title: Primary adenoid cystic carcinoma of the tracheobronchial tree: A decade-long experience at a health centre in Mexico.
abstract: BACKGROUND
  Mexico's National Institute of Respiratory Diseases (NIRD) is a third-level national reference center. Primary adenoid cystic carcinoma (PACC) is an uncommon neoplastic disorder; hence improvements in the description of this disease are needed.
  
  
  METHODS
  This is a retrospective clinical study based on all consecutive patients with pathological diagnoses of PACC seen at the NIRD between January 1, 2000 and December 31, 2009.
  
  
  RESULTS
  We identified 9 cases of PACC (67% female) out of a total of 2,634 patients with lung cancer seen during the period analyzed. The mean age of those 9 patients was 41 years (IQR 36-57), and the frequency of PACC at our center was 0.3%. It is important to note that 67% of those patients had a history of smoking and that 6 of the 9 had the antecedent of previous exposure to biomass fuel smoke. Baseline arterial blood gas analyses revealed a median of 61 mmHg for pO(2) and 28.5 mmHg for pCO(2). Median FVC was 78%, while FEV(1) was 77% with an FEV(1) /FVC ratio of 78. Death occurred in 56% of cases, and the median survival time was 17 months (IQR 6-26) after the initial diagnosis.
  
  
  CONCLUSIONS
  The frequency of tracheobronchial PACC among patients with lung cancer was similar to that previously reported (0.3%). According to our results, lung function has no specific phenotype in this disease; however, some abnormalities could be related to potential risk factors such as tobacco use and exposure to biomass fuel smoke.
authors.affiliation: Department of Respiratory Physiology, National Institute of Respiratory Diseases (Instituto Nacional de Enfermedades Respiratorias, I.N.E.R.), Mexico City, Mexico.
authors.forename: Arturo
authors.initials: A
authors.lastname: Cortés-Télles
authors.forename: Daniel
authors.initials: D
authors.lastname: Mendoza-Posada