Top Line: Is there a role for radiation in borderline resectable and locally advanced pancreatic cancer?
The Study: Here is a look back at 18 consecutive patients receiving up front chemo followed by stereotactic body radiation (SBRT) at Cedars-Sinai for borderline resectable (n=12) or locally-advanced (n=6) pancreatic cancer. Chemo typically spanned 6 months from before SBRT to after surgery and was FOLFIRINOX (n=12) or gem/abraxane (n=6). Patients without evidence of progression proceeded to SBRT 33 Gy in 5 fractions to gross tumor (with fiducials) and direct planning target volume (PTV) expansion of 3 mm cropped from adjacent gastrointestinal structures. Four patients also received simultaneous 25 Gy in 5 fractions to adjacent regional nodes. Here 17 of 18 patients (94%) achieved an R0 resection. Median overall survival was 42 months and progression free survival 23 months. At a median follow-up of 30 months, 11 recurrences were observed all with distant disease, and five of these had local progression as well. These outcomes are promising, but the elephant in the room is how to reconcile this with the ALLIANCE trial, an actual prospective randomized trial that indicated no benefit with the addition of SBRT to mFOLFIRINOX. To this the authors bring up a couple of criticisms of the ALLIANCE trial including the unusually high rate of progression prior to radiation in the radiation arm as well as questioning whether the radiation was too conformal and instead would have been better delivered with controlled dose fall off to include regional nodes.
TBL: “Moving forward, it is important that standard target definitions be utilized in ongoing clinical trials evaluating the role of SBRT in pancreatic cancer.” | Chung, Adv Radiat Oncol 2024
The Study: Here is a look back at 18 consecutive patients receiving up front chemo followed by stereotactic body radiation (SBRT) at Cedars-Sinai for borderline resectable (n=12) or locally-advanced (n=6) pancreatic cancer. Chemo typically spanned 6 months from before SBRT to after surgery and was FOLFIRINOX (n=12) or gem/abraxane (n=6). Patients without evidence of progression proceeded to SBRT 33 Gy in 5 fractions to gross tumor (with fiducials) and direct planning target volume (PTV) expansion of 3 mm cropped from adjacent gastrointestinal structures. Four patients also received simultaneous 25 Gy in 5 fractions to adjacent regional nodes. Here 17 of 18 patients (94%) achieved an R0 resection. Median overall survival was 42 months and progression free survival 23 months. At a median follow-up of 30 months, 11 recurrences were observed all with distant disease, and five of these had local progression as well. These outcomes are promising, but the elephant in the room is how to reconcile this with the ALLIANCE trial, an actual prospective randomized trial that indicated no benefit with the addition of SBRT to mFOLFIRINOX. To this the authors bring up a couple of criticisms of the ALLIANCE trial including the unusually high rate of progression prior to radiation in the radiation arm as well as questioning whether the radiation was too conformal and instead would have been better delivered with controlled dose fall off to include regional nodes.
TBL: “Moving forward, it is important that standard target definitions be utilized in ongoing clinical trials evaluating the role of SBRT in pancreatic cancer.” | Chung, Adv Radiat Oncol 2024