UCI Health trials laser therapy to shrink inoperable pancreatic tumors before surgery

At the UCI Health Chao Family Comprehensive Cancer Center in Orange County, California, a small group of pancreatic cancer patients are undergoing a treatment that, until recently, did not exist. The procedure is called vascular targeted photodynamic therapy, or VTP—a technique that uses a light-activated drug and a laser to shrink tumors that have wrapped themselves around the major arteries of the abdomen, making conventional surgery impossible.

Pancreatic cancer is among the deadliest of all malignancies, and the reason is structural: even when the disease remains localized to the pancreas and has not spread elsewhere, about two-thirds of those patients cannot be operated on. Their tumors have grown into the blood vessels that feed the abdominal organs. Removing the cancer would mean removing the vessels, which would kill the patient. So they face the same grim prognosis as those whose cancer has already metastasized—a death sentence dressed up as a localized problem.

UCI Health is one of only two cancer centers in the United States testing whether VTP can change that calculus. The approach was developed by ImPact Biotech, an Israeli biotechnology company, and the lead investigator here is Dr. Nadine Abi-Jaoudeh, a radiologist and nationally recognized expert in interventional cancer treatment. The method is straightforward in concept, though intricate in execution. Doctors inject patients with padeliporfin, a drug that becomes active only when exposed to specific wavelengths of light. They then thread a balloon catheter into the tumor-encased blood vessel. Inside the balloon sits a laser. When activated, the laser illuminates the drug, triggering a photochemical reaction that destroys the tumor's blood supply network and, ultimately, the tumor itself.

The treatment happens in two five-minute sessions. Tissue begins breaking down immediately, but the surgical team waits two weeks before removing what remains. There is a cost: patients must spend three days in complete darkness. Light exposure after treatment can damage healthy tissue elsewhere in the body—skin, eyes, organs—which is why VTP has not been used on larger tumors or broader areas. It is a therapy built for precision, for the specific problem of a tumor strangling a critical vessel.

Six patients have enrolled in this phase 1 trial so far. Three were treated initially, and their results were published in the Journal of Vascular and Interventional Radiology. Three more have since received the therapy. Of the six total, four went on to have surgery to remove the remaining tumor tissue. Three of those four patients showed no evidence of cancer cells at the surgical margins—meaning the laser therapy had done its job so thoroughly that when surgeons cut out what was left, they found only dead tissue and clean edges.

It is a small number, but in the context of pancreatic cancer, it is significant. These were patients who had no surgical option before. Now, after VTP, they could be operated on. Now, three of them may have a genuine chance at being cancer-free. The trial is testing three different doses of laser illumination to determine which is most effective. If the early promise holds, the FDA will approve phases 2 and 3, which will expand the study to larger patient populations to confirm whether this approach can be reliably replicated and scaled. For now, the work continues in the dark room, where light itself becomes the weapon.