Developing lung cancer in COPD: Possible role of carrying Alpha-1 antitrypsin deficiency variants.

Introduction: Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and airway inflammation, with a prevalence of 10.1%. Among the many causes of COPD, Smoking is the leading and another big cause is (AATD α1-antitrypsin deficiency)' an inherited disorder. Prevalence of COPD patients is 1.9%. World Health Organization (WHO) advice all COPD patients' AATD rate to be screened at least once during their life.The prevalence of AATD in the general population ranges from 1:2,000-5,000 in parts of Europe and from 1 to 5,000-10,000 in the United States and Canada. Case 1: An 81-year-old male patient with COPD. In computed tomography (CT) of the thorax, mass in the right lower lobe and a nodule in the right upper lobe were detected. The biopsy from right bronchial entrance via fiberoptic bronchoscopy (FB) yielded squamous cell carcinoma (SCC). AAT level was 169 mg/dL (ref. range: 90-200 mg/dL). M/P lowell allele was detected in genetic analysis. Case 2: A 45-year-old male patient with COPD. Conglomerated lymhadenomegaly in the paratracheal area was detected in CT. The biopsy from mucosal infiltrates initiating from the entrance of the right upper lobe to the anterior segment revealed SCC. His AAT level was 190 mg/dL (ref. range: 90-200 mg/dL) and the genetic analysis demonstrated M/I mutation. Case 3: A 64-year-old male COPD patient. In thorax CT, a 24 mm diameter parenchymal nodule in the left lower lobe was detected. Transthoracic fine needle aspiration biopsy from the left lung nodule showed SCC. His AAT level was 196 mg/dL (ref. range: 90-200 mg/dL) and M/P lowell allele was detected in the genetic analysis. Discussion: AAT deficiency can cause early-onset of COPD, manifested with emphysema and chronic bronchitis. It has been suggested that AATD is associated with an increased risk of many types of cancer. Although the relationship between AATD or variant carriage and LC histopathology is not clear in the literature, it was detected as squamous cell carcinoma in our cases. We infer that unmeasurable lung damage is more prevalent in heterozygous patients and we believe that sharing our results may draw more attention in this regard.