Cutting edge 3-D printing technology is helping Baton Rouge scientists and doctors make radiation treatments for cancer even safer.

Physicists working jointly with LSU and Mary Bird Perkins - Our Lady of the Lake Cancer Center are designing and then printing three-dimensional plastic aides for individual cancer patients.

These personalized aides help doctors precisely target tumors during radiation treatments.

“It’s a constant effort on everybody’s part to do that, and this is just one more tool we have,” said Dr. Robert Fields, a radiation oncologist at Mary Bird Perkins.

Physicists in LSU’s medical and health physics departments are among the leaders in the nation in using 3-D printing technology to create these devices, which are specifically made for a few tough-to-treat patients, said Wayne Newhauser, director of the university’s medical and physics program and the chief physicist at Mary Bird Perkins.

In addition to providing more personalized care, these locally made devices cost only a few hundred dollars compared with universal body models, which are more sophisticated, but can run $50,000 or more. And those sophisticated models aren’t always the right tool for the job, Newhauser said.

“These are in many cases nowhere near close enough to mimicking the patient’s actual anatomy,” Newhauser said.

Take Jeanette Mathews’ toe, for example. Last year, the 71-year-old Ponchatoula resident had a skin cancer form on her toe, which doctors told her was pretty rare.

Her doctors couldn’t remove it because “there was nothing there but the skin and the bone,” Mathews said.

Treating her dangerous tumor with radiation risked harming healthy tissue.

“He didn’t want radiation to go anywhere but that one little spot on my toe,” Mathews said.

In the past, she may have had to have her toe amputated, she said, but the physicists working on 3-D printing found another route.

After taking multiple CT scans to get the exact dimensions of her toe and tumor, the team designed and then printed a 3-D plastic device that allowed doctors to modify the radiation beam to hit just the tumor and avoid the rest of her toe.

“If you tried to make this yourself, it would be very difficult to fabricate this kind of material in three dimensions,” said Fields, who helped treat Mathews.

Mathews underwent six weeks of treatments, and after a year, she was deemed cancer-free. “I was really impressed by my doctor,” she said. “He wouldn’t accept anything but perfect.”

Most research of 3-D printing technology for cancer treatment is focused on creating models of cancer patients’ bodies to help doctors practice their radiation treatments, which are used to kill cancer cells left after surgically removing a tumor. The more precise the radiation is, the less surrounding healthy tissue is destroyed.

“It is our job to clean up the few cells, maybe millions of cells left behind (after surgery),” Fields said. “If you don’t eradicate those cells, you don’t get rid of every last cell, it will grow back.”

Cancer treatment has radically improved in the past 40 years. The five-year survival rate for all cancers in the 1970s was 50 percent, according to the National Institutes of Health. Today, the survival rate is approximately 68 percent.

Advances in radiation therapy are responsible for much of that improvement.

But in some difficult cases, radiation can hurt healthy areas of the body. For example, patients treated for breast cancer on the left side can have a small dose of radiation delivered to the heart, Newhauser said. Also, when fighting brain tumors, radiation to the brain can result in radiation necrosis, an area of dead tissue at the tumor site.

“It’s a rare side effect, but it can be fatal,” Newhauser said.

3-D printing can help reduce these side effects by creating models, called phantoms, of patients’ body parts so doctors can practice before treating the patient.

A need for a personalized phantom arose a few years ago when a patient at Mary Bird Perkins had his nose amputated because of an aggressive, life-threatening tumor. Because the hospital’s standard phantom had a nose, one of Newhauser’s LSU physics students worked to design a phantom specifically for the patient.

While they are able to create 3-D devices whenever needed for patients at Mary Bird Perkins, only about one in every 500 patients needs a personalized phantom.

“We think in the future as we develop more capabilities, this technology will be increasingly relevant to more patients,” Newhauser said. “There’s probably a several-year road until that really opens up.”