Precision Radiation Cuts 1-Year Pancreatic Cancer Recurrence to 20.2%

A short course of high-dose, targeted radiation added to chemotherapy lowered the chance that pancreatic cancer came back in or near the pancreas within a year, according to results of the phase 2 MASTERPLAN trial published Oct. 23 in The Lancet Oncology. The trial, run by the Australasian Gastro-Intestinal Trials Group, enrolled patients with high-risk pancreatic cancer that had not spread to distant organs.

At 12 months, cancer had returned in or near the pancreas, known as locoregional recurrence, in 20.2% of patients who received chemotherapy plus stereotactic body radiotherapy (SBRT), compared with 52.0% of those who received chemotherapy alone. The trial met its primary end point of 12-month locoregional recurrence.

SBRT "warrants further investigation in larger studies," the researchers wrote.

What did the MASTERPLAN trial find about pancreatic cancer recurrence?

The addition of SBRT reduced the risk of locoregional recurrence by 56% compared with chemotherapy alone.

Patients were followed for a median of 3.2 years. The researchers also reported longer progression-free survival, or the length of time patients lived without their cancer growing or spreading, in the SBRT group.

Who was in the phase 2 MASTERPLAN trial?

The trial included 74 patients with high-risk pancreatic cancer at 14 hospitals in Australia and New Zealand. High risk included tumors larger than 4 centimeters, cancer that had grown beyond the pancreas or into nearby lymph nodes, borderline resectable cancer that might be removable after treatment shrinks it and locally advanced cancer that usually cannot be removed with surgery because it involves nearby blood vessels.

Patients were randomly assigned in a 2-to-1 ratio to chemotherapy plus SBRT (49 patients) or chemotherapy alone (25 patients). Both groups first received 12 weeks of chemotherapy chosen by their doctor, either modified FOLFIRINOX, a combination of four chemotherapy drugs, or gemcitabine plus Abraxane (nab-paclitaxel). Patients in the SBRT group then received 40 Gy of radiation over five sessions, given two to four times a week. Afterward, each patient was assessed for surgery. Those who had surgery received another 12 weeks of chemotherapy, and those who could not have surgery continued chemotherapy for another 12 weeks.

Patients enrolled between Feb. 26, 2020, and Jan. 6, 2025. The trial planned to enroll 120 patients but closed early because of slow recruitment.

What side effects did patients have with SBRT for pancreatic cancer?

Serious side effects (grade 3 or higher) occurred in 70% of patients who received chemotherapy plus SBRT and 64% of those who received chemotherapy alone, a difference that could have come about by chance.

The most common serious side effects were diarrhea, which occurred in 15% of patients in the SBRT group and 20% of those in the chemotherapy-alone group, and blood clots (6% and 4%, respectively). One patient in the chemotherapy-alone group died from a bile duct infection related to treatment.

Two serious side effects were linked to SBRT, a small bowel obstruction (a blockage in the intestine) and pancreatitis (inflammation of the pancreas).

Each patient's radiation was checked through a real-time quality review as part of the trial.

What do the MASTERPLAN results mean for patients with pancreatic cancer?

The results suggest that SBRT may help keep pancreatic cancer from returning near its original site in patients whose disease has not spread to distant organs. Because the trial was small and closed early, larger studies will need to confirm whether the approach helps patients live longer.

Patients with high-risk pancreatic cancer can ask their care team whether radiation is part of their treatment plan, or whether a clinical trial testing SBRT is available.

References

1. Oar A, et al. "Perioperative chemotherapy and stereotactic body radiotherapy versus perioperative chemotherapy alone in patients with high-risk, localised pancreatic cancer (MASTERPLAN): an open-label, phase 2, multicentre, randomised trial of the Australasian Gastro-Intestinal Trials Group." The Lancet Oncology. Published Oct. 23, 2026.

For more news on cancer updates, research and education, don't forget to subscribe to CURE®'s newsletters here.