Revisiting radiotherapy for pancreatic cancer

Pancreatic cancer is the eighth most common cancer diagnosed in the United States (US) yet the third deadliest. This devastating disease is estimated to become the second leading cause of cancer deaths by 2030 largely due to the high rate of occult metastatic disease and significant tumor heterogeneity, rendering unselected therapies ineffective. Poor systemic control combined with high metastatic potential has likely contributed to the failure of multiple randomized controlled studies investigating the potential benefits of radiotherapy. As a result, the role of radiotherapy in the management of pancreatic cancer patients has been met with skepticism due to these conflicting clinical trial results from the US and Europe, leaving the scientific community at a crossroads.

During the past decade we have seen incremental but significant improvements in patient outcomes coincident with the widespread adoption of effective multi-agent chemotherapeutic regimens such as gemcitabine/Abraxane and FOLFIRINOX in the metastatic, unresectable and most recently, resectable setting. It is likely that these regimens have in large part contributed to improving the 5-year survival rate to 9%. This recent progress in the control of known and occult micrometastatic disease has again highlighted the corresponding importance of local control. Indeed, in the recently reported ESPAC-4 trial comparing adjuvant standard of care gemcitabine to gemcitabine and capecitabine in patients with resected pancreatic cancer (Neoptolemos et al., Lancet 2017), approximately 50% of patients had local recurrences, of which 28% were isolated. Simultaneous improvements in genomic assays, novel targeted small molecule and antibody-based therapies, as well as technologies used to deliver and assess response to radiotherapy have led to renewed investigation of radiotherapy for pancreatic cancer and are presented in this special issue of Annals of Pancreatic Cancer (APC).

In this series, we will hear from gastrointestinal radiation oncology key thought leaders from distinguished academic centers across the US. Each field expert will provide a scientific review, a critical assessment and offer their opinion on chief topics within the pancreatic cancer and radiotherapy landscape.

Acknowledgments

I would like thank to Dr. Zheng and the entire Editorial team of APC for commissioning and assisting with publication of this informative issue.

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Annals of Pancreatic Cancer for the series “Radiotherapy and Pancreatic Adenocarcinoma”. The article did not undergo external peer review.

Conflicts of Interest: The author has completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/apc.2018.08.01). The series “Radiotherapy and Pancreatic Adenocarcinoma” was commissioned by the editorial office without any funding or sponsorship. RT served as the unpaid Guest Editor of the series and serves as the unpaid Associate Editor of Annals of Pancreatic Cancer. The author has no other conflicts of interest to declare.

Ethical Statement: The author is accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

Richard Tuli