Electromagnetic waves make quick work of man’s kidney lesion

November 15, 2016 GMT

A quick surgery to blast a potentially cancerous lump on Kenny Nagel’s left kidney last week had him on the operating table for only an hour and may have been the first procedure of its kind in the state.

Nagel underwent a renal microwave ablation, a minimally invasive procedure in which doctors use electromagnetic waves to heat a small area to the point that it kills tissue and prevents cell growth, on Thursday at St. Vincent Healthcare.

“This is actually really cool,” he said a few minutes before the procedure. “It’s not as big a deal for me, but it is a big deal that this is the first in Montana, that it’s here for people.”


Hospital officials said that, to the best of their knowledge, it was the first time microwave ablation was used on a renal tumor in Montana, but it’s something they expect to see more of soon.

Dr. Brian Christenson, the St. Vincent interventional radiologist who performed the surgery, said he’s been performing similar surgeries — using heat and another called cryoablation that freezes tissue — for more than a year at the hospital.

“We use it to treat lesions that are fairly small, five centimeters or less, usually,” he said. “And it’s been effective. Patients had a survival rate of about 95 percent after five years. It’s usually offered as an alternative for people who want a less-invasive procedure.”

For Nagel, a water jet operator at Synthesis Industries in Lewistown, the surgery takes care of a serious issue — a lesion, or abnormality, that could potentially be cancerous tumor — using high-tech methods close to home.

Earlier this fall, he felt a pain in his side and set up an appointment with his primary physician in Lewistown. A CT scan revealed the small lesion, about 2.5 cm in diameter, on his left kidney and, since staff there didn’t feel comfortable operating on it, they set up with a specialist, who connected him with Christenson in Billings.

“They brought this up as an option and I really liked the idea,” Nagel said. “To be honest, I was scared. The one thing that really helps me out is the trust that I have in Dr. Christenson and his staff. Now I’m more scared of the not knowing. We don’t know if it’s cancerous.”

Christenson said that in most cases, he’ll take a biopsy of the tissue to confirm whether or not its cancerous. About three-quarters of the time, the results indicate a small cancer, he said.

A microwave ablation patient is typically on the table for about an hour from start to finish, with the procedure lasting only five to 10 minutes, and is usually awake under conscious sedation the entire time. Cryoablations take a bit longer, with the procedure lasting about 45 minutes and a patient on the table for several hours.


The procedure itself involves inserting one or two small, needle-like tubes — guided using real-time images from an ultrasound, a CT scan or both — into the the area with the possible tumor, which then heat up the desired area to kill the tissue.

“Some people describe it as like a little smart bomb,” Christenson said. “You get in there and it spreads a little and it kills the tumor.”

In some cases, such as Nagel’s, where other organs, tissue or other structures are close by, doctors can also inject a layer of saline solution to provide a buffer and protect those areas from being damaged by the extreme temperatures.

The procedure has been gaining wider use in the last five to eight years and is used at St. Vincent to treat potential small cancers on the liver, kidneys and lungs, although it is also used elsewhere on other soft tissue and even bone.

After Nagel’s surgery, during which he was awake and speaking with medical staff and was even allowed to wear his University of Montana Grizzlies baseball cap, he spent a night at the hospital for observation before heading home with his wife, Heidi.

“I’m really happy about everybody being so optimistic,” she said. “That really helps.”

Medical staff also took a biopsy of the tissue, which will be tested. Results on whether or not its cancerous will be available in a week or so and Nagel will return quarterly for checkups and, if necessary, further treatment.

The procedure used to be mostly for people who weren’t good candidates for a traditional surgery, such as a nephrectomy, to remove tissue but that it is now being used in more and more cases. In addition, St. Vincent is now in the process of “letting more people know we do this,” Christenson said.

It isn’t available to everybody, but for those with one or two lesions and with not signs of spreading it could be an option.

For those patients, including Nagel, it can provide not only peace of mind, but also the convenience of new treatments close to home.

“It’s not just helping Billings, it’s the surrounding areas too,” he said. “It’s Lewistown, these little towns all over the place, and they don’t have to go very far. This is here now. You don’t have to go to Denver or Seattle for it. That makes you feel comfortable.”