Reaching the unreachable: New technique opens route to deep lung tumors

Osaka, Japan - Researchers at The University of Osaka have engineered a novel technique, Balloon-Assisted Bronchoscope Delivery (BDBD), to guide endoscopes to small, early-stage lung cancers hidden deep within the periphery of the lungs. By using a small balloon to gently widen the airways, this innovative method overcomes the physical limitations of conventional bronchoscopy, promising to revolutionize both the accuracy of early diagnosis and the potential for minimally invasive treatment.

Lung cancer is a leading cause of cancer mortality worldwide. While CT scans have improved the detection of small, suspicious lesions in the peripheral lung fields, obtaining a definitive diagnosis requires a tissue biopsy. However, the bronchi—the airways of the lung—become progressively narrower and more complex toward the periphery, making it physically impossible for conventional bronchoscopes to reach these remote targets. Clinicians were often forced to stop several centimeters away, limiting the precision of biopsies and subsequent treatment.

Instead of pursuing thinner endoscopes, the research team adopted a paradigm-shifting approach: widening the airway to create a path. The BDBD method involves advancing a thin catheter with a small balloon to the point where the bronchial pathway narrows. The balloon is gently inflated, dilating the bronchus and allowing the bronchoscope to be advanced further toward the lesion. In a first-in-human clinical trial, the team successfully demonstrated that this technique is both safe and effective, enabling access to lesions smaller than 20 mm.

The BDBD technique offers a major breakthrough by enabling access to the peripheral lung field with minimal burden on the patient through the use of a simple balloon catheter. This enhanced accessibility is expected to dramatically improve the diagnostic accuracy for early-stage lung cancer, allowing for earlier and more effective intervention. Furthermore, it paves the way for future endoscopic therapies, where tumors can be treated in a minimally invasive manner without the need for major surgery.

"BDBD is a homegrown Japanese technology developed through industry-academia collaboration," says Professor Atsushi Kumanogoh. "Our study has demonstrated its utility and safety. By allowing us to reach deep into the lungs where we couldn't before, we expect to significantly expand the options for early diagnosis and minimally invasive treatment of lung cancer."

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The article, “Balloon dilatation for bronchoscope delivery: First-in-human trial of a novel technique for peripheral lung field access,” will be published in Thorax at DOI:  http://dx.doi.org/10.1136/thorax-2025-223218

About The University of Osaka

The University of Osaka was founded in 1931 as one of the seven imperial universities of Japan and is now one of Japan's leading comprehensive universities with a broad disciplinary spectrum. This strength is coupled with a singular drive for innovation that extends throughout the scientific process, from fundamental research to the creation of applied technology with positive economic impacts. Its commitment to innovation has been recognized in Japan and around the world. Now, The University of Osaka is leveraging its role as a Designated National University Corporation selected by the Ministry of Education, Culture, Sports, Science and Technology to contribute to innovation for human welfare, sustainable development of society, and social transformation.

Website: https://resou.osaka-u.ac.jp/en