P38. Extraesophageal reflux disease and lung cancer

Introduction: Gastroesophageal reflux disease is recognised as a substantial risk factor of esophageal cancer, as well its extraesophageal form should be a risk factor of pharyngeal and laryngeal cancers. EER should take an active part in the exacerbations of COPD, interstitial pulmonary processes and of extrinsic allergic alveolities. Those diseases are also associated with increased risk of lung cancer.

Methods and patients: We used commercial diagnostic test Pep test, we tested saliva or sputum. A detection limit of the method is 25 ng/mL. We performed investigations of pepsin levels in saliva/sputum in patients suffering from verified lung cancer. A method of estimation is described on Peptest, RD Biomed Limited, Hull UK, (www.peptest.co.uk).

Results: From June 2013 till August 2014 we received Peptest results from 44 patients suffering from verified lung cancer, there were 30 men and 14 women. Positive results were found in 31 patients (75.6%), positive results in the range of 59-250 ng/mL of pepsin concentration had 22 patients (24.4%), modestly positive results of range 25-57 ng/mL of pepsin were found in nine patients (21.6%l), in 10 patients (24.4%) the results were negative, in three patients we observed a failure of test due to abnormal suptum viscosity.

Conclusions: Extraesophageal reflux has been documented by detection of pepsin in saliva/sputum or other respiratory secretions. Pepsin should act as a cancerogen in upper or lower airways, or should be able to potentiate the cancerogenic effects of other chemical cancerogens, e.g., smoking related. Pepsin and bile acids contained in refluxate should be able to induce not solely the cancer growth, but also the exacerbations of other pulmonary diseases frequently associated with lung cancer, e.g., COPD, IPF, bronchiectasis and to bring some inflammatory complications of the course of treatment of lung cancer. Investigation of EER should be considered in lung cancer patients also in the time of preoperative investigation to prevent postoperative inflammatory complications.

Keywords: Gastroesophageal reflux; lung cancer