Laser targets pancreatic tumors by homing in on collagen

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, utilizes the tumor’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 fibers than healthy pancreatic cancer, using a mid-infrared laser at a wavelength strongly absorbed by collagen fibers can ablate the cancerous tissue while preserving the healthy pancreas.”

In their paper published in Optica, the researchers describe the new method, which is based on a high-power femtosecond mid-infrared laser they developed. Using PDAC tumors 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 tumors rich in specific biomolecules that opens a new pathway for future minimally invasive and precision oncology treatments.”

Leaving healthy tissue intact

Tumor 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 tumor. 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 tumor 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 tumor’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 fiber.

With an outer diameter of less than 400 microns and bending losses below 1 dB/m at radii under 10 cm, the hollow-core fiber 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 minimizing 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 tumors versus normal pancreatic tissue.

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

Targeting collagen-rich tumors

“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 optimize 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 tumor types with different molecular signatures.

The researchers point out that a great deal of work is needed before the method can 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 fiber delivery system to ensure ease and safety in clinical settings.