COPD and lung cancer are interrelated diseases with substantial mortality and most probably an immunological link may exist between the two diseases.15 However, their pathophysiologic mechanisms are not yet fully understood.16 The increased risk of lung cancer in COPD patients suggests the existence of a two‐fold altered cell‐mediated immune response in COPD patients: dysregulation of T‐cells in the lungs and T‐cell exhaustion.16 Activation of nuclear transcription factor (NF)‐kB may have a crucial role in the development of lung cancer from COPD. This evidence concerns the gene NFKB1 and lung cancer.