Differential diagnosis of trichoblastoma and basal cell carcinoma in skin

WU Xue-mei; WANG Xiao-ming; GUO Shao-feng; YAN Hao; YU Meng-yi; XIAO Liu

doi:10.3969/j.issn.1007-8096.2018.03.009

Abstract：Objective To explore the morphological features,immunohistochemical phenotype and differential diagnosis of the trichoblastoma and basal cell carcinoma in skin.Methods A total of 6 cases of trichoblastoma and 20 cases of basal cell carcinoma weres studies by using HE staining and immunohistochemical staining on CK7,Bcl-2,AR,CD10,Ki67.The expression of morphological features and immunohistochemical phenotype were observed in tumor cells.Results Trichoblastoma was from the basal germinal cells.Tumor was located in the dermis and subcutaneous tissues,not connected to the skin,clearly bounded by uniform distribution of trichoblastic cells with follicular differentiation.CK7 was weakly positive in 1 case and negative in 5 cases.bcl-2 was weakly positive in 3 cases and negative in 3 cases.AR was negative in 6 cases.6 cases of trichoblastoma were positive for CD10 in tumor stroma and negative in tumor cells.The rate of Ki67 was about 10％～ 20％.Basal cell carcinoma was from the basal germinal cells.Tumor was connected to the skin,grown in an invasive way.The surrounding cancer cells were arranged in a fence.It was loosened in surrounding stroma and formed of lkhrinkage crack in between tumor cells and tumor stroma.CK7 was weakly positive in 6 cases and positive in 14 cases.Bcl-2 was weakly positive in 3 cases and positive in 17 cases.AR was weakly positive in 4 cases and positive in 16 cases.CD10 were positive in tumor cells and negative in tumor stroma.The rate of Ki67 was about 20％～ 30％.Conclusion The differential diagnosis between two types of tumors is helped by the combination of histological characteristics and immunohistochemical phenotype.