An association between lung cancer and gastroesophageal reflux

Abstract

18195 Background: Many studies have demonstrated the association between gastroesophageal reflux and a wide spectrum of extra-esophageal complications of the upper aerodigestive tract. A major risk factor for adenocarcinoma of the esophagus is intestinal metaplasia, which occurs as a consequence of GERD. In addition to that, laryngoscopy and bronchoscopy can reveal findings with a high positive predictive value for the presence of GERD. The probable role of this chronic irritative disorder as a causative agent in carcinoma of the lung has not been studied. The aim of our study is to determine the correlation between GERD and lung cancer. Methods: A hospital based retrospective age, sex, ethnicity and smoking matched case control study was performed in a tertiary care center. The medical records of 325 patients diagnosed with lung cancer and 325 matched control cases were reviewed between January 2003 and December 2005. We looked at many aspects at the presentation of the disease including right or left sided lung cancer, pathology of the tumor and the presence of other co-morbid conditions. GERD diagnosis was determined either by endoscopy, manometry or clinical diagnosis retrospectively. Results: Among the 325 lung cancer patients 75 (23%) were found to have GERD at the time of diagnosis. On the other hand, only 46 (15%) patients were found in the control group. By using the Fisher Exact Probability Test there was a statistically significant increase in the incidence of GERD among lung cancer patients compared to the control group at the time of diagnosis (p=0.0046, 95% CI = 1.21- 2.73 and Odds Ratio =1.82). Patients with lung cancer were also divided into 5 major categories: Adenocarcinoma (n=110, 34%), Squamous cell carcinoma (n=70, 22%), Small cell carcinoma (n=40, 12%), NSCLCA (n=52, 16%) and Others (e.g. large cell, neuroendocrine...etc) (n=53, 16%). Conclusion: Our analyses suggest an association between GERD and lung cancer. For this reason we may consider GERD as a possible co-promoting factor of lung cancer in some patients. No significant financial relationships to disclose.