Targeted Microsphere Treatment for Liver Cancer Shows Promise

Known as selective internal radiation therapy (SIRT), this innovative treatment uses millions of microscopic radioactive beads referred to as SIR-Spheres, delivered via catheter, to target primary and metastic liver cancer while largely sparing healthy tissue.

Dr. Seza Gulec, a Florida International University (FIU) College of Medicine (Miami, FL, USA) professor of surgery and radiology/nuclear medicine, is a leading researcher in the development of this treatment and was the first in the United States to use SIRT in combination with chemotherapy for the treatment of liver cancers. "We are essentially using the tumors' blood supply to kill them, by infusing them with beta radiation through the targeted delivery of yttrium 90 resin microspheres,” said Dr. Gulec, who has continued to advance this radiomicrosphere therapy for liver cancer since joining FIU College of Medicine in August 2008. "With this approach, we are able to use a much higher dose of radiation to effectively reduce the size and activity of cancer tumors in the liver. From my experience of treating more than 200 patients, all have responded positively to this treatment with some patients leading longer lives.”

Clinical trials have confirmed that liver cancer patients treated with SIR-Spheres microspheres have response rates higher than those with other forms of treatment. In a recently completed clinical trial, reported on in May 2009 in the Journal of Nuclear Medicine (JNM), SIRT combined with chemotherapy was shown to be superior to chemotherapy alone in patients with colorectal cancer liver metastases.

"Of the nearly 150,000 Americans diagnosed with colorectal cancer every year, at least 60% will see their cancer spread to the liver,” said Dr. John Rock, founding dean and senior vice president for medical affairs for FIU College of Medicine. "That makes Dr. Gulec's advancements in the field of radiomicrosphere therapy an incredibly important step forward in cancer research.”

The new approach is also used to treat pancreatic cancer patients who have recurrent disease and liver metastases and incorporates SIRT. The safety and efficacy of combining systemic chemotherapy with SIRT and external beam TomoTherapy for surgically untreatable pancreatic cancer was recently reported in the Journal of Interventional Oncology (JIO).

"It is essential that we continue conducting clinical trials combining SIRT with chemotherapy and other liver-directed treatment modalities to perfect this treatment,” Dr. Gulec stated. "Radiomicrosphere therapy is increasingly considered earlier in the course of treatment as opposed to a last resort. But, there is also a need for the development of more uniform patient selection criteria for treatment planning and execution.”

In the fall of 2008, Dr. Gulec and his team of FIU researchers, based at Jackson North Medical Center (Miami. FL, USA), were the first in the United States to begin implementing an advanced three-modality/three-dimensional treatment planning for SIRT. Since the U.S. Food and Drug Administration (FDA) granted SIR-Spheres microspheres premarket approval in March 2002, more than 1,800 treatments have been performed at more than 50 U.S.-based oncology centers, reported Sirtex (Wilmington, MA, USA), developer of the SIR-Spheres.

Related Links:
Florida International University College of Medicine
Sirtex