Turning up the stereo in lung cancer

The landscape of lung cancer treatment is rapidly evolving with the clinical diffusion of newer surgical, medical and radiation treatment modalities. Stereotactic ablative radiotherapy (SABR, also known as stereotactic body radiotherapy or SBRT) is characterized by ultra-high doses of radiation delivered over a few fractions, largely enabled by advances in the radiation planning and delivery process. In this special issue of Therapeutic Radiology and Oncology, we discuss current paradigms and controversies on practical topics related to the use of lung SABR that face the modern oncologist in daily treatment decisions.

As lung SABR is generally well tolerated, its role in the potentially operable early-stage lung cancer patient is explored. On the other extreme, higher-risk scenarios in which the relative benefits of SABR need to be carefully considered include scenarios such as in central/ultra-central tumors, previously treated lung cancers, and in patients with co-existing interstitial lung disease. From a diagnostic point of view, common management questions that arise include the suitability of empiric lung SABR for a solitary pulmonary nodule that is suspicious for malignancy, and distinguishing fibrosis from recurrence following treatment. Looking toward the future, advances from both a technical (protons) and medical (immunotherapy) perspective are active areas of research.

We must also not forget that lung SABR is a highly technical endeavor, and therefore quality assurance is of utmost importance. Therefore, as this technology expands, ongoing collaborations between experienced and learning centres, whether in developed or developing regions, is encouraged. It is through such partnerships that the broader radiation oncology community will be able to expand this technology in a fashion that minimizes toxicity and ensures that the excellent outcomes that have been reported thus far are highly generalizable to all regions.

Acknowledgments

Funding: None.

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Therapeutic Radiology and Oncology for the series “Stereotactic Radiotherapy and Lung Cancer”. The article did not undergo external peer review.

Conflicts of Interest: The series “Stereotactic Radiotherapy and Lung Cancer” was commissioned by the editorial office without any funding or sponsorship. AVL served as the unpaid Guest Editors of the series and serves as the unpaid editorial board member of Therapeutic Radiology and Oncology from Sep 2019 to Aug 2021. JYC served as the unpaid Guest Editors of the series and serves as the unpaid editorial board member of Therapeutic Radiology and Oncology from May 2018 to May 2020. JY Chang—BMS: Research Grant; AstraZeneca: Consultant; Varian: Honorarium; Global Oncology One: Shareholder. Dr. Louie has received honoraria from Varian Medical Systems Inc. and AstraZeneca, unrelated to this work. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are 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/.

Alexander V. Louie

Joe Y. Chang