Pathogenesis:（發(fā)病機制Theydevelopasresultofinvolutionofbreasttissuewhichstartsinthelate20'sandandearly30'sandmaylastforover20years.Involutionistheprocesswherethetissuebetweenthelobules(stromaltissue)isrecedbyfibroustissueandtheregressionofthecellsliningthelobules.Lobulesarethebasicunitoftissue,whichmakeupbreast.Whenthereisaminoraberrationinthisnormalprocessitleadstotheformationofmicrocysts.Theyresultfromthekinkingorcompressionoftheductsbythisfibroustissueorbytheactivesecretionoffluidfromthecells.Theenlargementofmicrocystsleadstothedevelopmentofmacrocysts.Pathology（病理學Normalbreast.Midtransversescanofanormalbreast.Thefibroglandularparenchymaisechogenic(arrowheads)andissurroundedbyhypoechoicfat.AsimplebreastAcomplexbreastSedimentarymovementmaybevisiblebyscanningthepatienterect.Fineneedleaspirationandcytologicalassessmentcanconfirmthediagnosis.Attheleast,afollow-upultrasoundshouldbeAsimplecystadjacenttoacomplexcyst,(confirmedbyFNAtobeahaemorrhagiccyst)Cysts.Cystsusuallyrevealthinwallsandthroughtransmission(A).Aninflamedcyst(B)revealsAthickedematouswall(arrow)withinternallayeringofthick/thinfluid(arrowhead).A(C)revealsdiffuselow-levelechoesinthecyst.[Imagingfindings]:X-raymammography(A~C)showsthebreasttoseeroundoroval,smoothedges,uniformdensitydenseshadow;visible"transparenthalo"sign multiplebreastcysts.Clinicalpresentation（臨床表現(xiàn)Theyoftendonotcauseanysymptomsinmanywomen.Patients awareofbreastlumpaccidentally.Inothercasestheycancausepainprobablyincreaseinsizeorleakagefluidintothesurroundingtissuescausingsecondaryirritation.Evenasmallincreaseinvolumeforunknownreasonshasdisproportionateeffectinpressureinsidethecystresultinginpain.Thisexinsthefactthatsymptomsimproveafteraspirationoffluidfromit.Multiplecystsarefrequentlynotfeltduetothelaxityofthecystandtheyeasilymergewiththesurroundingbreasttissue.Whenoneorfewofthecystincreaseinsizetheycanbesotensetheyfeelhardtofeelonoccasionsimulatingcarcinoma.Clinically,maybefluctuate.Occasionally,non-fluctuantcystsmayresembleacarcinoma.Paincanbeapresentingsymptomandthehistoryisofshortandrapidonset.Thetotalnumberofpalpablebreastcystsvariesgreatlybetweenindividualwomen,themajorityhoweverdeveloonlyasinglecyst,30%havingbetweentwoandfivecystsandtheremaindermorethanthisnumber.Diagnosis（診斷Thecysticnatureofabreastlumpcanbeconfirmedbyultrasoundexamination,aspiration[3](removalofcontentswithneedle),ormammogram.Ultrasoundcanalsoshowifthecystcontainssolidnodules,asignthatthelesionmaybepre-cancerousorcancerous.Examinationbyacytopathologistofthefluidaspiratedfromthecystmayalsohelpwiththisdiagnosis.Commonly,cystsaredetectedwiththehelpofmammograms.However,themedicalhistoryandphysicalexaminationalsoyanimportantroleinestablishinganaccuratediagnosis.Duringthesetests,thedoctorwilltrytofindoutasmuchinformationaspossibleregardingthesymptomsthepatienthasexperienced,theirintensityanddurationandthephysicalexaminationisperformedregularlytocheckforotherabnormalitiesthatmayexistwithintheThismammogramdemonstratesasuspiciouslesionthatcouldbeacarcinomaorjustanareaofpronouncedsclerosiswithfibrocysticchanges.Onbiopsy,thiswasbenign. Breastcystsdon'trequiretreatmentunlessacystislargeandpainfulor fortable.Inthatcase,drainingthefluidfromabreastcystcaneaseyoursymptoms.[1]TypicaltreatmentinvolvesaNeedleaspirationbiopsy.Aspiratedcystsoftenrecur(comeback);definitivetreatmentmayrequiresurgery.Drainingthefluidandthenwaitingforthecysttoresolveitisthemaintreatmentappliedinthesecases.Moreover,cyststhatareaspiratedandthefluidlooksnormaldonotrequireanyothermedicalattentionapartfromfollowing-uptomakesureitcompleydisappeared.Yet,hormonetherapybythemeansoforalcontraceptivesissometimesprescribedtoreducetheirrecurrenceandtoregulatethemenstrualcycleofthepatient(whichislikelytocausetheminthefirstce).Danazolmayalsobeprescribedtotreatthisconditionanditisusuallyconsideredinpatientsonwhomthenon-medicaltreatmentfailsandthesymptomsareintense.Surgicalremovalofabreastcystisnecessaryonlyinafewunusualcircumstances.Ifan fortablebreastcystrecursmonthaftermonth,orifabreastcystcontainsblood-tingedfluidanddisysotherworrisomesigns,surgerymaybeconsidered.[7]Thedevelopmentofbreastcystsmaybepreventedtosomedegree,accordingtothemajorityofthespecialists.The mendedmeasuresoneisabletotakeinordertoavoidtheformationofthecystsincludepracticinggoodhealthandavoidingcertainmedications,Eagletonorlactosemayalsocontributetocystdevelopment.Eatingabalanceddiet,takingnecessaryvitaminsandsupplements,gettingexercise,andavoidingstress.[8]Althoughcaffeineconsumptiondoesnothaveascientificallyprovedconnectionwiththeprocessofcystdevelopment,manywomenclaimthattheirsymptomsarerelievedifavoidingit.Somedoctors mendreducingtheamountofcaffeineinone'sdietintermsofbothbeveragesandfoods(suchaschocolate).Alsoreducingsaltintakemayhelpinalleviatingthesymptomsofbrea