Localized amyloidosis of the lower genitourinary tract: a clinicopathological and immunohistochemical study of nine cases.

A series of nine cases of localized amyloidosis of the lower genitourinary tract are reported. The patients comprised six males and three females with an age range of 50-79 years at initial presentation. Clinically and on cystoscopy, the lesions were often diagnosed as neoplasms. Histologically, seven cases had typical features of localized amyloid deposits, while two cases had an unusual appearance with a florid histiocytic and giant cell reaction. Using an immunoperoxidase staining method the deposits were non-reactive with antibodies to serum amyloid A protein, prealbumin and beta 2 microglobulin, while equivocal immunoreactivity was seen with anti-light chain antibodies.