Nonspecific peritesticular fibrosis manifested as testicular enlargement.

Nine cases of peritesticular fibrosis initially appeared to be enlargement of the testes. Seven patients under went orchiectomy and two had biopsy specimens taken of the grossly thickened tunica albuginea. In six patients, a hydrocele was present with intramural fibrosis and minimal chronic inflammation. Active epididymitis and chronic interstitial orchitis were present in two patients, with some spread of the inflammation into the fibrotic peritesticular tissues. One case, without associated hydrocele or epididymitis, showed dense fibrosis of the peritesticular tissues with focal edema, lymphangiectasis, and minimal perivascular round cell infiltration. This clinicopathological entity of diffuse peritesticular fibrosis is an unrecognized cause of benign testicular enlargement. The hypothesis is advanced that the primary process is a congenital hypoplasia of the peritesticular lymphatics progressing at various speeds into a state of chronic lymphedema and end stage noninflammatory fibrosis.