Prostatic involvement by transitional cell carcinoma in patients with bladder cancer and its prognostic significance.

To study the importance of prostatic involvement by transitional cell carcinoma (TCC) in patients with bladder cancer, we examined the entire prostates by whole-mount sections from 214 radical cystoprostatectomy specimens for detailed patterns of involvement by TCC and correlated the results with lymph node metastasis and patients' survival. Prostatic involvement by TCC was detected in 69 (32%) of 214 cases. Among them, 30 (43%) patients had carcinoma in situ (CIS) and the other 39 (57%) were invasive TCC. Carcinoma in situ occurred in either prostatic urethra (n = 6, 20%) or, more commonly, in prostatic ducts/acini (n = 14, 47%), and in a combination of prostatic urethra and ducts (n = 10, 33%). Ten (26%) of the invasive TCC resulted from direct penetration from the primary tumor in the bladder, and the remaining 29 (72%) cases arose from prostatic urethra/ducts, of which 11, 13, and 5 invaded the lamina propria, prostatic stroma, and periprostatic or seminal vesical tissue, respectively. Both prostatic TCC involvement and nodal metastasis were highly significant prognostic factors for patients' survival and the survival significance of prostatic TCC involvement still existed regardless of lymph node status. Furthermore, the presence of prostatic CIS and degrees of prostatic invasion are associated with nodal metastasis and survival. Patients with prostatic CIS or urethral lamina propria invasion had a similar, but higher incidence of lymph node metastasis and lower long-term and 5-year survival than those patients without prostatic involvement. Similarly, prostatic stromal invasion and periprostatic/seminal vesical invasion had a similar, but much higher nodal metastasis and worse survival than patients with only prostatic CIS or urethral lamina propria invasion. In summary, presence of prostatic TCC involvement and levels of involvement are significant prognostic factors in patients with bladder cancer.