Transcatheter arterial chemoembolization (TACE) of the liver is a proposed alternative to conventional systemic or intra-arterial chemotherapy, and to various nonsurgical ablative techniques, to treat resectable and nonresectable tumors. The rationale for TACE is that infusions of viscous material containing one or more antineoplastic agents may exert synergistic effects: cytotoxicity from the chemotherapy, potentiated by anoxia in the infarcted region. The beneficial effect of chemoembolization may be further potentiated by labeling the infusate with radioactive isotopes for localized radiotherapy. The liver is especially amenable to such an approach, given its distinct lobular anatomy, the existence of two (2) independent blood supplies, and the ability of healthy hepatic tissue to grow and thus compensate for tissue mass lost during chemoembolization. Another rationale is that TACE delivers effective local doses, while possibly minimizing systemic toxicities associated with oral or intravenous chemotherapy.
Chemoembolization is often used for hepatocellular carcinoma and neuroendocrine cancers of the liver. According to available literature, chemoembolization (TACE) may be indicated for symptomatic treatment of functional neuroendocrine cancers (i.e., carcinoid tumors and pancreatic endocrine tumors) involving the liver, in persons with adequate hepatic function (bilirubin < 2 mg/dl, absence of ascites; no portal vein occlusion; and tumor involvement of < 65 % of liver). For carcinoid tumors, TACE is indicated only in persons who have failed systemic therapy with octreotide to control carcinoid syndrome (e.g., debilitating flushing, wheezing and diarrhea). The safety and effectiveness of chemoembolization for breast cancer metastases is unknown as only case reports and series have so far been reported. The largest series reported in a 2008 abstract was of 217 patients but this as not a prospective study.
In a comparative study with the three drugs versus mitomycin and doxorubicin for HCC, no advantage was found for the three drugs. For neuroendocrine carcnoma, a comparative study found that: “Chemoembolization was not associated with a higher degree of toxicity than bland embolization. Chemoembolization demonstrated trends toward improvement in TTP, symptom control, and survival. Based on these results, a multicenter prospective randomized trial is warranted.”
The Society of Interventional Radiology (SIR, 2009) states that chemoembolization has shown promising early results with some types of metastatic tumors. The evidence in the current medical literature is insufficient to demonstrate the efficacy of TACE or TAE for the treatment of liver metastases from other primary tumors, including but not limited to breast cancer, colorectal cancer, and other tumors of unknown primary sites. Metastatic disease to the liver from tumors other than primary neuroendocrine tumors is generally treated with surgery, chemotherapy, or both. First-line therapy for colorectal hepatic metastasis is treatment with systemic chemotherapy followed by radiofrequency ablation (RFA) or cryosurgical ablation if systemic therapy fails or is not an option.
For NET there is a trial: Best Therapy for Patients With Neuroendocrine Tumors (BESTTHERAPYNET) in Germany. It is a prospective observational study containing three arms comprising different therapeutic measures to treat patients with neuroendocrine tumors in advanced stages. The therapy arms include local ablative therapy such as TACE or SIRT, surgery and RFA with peptide receptor radiotherapy. This is not a randomized study. Observationsl studies are not phase I or II. It is a research method designed to draw inferences about the possible effect of exposure on an established outcome (e.g. a disease, a therapy) without the investigator’s intervention.
Nabil M, Gruber T, Yakoub D, Ackermann H, Zangos S, Vogl TJ. Repetitive transarterial chemoembolization (TACE) of liver metastases from renal cell carcinoma: local control and survival results. Eur Radiol. 2008 Jul;18(7):1456-63
M . Giroux , R . Baum , M . Soulen. Chemoembolization of Liver Metastasis from Breast Carcinoma .
Journal of Vascular and Interventional Radiology , Volume 15 , Issue 3 , Pages 289 – 291, 2004
Brown DB, Geschwind JF, Soulen M, et al. Society of Interventional Radiology (SIR) position statement on chemoembolization of hepatic malignancies. Society of Interventional Radiology. J Vasc Interv Radiol. 2006; 17(2):217-223.
Alexander T. Ruutiainen et al, Chemoembolization and Bland Embolization of Neuroendocrine Tumor Metastases to the Liver Journal of Vascular and Interventional Radiology
Volume 18, Issue 7, July 2007, Pages 847-855
Society of Interventional Radiology (SIR). Interventional radiology treatments for liver cancer. 2009. Available at: http://www.sirweb.org/patients/liver-cancer/