Tubules may contain only Sertoli cells and no spermatogonia.
Tubular sclerosis and thickened hyalinized basement membranes are present.
Relative Leydig cell "hyperplasia" – look more numerous because the rest of testis is atrophic.
Hypoplastic rete testis.
May have "pick adenoma" or Sertoli cell nodule.
Precursor intratubular germ cell neoplasia (ITGCN) may be present.
Increase risk of testicular cancer (5-10X, especially germ cell neoplasms, most commonly seminoma) and infertility.