YOUR HEALTH: Using microbubbles to improve radiation treatments

PHILADELPHIA, Pennsylvania – When it comes to treating illnesses it's often not only the medicine you're getting.   It's how you're getting it.

They're called microbubbles: small bubbles with a solid shell and a gas inside.

Doctors have found a way for them to work in tandem with radiation treatment.  It's new hope on the horizon for the millions suffering from advanced liver disease.

"By getting access just to the tumor with the blood supply by the catheter and depositing beads only within the tumor, the hope is we're cooking those tumors, but not the surrounding liver. Not the healthy tissue," explained medical researchers John Eisenberry.

Liver cancer is one of the most deadly cancers, largely due to Hepatitis "C".   In addition, an increase in fatty liver disease can cause further complications.

"Someone who has obesity, diabetes, may not appreciate any symptoms, so it's very important that they're checked by their primary care physician and referred to a hepatologist," said Dr. Jesse Civan, director of the Jefferson Liver Tumor Center.

Because liver cancer is so deadly, researchers are testing the microbubbles.

Glass radiation beads are inserted into the liver, then the microbubbles are infused into the blood.

"We can focus our ultrasound beam only on the liver tumor while the bubbles are circulating everywhere in the body, the ultrasound focuses just on the tumor itself and pops the bubbles only within the tumor itself," said Eisenbery.

When the bubbles pop, they boost the radiation.

Getting them into the body is similar to other types of medical procedures.

"For the patients it's like having an angiogram done and for those patients who've had cardio catheterizations, it would be similar, so you can access the blood vessel either in the wrist or in the groin," said Dr. Colette Shaw, interventional radiologist.

NEW TECHNOLOGY:   Microbubbles were originally developed to help improve ultrasound imaging.   However, being able to 'pop' oxygen-filled microbubbles within tumors using beams of ultrasound presented researchers with an opportunity.   Most solid tumors are oxygen-deficient, in part because they quickly outgrow the supply of oxygen-carrying blood vessels that can penetrate the tumor mass.   That lack of oxygen also makes tumors more resistant to radiation, which is why trying to flush tumors with oxygen became such a prized goal in the field.   In this study, John Eisenbrey, Ph.D., and colleagues showed that popping the microbubble with ultrasound immediately prior to radiation treatment could triple sensitivity of the cancer to radiation.   It also nearly doubled the survival times in mice from 46 days with placebo, nitrogen-filled microbubbles, to 76 days with oxygen-filled microbubbles. (Source: https://www.jefferson.edu/university/news/2018/01/29/oxygen-microbubbles-may-improve-radiation-for-breast-cancer.html)

The early findings, still in clinical trials, show good response.

"So the hope with a lot of these therapies is you first destroy that blood supply and that eventually starves the tumor and then it begins to shrink over time," said Eisenbery.

If this story has impacted your life or prompted you or someone you know to seek or change treatments, please let us know by contacting Jim Mertens at jim.mertens@wqad.com or Marjorie Bekaert Thomas at mthomas@ivanhoe.com.