An Adequate Sampling of the Prostate to Identify Prostatic Involvement by Urothelial Carcinoma in Bladder Cancer Patients

The distribution of any involved prostatic urethra, ducts and acini by urothelial carcinoma was studied to determine an adequate sampling method for detecting prostatic involvement using the maps of 38 cystoprostatectomy specimens. A total of 31 patients had prostatic duct and acini involvement, while 7 had prostatic urethral involvement alone. However, the distribution of the involved prostatic urethra, ducts and acini varied. In 29 of the 31 patients (93.5%) with prostatic duct and acini involvement, urethral carcinoma in situ and/or superficial gland involvement (an involvement of the afferent ducts within a few millimeters of the urethral mucosa) at the 5 and/or 7 o'clock position of the verumontanum portion was identified. In 7 patients with prostatic urethral involvement alone 2 had carcinoma foci at the 5 and/or 7 o'clock position of the verumontanum portion. Furthermore, the frequency of deeper gland involvement (an involvement of true prostatic acini except for superficial glands) was higher in patients with superficial gland involvement at the 5 and/or 7 o'clock position of the verumontanum portion (57.7%) than in patients without such involvement (20.0%). Therefore, this study emphasizes that a transurethral resection biopsy containing prostatic tissue at the 5 and/or 7 o'clock position of the verumontanum portion substantially improves the detection of prostatic duct and acini involvement in bladder cancer patients. Moreover, if the prostatic superficial glands are involved at the 5 and/or 7 o'clock position of the verumontanum portion, the potential involvement of the deeper glands should also be suspected.