KEY POINTS
- This narrative review screened 1,247 records and included 186 studies covering oligometastatic pancreatic ductal adenocarcinoma, SBRT, systemic therapy, biomarkers, technical delivery and ongoing trials.
- Available predominantly retrospective evidence suggests one-year local control of approximately 70–80% for pancreatic primary tumors, 85–95% for lung metastases, and >95% for lymph-node metastases after SBRT.
- Reported median overall survival after SBRT-based consolidative therapy is generally 12–18 months, compared with historical survival of roughly 9–12 months with systemic therapy alone. These comparisons are highly vulnerable to selection bias.
- The randomized EXTEND trial provides the strongest pancreas-specific signal to date: adding comprehensive metastasis-directed therapy to systemic therapy improved progression-free survival in selected oligometastatic pancreatic cancer, but an overall survival benefit has not been established.
- The review favors a systemic-therapy-first approach in synchronous disease, typically using 4–6 cycles of induction chemotherapy followed by restaging. A period of 3–6 months can help identify patients whose disease remains biologically limited before committing to consolidative local therapy.
- Technical recommendations emphasize multi-fraction SBRT because of the proximity of the duodenum and stomach. Common pancreatic-primary regimens are 33–40 Gy in 5 fractions, with the review citing duodenal and stomach maximum-dose constraints around 35 Gy.
- Proposed biomarkers including circulating tumor DNA clearance, KRAS subtype, SMAD4 status and metabolic imaging remain investigational. Dedicated quality-of-life data after SBRT in oligometastatic pancreatic cancer are essentially absent.
CLINICAL TAKEAWAY
SBRT is increasingly reasonable as a consolidative component of multidisciplinary treatment for carefully selected oligometastatic pancreatic cancer rather than purely for palliation. The key unresolved issue is patient selection: systemic therapy remains the backbone, and neither biomarker-guided selection nor an overall survival benefit from SBRT has yet been prospectively established.