Malian raphe cyst of the penis - A report of two cases with immunohistochemical investigation

Penile median raphe cysts are uncommon benign lesions occurring predominant ly in the ventral aspect of the glans penis of young men. We observed two c ases: those of a 67-year-old patient and a 22-year-old patient. The epithel ial lining of the cysts Was composed of pluristratified small cells that fo cally showed rows of columnar cells above the inner surface as well as a mo nolayered mucincius columnar epithelium. A columnar cell lining predominate d in the younger patient. The cytokeratin (CK) immunostaining pattern of th e two cysts (CK7(+++), CK13(+++), CK20(-), CAM 5.2(+)) supports the interpr etation of a columnar mucinous epithelium undergoing immature urothelial me taplasia. Carcinoembryonic antigen immunostaining positivity of the columna r cells is probably related to the dysembryogenetic cloacal nature of the c ysts. Neuroendocrine differentiation of sparse cells interspersed in the pl uristratified epithelium was documented by immunohistochemical staining for chromogranin and synaptophysin. Cilia were not identified in the columnar cells by light microscopy or by antidynein immunohistochemistry.