Comparative Study of CD105 and Ki-67 in Adenoid Cystic Carcinoma and Polymorphous Low Grade Adenocarcinoma of the SalivaryGlands

Abstract

Background: The intersecting clinicopathological features and histological patterns, including cribriform, tubular and solid patterns of adenoid cystic carcinoma (ACC) and polymorphous low-grade adenocarcinoma (PLGA) may end in a problematic diagnosis .ACC has a worse prognosis than PLGA making distinction important for therapeutic and prognostic purposes . TheAimsofthisstudyweretoevaluatetheimmunohistochemical expressionofCD105 and Ki-67in adenoidcysticcarcinomaand polymorphous low grade adeoncarcinoma ofthesalivaryglandsandtocorrelatetheimmunoexpressionof these proteinswiththeclinicopathologicalfindings.MaterialsandmethodsIn this retrospective study ,fifty ofarchivalformalinfixed paraffinembeddedtissuesamplesofsalivary gland malignancies were used, twenty five blocksof adenoidcysticcarcinomas andtwenty five blocksof polymorphous low grade adenocarcinomaobtainedfromthearchivesofthedepartmentoforalpathology/ collegeofdentistry/Baghdaduniversity,Al-ShaheedGhazihospital,wereincluded in ourstudy.Four micrometer sectionsgainedandimmunostainedusingmonoclonalantibodyagainstCD105 and Ki-67.Theimmunoexpression was identifiedbythepresenceofbrownstaininthe cytoplasmoftumorcell in CD105 and thepresenceofbrownstaininthe nucleus oftumorcell in Ki-67.Theproportionofcellsthatexpressedthestain wascorrelatedwiththeclinicopathologicaldataof thepatients.Results:CD105 expressionwasfoundpositivein21casesofACCand 20cases of PLGAlocalizedintumorcells. andKi-67 expressionwasfoundpositivein24casesofACCand 23 casesof PLGAlocalizedintumorcells.Non- significant statistical relation (P=0.801) was detected regarding CD105 expression in both types of tumor and non- significant statistical relation (P= 0.852) was detected regarding Ki-67 expression in both types of tumor . Non- significant statistical relation (P= 0.05) was detected regarding CD105 and Ki-67 expression in relation to sex, site and stage in both types of tumor.Conclusion:Weak expressionCD105 and Ki-67 in ACC and PLGA mightbeexplainedby CD105 and Ki-67 did notrepresentan exclusivefactorsconsequently;otherfactorsmightbeinvolvedin theproliferation,progressionand metastasisofboth tumortypes.