

RESULTS

We identified 154 patients with HAIP insertion and the median age of 54 (48-61) years. The burden of disease was >10 intra-hepatic metastatic foci in 59 (38.3%) patients. Patients received at least one cycle of systemic chemotherapy before HAIP insertion. Major complications occurred in 7 (4.6%) patients during their hospitalization and 13 (8.4%) patients developed biliary sclerosis during follow-up. A total of 148 patients (96.1%) received at least one-dose of HAIP chemotherapy with a median of 5 (4-7) cycles. 78 patients (56.5%) had a complete or partial response and 12 (7.8%) received a curative liver resection.

CONCLUSION

HAIP programs can be safely and effectively initiated in previously inexperienced centers with good response.

Contemporary Imaging of the Surgically Placed Hepatic Arterial Infusion Chemotherapy Pump

Hepatic arterial infusion (HAI) of chemotherapy is a locoregional treatment strategy for hepatic malignancy involving placement of a surgically implanted pump or percutaneous port-catheter device into a branch of the hepatic artery. HAI has been used for metastatic colorectal cancer for decades but has recently attracted new attention because of its potential impact on survival, when combined with systemic therapy, in patients presenting with unresectable hepatic disease. Although various HAI device-related complications have been described, little attention has been given to their appearance on imaging. Radiologists are uniquely positioned to identify these complications given that patients receiving HAI therapy typically undergo frequent imaging and may have complications that are delayed or clinically unsuspected. Therefore, this article reviews the multimodality imaging considerations of surgically implanted HAI devices. The role of imaging in routine perioperative assessment, including the normal postoperative appearance of the device, is described. The imaging findings of potential complications, including pump pocket complications, catheter or arterial complications, and toxic or ischemic complications, are presented, with a focus on CT. Familiarity with the device and its complications will aid radiologists in playing an important role in the treatment of patients undergoing HAI therapy.

Role of Hepatic Artery Infusion Chemotherapy in Treatment of Initially Unresectable Colorectal Liver Metastases: A Review

Importance

Although liver metastasis develops in more than half of patients with colorectal cancer, only 15% to 20% of these patients have resectable liver metastasis at presentation. Moreover, patients with initially unresectable colorectal liver metastasis (IU-CRLM) who progress on first-line systemic chemotherapy have limited treatment options. Hepatic arterial infusion chemotherapy (HAIC), in combination with systemic chemotherapy, leverages a multimodality approach to achieving control of hepatic disease and/or expanding resectability in patients with liver-only disease or liver-dominant disease.

Observations

Intra-arterial delivery of agents with high first-pass hepatic extraction (eg, floxuridine) limits systemic toxic effects and allows for administration of systemic chemotherapy at near-full doses. Hepatic arterial infusion chemotherapy in conjunction with systemic chemotherapy augments response rates up to 92% in patients who are chemotherapy naive, and up to 85% in pretreated patients with IU-CRLM. In turn, these responses translate into encouraging rates of conversion to resectability (CTR). Prospective trials have reported CTR rates as high as 52% in heavily pretreated patients with IU-CRLM who have an extensive hepatic disease burden. As such, CTR remains a compelling indication for liver-directed chemotherapy in this subset of patients. This review discusses the biological rationale for HAIC, evolution of rational combinations with systemic chemotherapy, contemporary evidence for CTR using HAIC and systemic chemotherapy, juxtaposition with rates of CTR using systemic chemotherapy alone, and morbidity and toxic effect profiles of HAIC.

Conclusions and Relevance

The argument is made for consideration of earlier initiation of HAIC in patients with IU-CRLM who are chemotherapy naive and for adoption of HAIC strategies to augment rates of resectability in patients who have failed first-line systemic chemotherapy before proceeding to second-line or third-line regimens.

Hepatic artery infusion pumps

The preferential blood supply from the hepatic artery to liver tumors allows for the regional delivery of chemotherapy, commonly referred to as hepatic artery infusion chemotherapy via a subcutaneous pump. Hepatic artery infusion chemotherapy has been demonstrated to improve overall survival in select patients with colorectal liver metastasis and is a promising treatment for unresectable intrahepatic cholangiocarcinoma. This review focuses on the technical aspects of hepatic artery infusion pump placement.

Liver transplantation for colorectal liver metastasis

PURPOSE OF REVIEW

The aim of this review is to discuss existing data on liver transplantation for colorectal liver metastasis, emerging controversies, and future directions.

RECENT FINDINGS

Contemporary experience with transplanting patients with liver metastasis from colon cancer is mainly derived from European centers, with a large proportion being from a single institution (SECA study), made possible in part by a relatively high donor pool. The initial results prove to be encouraging by demonstrating an overall survival advantage over unresectable patients with liver-limited disease managed with chemotherapy only. Recurrence patterns, however, suggest a need for better patient selection and treatment sequencing optimization. In North America, the main barriers in establishing similar protocols result from national liver graft shortage, which represents an issue of competing resources when indications have yet to be well defined. Evolving strategies in transplantation, such as the utilization of marginal liver grafts and living donor liver transplantation might constitute potential solutions.

SUMMARY

Evidence suggests a potential survival benefit of liver transplantation for a subset of patients with unresectable liver-limited CRLM. Further prospective trials are needed to clarify the role and feasibility of this treatment strategy in oncotransplantation.

Initial systemic chemotherapeutic and targeted therapy strategies for the treatment of colorectal cancer patients with liver metastases

Introduction: The liver is the most common metastatic site in colorectal cancer with more than half the patients developing a liver metastasis either at the time of their diagnosis (synchronous) or later (metachronous). Surgical resection remains the principal curative approach that offers significant survival improvements. However, upfront surgery is only possible in about 10-20% of patients at the time of diagnosis, making the consideration of other treatment modalities essential. Areas covered: In this review, the authors provide an overview of the standard approaches for the initial management of patients with colorectal cancer with liver metastases. They then provide an up-to-date discussion of first-line systemic chemotherapy/targeted therapy options in the contexts of initially resectable and unresectable disease and review toxicities and complications following these options. Expert opinion: Advances in chemotherapeutic agents and biological targeted therapies have improved the prognosis of colorectal cancer with liver metastases. However, there is still no 'single best approach', making further trials necessary to provide more evidence.

Current status of surgical treatment of colorectal liver metastases

Liver metastasis (LM) is one of the major causes of death in patients with colorectal cancer (CRC). Approximately 60% of CRC patients develop LM during the course of their illness. About 85% of these patients have unresectable disease at the time of presentation. Surgical resection is currently the only curative treatment for patients with colorectal LM (CRLM). In recent years, with the help of modern multimodality therapy including systemic chemotherapy, radiation therapy, and surgery, the outcomes of CRLM treatment have significantly improved. This article summarizes the current status of surgical treatment of CRLM including evaluation of resectability, treatment for resectable LM, conversion therapy and liver transplantation for unresectable cases, liver resection for recurrent CRLM and elderly patients, and surgery for concomitant hepatic and extra-hepatic metastatic disease (EHMD). We believe that with the help of modern multimodality therapy, an aggressive oncosurgical approach should be implemented as it has the possibility of achieving a cure, even when EHMD is present in patients with CRLM.

Regional therapies for the treatment of primary and metastatic hepatic tumors: A disease-based review of techniques and critical appraisal of current evidence

The practice of hepatic surgery has become increasingly complex as additional therapeutic options emerge to treat both primary and metastatic tumors of the liver. Liver-directed therapy options include selective internal radiation therapy (SIRT), stereotactic body radiation therapy, chemoembolization, bland embolization, hepatic artery infusion chemotherapy (HAIC), and ablative techniques such as microwave or radiofrequency ablation. Hepatocellular carcinoma has been treated with many of these therapies for palliation of symptoms, definitive treatment, and as a bridge to transplantation. Intrahepatic cholangiocarcinoma, particularly patients with unresectable disease, have demonstrated clinical responses to both SIRT as well as HAIC. Colorectal liver metastases have been treated with all of these techniques with varying degrees of success depending on the clinical scenario. A detailed understanding of these technologies and the evidence supporting their use is essential for the modern hepatic surgeon to properly sequence therapies and provide salvage options when first-line treatment has failed. This review describes these techniques and their appropriate usage based on the disease of interest and the respective evidence currently available.

The Role of Liver-Directed Therapy in Metastatic Colorectal Cancer

Purpose of Review

Colorectal cancer liver metastasis is a major clinical problem, and surgical resection is the only potentially curative treatment. We seek to discuss various liver-directed therapy modalities and explore their roles in the evolving realm of treatment strategies for metastatic colorectal cancer.

Recent Findings

Clinical outcomes for patients with colorectal cancer liver metastases have improved as more patients undergo potentially curative resection and as the armamentarium of systemic treatment and liver-directed therapies continues to expand. Liver-directed therapies have been developed as adjuncts to improve resectability, employed in the adjuvant setting to potentially reduce local recurrence rates, and utilized in the palliative setting with the aim to improve overall survival.

Summary

Ongoing research is expected to validate the role of these evolving therapeutic options, and determine how best to sequence and when to apply these therapies.

Conformal Radiation Therapy or Stereotactic Body Radiation Therapy: Institutional Experience in the Management of Colorectal Liver Metastases by Radiation Therapy

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