What proportion of patients with stage I NSCLC seen in the oncology clinic are treated with SABR?

Abstract

Introduction: Stereotactic radiotherapy (SABR) is standard of care for inoperable stage I NSCLC. The proportion of patients with stage I NSCLC treated with SABR is a lung cancer quality measure at this cancer centre and is < 50%. This retrospective analysis aims to validate the accuracy of this quality measure, and explores the reasons why patients did not receive SABR. Methods: Electronic patient records (EPR) were reviewed for all patients with stage I NSCLC first seen in the oncology clinics between 01/06/2018 and 31/12/2018. Results: Of the 119 patients with stage I (T1a=17; T1b=56; T1c=3; T2a=43; T2b=0) disease, 54 (45.4%) had biopsy proven NSCLC (20 squamous; 34 non-squamous). Median ECOG performance status (PS) was 2 (PS 0=6; PS 1=38, PS 2=42, PS 3=33). The lung cancer MDT referred 45 (37.8%) of these patients for surgical assessment also. 87 (73.1%) patients received radiotherapy, 15 (12.6%) received surgery, and 17 (14.3%) did not receive active treatment. SABR was delivered to 52 (43.7%) of patients (54Gy/3 fractions(F)=6, 60Gy/5F=40, 60Gy/8F=6), 9 received 60Gy/15F, and 28 received 55Gy/20F. For the 52 non-surgical patients not treated with SABR, 39 had a justification for this decision recorded in the EPR, including tumour too close to organs at risk (OAR) (proximal bronchial tree (5), heart/ great vessels (2), spinal cord (6)), treatment volume too large (4), PS/ co-morbidities (10), and patient choice (6). Conclusion: Whilst <50% of all patients with stage 1 NSCLC seen in the oncology clinic received SABR, >70% treated with radiotherapy received SABR or an accelerated hypofractionated regimen (60Gy/15F). The most common reason for not offering SABR was vicinity of tumour to OAR. Latest UK SABR Consortium guidance on treating central tumours could increase the proportion of patients treated with SABR.