Chemoembolization – pro
Lay Summary: TACE is often used for hepatocellular carcinoma and neuroendocrine cancers of the liver.
This technique takes advantage of the fact that HCC is a very vascular (contains many blood vessels) tumor and gets its blood supply exclusively from the branches of the hepatic artery. This procedure is similar to intra-arterial infusion of chemotherapy. But in TACE, there is the additional step of blocking (embolizing) the small blood vessels with different types of compounds, such as gelfoam or even small metal coils. Thus, TACE has the advantages of exposing the tumor to high concentrations of chemotherapy and confining the agents locally since they are not carried away by the blood stream. At the same time, this technique deprives the tumor of its needed blood supply, which can result in the damage or death of the tumor cells.There is no established standard protocol for TACE.If the procedure is successful (>50% lipiodol uptake in necrotic tumor demonstrated on the postprocedural CT scan), the embolization is repeated in 6-8 weeks. If the lipiodol uptake is less than 50%, the authors repeat the CT scan in 6-8 weeks. If the size of the tumor is reduced, repeat TACE may be considered.The second TACE treatment should first be performed in previously untreated tumors.The third treatment completes a normal course, but further treatments are performed in patients with residual disease.
The type and frequency of complications of TACE and intra-arterial chemotherapy are similar. The potential disadvantage of TACE is that blocking the feeding vessels to the tumor(s) may make future attempts at intra-arterial infusions impossible. Moreover, so far, there are no head-to-head studies directly comparing the effectiveness of intra-arterial infusion versus chemoembolization. Studies in Japan have shown that TACE can downstage HCC. In other words, the tumors shrank enough to lower (improve) the stage of the cancer. From the practical point of view, shrinking the tumor creates the option for surgery in some of these patients. Otherwise, these patients had tumors that were not operable (eligible for operation) because of the initial large size of their tumors. More importantly, these same studies showed an improvement in survival in patients whose tumors became considerably smaller. In the U.S., trials are underway to see whether doing TACE before liver transplantation increases patient survival as compared to liver transplantation without TACE.
It is safe to say that TACE or intra-arterial chemoinfusion are palliative treatment options for HCC. However, they are not curative (Fewer than 50% of patients will have some shrinkage in tumor size. Further, they can be used only in patients with relatively preserved liver function. Several randomized trials have established this procedure as standard of care for hepatocellular cacrinoma and neuroendocrine carcinoma.
There is little evidence on what drugs are best. Studies of mitomycin of adriamycin are most common but many radiologists add ethidiol based on a comparative study, of Gelfoam and some also use cisplatin, also based on a study. Combination of four drugs are often used, without much data. Another unanswered question under study is whether to combine TACE with chemotherapy or Nexavar.
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EVIDENCE-BASED PRACTICE:
Calogero Cammà, Filippo Schepis, Ambrogio Orlando, Maddalena Albanese, Lillian Shahied, Franco Trevisani, Pietro Andreone, Antonio Craxì, and Mario Cottone
Transarterial Chemoembolization for Unresectable Hepatocellular Carcinoma: Meta-Analysis of Randomized Controlled Trials
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NCCN, melanoma, 2013