Ipsilateralbreasttumourrecurrenceinhereditarybreastcancer followingbreast-conservingtherapy C.Seynaeve a, * ,1 ,L.C.Verhoog a,1 ,L.M.C.vandeBosch a ,A.N.vanGeel b , M.Menke-Pluymers b ,E.J.Meijers-Heijboer c ,A.M.W.vandenOuweland c ,A.Wagner c , C.L.Creutzberg d,e ,M.F.Niermeijer c,f ,J.G.M.Klijn a ,C.T.M.Brekelmans a a Family Cancer Clinic, Department of Medical Oncology, Erasmus University Medical Centre-Daniel den Hoed Cancer Centre, Groene Hilledijk, 301, 3075 EA Rotterdam, The Netherlands b Family Cancer Clinic, Department of Surgical Oncology, Erasmus Medical Centre-Daniel den Hoed Cancer Centre, Rotterdam, The Netherlands c Family Cancer Clinic, Department of Clinical Genetics, Erasmus Medical Centre, Rotterdam, The Netherlands d Family Cancer Clinic, Department of Radiation Oncology, Erasmus Medical Centre-Daniel den Hoed Cancer Centre, Rotterdam, The Netherlands e Present address: Department of radiotherapy, Leiden University Medical Centre, Leiden, The Netherlands f Present address: Dept. of Clinical Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands Received9September2003;receivedinrevisedform3December2003;accepted7January2004 Abstract Theoverallrateofanipsilateralbreasttumourrecurrence(IBTR)afterbreast-conservingtherapy(BCT)rangesfrom1%to2% peryear.RiskfactorsincludeyoungagebutdataontheimpactofBRCA1/2mutationsoradefinitepositivefamilyhistoryfor breastcancerarescarce.WeinvestigatedIBTRafterBCTinpatientswithhereditarybreastcancer(HBC).Throughourfamily cancerclinicweidentified87HBCpatients,including26BRCA1/2carriers,whounderwentBCTbetween1980and1995(cases). Theywerecomparedto174patientswithsporadicbreastcancer(controls)alsotreatedwithBCT,matchedforageandyearof diagnosis.Medianfollowupwas6.1yearsforthecasesand6.0yearsforcontrols.Patientandtumourcharacteristicsweresimilar inbothgroups.AnIBTRwasobservedin19(21.8%)hereditaryand21(12.1%)sporadicpatients.Inthehereditarypatientsmore recurrencesoccurredelsewhereinthebreast(21%versus9.5%),suggestiveofnewprimaries.Overall,theactuarialIBTRratewas similarat2years,buthigherinhereditaryascomparedtosporadicpatientsat5years(14%versus7%)andat10years(30% versus16%)(P=0.05).Post-relapseandoverallsurvivalwasnotdifferentbetweenhereditaryandsporadiccases.Hereditarybreast cancerwasthereforeassociatedwithahigherfrequencyofearly(2–5years)andlate( > 5years)localrecurrencesfollowingBCT. Thesedatasuggestanindicationforlong-termfollowupinHBCandshouldbetakenintoaccountwhenadditional‘risk-reducing’ surgeryafterprimaryBCTiseventuallyconsidered. # 2004ElsevierLtd.Allrightsreserved. Keywords: Breast cancer; Ipsilateral breast tumour recurrence; Breast-conserving therapy; Hereditary breast cancer; BRCA1; BRCA2; Historical cohortstudy 1. Introduction Breast-conserving surgery with subsequent radiation therapy (breast-conserving therapy; BCT) has become the treatment of choice in women with early-stage breast cancer (BC). It was found to be equivalent to mastectomyfordistantdisease-freeandoverallsurvival [1–4]. However, following BCT, recurrences in the preserved ipsilateral breast occur at an average rate of 1–2%peryear,accumulatingtoapproximately15%after 10years [1,2,5,6].Whileearlyrecurrencesmostprobably represent outgrowth of residual disease, therefore occurring in the vicinity of the original tumour, late recurrences are suggestive of a new primary tumour. Accordingly,thelatterarefoundmoreofteninanarea distinctfromthesiteoftheprimarybreasttumour [7,8]. Patientswithbreastcancerwhodevelopanipsilateral recurrence(IBTR)haveanincreasedriskofdeveloping distant metastatic disease, indicative of the prognostic 0959-8049/$-seefrontmatter # 2004ElsevierLtd.Allrightsreserved. doi:10.1016/j.ejca.2004.01.017 EuropeanJournalofCancer40(2004)1150–1158 www.ejconline.com * Corresponding author. Tel.: +31-10-4391754; fax: +31-10- 4391003. E-mail address: c.seynaeve@erasmusmc.nl(C.Seynaeve). 1 Bothauthorscontributedequallytothestudy.