Intratubular Germ Cell Neoplasia
Intratubular germ cell neoplasia (IGCN) with microinvasion. The interstitium shows scattered clusters of atypical germ cells (lower right corner) morphologically similar to those seen in the tubules. The tubular basement membrane is thickened. The interstitium also contains clusters of Leydig cells. The appearance of intratubular germ cell neoplasia (IGCN) is same regardless of the type of invasive germ cell tumor present in the testis. The incidence of IGCN is lower for mature teratoma. It is also uncommon with pure yolk sac tumors and germ cell tumors occurring in prepubertal testis.