Researchers have developed a new laser-based technique that targets pancreatic ductal adenocarcinoma (PDAC) while leaving healthy tissue intact.

PDAC is the most common type of pancreatic cancer and the third leading cause of death related to cancer.

“Our technology, for the first time, utilises the tumour’s molecular fingerprint to achieve selective ablation,” said research team leader Houkun Liang from Sichuan University in China.

“We found that because PDAC contains substantially more collagen fibres than healthy pancreatic cancer, using a mid-infrared laser at a wavelength strongly absorbed by collagen fibres can ablate the cancerous tissue while preserving the healthy pancreas.”

In Optica, Optica Publishing Group’s journal for high-impact research, the researchers describe the new method, which is based on a high-power femtosecond mid-infrared laser they developed.

Using PDAC tumours removed from 13 patients, they showed that the new approach was two to three times more efficient at destroying cancerous tissue compared to healthy pancreatic tissue.

 “Our work could lead to a new minimally invasive strategy for efficiently ablating PDAC while saving the healthy pancreas,” said Liang.

“This could largely reduce surgical complications, preserve normal organ function and, more importantly, provide a reference for treating other tumours rich in specific biomolecules that opens a new pathway for future minimally invasive and precision oncology treatments.”

Leaving healthy tissue intact

Tumour ablation is a minimally invasive treatment that destroys cancerous tissue without surgically removing it by applying laser light, thermal energy or a chemical agent directly to the tumour.

Although various ablation techniques have gained increasing clinical attention for treating pancreatic and other cancers, they have not yet been widely implemented in clinical practice due to concerns about injury to healthy tissue.

“Our broader project aims to develop a laser-based surgical platform that uses molecular fingerprints to reduce collateral damage and guide selective ablation,” said Liang.

“There is an urgent clinical need for safer and more precise treatment options for various cancers and tumour types, eye diseases and atherosclerosis, and this can be accomplished by using a laser wavelength that precisely matches specific biomolecular absorption features.”

To develop a treatment tailored for pancreatic cancer, the researchers first identified the laser wavelength most strongly absorbed by the tumour’s abundant collagen molecules—6.1 microns.

Liang’s team collaborated with Wonkeun Chang’s team at Nanyang Technological University in Singapore, which developed a new anti-resonant hollow-core fibre.

With an outer diameter of less than 400 microns and bending losses below 1 dB/m at radii under 10 cm, the hollow-core fibre enables reliable delivery of laser light deep inside the human body.

For enhanced clinical use, it can be equipped with a biocompatible medical-grade polyimide jacket and sapphire endcaps, ensuring durability and minimising the risk of breakage inside the body.

After establishing that the 6.1‑micron laser wavelength interacts safely and predictably with tissue, the researchers tested the selective ablation of surgically removed human pancreatic ductal adenocarcinoma tumours versus normal pancreatic tissue.

They found that the 6.1-micron wavelength enabled high selectivity for pancreatic tumour tissue, which minimises damage to normal tissue, while also improving ablation efficiency compared to non-resonant wavelengths like 1 or 3 microns.

Targeting collagen-rich tumours

“This method is particularly suited for pancreatic ductal adenocarcinomas with high collagen content that are accessible to laser delivery,” said Liang.

“Clinically, the laser light could be applied during a minimally invasive surgery or endoscopic procedure.

The researchers are now working to optimise the laser parameters and delivery systems to further improve ablation efficiency and system stability.

They are also integrating optical coherent tomography into the system with the aim of performing cancer examination and ablation simultaneously.

Additionally, they want to explore the applicability of this technology to other tumour types with different molecular signatures.

The researchers point out that a great deal of work is needed before the method could be routinely used in the clinic.

This includes comprehensive biological safety assessments and structured clinical trials that assess efficacy and risks.

They also plan to refine the integration of the laser source and fibre delivery system to ensure ease and safety in clinical settings.

Source: Optica