Unresectable hepatocellular carcinoma (HCC) is a condition that is commonly treated with transarterial chemoembolization (TACE). TACE works by embolizing the hepatic artery, the main blood supply to the HCC, while chemotherapy such as doxorubicin is given at the same time to a localized region of the liver. The chemotherapeutic agent is typically given with lipiodol, which is a lipid soluble contrast agent that enhances the retention of the chemotherapeutic agent by the HCC. Many chemotherapeutic agents are water soluble; therefore, the emulsion formed by mixing with lipiodol often leads to a somewhat unstable combination that can lead to shortened duration of action and increased release of the drug into the systemic circulation. Increased systemic exposure helps to shorten side effects such as nausea, vomiting, malaise, and fatigue. One new drug delivery system that aims to decrease side effects includes drug-eluting beads (DEBs).
DEBs are a type of drug delivery system that is being studied in highly vascular cancers such as colorectal cancer and HCC. These beads are typically “loaded” with a certain type of chemotherapeutic agent and administered through a catheter by an interventional radiologist to a localized area of cancer. By using these beads to provide a potentially toxic medication such as doxorubicin to a more localized region of the body, there should be less risk of systemic toxicity. In addition, these beads allow for a more sustained release of the medication, which could aid in prolonging the amount of time cancer cells are exposed to a specific chemotherapy.
Since DEBs are a relatively new technology, there is somewhat limited data on its safety and efficacy in HCC. In one study that included 118 HCC patients treated with TACE-DEBs loaded with doxorubicin, there were limited side effects. Only 14% of patients experienced nausea and localized pain, while liver failure and/or dysfunction occurred in only 9% of patients. Efficacy results were also positive with a median overall survival of approximately 14 months, and 3 patients were actually able to meet transplantation criteria. An additional study comparing traditional TACE with TACE-DEBs loaded with doxorubicin showed a slightly higher response rate at 6 months with the DEB group; however, the difference was not statistically different. There was, however, a significant decrease in transaminitis and overall liver toxicity in the DEB group.
DEBs offer a new and innovative way to maximize the efficacy of chemotherapeutic agents while limiting the toxicities. As is usually the trend with new drug delivery systems in oncology, more clinical studies are needed in order to further investigate the true potential of DEBs in all cancers, especially HCC. If DEBs prove to be a viable drug delivery system in oncology, this could expand the role of many other chemotherapeutic agents in HCC.
Readers, we want to hear from you! Let us know in the comments section below.
- What other types of cancer do you think DEBs could be utilized in?
- What other types of chemotherapeutic agents do you think would be worthwhile testing using the DEB technology in HCC?