Lasers are used in a variety of medical treatments. Catheters have long been used to deliver treatments within the body. And MRI machines are a common tool for diagnostic imaging. Now a Plymouth-based company is pioneering the use of all those technologies in concert to treat brain cancer.

Notoriously difficult to treat, brain tumors often require a portion of the patient's skull to be removed. But even then, some tumors are positioned in such a way that access is restricted or impossible.

Monteris Medical's NeuroBlate System allows a neurosurgeon to precisely guide a laser-tipped catheter directly into a tumor and then kill only the diseased tissue. All the while the patient lies in an MRI machine. The procedure is minimally invasive, and patients can be on their feet within hours and sent home within a couple of days. They also can receive follow-up radiation and chemotherapy treatments much faster than if they received traditional surgery.

The key to this system is the company's proprietary software that allows the surgeon to use the MRI machine to visualize the tumors in three dimensions and then control the catheter to destroy cancerous lesions right to the boundary of healthy tissue. The technology helps prevent damage to vitally important tissue that may surround a tumor.

The company received a $7.8 million round of venture capital financing in January and $9 million in May 2012. So far, the company has raised $48 million to develop and commercialize the system.

Monteris is owned by Canadian and U.S. venture capital funds and has offices in Plymouth and Winnipeg. John Schellhorn was named CEO in April 2012. Schellhorn is a veteran of a variety of medical device companies, most recently as the chief commercialization officer of California-based BÂRRX Medical until it was acquired by the global health care company Covidien in January 2012. He's also worked at Soft­scope Medical Technologies Inc., EV3 Inc., ACMI Corp. and Boston Scientific.

Schellhorn moved Monteris Medical's headquarters to Plymouth in September. "We choose to move here because we felt it was the best place to scale up the company," Schellhorn said.

The company was founded in 1999, but it wasn't until 2009 that its system was first used in a human. The company moved from the development stage to the commercial stage with the sale of its first system in 2011.

"We currently have seven installations," Schellhorn said. "And they are all at leading academic institutions in the country." The system is in place at five institutions in the United States, including the Cleveland Clinic and Yale University, one in Canada and a sixth site in the U.S. is planned.

The company also has reached a milestone in its commercialization phase after it recently treated its 100th patient.

According to Schellhorn, 30,000 patients a year in the United States are diagnosed with primary brain tumors and another 270,000 patients with metastatic tumors — ones that spread from other parts of the body. But there are a large number of patients who can't get standard surgical therapy for either primary or metastatic tumors. Schellhorn believes that many of these patients can be served by the NeuroBlate System.

"We think the opportunity in the U.S. alone is a $1 billion market opportunity potentially," Schellhorn said. "The vast majority of brain tumor patients exist outside the U.S."

Schellhorn and Monteris Medical have a third generation of the system under review with the Food and Drug Administration and expect approval of the new system in the first half of 2013.

"Our 510k clearance is for ablation of brain lesions — coagulation of brain lesions — and of course cancer can be considered a brain lesion, as is epilepsy."

The company has been focusing on the brain-tumor market but customers have let them know this procedure is adaptable to epilepsy procedures. Monteris is studying the epilepsy market.

"The technology is flexible enough that we can be used in those procedures," Schellhorn said.

Dr. Greg Foltz, a director of the Ivy Center at the Swedish Neuroscience Institute in Seattle, is a neurosurgeon who has performed more than 300 brain-cancer surgeries a year. Although he has not used the NeuroBlate System, he said the fact that the procedure has been used on approximately 100 patients is significant.

"This is definitely a point where we can use this technology to help patients," Foltz said. "This is unique and they have done a good job of bringing all the technologies together and getting the necessary approvals."

Dr. John Henson is medical director of the Ivy Center and a fellow at the American Academy of Neurology. He says that there have been a number of treatment advances over the years but in general there are three principal components to treat brain cancer: surgery, radiation and chemotherapy.

The treatment of brain cancer depends on many variables and Monteris' Schellhorn acknowledges that there will never be just one therapy for treating the disease.

Patrick Kennedy • 612-673-7926