To review the indications and outcomes following stereotactic ablative radiotherapy (SABR) for the treatment of primary non-small cell lung cancer (NSCLC). To discuss the expected post treatment CT appearances in the early and late phases and to describe the imaging features of local recurrence. We will also review common complications encountered with SABR.

Lung cancer is the leading cause of cancer death in Ireland and non-small cell lung cancer accounts for 75 - 85% of lung cancer diagnoses (1, 2). Approximately one quarter of patients present with early stage NSCLC for which surgical resection is the treatment of choice. Not all of these patients will be deemed fit to undergo resection however. SABR is indicated in early stage NSCLC in patients who are unfit for or decline surgery. The increasing use of CT has resulted in an increase...

Indications and Outcomes Stereotactic ablative radiotherapy (SABR) is delivered in several fractions, typically 3-8, and precisely administers high doses of radiation, in excess of 100 Gy, to the lung tumour over 1-3 weeks in an outpatient setting (3, 4). Complex beam arrangements reduce the impact on adjacent normal lung and mediastinal structures (3). SABR is indicated in early stage NSCLC in patients who are unfit for or decline surgery and in some cases of recurrent NSCLC (5). SABR has been reported to obtain locoregional control...

SABR provides excellent rates of locoregional control for early stage NSCLC with comparable disease-free and overall survival rates to conventional surgery. While in-field recurrence is uncommon, knowledge of the variation of post SABR imaging changes is required in order to distinguish thesefrom recurrence. Follow-up imaging protocols are yet to be standardised.

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