Midline Cysts in the Prostate: Incidence in Healthy Men on Transrectal Ultrasonography (TRUS)

Lee, Eun Kyoung; Kim, Sun Ho; Lee, Yong Seok

Abstract

PURPOSE
To describe the incidence of prostatic midline cysts in healthy men on transrectal ultrasonography.
MATERIALS AND METHODS
From 2005 to 2009, 1,175 transrectal ultrasonography examinations were performed on 1,086 men (22-85 years) in a health promotion center. Incidence and size of midline cysts in men without any symptoms in the genitourinary tract were investigated according to age, prostate volume, and other ultrasonography findings.
RESULTS
The incidence of midline cysts in healthy men was 28% (280/999). The mean diameter of midline cysts was 7.2 mm (1-30 mm). The incidence was the highest (32/102; 31.4%) and the size was the smallest (6.2 mm in mean) in men older than 60 years. The incidence of midline cysts in prostates larger than 20 ml was 33.2% (157/473) and in prostates smaller than or equal to 20 ml was 23.4% (123/526) (p < 0.05). Abnormal ultrasonography findings other than midline cysts were found in 196 men, and the incidence of midline cysts was high with seminal vesicle abnormalities (5/11; 45.5%).
CONCLUSION
The incidence of prostatic midline cysts in healthy men on transrectal ultrasonography is higher than the result of previous studies. The incidence is higher in an enlarged prostate than in a prostate of normal size.