www.ksmf.org/arhimed   arhimed@ksmf.org   [5/10/2025 8:55:17 AM] http://www.ksmf.org/arhimed/poglej.asp?id=78 Diagnosticni pomen imunohistokemicne diferenciacije hepatoblastomov Avtor: Lena Perger Mentor: prof.dr. Vera Ferlan-Marolt, dr.med. Hepatoblastom je maligni tumor jeter pri otrocih. Patohistološke znacilnosti te zanimive novotvorbe so zelo heterogene zaradi številnih možnosti diferenciacije celic v tumorski rasti. Vzroki sposobnosti tumorskih celic, da se lahko razvijejo v najrazlicnješe vrste bolj ali manj zrelih tkiv, zaenkrat še niso povsem razjasnjeni. Možen vzrok bi lahko bil izvor tumorja iz ene nediferencirane celice ali pa metaplasticna in neoplasticna preobrazba razlicnih vrst celic. Ker izvorne celice, iz katere se ta tumor razvije, še niso uspeli opredeliti, ostajajo zaenkrat tudi vprašanja glede histogeneze hepatoblastoma še nerešena. Namen raziskave je bil, da podrobno proucim in opišem histomorfološke in imunohistokemijske znacilnosti hepatoblastomov v slovenski populaciji in v patomorfološki diagnostiki uporabim novo razvito protitelo hepatocitni parafin 1, ki specificno oznacuje celice hepatocitne diferenciacije. Iz rezultatov sem nameravala ugotoviti, kateri imunohistokemijski oznacevalci so najbolj zanesljivi pri diagnostiki tovrstnih tumorjev in sklepati o njihovi histogenezi. Predvidevala sem, da bom v proucevanih tumorjih zasledila zelo pestre histološke razlicice hepatoblastoma, da se bodo alfa-fetoprotein, karcinoembrionski antigen in hepatocitni parafin 1 izkazali za dobre oznacevalce teh tumorjev, in da bodo rezultati naloge potrdili domnevo o nastanku hepatoblastoma iz pluripotentne nediferencirane celice. V proucevanih tumorjih sem opazovala epitelijsko razlicico s fetalnimi in embrionalnimi hepatociti, mešani hepatoblastom z nezrelim vezivnim tkivom in podrocji rahle miksomatozne strome ter drobnocelicni anaplasticni hepatoblastom. Alfa-fetoprotein, karcinoembrionski antigen in hepatocitni parafin 1 so v veliki meri obarvali samo bolj diferencirane tumorje, pri slabše diferenciranih je bil obcutljivejši vimentin. Hepatocitni parafin 1 se je izkazal za zelo specificnega oznacevalca celic jetrnega parenhima in lahko v prihodnosti postane pomemben na podrocju patohistološke diagnostike bolezni jeter. Ob socasnem izražanju vimentina in citokeratinov v celicah hepatoblastoma sem razmišljala o možnem izvoru iz entodermalne, nizko diferencirane celice. «» [Abstract / English version] The role of immunohistochemical differentiation in the diagnosis of hepatoblastoma Author: Lena Perger Mentor: prof.dr. Vera Ferlan-Marolt, dr.med. Hepatoblastoma is a malignant tumor of children. It is characterized by very heterogeneus histopathology due to almost all kinds of cell differentiation that can be found in such tumors. Exact reasons for the great potential of differentiation exhibited by hepatoblastoma are not determined yet. Among the possible reasons one could be a poorly differentiated stem cell from which the tumor developes, another one is metaplastic and neoplastic transformation of multiple cell lines. The histogenesis of hepatoblastoma remains to be elucidated and the nature of its stem cell to be discovered. The aim of this investigation was to study the histopathological and immunohistochemical properties of hepatoblastomas in Slovenian population and to use a newly discovered antibody Hepatocyte Paraffin 1 which is highly specific for parenchymal liver cells. From the results, I intended to evaluate the most useful immunohistochemical markers for the diagnosis of hepatoblastoma and to contemplate upon the histogenesis of this neoplasm. I assumed to find a great variety of histological patterns in the tumors included in the study. My expectations were that alpha-fetoprotein, carcinoembryonic antigen and hepatocyte paraffin 1 will prove to be useful markers for hepatoblastoma and that my findings will support the hypothesis of pluripotent undifferentiated cell being the stem cell of this liver tumor. Epithelial hepatoblastomas comprising fetal and embrional hepatocytes, a mixed tumor with areas of immature connective tissue and loose myxomatous stroma, and a small cell anaplastic variant of hepatoblastoma were all represented in tissue samples chosen for the study. Alpha-fetoprotein, carcinoembryonic antigen and hepatocyte paraffin 1 were positive in the majority of well differentiated tumors. However, vimentin proved to be more sensitive in the less differentiated cases. Hepatocyte paraffin 1 is a very specific marker for cells of liver parenchyma and has a great perspective in pathohistologic diagnosis of liver disease. Simultaneous expression of vimentin and cytokeratins in the cells of studied tumors suggests that an uncommitted entodermal cell could be a progenitor of hepatoblastoma.