Stereotactic body radiation therapy in pancreatic cancer: the new frontier

Abstract

Pancreatic cancer (PCA) remains a disease with a poor prognosis. The majority of PCA patients are unable to undergo surgical resection, which is the only potentially curative option at this time. A combination of chemotherapy and chemoradiation (CRT) are standard options for patients with locally advanced, unresectable disease, however, local control and patient outcomes remains poor. Stereotactic body radiation therapy (SBRT) is an emerging treatment option for PCA. SBRT delivers potentially ablative doses to the pancreatic tumor plus a small margin over a short period of time. Early studies with single-fraction SBRT demonstrated excellent tumor control with high rates of toxicity. The implementation of SBRT (3–5 doses) has demonstrated promising outcomes with favorable tumor control and toxicity rates. Herein we discuss the evolving role of SBRT in PCA treatment.

Keywords::

• locally advanced
• pancreatic cancer
• radiation oncology
• radiation therapy
• stereotactic body radiation therapy

Acknowledgement

Claudio X Gonzalez Family Foundation, Flannery Family Foundation, Alexander Family Foundation, Keeling Family Foundation, DeSanti Family Foundation, McKnight Family.

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Pancreatic cancer (PCA) is one of the most lethal cancers in the USA, and despite aggressive combined modality treatment, 5-year survival remains less than 5%.

• It has been shown that up to 30% of patients with PCA die from isolated local progression of disease.

• Early stereotactic body radiation therapy (SBRT) studies had higher toxicity rates likely due to lack of fractionation, inadequate motion management and lack of specific dose constraints for organs at risk.

• SBRT regimens for unresectable PCA patients have resulted in comparable rates of local control to those of single-fraction SBRT, but with lower incidence of high-grade toxicities.

• New data point to neoadjuvant SBRT possibly aiding in margin-negative resection and improving the likelihood of surgical resection among PCA patients who were initially presumed to have unresectable or borderline resectable tumors.

• SBRT appears to be promising from a clinical outcome, quality of life and health economics perspective for patients with PCA.

Notes

CBCT: Cone beam computed tomography; GTV: Gross tumor volume; ITV: Internal target volume; IO: Intravenous/oral; LN: Lymph node; MLC: Multi-leaf collimator; OAR: Organ at risk; PET/CT: Positron emission tomography/computed tomography; PRV: Planning organ at risk volume; PTV: Planning target volume; SBRT: Stereotactic body radiation therapy.