Morphologic and biologic studies on ten cases of verrucous carcinoma of the vulva supporting the theory of a discrete clinico-pathologic entity

Abstract. Gualco M, Bonin S, Foglia G, Fulchieri E, Odicino F,Prefumo F, Stanta G, Ragni N. Morphologic and biologic studies on tencases of verrucous carcinoma of the vulva supporting the theory of adiscrete clinicopathologic entity. Int J Gynecol Cancer 2003;13:317—324.Ten cases of verrucous carcinoma (VC) of the vulva diagnosed fromJanuary 1989 to December 1996 were studied. Patient age ranged from50 to 83 years. The following examinations were performed on bufferedformalin-fixed material: 1) in situ DNA hybridization, probes HPV 6/11,16/18, 31/35/51; and 2) a series of immunohistochemical stainings todemonstrate wild and mutant types of the p53 protein, cytokeratinexpression and pattern distribution (AE1 and AE3), and proliferatingpattern(MIB1).InsituDNAhybridizationanalysisforhumanpapilloma-virus 6/11, 16/18, 31/35/51 was negative in all cases. Wild and mutanttypes of p53 protein transcribed from related oncosuppressor gene werenot detected. Keratins AE1 and AE3 showed a peculiar distributionpattern, that is, AE1 was uniformly positive in the surface andintermediate layers, while it was almost negative in the basal layerwhich–on the contrary–was mainly positive to AE3 keratins. MIB-1highlighted 10—40% of proliferating cells; however, in all cases, 70—80%of MIB-1 positivity was found in the basal layer of the neoplasticepithelium. These results seem to show the morphofunctional andgrowth characteristics of neoplastic epithelium, thus stressing that VCshould be considered as a discrete entity in vulvar tumors.