Treatment of patients with irresectable liver metastases from colorectal cancer by chemo-occlusion with degradable starch microspheres

Safety and efficacy of transarterial chemoembolization with degradable starch microspheres (DSM-TACE) in the treatment of secondary liver malignancies

Purpose

To evaluate the safety and efficacy of degradable starch microspheres (DSM) as embolic agents in transarterial chemoembolization (TACE) in the treatment of secondary liver metastases.

Methods

This was a national, multicenter observational study. Primary endpoints were safety and treatment response according to Modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria.

Results

A total of 77 DSM-TACE procedures were performed in 20 patients. Minor immediate adverse events (AEs) were epigastric pain with an incidence of 45.5% (35/77), and nausea and vomiting at an incidence of 23.4% (18/77). Delayed minor AEs were epigastric pain in 13/77 (16.9%) treatments and nausea and vomiting in 10 (13.0%) treatments. No severe AEs were documented. Therapeutic efficacy of DSM-TACE procedures according to mRECIST was as follows: complete response 0/77, partial response 17/77, stable disease 33/77 and progressive disease 6/77, no data was available for 21/77 treatments. Overall, objective response was achieved in 8 of 20 patients (40.0%).

Conclusion

DSM as embolic agent for TACE is safe in the treatment of liver metastases. An objective response in 40.0% of patients and disease control in 64.9% of procedures was achieved, and this should lead to further evaluation of DSM-TACE as treatment option for nonresectable liver metastases.

Intravital microscopic research of microembolization with degradable starch microspheres

Treatment efficacy in cancer patients using systemically applied cytostatic drugs is decreased by cytotoxic side effects, which limits the use of efficient dosages. Degradable starch microspheres (DSM) are used to apply drugs into blood vessels which supply the target organ leading to drug accumulation in the target organ by reduction of the blood flow. The present investigations show that DSM is a very effective embolization material leading to effective and enhanced accumulation of 5-FU within the liver tumor tissue of experimental induced liver cancer in rats. By using intravital microscopy, a rapid deceleration of the blood flow into the target organ is observed immediately after application of DSM. The microspheres are stepwise degraded in the direction of the systemic blood flow and are totally dissolved after 25 minutes. These stepwise processes leave the degraded material during the degradation process within the vessels leading to temporally reciprocal blood flow via some of the side-arms of the major blood vessels. By using DMS in transarterial chemoembolization (TACE), severe adverse side effects like postembolization syndrome are rarely observed when compared to other embolization materials. The complete degradation of DSM causes only a short-lasting temporary vascular occlusion, which allows a repeat application of DSM in TACE.

Advances in regional chemotherapy of the liver

INTRODUCTION

Primary and secondary liver tumors resemble some of the most common causes of cancer and represent a major clinical problem owing to the poor prognosis. First-line therapeutic concepts are mainly based on surgical resection and/or systemic chemotherapy (SCT). However, many patients are not suitable for surgery or have failed SCT, although the total tumor load is still limited, which makes a regional therapy approach appealing.

AREAS COVERED

This review focuses on different types of transarterial instillation of chemotherapy, which encompasses conventional and drug-eluting transarterial chemoembolization (TACE), hepatic arterial infusion (HAI) chemotherapy and isolated hepatic perfusion (ILP).

EXPERT OPINION

TACE can be regarded as the treatment of choice in patients with multinodular hepatocellular carcinoma, but it should still be performed as a lipiodol-based regimen, while the value of doxorubicin-eluting beads needs to be exploited in further randomized controlled trials (RCTs). For patients with colorectal liver metastases, HAI chemotherapy has been challenged by the advent of more effective SCT, but encouraging results have been observed for the combination of the most recent, active drugs given by means of HAI with SCT. Nevertheless, data from RCTs comparing SCT with this transarterial regional therapy approach, as well as with TACE and ILP, are urgently needed.

Chemoocclusion vs chemoperfusion for treatment of advanced hepatocellular carcinoma: a randomised trial

AIMS

Transarterial chemoembolization (TACE) can be associated with considerable toxicity and treatment-associated mortality. Transient transarterial chemoocclusion (TACO) using degradable starch microspheres (DSM) has been proposed as a potentially safer alternative while maintaining anti-tumour efficiency. In a randomised phase II trial TACO was compared to transarterial chemoperfusion without DSM (TACP).

METHODS

Seventy-four patients with advanced HCC were randomised to two treatment arms: (i) TACO (600-1200 mg DSM) and (ii) TACP. In both arms regional chemotherapy consisted of cisplatin (100 mg/m2) and doxorubicin (60 mg/m2). Both arms were corresponding in terms of age, gender, liver performance state, and tumour-stage. A maximum of six treatment cycles was applied in monthly intervals. Follow-up was performed in terms of tumour response, time to progression, survival and quality of life.

RESULTS

Tumour response rates did not differ significantly between the two treatment arms, however, there was a tendency towards higher response rates in the TACO arm (TACO vs TACP): partial response: 26 vs 9%, stable disease: 41 vs 55%, progressive disease: 33 vs 36%. Time to tumour progression (32 vs 27 weeks), and overall survival (60 vs 69 weeks) were not significantly different. Grade 4 adverse events were rare in both arms and treatment-associated mortality was not observed. In addition, there was no significant difference in terms of quality of life under therapy (EORTC).

CONCLUSION

TACO with DSM did not improve response or survival significantly compared to TACP in advanced non-resectable HCC.

[Transarterial chemoembolization of liver metastases of colorectal carcinoma using degradable starch microspheres (Spherex): personal investigations and review of the literature]

Since two decades transarterial chemoembolization (TACE) of liver metastases has been investigated in numerous studies. However, no standardized therapeutic procedure exists so far. The present study retrospectively investigated survival, response and side effects after TACE of liver metastases in 21 patients with colorectal cancer and results are compared with previous literature. A total of 68 TACE procedures were performed. A suspension of degradable starch microspheres (DSM, Spherex) and Mitomycin C was applied selectively into hepatic arteries via a transfemoral approach. DSM effect a temporary arterial occlusion. Follow-up studies were performed by contrast enhanced spiral computed tomography (CT). The median survival was 13.8 months. Therapeutic response (according to WHO) was observed only in three patients. The progression free interval was 5.8 months. Patients developed a postembolization-syndrome (abdominal pain, fever, nausea) and increased transaminases in 27-43% of all interventions. A gastric ulcer occurred after four, cholecystitis after two TACE. As already shown in most previous studies, regardless of the used agents, also this investigation underlines the moderate therapeutic effect of TACE on colorectal liver metastases. So far, no significant survival benefit has been shown in the literature and the response rates are rather limited. In general, complications of TACE seem to be rare, but should not to be underestimated. Compared to TACE with long or permanent arterial occlusion, postembolization syndrome seems to be less pronounced using DSM. As TACE is rather a palliative therapeutic approach, DSM therefore might be more suited. Further studies on TACE of liver metastases should focus on to the patients' quality of life.

Randomized phase II trial of embolization therapy versus chemoembolization therapy in previously treated patients with colorectal carcinoma metastatic to the liver

Locoregional therapies are useful in treating patients with colorectal cancer metastatic to the liver. A prospective randomized phase II trial of hepatic artery embolization versus hepatic artery chemoembolization was conducted to evaluate the response rates and toxicities of these therapies in the second-line setting. Patients were required to have biopsy-proven adenocarcinoma of the colon or rectum metastatic to the liver, with the liver as the sole or predominant site of metastatic disease. All patients had measurable disease and had failed at least one prior systemic chemotherapy treatment for metastatic disease. Patients were randomized to receive either embolization therapy with polyvinyl alcohol foam (Ivalon) administered as a single agent or chemoembolization using polyvinyl alcohol foam mixed with 750 mg/m2 of 5-fluorouracil and 9 million units of interferon. Drugs and embolic material were administered via the hepatic artery as a slurry with polyvinyl alcohol foam. Fifty eligible patients were enrolled. There were 24 patients in the chemoembolization arm and 26 in the embolization arm. Sixty-four percent of patients in both treatment arms had the liver as the sole metastatic site. The most common National Cancer Institute common toxicity criteria grade 3/4 toxicities were diarrhea (17%) and hepatic toxicity (8%). There was 1 (4%) treatment-related mortality due to a hepatic abscess. Four patients (15.4%) treated with embolization had a partial response (PR), and 5 patients (20.8%) treated with chemoembolization had a PR. The median survival for all patients was 11 months (95% confidence interval [CI], 8-15 months). Survival in patients with extrahepatic disease was 8 months (95% CI, 6-10 months). Survival in patients with liver-only metastases was 15 months (95% CI, 10-17 months). Embolization of the liver as second-line therapy in patients with liver-predominant metastases is safe and effective. Median survivals are comparable to other second-line therapies

Temporary unilateral microembolization of the lung-a new approach to regional chemotherapy for pulmonary metastases

BACKGROUND

Except in patients with resectable disease, treatment of pulmonary metastases is still disappointing. Regional chemotherapy may be a suitable method for delivering more effective doses to regionally confined tumors while minimizing systemic toxicity. We propose an unilateral chemoembolization of the lung applicable by endovascular method.

MATERIALS AND METHODS

An unilateral microembolization of the lung with degradable starch microspheres (DSM) alone (group 1) and combined with carboplatin (group 2) was performed on Sprague-Dawley rats (n = 12). Microcirculatory parameters were studied by in vivo videomicroscopy and radiological pattern on pulmonary angiogram.

RESULTS

After injection of DSM, mean embolization time in subpleural capillaries was 7.1 +/- 2.3 min, followed by a mean flow retardation of 14.3 +/- 4.6 min; 21.4 +/- 4.7 min after embolization, original flow of erythrocytes was observed demonstrating reperfusion and reversibility of microembolization. After reperfusion relative fluorescence measured in subpleural alveoli was 0.13 +/- 0.049 in group 1, 0.105 +/- 0.016 in group 2, and 0.11 +/- 0.036 in control group (NS). Alveolar septal diameter was 17.3 +/- 1.13 microm in group 1, 16.8 +/- 1.25 microm in group 2, and 16.6 +/- 1.08 microm in control group (NS), demonstrating neither altered permeability nor pulmonary edema. Pulmonary angiogram confirmed patency of the central pulmonary artery.

CONCLUSION

For the first time unilateral microembolization of the lung could be established in an experimental model. By injection of DSM, reversible embolization on arteriolar and capillary level could be demonstrated without occlusion of the main branches of the pulmonary arteries. Alveolar-capillary membrane disorder as symptom of early toxicity could not be detected even with additional application of carboplatin.

Global approach to hepatic metastases from colorectal cancer: indication and outcome of intra-arterial chemotherapy and other hepatic-directed treatments

Liver metastases of colorectal cancer is present in more than 20% of new diagnosed patients and in 40-60% of relapsed patients. It is a life-threatening prognostic aspect. Hepatic resection, when possible, is the best therapeutic modality, although the overall survival rate is still low (30%). Angiography and intraoperative ultrasonography are useful for resection. The number of hepatic metastases and the surgical margin are probably the most significant prognostic factors. Colorectal cancer may spread predominantly to the liver making regional treatment strategies viable options. Subtotal hepatic resections and segmentectomies are potentially curable procedures for single or small numbers of hepatic metastases without other sites of disease. However, there have been no prospective randomized trials comparing patients with unresected liver metastases and resected metastases. Regional chemotherapy with floxuridine seems usefull combined with hepatic resection or as palliative therapy. Gastric ulcer and biliary sclerosis are the main related toxicities. Patients with localized, unresectable hepatic metastases or concomitant bad medical condition may be candidates for radiation, percutaneous ethanol injection, cryosurgery, percutaneous radiofrequency, hypoxic flow-stop perfusions with bioreductive alkylating agents, hepatic arterial ligation, embolization and chemoembolization. These new hepatic-directed modalities of treatment are being investigated and may offer new approaches to providing palliation and prolonging survival. This review will report the possibilities of intra-arterial chemotherapy and other novel hepatic-directed approaches to the treatment of liver metastases from colorectal cancer.

Polymeric implants for cancer chemotherapy

Cancer chemotherapy is not always effective. Difficulties in drug delivery to the tumor, drug toxicity to normal tissues, and drug stability in the body contribute to this problem. Polymeric materials provide an alternate means for delivering chemotherapeutic agents. When anticancer drugs are encapsulated in polymers, they can be protected from degradation. Implanted polymeric pellets or injected microspheres localize therapy to specific anatomic sites, providing a continuous sustained release of anticancer drugs while minimizing systemic exposure. In certain cases, polymeric microspheres delivered intravascularly can be targeted to specific organs or tumors. This article reviews the principles of chemotherapy using polymer implants and injectable microspheres, and summarizes recent preclinical and clinical studies of this new technology for treating cancer.

Positron emission tomography with F-18-fluorodeoxyglucose to evaluate the results of hepatic chemoembolization

BACKGROUND

Positron emission tomography (PET) using F-18-flurodeoxyglucose (18FDG) is an imaging modality allowing direct evaluation of cellular glucose metabolism. The purpose of this study was to examine the role of 18FDG-PET in monitoring chemoembolization therapy of patients with liver metastases from adenocarcinoma.

METHODS

Thirty-four hepatic lesions in 4 patients were evaluated with 18FDG-PET before and 2-3 months after interventional therapy. All patients underwent transcatheter arterial chemoembolization. A total of nine PET studies were performed. Semiquantitative measurement of the metabolic activity of the lesions was performed using the standard uptake value (SUV) of 18FDG. Comparison was performed between sequential PET scans using Student's t test for paired data analysis. The PET findings were also compared with tumor marker levels measured at the time of the PET scans.

RESULTS

Twenty-five of 34 lesions had decreased 18FDG uptake (SUV = 8 +/- 2 vs. 3 +/- 1; P < 0.00001), as expected in successful tumor chemoembolization. These findings were associated with a significant decrease in serum tumor marker levels (86 +/- 4%; P < 0.05) after treatment. However, there were 3 new lesions, and 6 of the 34 lesions demonstrated persistent or increased 18FDG uptake after treatment (SUV = 8 +/- 2 vs. 13 +/- 3; P < 0.05), consistent with the presence of residual viable tumor. These findings led to further interventional therapy in all patients.

CONCLUSIONS

18FDG-PET allows monitoring of response to treatment with hepatic chemoembolization in patients with liver metastases from adenocarcinoma. PET is a useful diagnostic tool and has the potential to be used to guide further interventional therapy.