Prognostic value of Exhaled Microsatellite alterations at 3p in NSCLC patients

Our research group has recently been able to demonstrate and validate the possibility of studying of 3p microsatellite alterations (MAs) in the DNA extracted from the exhaled breath condensate (EBC) of healthy smokers and of subjects with non-small cell lung cancer (NSCLC). In light of the interest that has recently been aroused in the novel molecular staging protocol of lung cancer, the evaluation of the prognostic power of the genetic alterations involved in lung cancerogenesis, including 3p microsatellite alterations could be of clinical interest. Purpose: The aim of this study was to investigate the outcome predictive power of exhaled 3p microsatellite alterations in lung cancer patients. Patients and methods: Seventy-one NSCLC patients were enrolled in the study. All the subjects under study had already undergone a 3p microsatellite analysis of their EBC. A total of 56 patients were either given a follow-up of at least 102 weeks, or were followed up until death. Results: The number of 3p microsatellite alterations found in the exhaled breath condensate DNA exhibits a remarkable correlation with patients' survival. D3S2338 and D3S1289 account for the microsatellites with the highest positive prognostic power; loss of heterozygosis (LOH) D3S1289 has a negative prognostic value in adenocarcinoma while microsatellite instability (MI) and LOH D3S2338 influence survival in squamous cell carcinoma; and, independently of NSCLC stage, D3S1289 is associated with poor prognosis. Conclusions: In conclusion, 3p MAs in the DNA of exhaled breath condensate is strongly associated with NSCLC patients' survival. Our results suggest that it is possible to use the study of EBC MAs as an outcome predictor for lung cancer patients. © 2008 Elsevier Ireland Ltd. All rights reserved.