Arterial therapies of colorectal cancer metastases to the liver

Metastatic disease to the liver: Locoregional therapy strategies and outcomes

Secondary cancers of the liver are more than twenty times more common than primary tumors and are incurable in most cases. While surgical resection and systemic chemotherapy are often the first-line therapy for metastatic liver disease, a majority of patients present with bilobar disease not amenable to curative local resection. Furthermore, by the time metastasis to the liver has developed, many tumors demonstrate a degree of resistance to systemic chemotherapy. Fortunately, catheter-directed and percutaneous locoregional approaches have evolved as major treatment modalities for unresectable metastatic disease. These novel techniques can be used for diverse applications ranging from curative intent for small localized tumors, downstaging of large tumors for resection, or locoregional control and palliation of advanced disease. Their use has been associated with increased tumor response, increased disease-free and overall survival, and decreased morbidity and mortality in a broad range of metastatic disease. This review explores recent advances in liver-directed therapies for metastatic liver disease from primary colorectal, neuroendocrine, breast, and lung cancer, as well as uveal melanoma, cholangiocarcinoma, and sarcoma. Therapies discussed include bland transarterial embolization, chemoembolization, radioembolization, and ablative therapies, with a focus on current treatment approaches, outcomes of locoregional therapy, and future directions in each type of metastatic disease.

Is dual-phase C-arm CBCT sufficiently accurate for the diagnosis of colorectal cancer liver metastasis during liver intra-arterial treatment?

PURPOSE

This study aimed to estimate the accuracy of dual-phase C-arm cone beam computed tomography (CBCT) for the detection of colorectal cancer liver metastases, as compared with multidetector computed tomography (MDCT).

MATERIALS AND METHODS

Between March 2014 and December 2016, 49 consecutive patients referred for intra-arterial treatment for colorectal cancer liver metastases were enrolled in a single-center observational study. All patients were examined with MDCT and with dual-phase C-arm cone beam computed tomography performed after iodine injection in the proper hepatic artery before intra-arterial treatment. Two blinded observers independently reviewed all examinations. Diagnostic accuracy was determined using both a six-cell matrix method and a "worst-case scenario."

RESULTS

Readers identified at MDCT 264 colorectal liver metastases and 43 other liver lesions. The early and late arterial phase showed 240 and 277 liver lesions respectively. A certainty of the diagnosis was obtained in 63% and 85% at the early (EAP) and late arterial phase (LAP), respectively. Streak artifacts or liver segment truncation, or inadequate enhancement was responsible for the inability to see or to correctly adjudicate a lesion to a diagnosis in 27% and 15% of the cases at the EAP and LAP. The "worst-case scenario" yielded a Se and Sp of 58% and 51%, respectively, at EAP and 84% and 70%, respectively, at LAP.

CONCLUSION

On CBCT, EAP showed limited accuracy. LAP provided the best tumor detectability.

KEY POINTS

• The early arterial phase (EAP) yielded poor accuracy: Se = 58% and Sp = 51% (p < 0.0001). • The late arterial phase (LAP) phase yielded good accuracy: Se = 84% and Se = 70% (p = 0.02). • The probability of a correct diagnosis at the EAP was 60%.

Can cone-beam CT tumor blood volume predicts the response to chemoembolization of colorectal liver metastases? Results of an observational study

PURPOSE

To determine whether intraprocedural C-arm cone-beam CT (CBCT) parenchymal blood volume (PBV) can predict the response of colorectal cancer liver metastases (CRCLM) 2 months after irinotecan drug-eluting bead (DEBIRI) chemoembolization.

MATERIALS AND METHODS

This single-center observational study was compliant with the Helsinki Declaration and approved by our institutional review board. Thirty-four consecutive CRCLM patients referred for DEBIRI chemoembolization were enrolled between March 2015 and December 2016. Tumor size was assessed at baseline and 2 months after DEBIRI chemoembolization by multidetector CT (Response Evaluation Criteria in Solid Tumors RECIST 1.0), and PBV was measured before and after DEBIRI chemoembolization. Two independent readers reviewed all data. We determined the potential correlation (Spearman's rank correlation) between intraprocedural PBV values and tumor response at 2 months. The relationship between tumor response and PBV was studied using a mixed model. A logistic regression model was applied to study the relationship between patient "Responder/Non-responder" and PBV.

RESULTS

There was a strong correlation between baseline PBV or the percent change of PBV and the 2-month tumor response (rho = - 0.8587 (p = 0.00001) and rho = 0.8027 (p = 0.00001), respectively). The mixed model showed that an increase of 1 ml/1000 ml in PBV of a tumor before DEBIRI chemoembolization led to a 0.54 mm decrease in diameter (p < 0.005). A 1% decrease in PBV after DEBIRI chemoembolization resulted in tumor shrinkage of 0.75 mm (p < 0.005). The logistic regression model showed that patients with a 1% smaller mean decrease of PBV after DEBIRI chemoembolization had a 10% lower likelihood of achieving disease control (OR = 0.9, 95% confidence interval (CI) = 0.81-1; p = 0.0493).

CONCLUSION

Intraprocedural PBV may predict tumor response to DEBIRI chemoembolization.

KEY POINTS

• There is a strong relationship between the parenchymal blood volume (PBV) of colorectal liver metastases before DEBIRI chemoembolization and tumor response at 2 months. • Higher PBV values before DEBIRI chemoembolization correlate with greater tumor shrinkage, but only if the PBV decreases by more than 70% after DEBIRI chemoembolization. • Each increase of 1% in the mean decrease of PBV after DEBIRI chemoembolization resulted in a 10% lower likelihood of achieving disease control (OR = 0.9, 95% confidence interval (CI) = 0.81-1; p = 0.0493).

Local Ablative Therapies to Metastatic Soft Tissue Sarcoma

The approach to metastatic soft tissue sarcoma is complex and depends upon several factors, such as the extent of the disease, the histologic subtype of the primary tumor, the disease-free interval, patient status and comorbidities, and previous treatments. The effect of systemic chemotherapy is suboptimal, therefore local ablative therapies are often considered when the disease is limited, especially if confined to a single site/organ. Historically, surgery has been considered the treatment of choice for isolated lung metastases. This approach also has been extended to metastases in the liver, although a formal demonstration of its benefit has never been provided. Radiation therapy instead has been mainly used to obtain pain control and to reduce the risk of bone fracture and cord compression. Advances in techniques, such as the development of more precise conformational modalities and the employment of particles, may change the role of this modality in the strategic approach to metastatic soft tissue sarcoma. Recently, the use of interventional radiology in this scenario has expanded. Ablative approaches, such as radiofrequency ablation and cryoablation, have shown durable eradication of tumors. Catheter-directed therapies, such as hepatic artery embolization, are potential techniques for treating the patient who has multiple unresectable liver metastases. Understanding the timing and role of these three different modalities in the multidisciplinary approach to metastatic soft tissue sarcoma is critical to provide better care and to personalize the approach to the single patient.

Role of imaging for patients with colorectal hepatic metastases: what the radiologist needs to know

Surgical resection of colorectal metastatic disease has increased as surgeons have adopted a more aggressive ideology. Current exclusion criteria are patients for whom a negative resection margin is not feasible or a future liver remnant (FLR) of greater than 20% is not achievable. The goal of preoperative imaging is to identify the number and distribution of liver metastases, in addition to establishing their relation to relevant intrahepatic structures. FLR can be calculated utilizing cross-sectional imaging to select out patients at risk for hepatic dysfunction after resection. MRI, specifically with gadoxetic acid contrast, is currently the preferred modality for assessment of hepatic involvement for patients with newly diagnosed colorectal cancer, to include those who have undergone neoadjuvant chemotherapy. Employment of liver-directed therapies has recently expanded and they may provide an alternative to hepatectomy in order to obtain locoregional control in poor surgical candidates or convert patients with initially unresectable disease into surgical candidates.

The interventional radiologist role in treating liver metastases for colorectal cancer

Interventional radiologists (IRs) have an expanding role in the treatment of liver metastases from colorectal cancer. Increasing data on the ability to treat liver metastases with locoregional therapies has solidified this position. Ablative approaches, such as radiofrequency ablation and microwave ablation, have shown durable eradication of tumors. Catheter-directed therapies-such as transarterial chemoembolization (TACE), drug-eluting beads (DEB), Y90 radioembolization, intra-arterial chemotherapy ports, and isolated hepatic perfusion (IHP)-are potential techniques for managing patients with unresectable liver metastases. Understanding the timing and role of these techniques in the multidisciplinary care of the patient is critical. Implementation of the IR clinic for consultation has enabled better integration of these therapies into the patient's overall care and has facilitated improved opportunities for clinical studies.

Ablative and catheter-directed therapies for colorectal liver and lung metastases

Increasing data on treatment of liver metastases with locoregional therapies have solidified the expanding role of interventional radiologists (IRs) in the treatment of liver metastases from colorectal cancer. Ablative approaches such as radiofrequency ablation and microwave ablation have shown durable eradication of tumors. Catheter-directed therapies such as transarterial chemoembolization, drug-eluting beads, yttrium-90 radioembolization, and intra-arterial chemotherapy ports represent potential techniques for managing patients with unresectable liver metastases. Understanding the timing and role of these techniques in multidisciplinary care of patients is crucial. Implementation of IRs for consultation enables better integration of these therapies into patients' overall care.

Temporary arterial embolization of liver parenchyma with degradable starch microspheres (EmboCept®S) in a swine model

BACKGROUND

This study aimed to evaluate the embolic properties, time to reperfusion, and histologic changes in temporary embolization of liver tissue with degradable starch microspheres (DSM) in a swine model.

METHODS

In four adult minipigs, DSMs were injected into the right or left hepatic artery on the lobar level until complete stasis of the blood flow was detectable angiographically. The time required to complete angiographically determined reperfusion was noted. The animals were killed 3 h after complete reperfusion, and samples were taken from the liver. Histologic examinations of the embolized liver parenchyma and untreated tissue were performed.

RESULTS

Hepatic arterial embolization using DSMs was technically successful in all cases, with complete blood flow stasis shown by control angiography. A single vial of DSMs (450 mg/7.5 ml) was sufficient to embolize a whole liver lobe in all cases. Angiography showed complete reconstitution of hepatic arterial perfusion after a mean time to reperfusion of 32 ± 6.1 min (range, 26-39 min). Hematoxylin and eosin staining showed no histologically detectable differences between untreated tissue and parenchyma embolized with DSMs except for mild sinusoidal congestion in one case. Indirect in situ DNA nick end labeling staining (TUNEL) showed only single positive hepatocytes, indicating apoptosis.

CONCLUSION

Temporary embolization of the hepatic artery using DSMs is feasible with complete reperfusion after 30 min in pigs. Even after complete arterial blood flow stasis, no extensive tissue damage to the embolized liver parenchyma was observed at histologic examinations in this short-term study.

Current status of imaging and emerging techniques to evaluate liver metastases from colorectal carcinoma

Colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. Liver is a common site of tumor spread and in approximately 30% of the cases; synchronous liver disease is present at the time of diagnosis. Early detection of liver metastases is crucial to appropriately select patients who may benefit from hepatic resection among those needing chemotherapy, to improve 5-year survival. Advances in imaging techniques have contributed greatly to the management of these patients. Multidetector computed tomography is the most useful test for initial staging and in posttreatment surveillance settings. Magnetic resonance imaging is considered superior to multidetector computed tomography and positron emission tomography for the detection and characterization of small lesions and for liver evaluation in the presence of background fatty liver changes. Positron emission tomography-computed tomography has a problem-solving role in the detection of distant metastasis and in posttreatment evaluation. The advanced imaging methods also serve a role in selecting appropriate patients for radiologically targeted therapies and in monitoring response to conventional and novel therapies.

Locoregional therapies for metastatic colorectal carcinoma to the liver--an evidence-based review

The liver is the most common visceral site of colorectal cancer metastasis and recurrence. Given that only 25% of patients with colorectal liver metastases are amenable to curative surgical resection at initial diagnosis, locoregional intra-arterial therapies including hepatic arterial infusion chemotherapy, conventional transarterial chemoembolization, drug-eluting-bead transarterial chemoembolization, and radioembolization have increasingly developed as viable treatment options. The rationale, efficacy, safety, and toxicity of each of these therapies are reviewed and stratified based on current evidence.

New advances in local therapy for colorectal cancer metastases to the liver

SUMMARY 

The liver is the most common site of metastasis from primary colorectal cancer (CRC), and liver metastasis represents a major cause of morbidity and mortality for patients with primary CRC. Of patients with metastatic CRC that is confined to the liver, only a minority of patients are candidates for potentially curative surgical resection. In addition, to the very well-established modalities of surgery and thermal ablation, several newer locoregional therapies are available for the treatment of hepatic metastases, including stereotactic body radiotherapy, radioembolization and chemoembolization. Small prospective studies evaluating these treatments show promising response rates and local control in the first-line and salvage settings. Further randomized trials are required for a more rigorous assessment of the benefit and optimal setting in which these therapies should be used in patients with CRC liver metastases.

Options for metastatic colorectal cancer beyond the second line of treatment

Colorectal cancer is the third most common cancer, with recent advances in the management of unresectable metastatic lesions. The aim of this review is to discuss the remaining options for heavily pretreated patients with unresectable metastatic colorectal cancer. Beyond second-line treatment, two epidermal growth factor receptor (EGFR) inhibitors, cetuximab and panitumumab, have a demonstrated clinical interest in patients with KRAS wild-type tumours. However, few data exist in patients pretreated with an anti-EFGR and who are being rechallenged with anti-EGFR drugs. Reintroduction of chemotherapy should be considered. In September 2012, regorafenib, a multi-kinase inhibitor was approved by the US Federal Drug Administration for patients refractory to other standard treatments. In the case of metastases limited to the liver, transarterial chemoembolization, hepatic artery infusion and radioembolization could also be discussed in selected patients. With the multiplication of therapeutic options in first-line, second-line treatment, and beyond, the concept of subsequent lines of chemotherapy should be replaced by a multiline strategy, dependent on the patient and on tumour biology. A better understanding of the tumour biology and predictive factors for the response to these therapies is needed, and further strategic trials are urgently warranted.

MDCT findings after hepatic chemoembolization with DC-beads: what the radiologist needs to know

Transcatheter arterial chemoembolization with drug-eluting beads (TACE-DC-beads) is a new local treatment for primary or metastatic liver tumors. Despite technical efforts to achieve highly selective embolization of the tumor-supplying vessels, small, or large insults to the non-tumorous parenchyma are inevitably induced by the embolic materials or procedure itself. Parenchymal changes following TACE-DC-beads include bile duct injuries (bile duct dilatation, periportal edema, and bilomas), obliteration of intrahepatic portal vein branches, hypodense ill-defined areas, and perilesional parenchymal enhancement. The radiologist must be familiar with the changes induced by this treatment in order to distinguish therapeutic effect and collateral findings from complications and residual or recurrent tumor.

Therapeutic effect and tolerability of gelatin sponge particle-mediated chemoembolization for colorectal liver metastases: a retrospective study

Background

Colorectal cancer (CRC) is one of the most common cancers worldwide. The majority (approximately 60%) of patients with CRC will eventually develop liver metastases, which remain the most common cause of mortality in these patients. This study aimed to evaluate the therapeutic effect and tolerability of gelatin sponge particle (GSP)-mediated chemoembolization in the treatment of colorectal liver metastases after systemic chemotherapy failure.

Methods

This was a single-center retrospective study of 15 patients with colorectal liver metastases, who underwent GSP-mediated chemoembolization with 50 mg of lobaplatin during the period December 2009 to December 2010 in the Department of Interventional Radiology, Affiliated Zhongshan Hospital of Dalian University. Clinical data were retrieved, and the therapeutic effect and tolerability of the treatment were evaluated.

Results

All 15 patients with colorectal liver metastases completed the GSP-mediated chemoembolization. The therapeutic effect and tolerability were evaluated 3 months after the initial procedure. The tumor lesions in all patients showed various levels of necrosis and shrinkage. According to the Response Evaluation Criteria in Solid Tumors (RECIST), one patient achieved complete response (CR), eleven patients achieved partial response (PR), and three patients achieved stable disease (SD). The overall response rate (CR + PR) was 80%.

Conclusions

GSP-mediated chemoembolization is well tolerated and has a good short-term response rate (80%) in the treatment of colorectal liver metastases after systemic chemotherapy failure. Collectively, further study of the long-term effect of GSP-mediated chemoembolization in colorectal liver metastasis in a large cohort is warranted.

Repetitive chemoembolization of hypovascular liver metastases from the most common primary sites

AIM

To evaluate tumor response in patients with hypovascular liver metastases from the most common primary sites treated with chemoembolization.

MATERIALS & METHODS

Chemoembolization was performed in 190 patients (five groups) who had hypovascular liver metastases from the colon (n = 66), breast (n = 40), uveal malignant melanoma (n = 20), pancreas (n = 48) and stomach (n = 16). Surgical resection of primary sites had been performed for all included patients. Tumor response, survival statistics from the first chemoembolization using Kaplan-Meier method and progression rate of embolized lesions were evaluated by analysis of variance with Tukey's post hoc test.

RESULTS

Multiple comparison between the groups showed no statistical significant difference in local tumor response (H: 9.23; p > 0.05). Survival indices of the patients, including survival rate, progression-free survival rate, median survival time and time to progression, demonstrated significant difference between the groups during the follow-up period (H: 9.7; p = 0.045). The progression rate of treated liver metastases from colon, breast, uvea, pancreas and stomach were 16.6, 17.5, 30.0, 25.0 and 32.0%, respectively (p = 0.002).

CONCLUSION

Hypovascular liver metastases treated with chemoembolization may demonstrate equal local response, but are significantly different in rate of progression and survival.

Repeated bland-TAE using small microspheres injected via an implantable port-catheter system for liver metastases: an initial experience

PURPOSE

The purpose of this pilot study was to assess the effectiveness of repeated bland-TAE using small-size microspheres for liver metastases. To date, there have been no publications as to whether bland-TAE could be effective for nonhypervascular liver tumors.

METHODS

Bland-TAE with 100-μm, calibrated microspheres was performed in two chemoresistant patients: one with colorectal metastases and the other with gastric metastases. Both patients had multiple tumors in the entire liver. An implantable port-catheter system was placed in the hepatic artery to conduct repeated embolizations, thereby achieving enough efficacies. Microspheres were injected via the port until the disappearance of the tumor stains. Angiographies via the port were conducted 1, 3, 7, and 14 days after bland-TAE to evaluate the patency of the hepatic artery.

RESULTS

The hepatic artery started to recanalize 1 day after TAE and tumor stains appeared again during the 14 days. In both patients, bland-TAE was repeated four times in intervals of 14-21 days. The enhanced CTs showed necrotic changes and the decrease in size of the tumors. The serum CEA level decreased from 2,989 to 70 ng/ml and from 174 to 48 ng/ml, respectively. Bilomas and a liver abscess developed as complications.

CONCLUSIONS

Repeated bland-TAE using 100-μm microspheres injected via an implantable port-catheter system could be effective for liver metastases, although the caution of biliary injury is needed.

Intra-arterial therapies for metastatic colorectal cancer

Intra-arterial therapies for unresectable hepatic metastases from colorectal cancer include radioembolization (RE) with yttrium-90 microspheres, transarterial chemoembolization (TACE), hepatic arterial infusion, and percutaneous hepatic perfusion using an organ isolation system. In this article, we discuss our approach toward treatment selection, followed by details of how RE and TACE are performed at our institution.

Colorectal liver metastases: state of the art imaging

Colorectal cancer is a leading cause of death with mortality determined predominately by metastatic involvement of the liver. Treatment of liver metastases continues to evolve and imaging plays an essential role in initial staging, preoperative planning, and treatment monitoring. This review article discusses the current role of imaging in the management of patients with colorectal liver metastases. Particular challenges such as hepatic steatosis, disappearing metastases, and following treated lesions are addressed.

Superselective particle embolization enhances efficacy of radiofrequency ablation: effects of particle size and sequence of action

PURPOSE

To evaluate the effects of particle size and course of action of superselective bland transcatheter arterial embolization (TAE) on the efficacy of radiofrequency ablation (RFA).

METHODS

Twenty pigs were divided into five groups: group 1a, 40-μm bland TAE before RFA; group 1b, 40-μm bland TAE after RFA; group 2a, 250-μm bland TAE before RFA; group 2b, 250-μm bland TAE after RFA and group 3, RFA alone. A total of 40 treatments were performed with a combined CT and angiography system. The sizes of the treated zones were measured from contrast-enhanced CTs on days 1 and 28. Animals were humanely killed, and the treated zones were examined pathologically.

RESULTS

There were no complications during procedures and follow-up. The short-axis diameter of the ablation zone in group 1a (mean ± standard deviation, 3.19 ± 0.39 cm) was significantly larger than in group 1b (2.44 ± 0.52 cm; P = 0.021), group 2a (2.51 ± 0.32 cm; P = 0.048), group 2b (2.19 ± 0.44 cm; P = 0.02), and group 3 (1.91 ± 0.55 cm; P < 0.001). The greatest volume of ablation was achieved by performing embolization with 40-μm particles before RFA (group 1a; 20.97 ± 9.65 cm(3)). At histology, 40-μm microspheres were observed to occlude smaller and more distal arteries than 250-μm microspheres.

CONCLUSION

Bland TAE is more effective before RFA than postablation embolization. The use of very small 40-μm microspheres enhances the efficacy of RFA more than the use of larger particles.