Mike Chen, M.D., Ph.D., wields his scalpel with the deft touch of a highly trained neurosurgeon.

But Chen knows that in brain cancer treatment, the scalpel can only do so much.

“No matter how much we improve our surgical techniques, it’s not going to help our patients as much as we want,” Chen said. “That’s why we have to look beyond traditional treatments.”

The newest neurosurgeon to join City of Hope’s Brain Tumor Program, Chen brings expertise in a developing area of treatment: delivery of advanced therapies directly to brain tumors through tiny, implanted catheters.

It may seem like science fiction, but the technology has promise.

Chen learned firsthand about the techniques during a three-year research fellowship in surgical neurology at the National Institutes of Health, or NIH. Called high-flow microinfusion, the strategy represents a novel way to break through the blood-brain barrier, the natural defense system that walls off the brain from microbes and toxins — and, unfortunately, many therapeutic drugs.

Put simply, surgeons begin by creating a small opening in the skull and threading a narrow, flexible catheter to the cancer site. That catheter delivers cancer-fighting compounds directly to tumor tissue.

At the NIH, Chen worked with physicians who were the first to investigate gene therapy vectors delivered through high-flow microinfusion to fight malignant gliomas, the most common form of primary brain cancer.

Now, at City of Hope, Chen will use the investigative technique to deliver gene therapy vectors and nanoparticles — designer molecules that can carry a potent drug payload — to metastatic brain tumors. Such metastatic tumors are cancers that have spread from another site in the body where they began, such as the breast.

If it develops as Chen hopes, the research will bring renewed hope for patients. Today, most brain metastases respond poorly to chemotherapy due to the blood-brain barrier, and only certain tumor types respond to radiation therapy, Chen said. And when removed surgically, such tumors often come back.

Chen relishes the challenge and believes in the therapeutic tools developing before him. “I think in the next 10 to 15 years, gene therapy will come around,” he said, “and one of the ways we’ll use it is through direct delivery to the brain.”

Chen has a flair for the futuristic. While in the midst of getting his bachelor’s degree at Pennsylvania State University and medical degree at Thomas Jefferson University through a combined, six-year program, he obtained a master’s degree in biomedical engineering at Johns Hopkins University.

“I was originally interested in designing neuroprostheses [artificial devices that improve or replace impaired parts of the nervous system]. I guess I watched a little too much ‘Six Million Dollar Man’ on TV,” Chen said with a laugh. Over time, however, he realized the body’s neurologic systems were too complicated to be harnessed with modern computers. He preferred to pursue a field where he could make a difference today — so he opted for an internship in general surgery.

As he rotated through various surgical specialties, he was drawn to neurosurgery, which led to his NIH research fellowship and subsequent residency at the Medical College of Virginia (where he also earned a doctorate in anatomy and neurobiology).

Now, at City of Hope, Chen wants to bring his studies to fruition.

“City of Hope is one of the very few places where you can develop something in the lab and bring it into the clinical realm,” he said, noting the institution’s facilities for creating biologic therapies. “You can get things done quickly. If you make a novel discovery here, it’s feasible you can also examine its clinical efficacy here. And that’s exciting.”