Purpose: We determined age-related differences in prostate internal architecture and prostate volume by transrectal ultrasonography in Japanese men 40 to 79 years old.
Materials and methods: The 287 study participants were categorized by transition zone disease: group 1-not visible (normal prostate), group 2-visible, borders unclear (diffusely enlarged hyperplasia) and group 3-visible, border clear (nodularly enlarged hyperplasia).
Results: Group 1 comprised 40% of men 50 to 79 years old and showed slightly decreased median prostate volume with age. Prostate volume and its variance increased with age in group 3 but differed little across age in group 2.
Conclusions: In a community sample the prostatic internal architecture relationship with age and prostate volume suggested differing growth patterns.