Dr. Goodman on the Use of SBRT in Locally Advanced Pancreatic Cancer

Karyn A. Goodman, MD, MS, professor and vice chair for Research and Quality in the Department of Radiation Oncology at the Icahn School of Medicine at Mount Sinai, and associate director for Clinical Research at The Tisch Cancer Institute at Mount Sinai, discusses key toxicity and efficacy data supporting the use of stereotactic body radiation therapy (SBRT) in locally advanced pancreatic cancer.

Previous studies have shown that the efficacy of intra-arterial therapy was improved with the administration of prior radiation therapy, Goodman begins. Based on these results, the phase 3 TIGeR-PaC trial (NCT03257033) was designed to evaluate either SBRT or intensity-modulated radiation therapy (IMRT) during the induction phase prior to randomization of intra-arterial chemotherapy with gemcitabine or gemcitabine and nab-paclitaxel (Abraxane) in locally advanced pancreatic cancer, Goodman explains. IMRT was administered to the pancreas as 45 Gy in 25 fractions with concurrent capecitabine (Xeloda), while SBRT was administered as 33 Gy in 5 fractions.

Analysis of efficacy data did not show a statistically significant difference in percent change of tumor size, RECIST partial response rates, and CA 19-9 tumor markers. However, patients in the SBRT subgroup did experience improved tolerance and a better toxicity profile, Goodman notes. These findings suggest that SBRT may be a preferrable option for patients with pancreatic cancer, she says.

In addition to encouraging clinical data, SBRT has several practical advantages, Goodman states. Since SBRT is typically administered as 5 treatments over the span of 2 weeks, it can minimize the duration of hospitalization for patients, she explains. Unlike standard chemoradiation therapy, SBRT also involves focal radiation delivery to primary tumor and adjacent nodes rather than a large field. This targeted delivery produces minimal toxicity and is well tolerated, she concludes.