According to a recent article published in the journal Cancer, the combination of transcatheter chemoembolization (TACE) and percutaneous ethanol injection (PEI) therapy is superior to PEI alone for the treatment of patients with small hepatocellular carcinomas.
Hepatocellular carcinoma (HCC) is a cancer of the liver. Approximately 85% of all primary liver cancers are HCC. HCC treatment depends on the size and number of tumors, condition of the liver, extent of disease and the patient’s age and general health. Treatment may include surgery, radiation therapy, immunotherapy, chemotherapy or a combination of therapies. Since HCC is difficult to diagnose in its earliest stages, long-term survival is poor and recurrence is frequent. Consequently, researchers are often exploring new strategies for the treatment of HCC.
Both TACE and ethanol (alcohol) injection have demonstrated anti-cancer properties for HCC tumors. TACE involves surgically implanting a catheter into the major artery (hepatic) that supplies blood to the liver. Through this catheter, chemotherapy drugs are injected directly into the liver. This augments the anti-cancer effects of chemotherapy beyond the effects offered by systemic (full body) delivery through a few mechanisms: 1) the chemotherapy agent does not become diluted by mixing with the rest of the blood from the body prior to reaching the cancer, 2) the chemotherapy agent is not broken down in the body through biochemical processes prior to reaching the cancer, 3) larger amounts of the chemotherapy agent can reach the cancer with fewer associated systemic side effects.
Following intra-arterial chemotherapy administration, a small gelatin sponge is placed into the hepatic artery to block blood flow to the cancer. This reduces the volume of blood in the cancer, which allows the chemotherapy agent to spread throughout the cancer and remain there in sufficient concentrations.
Percutaneous ethanol injection is a procedure in which ethanol is injected directly into the cancer(s). One to three needles are placed through the skin into the cancer through CT image guidance. Ethanol, which kills cancer cells through dehydration, coagulation and clot formation, is then administered through the needles, which are left in place for 5 to 10 minutes to prevent reflux of the ethanol. The reduced blood volume achieved by TACE augments the anti-cancer effects of ethanol in the same way it augments chemotherapy.
Researchers from Japan recently conducted the first clinical trial evaluating the efficacy of combining TACE with PEI versus PEI alone in 52 patients with small HCC lesions. In this study, all patients had one to three lesions that measured less than 3 centimeters in diameter. Half of the patients were treated with both TACE and PEI, while the other half were treated with PEI alone. Three years following treatment, the group of patients who received the combination therapy had a 20% reduced incidence of residual disease (cancer growth at the site of the original cancer) and a 60% reduced incidence of new cancer lesions compared to patients receiving PEI alone. The overall survival rates at 1, 3, and 5 years following therapy were 100%, 81% and 40.4%, respectively in patients treated with TACE-PEI and 91.3%, 65.9% and 37.7%, respectively in patients treated with PEI only.
It is important to note that patients with lesions measuring less than 2 centimeters in diameter achieved the most benefit from treatment with TACE-PEI compared to PEI alone. Three years following therapy in this subgroup of patients, not one patient treated with the TACE-PEI combination had any detectable residual disease, compared with 31.8% of those treated with PEI alone. In addition, all patients with lesions less than 2 cm treated with TACE-PEI were alive at 3 years following therapy, compared to 62.4% of these patients treated with PEI alone.
These results indicate that TACE-PEI improves survival compared with PEI alone in patients with small HCC, particularly those smaller than 2 cm. Future clinical trials will help to further establish the role of combination TACE-PEI therapy in the treatment of small HCC tumors.
Patients with HCC may wish to speak with their physician about the risks and benefits of participating in a clinical trial evaluating TACE-PEI combination therapy or other promising therapeutic approaches.
( Cancer, Vol 92, No 6, pp 1516-1524, 2001)