DIAGNOSISOFLIMITEDADENOCARCINOMAOFTHEPROSTATEDiagnosisofProstateCancerUseasystematicapproachtothediagnosisofprostatecancerbasedonspecificarchitectural,cytological,andancillaryfeatures.

Diagnosticcriteriaoflimitedadenocarcinomaoftheprostateonneedlebiopsy(Epstein:HumPathol1995)Withtheexceptionofthreefindingsthatbythemselvesarespecificforcancer,thediagnosisofprostatecancerisbasedonaconstellationoffeatures.FeaturesFavoringTheDiagnosisofAdenocarcinomaAbnormalarchitecturalpatternNuclearenlargementNuclearhyperchromasiaProminentnucleoliMitotic/apoptoticfiguresAmphophiliccytoplasmBluemucinoussecretionsPinkamorphoussecretionsCrystalloidsFeaturesDiagnosticofAdenocarcinomaPerineuralinvasionGlomerulationsMucinousfibroplasia(collagenousmicronodules)

Perineuralinvasion,mucinousfibroplasia,andglomerulations:diagnosticfeaturesoflimitedcanceronprostateneedlebiopsy.Baisden,Kahane,&Epstein(AJSP1999)PerineuralandIntraneuralInvolvementbyBenignGlands Perineuralinvolvementbybenignprostaticglandsonneedlebiopsy.Ali&Epstein(AJSP2005)CancersMimickingBenignGlandularProliferationsPseudohyperplasticprostatecancerFoamyglandprostatecancerAtrophicprostatecancerAdenocarcinomawith

AtrophicFeaturesCanbeseendenovoorinprostatestreatedwithhormonaltherapyInbiopsyorTURPmaterial,mosthavenohistoryofanti-androgentherapy Adenocarcinomaoftheprostatewithatrophicfeatures.Cina&Epstein(AJSP1997)

DiagnosticCriteriaInfiltrativegrowthpatternMacronucleoliPresenceofadjacentnon-atrophiccancerPseudohyperplasticAdenocarcinoma Unusualvariantofprostateadenocarcinomawitharchitecturallybenign-appearingglandsfirstreportedbyHopkins.Patternsinclude:GlandswithpapillaryinfoldingBranchingglandsLargedilatedglandsFoamyGlandCarcinomaDespiteblandcytologicappearance,correspondingRP’sshowed:Gleasonscore5-7in93%EPEin>50%Positivemarginsin27%Metastasestopelvicnodesin13%Prostaticcarcinomawithabundantxanthomatouscytoplasm:Foamyglandcarcinoma.Nelson&Epstein(AJSP1996)Features

AgainstTheDiagnosisofAdenocarcinoma

AtrophiccytoplasmMerginginwithbenignglands(r\oadenosis)CorporaamylaceaInflammationAdjacentPIN(r\oPINATYP)MostCommonMimickersofCanceronNeedleBiopsy

PartialAtrophyinProstateNeedleCores:Anotherdiagnosticpitfallforthesurgicalpathologist.Oppenheimer&Epstein(AJSP1998)

PartialAtrophy:ThemostcommonmimickerofprostatecanceronneedlebiopsyAdenosis–NeedleBiopsy16%withmorethan1focusOneofthemoredifficultdiagnosesonbiopsyDifficulttoappreciatelobulararchitectureGaudinPB,EpsteinJI.AdenosisoftheProstate:Histologicfeaturesinneedlebiopsyspecimens.(AJSP1995).

PINATYPHighgradePINwithsmallfocusofatypicalglands.Seenote:Note:AdjacenttoglandsofhighgradePINareafewsmallatypicalglands.Whilethesesmallglandsmayrepresentasmallfocusofinfiltratingcancer,wecannotexcludethattheyrepresentoutpouchingortangentialsectionsoffoftheadjacenthighgradePIN.UseofBasalCellMarkersAtypicalfavorcancer-negativestaining,confirmdiagnosisofcancerAtypicalfavorbenign-negativestaining,callatypicalBenign-negativestaining,callbenign

HedrickL,EpsteinJI.Useofkeratin903asanadjunctinthediagnosisofprostatecarcinoma.(AJSP1989).

PitfallswithBasalCellMarkersEntirelybenignglandsmaynotstainforbasalcellmarkersMorecommonlynegativestainingnon-cancerousglandsinclude:adenosis,partialatrophy,andhighgradePIN.Cancercellsmayoccasionallystainnonspecifically(notinabasalcelldistribution).Veryrarely,cancerscandemonstratebasalcellsHMWCKHMWCK/p63HMWCKp63UseofAMACRMarkerthatselectivelystainsadenocarcinomaoftheprostateandisnegativeinbenignprostateglandsAntibodytoracemase(P504s)PitfallswithAMACRFALSEPOSITIVES:LabelshighgradePINOccasionallystainsentirelybenignglandsOccasionallypartialatrophyandadenosis

PitfallswithAMACRFALSENEGATIVES:Upto20%ofsmallfociofadenocarcinomamaybenegative

Magi-GalluzziC.,LuoJ,IsaacsWB,HicksJL,DeMarzoAM,EpsteinJI.AMACR:Avariablysensitiveimmunohistochemicalmarkerforthediagnosisofsmallprostatecancerfocionneedlebiopsy.(AJSP2003).

SummaryWiththeexceptionofafewfindings,thediagnosisofadenocarcinomaoftheprostateisbasednotonanysinglefeature,butonaconstellationoffe