Radboud university medical center pioneers lung cancer diagnosis with Philips technology for bronchoscopic procedures

Taking a biopsy sample from a small, suspected abnormality in a patient’s lungs via a bronchoscopy can be quite a challenge. During the process, good navigation is indispensable. A recent clinical study from Radboud university medical center (Radboudumc, Nijmegen, The Netherlands) shows promising results using Philips Lung Suite. This solution enables all-in-one lung cancer diagnosis and treatment. It provides advanced real-time 3D imaging with augmented fluoroscopy on the company’s Image Guided Therapy System – Azurion, combined with dedicated software. With Philips’ Cone Beam CT imaging, the X-ray detector rotates around the patient to generate a CT-like image in around 5 seconds, providing clinicians with a high-resolution 3D view of the target lesion and other anatomical structures. This allows the clinician performing the biopsy procedure to be continually guided by high-quality real-time imaging to advance a catheter towards the lesion through a bronchoscope. Once done, its position can be confirmed in real-time using the same imaging modality and a biopsy sample removed.

Clinical study results

The results of the clinical study by Radboudumc were published in the October 2021 issue of the Journal of Bronchology & Interventional Pulmonology: Volume 28 - Issue 4 [1].

Dr. Erik van der Heijden, Pulmonologist and Associate Professor of Interventional Pulmonary Diseases at Radboudumc, led the study: “Initially, we were at a diagnostic accuracy of 72%. By the end, we were able to perform a biopsy using navigation in almost 100% of cases, and in 90% we had enough tissue for the pathologist to make a diagnosis. The average total effective radiation dose per procedure was reduced by more than half, including an effective fluoroscopy radiation dose reduction from 5.2 mSv to 0.37 mSv.”

“My focus is on detecting lung cancer at an early stage. A tumor in the lungs is now often discovered by chance, because a CT scan is performed for a reason other than lung complaints and a suspicious spot is then found in the lungs by chance. From such a suspicious abnormality, you would then like to obtain tissue in a safe manner that a pathologist can use to make a diagnosis.”

3D visualization

The airways and lungs are not the easiest places to biopsy. “We need good navigation to make sure we're in the right spot,” says Dr. Heijden. “You can use electromagnetic navigation for bronchoscopy or you can use cone-beam CT, which allows you to create 3D visualizations using an X-ray scanner that rotates around the patient's body. You can then follow the correct path from different angles to where you need to be, which is particularly useful for very small abnormalities.”

“An initial reaction you often hear to the application of X-ray for these kinds of procedures is that you shouldn't want to use it because of the radiation. So we started researching ways to use CBCT technology, in this case Philips Lung Suite, to increase the accuracy of diagnosis while reducing the radiation dose.”

A steep learning curve

“You could say we have had a very steep learning curve,” comments Dr. Heijden. “That was due to a number of factors, but the 3D imaging capabilities of the cone-beam CT scanner helped to continually evaluate and perfect the navigation procedure. And we introduced new protocols, which allowed the search area to be made smaller, which in turn allows for lower radiation into the lungs. We actually started using the Philips Azurion platform more in the way it was made for. For example, we can now image patients with an overlay of augmented fluoroscopy. That took some practice, but in the end the results are great. We are currently the first in the world to have such a high yield with this technology.”

What helped, according to Dr. Heijden, was the collaboration with technical physician Roel Verhoeven. “Our team composition is really great in that respect. It really helps when someone with a solid technical background is on your side,” he says. “Besides that, it was just a matter of persevering, and gaining experience with the use of 3D imaging. Only if you keep innovating as a physician can you make the results for patients better and better.”

Low-threshold collaboration

Dr. Heijden’s team worked closely with Philips in the study. "Because the application of this technology plays such a large role in successfully performing these procedures, it is important that we can spar with the team at Philips in an approachable way. Among other things, they helped us increase the accuracy and safety of the procedure by making the imaging more specific to the different requirements and phases of the procedure.”

In the future, Dr. Heijden hopes to increase the use of navigation technology to treat patients with lung cancer. “Patients sometimes say “if you're in the lungs during such a biopsy anyway, just get it [the lesion] out right away”. In the future, that will become possible using microwave ablation, where you can focus microwaves directly into the tumor. We haven't got that far yet, but it could be a very good alternative to radiation and chemotherapy. Then it does help if you can see very well, in real time, where you are in the lung using 3D imaging.”

[1] Journal of Bronchology & Interventional Pulmonology: October 2021 - Volume 28 - Issue 4 - p 262-271 doi: 10.1097/LBR.0000000000000783