Chemical characterization of exhaled breath to discriminate patients with Malignant Pleural Mesothelioma from subjects with similar professional asbestos exposure

MalignantPleuralMesothelioma(MPM)isanaggressiveneoplasm that isveryoftenassociatedwithasbestosexposure.MPMdiagnosisisdifficult, veryoftenrequiringinvasiveapproachessuchasthoracoscopy.Exhaledbreath containshundredsofdifferentvolatileorganiccompounds(VOCs)whichmaybe usedfordiagnosisofvariouspulmonaryandsystemicdisordersincludinglung cancer. Methods: Weenrolled13patientswithanestablisheddiagnosisofMPM,13 healthy controls(HC),and13subjectswithaprofessionalexposuretoasbestos without MPM(EXP).Tedlarbagswereusedtocollecthumanbreath.Samples werecollectedusingasorbent-trapfollowedbythermaldesorptionandanalysis by gaschromatographwithananalyticalmassspectrometer(GC-MS). Results: AnalysisshowedthatthemostabundantVOCs(>15 ng/L)inthein- vestigatedsampleswerecyclopentaneand cyclohexane.Thechemicalprofilewas differentforthesamplesclasses:EXPandMPM,showedalteredlevelsoftoluene, xylene, benzaldehyde,trimethylbenzene, limonene, 2-ethyl-1-hexanol,acetophe- none, cyclopentane.MPMpatientsshowed higherconcentrationofcyclohexane (meanvalue=339.31ng/L)comparedtoEXP(meanvalue=173.06ng/L)and controls(meanvalue=30.68ng/L).ByusingtheTukeyHSDtestitwasfound that cyclohexaneconcentrationforMPMwas significantlydifferentcomparedto HC (p=0.006)whereastheconcentrationforEXPwasnotsignificantlydifferent both comparedtoMPM(p=0.146)andcontrolgroup(p=0.285). Conclusions: BreathAnalysisbyGC-MSmayplayapotentialroleinthenon- invasiveassessmentofMPM