‘The future of cancer therapy’: An innovative treatment performed at St. Michael’s Hospital for the first time

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Dr. Andrew Brown looks intently at the screen while performing Dave McManus’ radioembolization treatment.

Guided by expert hands, the wire moves through the patient’s blood vessels inch-by-inch. The physician’s eyes follow its procession on the screen in front of him as he gently works the wire forward. Activity in the room is hushed; the only consistent sound is the repeated ‘beep-beep-beep’ of the monitoring system as it announces the patient’s steady pulse. 

Once in place, the wire will be used to insert a tiny tube – called a micro-catheter – as close as possible to a cancerous tumour located in the patient’s liver. The micro-catheter will then deliver a precision dose of radiation to destroy that tumour. The treatment is called radioembolization and this is the first time it’s being performed at St. Michael’s Hospital. 

Getting the wire to its destination is like navigating a maze. The images on the screen are X-rays taken in real-time that act as a map. Though Dr. Andrew Brown – who is performing the radioembolization – knows where the wire needs to go, getting it there is still a delicate process with many opportunities for wrong turns and setbacks.

The natural flow of blood through the vessels can easily carry the wire in the wrong direction. Blood vessels branch off from one another like the root system of a tree, getting narrower and narrower. Positioning the wire in the right branch can take anywhere from two to four hours.

The reward for reaching the target is well worth the effort: an opportunity to cure the patient – Dave McManus – of cancer. 

Born and raised in Toronto, McManus worked most of his career as a Fedex delivery person. Now six years into retirement, family and music figure most prominently in his life. He lives with his wife, Cathy, in the Junction neighbourhood and they have an adult daughter named Sarah. He also plays bass guitar in blues bands around town a couple of nights a week. 

McManus has experienced cancer once before. The first time, he received surgical treatment at St. Joseph’s Health Centre, a site of Unity Health Toronto. This time, his oncologist discovered a tumour in his liver when he received a CT scan as part of an annual check-up. 

When he first learned about the liver tumour he had a sense of resolve. 

“I’d been through cancer once already and through good fortune and good management, I came through okay,” says McManus. “So I thought, ‘Okay, here we go. We’ll just have to deal with this.’” 

His main focus has been on his loved ones and how they’re coping with his diagnosis. 

“What I’m looking forward to after the treatment is allowing my family some peace of mind because they’re all wrapped up in this whole thing emotionally,” he explains. “If it’s successful, then it will be a good release.”

The care he provides to his patients is personal for Brown. 

He was in the last year of his residency, preparing for exams when he found out that his mother had metastatic gastric cancer, which meant that cancer originating in her stomach had spread to other parts of her body. She received surgery and palliative care at St. Michael’s. 

That experience was Brown’s first time “on the other side of the bed,” as he describes it, and he will always be grateful for the compassion and support that his mother and his family received.

Radioembolization is one example of emerging cancer treatments that provide a more targeted approach than traditional therapies. External beam radiation – the most common form of radiation therapy – focuses beams of radiation at cancerous tumours from outside of the body inward, hitting and hurting any healthy tissue in their path. 

In contrast, radioembolization releases tiny beads that contain a radioactive isotope called Yttrium-90 (or Y-90) to the blood vessels directly surrounding a liver tumour. Radiation from the beads only travels millimeters – directly targeting the cancer.

The side effects are usually minor – especially when you compare them to the weeks of pain and fatigue that can accompany external beam radiation. Patients go home the same day after treatment and might experience nausea or fatigue in the days after. Some will experience an on-and-off fever in the following weeks. 

Radioembolization can only be used to treat certain kinds of liver cancer.

“Patient selection is very important. You really want to be treating people that have cancer confined to one place – in this case, their liver – and who have good liver function,” says Brown. “For folks who are well selected, you’re looking at a significant improvement in their length and quality of life.”

Brown is an interventional radiologist and radioembolization is a form of interventional radiology. Interventional radiologists are physicians who use imaging tools that typically help with making diagnoses – such as ultrasounds, CT scans and X-rays – to provide image-guided, minimally-invasive care that will treat an injury, illness or disease.

McManus is awake and aware for the duration of his procedure, with a local anesthetic to help manage his pain. He’s a model patient, following every request from the care team – to put his hands above his head or hold his breath for the cone beam CT scan – without complaint. Cone beam CT scanners use less radiation and focus on a smaller area than tradition CT scanners.

There are four core members on the care team. Brown is the lead interventional radiologist. Throughout the hours-long procedure – he remains steady and calm. Michele Orridge, a nurse, assists in the procedure and helps to ensure McManus is as comfortable as possible, checking in on him often. 

Heather Armstrong, a medical radiation technologist, operates the imaging devices in the angiography suite – the room where the procedure is taking place – with a confidence that reveals her depth of experience. Dr. Steven Cooper, a physician, assists Brown. This procedure is part of his medical fellowship as he trains in the specialty of interventional radiology. 

At last, a breakthrough. After hours of careful navigation, Brown has placed the micro-catheter for the radiation treatment. The room springs into action.

A call is made to the Nuclear Medicine department to deliver the dose of radiation that has been specially formulated for McManus’ treatment. Nuclear medicine is a medical imaging specialty that uses radioactive materials to diagnose and treat disease. The tiny radioactive beads have been stored in the Nuclear Medicine department with safety protocols in place to prevent a radiation leak. Now similar safety protocols will be enacted in the angiography suite.

The beads arrive in a small, grey, lead-lined canister that is handled with the utmost care. While it looks unassuming, within it lies radiation exposure equivalent to 1.2 million chest X-rays or, in this case, enough radiation to destroy a cancer tumour. 

The care team must follow a methodical process to ensure all of the beads safely reach their target. Special instruments – including tubes, clamps and shields – control the delivery of the beads and protect McManus and the care team from unintended radiation exposure. Every item that comes in contact with the beads must be discarded as potentially radioactive waste. 

After approximately three minutes, Brown has completed administering the full dose of radiation. 

Two months later, McManus returns to St. Michael’s for a follow-up CT imaging appointment. A couple days after, he gets a call from Brown.

“Bright and early at 8 o’clock Dr. Brown called to give me an update. He’s very upbeat,” recounts McManus. “I was very heartened by what Dr. Brown had to say. He’s got a very reassuring manner about him.”

The procedure was a success. 

“There’s a big hole in the tumour, which means the centre is dying. There’s also some inflammation around it, which is exactly what we want to see,” Brown describes the imaging results. “The rest of the liver looks good too, which means we’re moving in the right direction.” 

As with most cancer treatments, McManus will continue to be monitored with imaging scheduled in another three months.

That morning, McManus’ wife and daughter were getting ready for work but hung back at the door with their coats on for the conversation with Brown to finish so they could hear the news. 

“It’s always good to share this kind of news and help patients like Dave,” says Brown. “I’m grateful that our team was able to get this done and excited that others like him will be able to benefit.”

As of right now, St. Michael’s is one of only four hospitals in Ontario that provide this treatment. Across Canada, it’s only offered in a few major centres. Part the motivation for bringing radioembolization to St. Michael’s is to ensure more patients in Ontario will have access. 

“It’s a burgeoning treatment,” explains Brown. “These types of minimally invasive and targeted procedures really are the future of cancer therapy.”

By Robyn Cox