Incidence and location of prostate and urothelial carcinoma in prostates from cystoprostatectomies: implications for possible apical sparing surgery.

PURPOSE: Prostatic carcinoma (Pca) at cystoprostatectomy is usually an incidental finding with the majority thought to be clinically insignificant. Most studies have not specifically addressed the location of Pca or the incidence and location of in situ or invasive urothelial carcinoma (Uca) in prostates of cystoprostatectomy specimens. The frequency of involvement of the apex with these processes has clinical implications. Specifically urinary continence following orthotopic diversion may be enhanced by prostate apical sparing. In this study the pathological features of Pca and Uca, and the frequency of apical involvement were investigated in prostates from cystoprostatectomy specimens.

MATERIALS AND METHODS: Whole mounted prostates from 121 consecutive cystoprostatectomy specimens were analyzed. Pca location, tumor volume, grade, stage, surgical margin and pelvic lymph node status of Pcas were assessed. Clinically insignificant Pcas had a volume of less than 0.5 cc without Gleason pattern 4, extracapsular extension, seminal vesicle invasion, lymph node involvement or positive surgical margins. Prostate involvement by Uca or urothelial carcinoma in situ (CIS)/severe dysplasia and its location were assessed.

RESULTS: Of 121 prostates 50 (41%) had unsuspected Pca, of which 24 (48%) were clinically significant. Of Pcas 30 of 50 (60%) involved the apex, including 19 of 24 (79%) that were significant and 11 of 26 (42%) that were insignificant. Of 121 prostates 58 (48%) had Uca involving the prostatic stroma, noninvasive Uca or urothelial CIS/severe dysplasia in the prostatic urethra or periurethral ducts, of which 19 (33%) had apical involvement. Overall only 32 of 121 patients (26%) had no Pca or prostate Uca/CIS and only 45 (37%) had no clinically significant Pca or Uca/CIS in the prostate. However, 74 of the 121 patients (61%) had no prostatic apical involvement by Pca or Uca/CIS and 85 (70%) had no apical involvement by clinically significant Pca or Uca/CIS. Patients with prostatic apical involvement by invasive or in situ Uca uniformly had involvement of more proximal (toward the base) portions of the prostate.

CONCLUSIONS: The majority of prostates from cystoprostatectomies had no involvement of the prostatic apex by Uca or clinically significant Pca. Hence, most patients may be candidates for prostate apical sparing. However, involvement of the apex by Uca in any patient raises concern about procedures that leave portions of the prostate urethra after cystectomy in an effort to improve continence. In candidates for orthotopic neobladder reconstruction removing all of the prostatic urethra and sparing the remainder of the prostatic apex may allow improved preservation of urinary continence with an acceptable low risk of clinical Pca progression. Whether future strategies for preoperative exclusion of apical Pca and intraoperative assessment of more proximal prostate to help exclude apical urothelial disease may identify patients suitable for prostatic apical sparing remains to be determined. The impact on functional outcomes and cancer control also require additional study.