Revisiting the central gland anatomy via MRI: Does the central gland extend below the level of verumontanum?

Abstract

To determine whether the central gland of the prostate, composed of both central and transition zones, extends below the verumontanum in patients over age 43 based on prostate magnetic resonance imaging (MRI). In all, 82 patients who underwent preoperative, multiparametric endorectal MRI (1.5T and 3T) at our institution were included. The central gland was defined as a combination of the central zone and transition zone. Two radiologists measured central gland extension below verumontanum using axial, coronal, and sagittal T2-weighted images and coregistration picture archiving and communication system software. The final cohort consisted of 63 patients with a mean age of 60.2 years (standard deviation: 7.1, range: 43-76). The central gland extended below the verumontanum in 60/63 (95%) patients. Mean central gland extension below the verumontanum was 6.5 mm (standard deviation = 3.7, range: 0, 18). Weak (r = 0.35), but significant (P = 0.005) positive correlation was found between age and the amount of central gland extension below the verumontanum. Contrary to McNeal's classical prostatic anatomy teaching, the central gland extends below the verumontanum in 95% of men over 43, likely due to deformation of the gland by benign prostatic hyperplasia. It is important for pathologists to be aware of this observation for accurate characterization of the zonal origin of prostate cancer below the level of the verumontanum.