Structural heterogenity of intraluminal content of the prostate: a histochemical and ultrastructural study.

Intraluminal contents of benign and malignant prostatic tissue are associated with varying forms of acellular structures. These include corpora amylacea, prostatic calculi, and prostatic crystalloids. There are relatively few microscopy studies about the characterization of intraluminal structures from benign and malignant prostatic glands and little is known about their chemical composition. In the present study, we used a combination of special histochemical methods, immunohistochemistry, and transmission electron microscopy to characterize intraluminal contents of benign and malignant prostate glands. The study was done on 33 radical prostatectomy and four transurethral resections of prostate specimens. Histochemical methods such as von Kossa, autometallography (AMG), as well as PSA immunohistochemistry and transmission electron microscopy were performed to characterize intraluminal contents of benign and malignant prostate glands. Von Kossa staining was observed in acellular structures, corpora amylacea, prostatic calculi, and calcified blood vessels. AMG staining was observed in the lumen of small glands, in the epithelium lining prostate glands, and corpora amylacea. PSA staining showed prostatic glands with both positive and negative corpora amylacea and epithelial cells. Ultrastructural observation revealed the presence of a variety of highly heterogeneous aggregates composed of fibrillar elements that were similar to those of amyloid.