They are soaked with drugs to target only the tumor, researchers explain
TUESDAY, Jan. 20 (HealthDay News) -- A minimally invasive therapy that uses beads soaked with anti-cancer agents has been successful at halting liver tumors, according to new studies.
Transarterial chemoembolization (TACE) attacks liver tumors on two fronts. Microspheres, or beads, combined with cancer-killing chemotherapeutic agents are delivered to the blood vessel feeding the tumor. While the chemo attacks the cancer, the microspheres get stuck in the vessels and choke off the blood supply to the tumor -- a process called embolization.
While surgically removing a tumor is the most effective way to treat one, this is not an option for most liver cancer patients. In two out of three instances, the size or location of the liver cancer prevents surgery, or the tumor has grown into the blood vessels. Typically, only a quarter of people with liver cancer survive two years after diagnosis.
TACE holds promise, because the tumor, rather than the entire body, receives the chemotherapy directly. It is used to slow, not cure, the disease, but successful improvements in the beads and the procedure were expected to be presented in three separate trials this week at the annual International Symposium on Endovascular Therapy (ISET) in Hollywood, Fla.
In the first study, done at St. Joseph's Hospital and Medical Center in Tampa, Fla., 10 of 11 liver cancer patients given beads that released the chemo drug doxorubicin were alive two years after the procedure. Ten of the 13 people patients who had colorectal cancer that spread to the liver and were given the same treatment also were alive after two years.
The "LC Beads," as they were called, also did not cause systemic side effects.
"There is definitely a chance of cancer cure with this procedure beyond just palliation," Dr. Glenn Stambo, vascular and interventional radiologist at St. Joseph's, said in an ISET news release. "The more isolated the tumor and its blood vessel feeders, the better the chance for a complete cure."
An Italian study showed positive results with "HepaSphere" beads, which expand once stuck in the vessels to better block blood flow while also delivering chemo agents directly into the tumor. More than 86 percent of the 53 liver cancer patients in that trial showed a complete response to the therapy after six months.
"Patients who still had good liver function and who had tumors in only one lobe of the liver did better with this treatment," Dr. Maurizio Grosso, chairman of the department of radiology at Santa Croce and Carle Hospital in Cuneo, Italy, said in the same news release. "We're hopeful that treatment with HepaSphere will be an improvement over traditional chemoembolization."
Even without chemotherapy added to the beads, the embolization technique showed promise in a different Italian study. About half of 34 primary liver tumors shrunk within one month in patients given non-chemo "Embozene" microspheres alone. The other half showed no signs of tumor growth.
In a group of 16 tumors observed over the next six to 12 months, two completely disappeared, seven shrunk, two remained the same size, and five grew. Those that grew, though, were still small enough for additional localized treatments to be tried.
"One of the main benefits of Embozene microspheres is the precise, well-calibrated sizing, which match the small blood vessels that feed the tumors. The larger the particles used, the further away the embolization from the tumor and the less effective the treatment will be," Dr. Franco Orsi, chief of interventional radiology at the European Institute of Oncology in Italy, said in the same news release. "Moreover, embolization without drugs usually causes few or no post-treatment side effects, and patient can usually be discharged the next day."
The U.S. National Cancer Institute has more about liver cancer.
-- Kevin McKeever
SOURCE: International Symposium on Endovascular Therapy, news release, Jan. 18, 2009
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