Microscopic glass beads have huge potential in treating liver tumors

How it works

Before treatment begins, Mahvash “maps” the patient’s liver.

“During this trial run, we inject contrast dye into the blood vessels, which identifies on X-ray the vessels that route blood out of the liver to the rest of the body,” he explains. “We then block off, or embolize, those vessels to prevent the TheraSpheres from traveling outside the liver during treatment and harming other tissues and organs.”

The pre-treatment mapping also allows doctors to customize bead delivery to the exact location and size of each patient’s liver tumors.

With mapping done, the patient goes home, then returns a week later for treatment. 

Mahvash starts by making a small slit in the patient’s groin. He then inserts a plastic catheter into the incision and snakes it up through the arteries to the liver. 

With the tip of the catheter in place, he injects millions of the radioactive beads directly into the tumors. Each microscopic bead is smaller than a grain of salt and is embedded with the radioactive isotope yttrium, also called Y-90. The beads lodge in the tumor vessels, stopping blood flow and emitting an extremely high dose of radiation to kill cancer cells.

The entire procedure is finished in about an hour. 

“The radiation kills the tumors from within,” Mahvash says, “and targets multiple tumors in the liver all at once, while sparing healthy liver tissue.”

The tiny beads deliver up to 40 times more radiation than conventional cancer radiation therapy, which uses a machine to aim high-energy radiation beams from outside the body into the liver. 

Conventional radiation is given five days a week for several weeks. TheraSpheres are typically delivered in one session. 

The beads will continue to release radiation over the course of two weeks following treatment, gradually decreasing to insignificant levels and with few side effects. 

Patients go home about three hours after the treatment and can resume their regular activities in two days. The most common side effect is two weeks of fatigue, the same as traditional radiation. 

“This minimally invasive and precise procedure has been shown to improve patients’ quality of life and increase their life expectancy,” says Mahvash.

“It allows us to treat a very difficult disease in an elegantly simple way.”    

Future uses

Besides treating colon cancer that has spread to the liver, TheraSpheres have proven useful in treating primary liver cancer that originates in the liver.

Researchers are now starting to think about how the technology can help handle other forms of cancer. Early studies show kidney cancer may be their next target. The blood supply to the kidneys is very rich, which could make them good candidates for the irradiated beads.

“The more vascular the tumor,” Mahvash says, “the more beads will get concentrated in the tumor, and the better the effect.”

Life-extending procedure

Treating colon cancer that’s spread to the liver with radiation-containing beads is considered palliative, meaning it typically does not provide a cure, but can help slow down or halt the growth of the disease and alleviate symptoms.

“Some patients who are given a window of six to 10 months to live end up living significantly longer,” Mahvash says. “This means more time to attend a high school or college graduation, walk a daughter down the aisle, or see a grandchild born.”

Not long after her TheraSphere treatment, Elsie felt well enough to enjoy a night on the town with her husband. The couple celebrated their 46th wedding anniversary at a local restaurant and danced to the first song played at their wedding – “Misty” by Johnny Mathis. 

“We swayed and held each other and cried,” says Elsie, who’s looking forward to attending her granddaughter’s wedding later this year.

“Added time to life is priceless,” Mahvash says. “We want people facing this diagnosis to know about this treatment option.”