Unilateral anorchism. Report of 11 cases with discussion of etiology and pathogenesis.

Eleven cases of unilateral anorchism are presented. The patients, aged two to thirty-nine years, were explored for cryptorchism but, though ducts could be identified operatively in most cases, there was doubt regarding the presence of the testis. These tissues, including the putative testes, were excised and pathologically the excurrent ducts, consisting of vas deferens with or without epididymis, were seen in all cases. No tunica albuginea or testicular parenchyma was identified and the structures, submitted as possibly testicular, were nonencapsulated, well-circumscribed, subserosal foci of highly vascularized fibrous tissue with few small nerves and smooth muscle bundles. Dystrophic calcific deposits were seen in 2 cases and microfoci of poorly developed Leydig cells in 2 cases. A vascular hypothesis is proposed for the etiology and pathogenesis of unilateral anorchism.