Amyloidosis of seminal vesicles and ejaculatory ducts: a histologic analysis of 21 cases among 447 prostatectomy specimens.

To investigate the incidence of amyloidosis of seminal vesicles and ejaculatory system including ejaculatory ducts and vasa deferentia, we reviewed the whole mount sections of 447 radical prostatectomy specimens removed for prostatic cancer, including 273 cases from the United States and 174 cases from Korea. Of these, 21 cases (4.7%) showed amyloidosis in seminal vesicles, vasa deferentia, and in ejaculatory ducts. Ten of these (3.7%) cases were from the United States and 11 cases (6.3%) from Korea. The patients' age ranged from 51 to 79 years (mean, 66.1 years). Amyloid deposition was found in 5 patients in the sixth decade (3.4%), 9 patients in the seventh decade (4.7%), and 7 patients in the eighth decade (9.3%). At the seventh decade of life, the Korean patients showed a higher incidence (8.3%) than American patients (2.5%), but other age groups showed no difference. All cases showed bilateral involvement of the seminal vesicles and ejaculatory systems. The deposits of amyloid tended to be nodular and affected the subepithelial region of seminal vesicles, vasa deferentia, and ejaculatory ducts. There was no amyloid deposit around blood vessels or in the prostatic parenchyma. Localized amyloidosis of the ejaculatory system involves not only the seminal vesicles but also the vasa deferentia and the ejaculatory ducts. The vessels or prostatic stroma are not part of this process. Amyloidosis develops subepithelially spreading to include the wall of these organs and appears to be related to advanced age. The incidence of amyloidosis of the ejaculatory system in Korean patients was higher than in US patients.