Carcinoma arising from the prostatic urethra is uncommon as compared with those originating from the bladder or prostate. The cell types mostly are transitional cell carcinoma of the prostatic urethra or adenocarcinoma of the prostatic gland. Carcinoma arising from the prostatic urethra unrelated to transitional or prostatic epithelium is extremely rare.
Herein we report a 98-year-old man presented to our OPD with the chief complaint of initial gross hematuria. Cystourethroscopy revealed a 1.5 cm nodular lesion with papillary surface inside the prostatic urethra just distal to the verumontanum. Transurethral resection of the tumor was done. Pathologic examinations revealed a moderately differentiated adenocarcinoma. Deep bites of the tumor bed showed no residual tumor. Interestingly, Immunohistochemical studies of this adenocarcinoma demonstrated that these tumor cells were stained positively for CK18 and negatively for PSA, CK7, CK20, CK14, vimentin, and TTF-1. This indicated the origin of this adenocarcinoma was unrelated to prostatic glandular epithelium, nor related to transitional cell epithelium of the prostatic urethra. Although the definite origin of this rare primary adenocarcinoma of the prostatic urethra is unknown, the most likely source of this tumor was from the prostatic accessory gland. Since this patient was 98-year-old and the above mentioned carcinoma was still in its early stage, the real biologic behavior of this tumor and whether it has a predilection to very old man should be further investigated. |
