Objective:Differentiatedthyroidcarcinomas(DTCs)areclassifiedintopapillarythyroidcarcinoma(PTC)andfollicularthyroidcarcinoma(FTC).DTCsareanalyzedasasinglegroupinclinicalstudiesthatinvestigatedtheprognosticfactorsandprognosisofthesemalignancies.However,thebiologicalbehaviorsofthesecarcinomassignificantlydiffer.Inthepresentstudy,weaimedtodetectdifferencesintheoutcomesbetweenPTCandFTCinMansouraUniversityHospitalinEgypt.Methods:Atotalof558patientswithhistologicallyproventhyroidcarcinomasfromJanuary2003toDecember2012wereretrospectivelyenrolled.Theclinicalandpathologicaldataofpatientswerereviewed.Results:Largeprimarytumorsize,lymphnodeinvolvement,extrathyroidextension,anddistantmetastasisweresignificantpoorprognosticfactorsforoverallsurvival(OS)inoldPTCpatients.Coxhazardanalysisshowedthatthepatient'sage,extrathyroidextension,anddistantmetastasisweretheonlyindependentprognosticfactors.InFTCpatients,onlythedistantmetastasisanddegreeoftumorinvasionweresignificantpoorprognosticfactorsinOSunivariateanalysis.However,thesefactorswerenonsignificantinmultivariateanalysis.The10-yearOSrateswere97%and89%forPTCandFTC,respectively(P=0.003).The10-yeardisease-freesurvival(DFS)rateswere77.2%inPTCvs.65%inFTC(P=0.179).Conclusion:ThesignificantprognosticfactorsvarybetweenthetwotypesofDTCs.Therefore,PTCandFTCpatientsneedtobeanalyzedandreportedindependently.PTCsurvivaliswidelyandsignificantlyaffectedbyage,extrathyroidextension,anddistantmetastasis.Bycontrast,thesefactorswerenonsignificantinFTC,whichshowedpoorersurvivalthanPTC.
