,,Endometrial maldifferentiation" - A clinically significant diagnosis in
Transcrição
,,Endometrial maldifferentiation" - A clinically significant diagnosis in
H .-A . S choon et al . Pferdeheilkunde15 (1999) 6 (November/Dezeml:er) 555-559 ,,Endometrialmaldifferentiation"- A clinicallysignificant diagnosisin equine reproduction? H.-4. Schoon, DorisSchoon, lsabell Wiegandt,C.-P. Baftmann. and HeikeAupperle InstitutfürVeterinärPathologie def Universität Leipzigi'Klinikfür Pferdedef Tieräztlichen Hochschule Hannover Summary The present paper describesthe functionalmorphologyof endometrialmaidifferenUation in maresaccordingto the classificationof Schoon et al. (1998).The ptimarydiagnosisis based on the investigationof routinelyH.-E. stainedslides,supplementedby immunohistological techniques (estrogenand progesterone-receptors, Ki-67 antigen,intermediatefilaments,laminin)of formalin-fixedbiopsy specimens.The morphologicalfindingsare interpretedas indicalivefor hormonaldisturbancesdue to ovarianneoplasmsand variousovariandystrophies,or as a symptom of alterationsaffecungeither the hypothalamo-pituitary-ovarian-endometrial axis or the local steroid hormone receptor status. Clinicalsymptomsare mostly absent in cases without ovarianabnormalities.No relationshipcan be identifiedbetweenendometrialmalditfe rentiationand the age or parity of the mare or season.From the authors' point of view endometrialmalditferentiation should be taken into account in the assessmentof endometrialbiopsy specimens as one important parameter leading to temporary or permanent fertility problems.In a certain case, however,the definiteprognosiswith respect to reversibilityremainsunclear,because the aetiopathogenesis has not yet been identifiedexcept for those cases of endocrineactive ovarianneoplasms.In this field an intensifiedco operationbetween cliniciansand pathologistsis necessary.Especiallysystematiccase control studies, includingendocrinologyand determinationof foaling ratesmay revealfurtherunderstandingresultingin efficientplans of treatments. Keywords: endometrium,maldifferentiation, steroidhormonereceptors,fertilitydisorders,horse ,,EndometrialeFehldifferenzierung"- Eine klinisch relevante Diagnose in der equinen Reproduktionsmedizin? Entsprechendder Einteilungvon Schoon et al. (1998)wlrd die funktionellelvlorphologieeiner endometrialenFehldifferenzierung unter dem (UED)"und einer ,,irregulären (lED)"beschrieben. Bild einer ,,ungleichmäßigen endometrialenDitferenzierung endometnalenDifferenzierung Die primäreDiagnosebasien auf der Untersuchungvon H. E.-gefärbtenhistologischenSchnitten,sie wkd ergänztund präzisiertdurch immunhistologischeTechnikenam formalinfrxierten Biopsiematerial(Oslrogen-,Progesteronrezeptorstatus, Expressionvon Ki-67 Antigen, Nachweisvon Intermediärfilamenten und Laminin).Die histopathologischen Befundewerden,je nach Lage des Falles,als Hinweisfür hormondle lmbalancenbei Ovartumoren,eine ovarielleDystrophie,eine Störungdes HypothalamusHypohysenOvar-Endometrium-Regelkreises bzw. als AusdruckeinerlokaienStörungdes endometrialenSteroidhormonrezeptorstatus interpretiert.HinweisendeklinischeSymptome mit AusnahmederjenigenStuten,die an klinischmanifestenStörungender Ovarfunktionleiden,fehlenzumeist.Ein Zusammenhangkonnte weder zum Alter der Patientinnennoch zum Reproduktionsstatus, der Paritätoder der Jahreszeithergestelltwerden. DieAutorenhalteneine Berücksichtigungdes Befundes für dringenderforderlich, bei der Beudeilungvon Endometriumbiopsien 'endometrialeFehldifferenzierung" da diesesErscheinungsbild nach eigenenErfahrungenmit vorübergehenden oder permanentenFertilitätsproblomen einhergeht.Die Ursache kann, mit Ausnahmedes VorliegensendokrinaktiverOvartumoren,dezeit im Einzelfallnoch nicht sicher ermitteltwerden. Hierzubedarf es einer intensivenKooperationKlinik-Pathologie, insbesonderedurch gezielteVerlaufsuntersuchungen unter Einbeziehungder Endokrinologie sowie der Abfohlergebnisse, um zukünftigeinendem EinzelfallangemessenenTherapieplanentwickelnzu können. Schlüsselwörter: Pferd Endometrium,Fehldifferenzierung, Steroidhormonrezeptoren, Fertilitätsstörungen, Introduction For years it has been well-established in numerousreports that endometritisand endometrosisare imoortantcauses for fertilityproblems in the mare. Functionaldisturbances however,have so far playeda minor role in equinediagnostics and research.In human gynaecopathology such alterationsare well known as possiblecauses of infertility.Ovarian dysfunctions and tumours, central defects, hormone refractiveendometria and hormonal treatments result in greatlyvaryingbut ,,specific"morphologicalchangesin human beings (Dallenbach-Hellweg,1987). Duringseasonalequine ovulatorycycles,the endometrium proliferatesand differentiatesin response to physiologic changes in estrogen and progesteronelevels(Brunckhorst et al., 1991).lt reacts immediatelyto hormonalcyclicalvariationsas well as to disturbances(Schoonet al., 1999)and hormonaltreatment(Kluget al., 1997). Pferdeheilkunde 15 In this way the endometrialbiopsy servesas a distinctbiothe hormonesat the tissue level.Thereassay,,measuring" fore the estimationof the endometrialstage -"dating the endometrium" and the determination of endometrial differentiation as physiologicalor as pathologicalmust be the first steps in the investigationof each biopsy sample (Schoonet al., 1999). Methods In routine biopsy examinationendometrialmaldifferentiations are detectableby means of histopathology(HE, PASalcian-blue,Picro-SiriusRed stain). Additional investigametions usingnewlyestablishedimmunohistopathological thods, i ,e. i ntermedi ate fi l aments(vi menti n,desmin) ,lam i- 555 - A clinically Maldifferentiation" significant diagnosisin equinereproduction? ,,Endometrial nin, estrogen(ER)and progesteronereceptors(PR)and the proliferation marker Ki-67 antigen (Ozgen et al., 1997; Schoon et al., 1997; Schoon et al., 1998; Aupperle et al., 1999) are additionallyhelpful.These techniquesare applicable to specimensfixed in neutral,bufferedformalin,even in routinediagnostics.Bouin-fixative however,recommended for years(Schoonet al., 1992)whilstprovidingsuperior ce l l u l ardet ailslim it st h e p o s s i b i l i ti eos f i m m u n o h i stol ogy. Thereforeit should be avoided even for routinediaqnostic purposes. Classification According to Schoon et al. (1999)two major featuresof endometrialmaldifferentiation exist based on findingsin H,-E.stainedslides:unequaland irregularendometrialdifferentiation. Endometrialmaldifferentiations as describedhere are exclusivelythose which occur in endometrialareaswithout fibrosis, any periglandular In cases of unequaldifferentiation in one biopsysampletwo functionalstagesare obvious:areasdifferentiated in accordance with the stage of the ovariancycle and multiplenon fibroticfoci of glands deviatedeitherin degreeor qualityof pattern. activityfrom the dominantphysiological tria (Aupperle, 1997), The ER and PR reactivityof the unaffected glands resemblestypical findings of the normal proliferationphase. In many glands the lamininlabellingof the basal lamina is remarkablv low and often disconti nuous. The irregular differentiationis characterised by a diffuse glandularalterationaffecting all or at least most of the glands within a specimen.Abnormalproliferative or secretory activitymay be present, in other cases patterns occur which cannot be appointedto any kind of physiological differentiation.Correspondingsubdivisionswere made based on the dominatingsigns of endometrialfunctionalmorphology. The most obvioussign of irregularproliferative differentiation is the distinct polymorphismof the glandularepithelia. Within a single gland longish,oval and round, hyperchromatic and hypochromaticnuclei occur in basal, mid and apical positions(Fig. 1). Their lininghas lost its orderlyarrangement.Glands with hyperplasticepitheliaand numerous mitosesmay be present. The epithelialexpressionof Ki-67 antigen is very intense and correspondswith high valuesof estrogenreceptorsof the glands and low levelsin the stromalcells (Fig.2). The expressionof the progesteronereceptor is pathologically low. *s# ': f*, *t,q' 4..q Fig.1: lrregularproliferative Poly- Fig 2: endometrial differentiation. morphicglandular epithelia showlongishor oval,mostly hyperchromatic nucleiin basal,mid or apicalpositions mitoses. H.-E.stain,magnification andnumerous 3O0x lrregulärproliferative Differenzierung. Die endometriale Drüsenepithelien sind polymorphmit länglichen oder ovalen,meisthyperchromatischen Zellkernen in basaler, mittlerer H.-E.Färbuno. oder aoikalerPosition. Gerätevergrößerung 300x Frequentlythese glands are closelyapposed forming non fibrotic nests, lacking distinct borders to the adjacenttissue. Epitheliaas well as stromal cells express high values however,an intense of estrogenreceptors.Physiologically expressionin the epitheliais correlatedwith a weak stromal reaction and vice versa (Aupperleet al., 1999).The labellingof the proliferationmarker Ki-67 antigenis unusually low. The stromal cells show an unphysiological expression of desmin. lt is reportedthat desmin-positivestromal cells occur in mares with pathologicallyinactiveendome- 556 lrregular proliferative endometrial differentiation. The epithelialexpressionof ER is rather uniform and high, stromalcellsshow a weak expression.lmmunohistology, estrogen receptor expression, Nomarski-interferencecontrast,magnification 62.5x lrregulär proliferative endometriale Differenzierung. Während die Eoithelzelleneine hohe Exoressionvon Östrogenrezeptorenzeigen, reagierendie Stromazellen nur schwach positiv. lmmunhistologie,Östrogenrezeptornachweis, Nomarski InterJerenzKontrast. Gerätevergrößerung62,5x In cases of an irregular secretory differentiation, large and highly secretory glands dominate, The glandular epithelia are of enormous height, the pale cytoplasm contains numerous vacuoles. Large, round and hypochromatic nuclei are intermingled with depolarised nuclei of various shape and chromatin density (Fig. 3). Although a secretory morphology is obvious, an intense epithelial estrogen receptor expression and proliferationactivity is present (Fig, a). P ferdehei l k unde' 15 - A clinically Maldifferentiation" diagnosisin equinereproduction? significant ,,Endometrial tiology in a certain case (Dallenbach-Hellweg,1987),comparableinvestigations are lackingin the horse,There is little informationabout endometrialdifferentiation disorders.Endometrial atrophy during the late physiologicalbreeding Tab.1: Histopathological type of endometrial maldifferentiationseason as a result of hormonal refractive endometrium (Schoonet al., 1997) and endometrialhypoplasiaand hyoccurringspontaneously or in the courseof ovariandiperplasiaare repofted (Ricketts,1975; Kenney, 1978).Thus SEASES. these descriptionsdo not correspondwith the phenomena Histopathologische Charakterisierung der endometrialen of unequalor irregularendometrialdifferentiation as defined Fehldifferenzierung bei Spontanfällenund im VerlaufovariellerErkrankunoen. here. Focal hypertrophyand atrophy occur in glands affected by endometroticlesions(Kenney, 1978; Schoon et al., Morp h o l o g i c a l 3pontaneous Ovarian Ovarian 1997).These glands are known to undergo processesof classification cases neoplasms dystrophy maldifferentiation as well, however,due to other pathome(n) (n) (n) (Aupperle chanisms et al., 1997). It is supposedthat diffuseirregularendometrialmaldifferenNormalendometrial tiationsare resultsof hormonaldisturbancesincludingthose differentiation 2 resultingfrom hormonallyactiveovarianneoplasmsand dystrophy as described in women (Dallenbach-Hellweg, Unequalendometrial 1987).In cases of unequaldifferentiation a partialhormone differentiation(UED) 11 refractiveendometriumis more likely(Fig.6). rentiationdid not occur. The teratoma and the benign serous cystadenoma did not affect the endometrialdifferentiation,Differenttypes of non tumoroussovariandystrophies(Tab.1) resultin variousfeaturesof IEDtoo. lrregularendometrial differentiation(lED) (partially) hormonerefractive - proliferative '13 - secrercry 19 - comptetety irregutitr 11 z 1 endometrial maldifferentiation 5 n I i rreg u l ar endometri al d i ff ere nt i ati on IE D In the cases where a second biopsy after ovariectomywas availableafter2 to 5 weeks (n=10)a distincttendencyto a more regularendometrialdifferentiation was obvious,interpreted as indicativefor a possiblereversibility of these hormonallymediatedalterationsof functionalendometrialmorp h o l o gy . -t ortemporary I permanent i problems fertility I I Fig. 6: C l i n i c als ignif ic anc e Equine endometrialfunctionaldisturbancesare first described by our group as a phenomenonoccurringspontaneously(Schoonet al., 1998)or in the course of hormonal active ovarian neoplasms(BarTmannet al., 1998).The diagnosis is possible by the investigationof routinelyH.-E.stained slides and confirmed by immunohistological methods, In all cases investigated at leastone and mostlyall of parametersdiffer from normal exthe immunohistological pressionpatterns. The endometrialdifferentiation is a highlysensitiveindicator of the hypothalamo-pituitary-ovarian-endometrial axis, A physiological equine estrouscycle resultsin a uniformand synchronousfunctional morphology of the endometrium (Brunckhorstet al., 1991;Strankmeyer, 1993; Raila et al., 1997) Disordersmay lead to permanentor temporarysubfertilitypossiblydue to an altereduterineenvironment,e.g, in a disturbed uterine secretory protein pattern as described in endometrosis(Baderet al., 1997).Whilethese alterationshave been well known in human gynecopathology for years and describedin detail indicatinga ,,specific"ae- 558 hormonal disturbances Causes and featuresof endometrialmaldifferentiation. Ursachenund Erscheinungsformen Fehlendometrialer differenzierunqen. No conclusivestatementregardingthe aetiopathogenesis can be made in cases where ovarian disorders have been excluded.The conditionis relatedneitherto age nor to parity of the mare nor to the annual season. Most of the mares have been barren for one or severalyears,The latter fact indeedindicatesthat endometrialmaldifferentiation is a diagnosisof clinicalimportancewhich shouldbe includedin the assessmentof endometrialbiopsy diagnosis.More detailed case control studies includingthe estimationof the endocrinestatus are necessaryfor the understandingand prognosticassessmentof this lesion.The aim of our current work is to correlate classicalhistopothologicalmethods, immunohistopathology and clinicalsymptoms including endocrinologyto infer a causal therapeuticconcept from a certainfeatureof endometrialmaldifferentiation. Literature Aupperle, H. (1997): lmmunhistologische Untersuchungen amEndomeVeterinärmedizinische Fakultät, triumderStute.Leipzig, Disserlation Pferdeheilkunde 15 H.-4. Schoonet al. Aupperle, H., H.-A. Schoon, S. Özgen, E. Ktug and C.P. BarTmann (1997):lmmunohistological methodsfor the characlerization of physiologicaland pathologrcal functions.Pferdeheilkunde endometrial 13,551 Aupperle,H., S. Özgen,H.-A. Schoon, D. Schoon,H.-O. Hoppen, H. Sieme and A. Tannapfel(1999):Cyclicalendometrialsteroid hormone receptorexpressionand proliferationintensityin the mare. Equinevet.J, in press Bader, H., H. Kremer, C. Vogt, H.-A. Schoon and K. Beier-Hellwig (1997)lnvestigations of the proteinpatternsof the equineuterine secretionsas functionalparameterof the endometrium.Pferdeheilkund e1 3,5 44 Bartmann, C.P., L Brickwedel, B. Frühauf, M. Wachholz, H.-A. Schoon and E. Klug (1998):Ovartumorbei der Stute - Diagnose und chirurgische Behandlung. DVG-Tagungsbericht, 15. Arbeitstagung,,Fachgruppe Pferdekrankheiten", Wiesbaden Brunckhorst,D., H.-4. Schoon,H. Bader and H. Sieme(1991):Morphologische,enzym- und immunhistochemische Charakteristika des endometrialen Zyklusder Stute.Fertilität 7, 44-51 Dallenbach-Hellweg, G. (19BZ):Functionalendogenous(hormonal) disturbances. In Histopathology of the Endometrium. G. DallenbachHellweg.Springer-Verlag, Berlin,96-158 Kenney,R.M. (1978):Cyclicand pathologicchangesof the mare endometriumas detectedby biopsy,with a note on earlyembryonic death .J. Am. Ve t.Me d.As s oc .172, 241- 262 Klug, E., C.P. Bartmann,A. Schöning,D. Schoon and H.-A. Schoon (1997):Auswirkungen einer Progestagen-Langzeit-Applikation auf Sexualzyklusund Endometriumdes Pferdes- Zwd Seiten einer -. Pferdeheilkunde therapeutischen Medaille 13, 490-498 OzgenS., K. Fasch, G. Kropp, H.-A. Schoon, H. Aupperle,H. Sieme and E. Klug (1997):Aetiopathogenesis and therapyof equinehydromucometra:Preliminary Data.Pferdeheilkunde 13, 533-536 Raila,G., H.-A. Schoon, D. Schoon, S. Özgen,H. Aupperle,E. Klug and O. Strankmeyer(1997):The equineendometrialcycle:a morphometrical,ultrastructural, enzyme-and immunohistological investigation. Ann. Meet.Am. Soc. Anim.Sci.,Nashville Tennessee, J. A nim .Sci.7 5, Su pp l.1 Ricketts,S.l//. (1975):Endometrialbiopsyas a guideto dragnosisof endometrialpathologyin the mare. J. Reprod.Fertil,Suppl.23, 341-345 Pferdeheilkunde 15 Schoon, H.-A., D. Schoon and E. Klug (1992):Uterusbiopsienals Hilfsmittelfür Diagnoseund Prognosevon Fertilitätsstörungen der Stute.Pferdeheilkunde B, 355-362 SchoonH.-A.,D. Schoonand E. Klug (1997):Die Endometriumbiopsie bei der Stute im klinisch-gynäkologischen Kontext.Pferdeheilkunde13,453-464 Schoon, H.-A., L Wiegandt,D. Schoon, H. Aupperle and C.P. Bartmann (1998):Functional disturbances of the equineendometrium., Proc.7th Int.Symp.Equ.Repr.,Pretoria12-17July98, 103-104 Schoon, H.-A., l. Wiegandt,D. Schoon, H. Aupperle and C.P. Bartmann (1999):Functional disturbances of the equineendometrium. J. Reorod.Fertil. Strankmeyer, am EndoO. (1993):Morphometrische Untersuchungen metriumzyklischerund ovariektomierter, hormonbehandelter Stuten. Hannover,Tierärztliche Hochschule,Dissertation Prof. Dr. H.-A. Schoon Dr. Doris Schoon lsabellWiegandt Dr. HeikeAupperle In stitut für Veterinär-Pathologie An den Tierkliniken33 04301 Leipzig Tel.0341/9738270 Fax. 0341/9738299 [email protected] Dr. Claus Peter Barlmann Klinik für Pferde Tierärztliche Hoch schule Hannover BischofsholerDamm 15 D-30173 Hannover Tel.:0511-8567233 Fax:0511-8567688 559