Incidence and outcome of lung cancer in patients with chronic respiratory failure

Rationale: There is few data available regarding the incidence of lung cancer (LC) and treatment efficacy in patients with chronic respiratory failure (CRF) under long-term oxygen therapy (LTOT). Methods: In this single center study, charts from 7631 patients under LTOT from 2009 to 2018 were retrospectively reviewed. Patients diagnosed with LC were included in the subsequent analysis, for tumor characteristics, underlying respiratory failure, cancer treatment and outcome . Results: A total of 29 patients developped LC during the study period (Incidence rate 0.38±0.18%). At LC diagnosis, patients were 70 [66 to 78] years old and on LTOT for 2.2 [1.2 to 3.9] years. Histology was adenocarcinoma (n=9), squamous cell (n=12), small-cell lung cancer (n=2) and unknown (n=6). 14/29 patients had stage IV at diagnosis. Ten patients did not received specific LC treatment, whereas 7 patients received chemotherapy, 4 concomitant radio-chemotherapy, 4 exclusive radiotherapy, 2 tyrosine kinase inhibitors, and one tumor was surgically removed. Underlying respiratory diseases were: COPD (n=25), interstitial pneumonia (n=3), pulmonary hypertension (n=1). Overall median survival from LC diagnosis was 285 [69 to 566] days, 727 days in patients treated by surgery or radiotherapy (±chemotherapy) and 241 days in those treated by chemotherapy alone (p= 0.054). Conclusion: LC incidence in patients under LTOT appears low. Specific non surgical LC treatment could be administered in 2/3 of the patients with results comparable to non surgical patients without CRF.