August 11, 2022 by Muriel Sommers
Treating Advanced Pancreas Cancer: Miami Cancer Institute First in World to Deliver Adaptive MR-Guided Radiation Therapy with MRIdian® A3i System
In another notable first for Miami Cancer Institute, a Miami woman is now the first pancreas cancer patient in the world to be treated using an advanced platform for adaptive MR-guided radiotherapy, doctors at the Institute report.
(Watch now: a new technology at Miami Cancer Institute was used for the first time to treat a patient with advanced pancreas cancer. Video by George Carvalho.)
MR (magnetic resonance) imaging is increasingly being used to guide radiation therapy, especially for inoperable or difficult to reach tumors, according to Kathryn Mittauer, Ph.D., the lead physicist for the MR-guided radiation therapy program at Miami Cancer Institute, which is part of Baptist Health. The ViewRay MRIdian® Linac system uniquely shows the patient’s internal anatomy throughout treatment using real-time continuous MR scans and automatically pauses treatment if the tumor moves out of the correct position, explains Dr. Mittauer. These advanced MR capabilities, which are not offered by other radiation delivery machines, can improve the ability to eradicate tumors and decrease the risk of side effects. Miami Cancer Institute has been one of the international pioneers treating patients with the MRIdian Linac since 2018, she adds.
Flash-forward to today and what ViewRay calls its MRIdian A3i upgrade, which gives the MRIdian system a suite of new and enhanced features that provides even greater precision and control, says Dr. Mittauer, who worked closely with ViewRay’s team in California to develop MRIdian’s enhanced capabilities. Miami Cancer Institute recently became the first in the world to use MRIdian A3i for adaptive radiation therapy, an advanced technique by which the delivered radiation is modified each day to ensure that high doses are precisely delivered only to the tumor, even if there are significant changes in the patient’s internal anatomy.
Thanks to MRIdian A3i’s parallel workflow technology, the medical physicist and radiation therapist can now work side by side – literally – with the radiation oncologist to deliver adaptive treatments. “Before, we could only perform our roles one at a time and wait for our colleagues to finish their part before we could step in and do ours,” Dr. Mittauer says. “With MRIdian A3i’s parallel workflow capability, our team can now collaborate far more effectively, with each of us performing our roles simultaneously. We expect that the A3i system will reduce treatment times for some patients by up to 40 top 50 percent, resulting in a remarkably better patient experience.”
Michael Chuong, M.D., who is the lead physician for the MR-guided radiation program and the Medical Director for Miami Cancer Institute’s Department of Radiation Oncology, has been instrumental in helping ViewRay perfect the technology and train other radiation oncologists in its use. He calls the recently released MRIdian A3i “a transformational improvement to an already amazing technology.”
Enhanced imaging one of several key benefits
Another feature of the MRIdian A3i system, according to Dr. Mittauer, is that it offers more extensive and higher quality soft tissue imaging. “The image quality has greatly improved, which enables us to better identify what’s tumor and what’s not,” she says. “This helps us deliver extremely high, or ablative, doses of radiation directly to the tumor with pinpoint accuracy,” she says.
Additionally, Dr. Mittauer says, MRIdian A3i offers multiplanar tracking and automated beam control, which means the tumor can be tracked in three dimensions with any combination of coronal, sagittal or axial planes, and therefore direct the precise radiation delivery much more accurately. This is important, she explains, because it allows for reduced set up margins, or outer edges of the tumor’s computer-mapped treatment area, even further. “This means we can reduce the radiation exposure delivered to patients, and therefore also better spare healthy surrounding tissues and organs,” she adds.
This next-generation technology has special utility in treating soft-tissue tumors in the pelvic, abdominal or thoracic regions that typically are subject to movement from adjacent organs, such as lungs expanding and contracting during respiration, according to Dr. Chuong.
“As a patient breathes, their organs can move a lot – sometimes as much as three to five centimeters – so it’s important for us to be able to see the tumor in real time as it moves and to deliver radiation only when it’s in the correct position,” Dr. Chuong explains, adding that the beam automatically shuts off the instant any part of the tumor shifts outside of the precisely mapped, clinician-defined treatment boundaries, and then the treatment automatically resumes when the tumor returns to the correct position.
Treatment with the MRIdian Linac is uniquely interactive for patients who, while lying in the machine, are able to view their scan in progress through a special mirror. The tumor’s outline can be seen by the patient on a screen as a green circle, which moves in real-time during respiration. When the patient breathes in such a way that the green circle overlaps a stationary purple circle defining the target treatment area, the treatment starts and a yellow happy face appears indicating the patient should hold their breath at that exact position. This ensures that treatment is delivered to the tumor only and not nearby organs.
“By helping the patient control their breathing and guide their own treatment, this visual feedback makes it easier to deliver radiation and helps reduce overall treatment time,” Dr. Chuong says. “For the patient, that means less time having to lie perfectly still inside the MRI, which for some people can be difficult or stressful.”
Her UTI leads to surprise diagnosis
Daniella Fassioli, a 52-year-old assistant store manager for Pink, received her cancer diagnosis last November. She had been feeling terrible because of a urinary tract infection (UTI) and went to the emergency department at Baptist Hospital for treatment. The attending physician reviewed her imaging and alerted her to what he thought was a tumor on her pancreas. He told her he wanted to admit her for further tests.
Ms. Fassioli was shocked. “I had no symptoms whatsoever. The only reason I went to the ER was because of my UTI,” she says. “I didn’t expect to be diagnosed with cancer. And I didn’t even know where the pancreas was exactly or what it does.” After a biopsy revealed that she did indeed have pancreas cancer, she was referred to Horacio Asbun, M.D., a surgical oncologist at Miami Cancer Institute who specializes in treating cancers and diseases of the liver, gallbladder, biliary system and pancreas. After reviewing her case in detail, he felt that she was not a candidate for surgery because of the locally extensive nature of her tumor involving nearby blood vessels.
Dr. Asbun discussed Ms. Fassioli’s case with other pancreas cancer experts at the Miami Cancer Institute multi-disciplinary pancreas tumor board. There was consensus that she should first receive chemotherapy in an attempt to shrink her tumor so that she might later be a surgical candidate. She completed 14 cycles of chemotherapy overseen by Fernando De Zarraga, M.D., a medical oncologist who specializes in treating pancreas cancer. “I didn’t know what to expect with chemotherapy, but it wasn’t a bad experience at all,” Ms. Fassioli says. “Yes, my hair started falling out and I felt tired and nauseous at times, but overall, it went very smoothly.”
Fortunately, Ms. Fassioli responded to chemotherapy, although her tumor still was not operable. She was then referred to Dr. Chuong, considered one of the world’s foremost authorities on MRI-guided radiation therapy and the radiation oncologist who pioneered use of the MRIdian Linac at Miami Cancer Institute. He explained that high dose radiation therapy targeted precisely at her tumor could increase the probability of her having surgery. When considering the specifics of her case and the many state-of-the-art radiation technologies offered at Miami Cancer Institute, including proton therapy and CyberKnife, Dr. Chuong recommended the MRIdian Linac because of its advanced imaging and adaptive delivery features.
Three-dimensional imaging offers unprecedented accuracy
“The ablative radiation doses we’ve delivered to pancreas cancer patients on our MRIdian Linac have been associated with long-term survival outcomes not before thought possible,” Dr. Chuong says. The radiation dose that can be safely delivered with the MRIdian Linac is considerably higher than with other advanced radiation machines because of its advanced imaging and targeting capabilities. “With the A3i upgrade, we are now able to continuously visualize the tumor with MRI from many directions simultaneously throughout treatment,” Dr. Chuong continues. “This gives us an unprecedented ability to be certain that high dose radiation is delivered only to the tumor and not to other nearby organs.”
This translates to fewer side effects for the patient, says Dr. Chuong, and compresses total treatment time, reducing the number of outpatient treatment sessions for many patients to no more than five, compared to the 28 typically required for lower-dose forms of radiation therapy. Some patients may be eligible for ablative radiation therapy with the MRIdian Linac in only one outpatient session.
“Being able to eradicate tumors with minimal or no toxicity is important, of course, but decreasing the amount of time they spend here and the number of treatments they need is critical to preserving and improving their quality of life,” says Dr. Chuong. “The sooner they can complete their treatment, the sooner they can get back to their family, their work and their routine.” Also, because treatment with the MRIdian Linac is completely non-invasive and is done without anesthesia patients have essentially no downtime.
Ms. Fassioli had the first of five treatments on the MRIdian A3i on July 5th and her final treatment was July 11th. She feels fortunate to have been able to take advantage of the new technology. “To be the first pancreas cancer patient in the world to be treated with this, I am very blessed and thankful for that,” she says. “The doctor recommended that I rest, but I feel great and have no side effects whatsoever. I even went to work after my treatments.”
New hope for treating advanced pancreas cancer
Pancreas cancer has long had a reputation as one of the most elusive and difficult-to-treat cancers because it can go undetected – sometimes for years – until it has spread elsewhere in the body. Until recently, there were few, if any, effective treatment options, which is why the prognosis is typically poor for many patients diagnosed with advanced disease. According to the American Cancer Society, pancreas cancer has a mortality rate of roughly 80 percent and is the fourth leading cause of cancer deaths among both men and women in the U.S.
Patients diagnosed with inoperable pancreatic cancer have especially poor prognoses, Dr. Chuong says, but that has changed with the advent of MR-guided radiation therapy, which he says offers new hope for these patients and significantly increases average survival time. “We have published the largest experience of ablative radiation therapy using the MRIdian Linac for inoperable pancreas cancer that shows long-term survival might be doubled compared to what is expected with conventional lower dose radiation therapy,” he says. “That is incredibly exciting for patients and their families.”
Dr. Chuong says Miami Cancer Institute and specifically its MRIdian program is one of the most experienced in the world in treating patients with MR-guided radiotherapy. “We’re one of the highest-volume cancer centers in the world to be using this highly advanced technology,” he says. Patients from across the United States and beyond routinely travel to Miami Cancer Institute to be treated with the MRIdian Linac, especially because of the Institute’s renowned expertise with the technology.
Dr. Chuong and Dr. Mittauer are principal investigators for several national and international clinical trials – several of them underway now at Miami Cancer Institute – that are assessing the efficacy of MR-guided radiotherapy in treating various cancers, including pancreas cancer. Dr. Chuong says he hopes their findings will contribute to changing the paradigm of how inoperable cancers are viewed, and the different treatment options that are offered to those patients.
“It’s always difficult to be diagnosed with cancer – especially pancreas cancer,” Dr. Chuong acknowledges. “But I think we’re giving patients real hope that that there is a chance for substantially longer survival while maintaining or even improving their quality of life.”
There’s always hope that something can be done
As for Ms. Fassioli, she’ll be following up with her multi-disciplinary pancreas cancer team regularly and a determination will be made later this summer as to if and when she should have surgery. In the meantime, she says she is just taking one day at a time. She says that Miami Cancer Institute is the best thing ever happened to her, and that she’s confident her cancer journey will be successful.
“I’m not just saying it,” says Ms. Fassioli, who describes herself as a “very strong, very positive” woman. “I feel it and I can visualize it. I’m blessed to have the experts working with me and Dr. Chuong is just amazing. I’m very happy he’s my doctor. I truly believe that I’m in the hands of the best of the best.”
Ms. Fassioli says that she felt something special the minute she walked into Miami Cancer Institute for the first-time last November. “From that moment on, I felt like everyone knows me and that they are here just for me,” she says. “The nurses are so amazing and so caring, and everyone is so professional. This is the best place to come for cancer treatment. I know I’m in the right hands here. I’m very blessed.”
Ms. Fassioli says she hopes her experience provides hope to others who get a diagnosis of cancer. “It’s okay to feel sad and overwhelmed, but be positive and listen to your doctor,” she advises. “And don’t lose hope – there’s always hope that something that can be done.”