Penile myointimoma: a clinicopathologic study
ZHANG Jiao-jiao
YANG Zhe
ZHANG Guan-jun
GONG Hui-lin
Abstract：Objective To evaluate the clinicopathological features,immune phenotype,differential diagnosis and prognosis of penile myointimoma.Methods A case of penile myointimoma was analyzed by clinicopathological observation,immunohistochemistry and literature review.Results A male patient of 13-year-old presented with a 1 month history of a nodular mass involving the glans penis and the size of the tumor was 0.8 cm × 0.5 cm × 0.5 cm.Histologic examination revealed occlusive myointimal proliferation with a complex multinodular/plexiform architecture involving the preexisting vasculature of the corpus spongiosum.The neoplasm was composed of sheets of spindled and stellate-shaped cells with long tapered or fibriform eosinophilic cytoplasmic processes embedded in fibromyxoid matrix.No significant nuclear atypia was present,and no mitotic figures were identified.The native smooth muscle of the vascular walls surrounded the lesion and some vascular lumens were still visible.Immunohistochemical staining showed that the myointimal cells were positive for vimentin,SMA,actin and calponin but negative for S100,CD34,CD31,CD68,CK and EMA.Desmin showed negative in the lesional cells,but highlighted the native residual smooth muscle cells in the vascular walls confirming the intravascular proliferation.In addition,the Ki67 positive rate was less than 1％.Conclusion Penile myointimoma is a rare,benign mesenchymal tumor derived from the intimal cells of blood vessels in the corpus spongiosum of the penis.The main importance of recognizing myointimoma is to distinguish it from more clinically aggressive histologic mimic neoplasms.
Keywords：Penile myointimomaClinicopathologyDifferential diagnosis
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 594-597 )