Teen with brainstem tumor undergoes her last treatment

Natalie Wright has had a tumor growing uncomfortably close to her brainstem for 15 years.

She and her father traveled to San Diego from Provo, Utah, six weeks ago in hopes of killing the relentless malignancy once and for all.

“I’ll definitely be happy when it’s finally gone, that’s for sure,” the 17-year-old said while sitting in the Ronald McDonald House near Rady Children’s Hospital.

Natalie is the first pediatric patient to undergo a full course of treatment at the $220 million Scripps Proton Therapy Center in Mira Mesa since it opened in February. On Friday, she received the last of 30 treatments designed to eradicate a cashew-sized cancerous growth that is putting pressure on nerves controlling brainstem functions such as chewing, swallowing, hearing and facial movements.

Three surgeries had managed to cut away much of the tumor, but surgeons could never quite get at a bit that impinged on the brainstem. The Wrights and their doctors at Scripps and Rady believe that protons, shot directly into the tumor through the back of the skull, can kill the growth without as much risk to nearby nerve cells.

“One can’t go digging into the brainstem, there’s too much injury that can happen,” said Dr. John Crawford, a pediatric neuro-oncologist with Rady.

Radiation, most often delivered via X-ray beams, is regularly used to kill tumors. But X-rays tend to carry right on through the tumor, delivering some radiation to healthy tissue behind the target. In contrast, protons can be made to stop inside the tumor and not come out the other side, resulting in comparatively less irradiation of nearby healthy tissue.

The incremental benefit between X-ray and proton is hotly debated for adults but less so for children.

Dr. Eric Hall, a scientist with the Center for Radiological Research at Columbia University Medical Center, published a paper in 2006 that concluded that children face 10 times the risk of developing secondary cancers due to radiation exposure when compared to adults. He also said radiation can stop healthy cells, especially neurons, from developing fully.

Proton therapy makes more sense for kids whose bodies are still developing, Hall said, but he added that treatment with a scanning beam is preferred. Older versions of the technology tend to scatter neurons during treatment, which can cause additional radiation exposure, he explained.

The Scripps center, which is owned by the company Advanced Particle Therapy, has the latest scanning technology, known as “pencil beam.” It uses powerful magnets to sweep a narrow beam of protons across a tumor, producing less scattering of radiation.

John Wright, Natalie’s father and a mechanical engineer specializing in three-dimensional graphics, said it was this precision, and his own research on proton therapy over the years, that made him willing to come to the center in Mira Mesa.

“He’s been studying protons since I was 2,” Natalie quipped.

The Wrights were surprised to receive the cellphone number of Dr. Andrew Chang, the radiation oncologist who would oversee Natalie’s treatment for Scripps and Rady.

When Natalie arrived six weeks ago, she said she loved the fact that Chang wears a different superhero shirt every day. Patients who undergo proton treatment for the brain must wear a specialized mask to hold their head steady while the beam is doing its work, and Chang’s team painted Wright’s with a Captain America design.

Natalie said the therapy generally has been painless.

“It felt like a bad sunburn on the surface of my skin at first, but now I don’t feel anything,” she said.

The same cannot be said for living with a brain tumor for most of her life.

When first detected, father and daughter explained, it was the size of a walnut and surgeons sliced most of it out when Natalie was only 2 years old.

But it quickly came back, growing to the size of a golf ball by the time Natalie was 4.

Because the tumor was growing so quickly, surgeons had to be more aggressive the second time around. That surgery had very serious consequences for Natalie and her family. Nerve damage caused her to lose her ability to swallow — and her gag reflex — for four years. She lost her sight in her right eye and hearing in her left ear. The left side of her body was partially paralyzed, a fact that changes, but never stops, her smile.

It will not be clear for at least two years whether the proton therapy stops the tumor from growing for good. Natalie will have a brain scan every three months for two years, then every six months for five years, to verify that the tumor has not expanded again.

The Wrights’ health insurance covered the treatment, and Chang said there is usually no problem getting proton therapy approved for pediatric cancer cases. But he added that state Medi-Cal insurance does not currently pay for the treatment.

“We, of course, think this is an option that should be available for all pediatric patients,” Chang said.

Scripps did not provide the total cost of proton treatment for pediatric brain tumors.

However, when the center opened in February, Scripps said that Medicare pays $47,000 for a course of 40 proton treatments for prostate cancer compared to $27,000 for the same number of X-ray-based treatments.