No advantage of post-operative radiotherapy in patients with stage IIIA N2 NSCLC

The merits of post-operative radiotherapy (PORT) in completely resected non-small cell lung cancer (NSCLC) patients have been under debate for many years. The prospective phase 3 LungART trial now demonstrated that PORT cannot be recommended as a standard of care in all completely resected stage IIIA N2 NSCLC patients [1].

To evaluate the value of PORT in completely resected stage IIIA N2 NSCLC patients, the phase 3 LungART trial was developed. Patients were eligible if they were performance status 0-2, had a complete resection with nodal exploration, and proven N2 disease; prior (neo)-adjuvant chemotherapy was allowed. LungART enrolled 501 patients: 252 patients were randomised to PORT (54 Gy/27-30 fractions), and 249 to the control arm (no PORT). In the PORT arm, 96% of the patients received the dose of 54 Gy.

Median disease-free survival (DFS) in the PORT arm was 30.5 months versus 22.8 months in controls (HR 0.85; P=0.16). DFS at 3 years follow-up was 47.1% and 43.8% in the PORT and control arm, respectively. However, the nature of the first events were different between the 2 treatment arms. In the PORT arm, 25% of the first events were mediastinal relapses and 14.6% were deaths; whereas in the control arm, 46.1% of the first events were mediastinal relapses and 5.3% were deaths. Overall survival at 3 years was comparable: 66.5% for PORT and 68.5 for controls. In the PORT arm, 16.2% of deaths were due to cardio-pulmonary causes versus 2% in the control arm and 5.1% of deaths were due to second primary tumours versus 1.0% in the control arm. In line with this, late cardiac/pulmonary toxicity was doubled in the PORT arm compared with the control arm (10.8% vs 4.9%, respectively). Also, more secondary cancers were observed in the PORT arm compared with the control arm (11.1% vs 7.2%, respectively). Therefore, PORT cannot be recommended as a standard of care in all completely resected stage IIIA N2 NSCLC patients.

1. Le Pechoux C, et al. An international randomized trial, comparing post-operative conformal radiotherapy (PORT) to no PORT, in patients with completely resected non-small cell lung cancer (NSCLC) and mediastinal N2 involvement: Primary end-point analysis of LungART (IFCT-0503, UK NCRI, SAKK) NCT00410683. ESMO 2020 Virtual Meeting, abstract LBA3.

Posted on 25 November, 202024 November, 2020