Benign polyps with prostatic-type epithelium of the urethra

Prostatic ductal adenocarcinoma presenting as a urethral polyp: a clinicopathological study of eight cases of a lesion with the potential to be misdiagnosed as a benign prostatic urethral polyp

AIMS

Centrally located prostatic ductal adenocarcinoma can present as a single urethral polyp mimicking a benign polyp. Such lesions have not been formally studied.

METHODS AND RESULTS

Clinicopathological and immunohistochemical findings of eight cases were analysed. Patients (mean age 76 years) presented with urinary symptoms and haematuria. Mean serum prostate specific antigen (PSA) was 7.01 ng/mL (range 1.04-21). Single small polyps were seen on cystourethroscopy with a clinical diagnosis of benign polyps. The most common architectural patterns were cribriform and papillary. Five cases had mild cytological atypia, three of which were initially diagnosed as benign prostatic urethral polyps. All cases were positive for PSA and 34betaE12. Seven cases tested were positive for AMACR (a-methylacyl-CoA racemase), p63 and cytokeratin (CK) 7 and 70% for CK20. Proliferative activity defined as Ki-67 labelling index was high (mean 26%, range 20-35%). Adenocarcinoma, predominantly ductal, was found in other specimens in four patients.

CONCLUSIONS

Centrally located prostatic ductal adenocarcinoma has the propensity to mimic benign urethral polyps clinically and histopathologically. Basal cell immunostaining may not help with this distinction but AMACR is useful. Prominent glandular complexity including cribriform patterns, nuclear pseudostratification, at least mild atypia and a high Ki-67 index distinguish these lesions from prostatic urethral polyps.

Ectopic prostatic tissue in the uterine cervix: a report of four cases and review of ectopic prostatic tissue

We report four examples of prostatic tissue occurring in the uterine cervix of patients aged 22, 25, 31, and 77 years. Three were incidental findings in loop excisions (two patients) and cone biopsy (one patient) of the cervix for high-grade squamous dysplasia. One presented as a cervical mass, clinically suspected to represent a fibroid. The prostatic tissue consisted of ducts and acini, some of which had papillary or cribriform patterns. Squamous metaplasia was prominent in all cases. No Wolffian duct tissue was present. The glandular epithelium in all cases was positive for prostatic acid phosphatase and prostate-specific antigen. High molecular weight keratin, performed in two cases, highlighted basal cells in a manner similar to the normal prostate. These unusual cases, only one of which is documented previously, further complicate the often-challenging area of interpretation of benign glandular lesions of the cervix. The unusual phenomenon of ectopic prostate tissue in general is reviewed.

Prostatic-type epithelium in urinary bladder. Clinical, histologic, and immunohistochemical study

Six cases of urinary bladder mucosa with prostate-type epithelium were studied clinically, morphologically, and immunohistochemically. All patients were male with an average age of fifty-three years; most presented with painless hematuria. Histologically, two types of lesions were observed, the polypoid located in various sites of the bladder wall and the flat lesion found in the bladder neck. Both lesions shared in common a prostatic-type and transitional surface epithelium while prostatic-type glands were prominent in the polypoid lesion. The prostatic-type epithelium was confirmed immunohistochemically by detection of prostatic specific antigen and prostatic acid phosphatase. Based on specific findings we considered the metaplasia as the most reliable histogenetic aspect.

Painless hematuria and urethral discharge secondary to ectopic prostate

We report a case of ectopic prostatic tissue found in the penile urethra of a 16-year-old boy. A literature review and discussion of this rare entity are presented.

Intestinal metaplasia and dysplasia of prostatic urethra secondary to stricture

We report a case of intestinal metaplasia and dysplasia (villous adenoma) of the prostatic urethra secondary to stricture of the prostatic portion of the urethra and chronic inflammation. This sequence of events has previously been recognized in the urothelium of the bladder as a precursor of adenocarcinoma of intestinal type. Premalignant dysplasia of glandular type is rare in the urethra, as is adenocarcinoma, and this case suggests that the pathway to some adenocarcinomas of the urethra may be through intestinal metaplasia and dysplasia similar to the process recognized in the stomach, nose, and urinary bladder.

Benign villous polyp with prostatic type epithelium of the penile urethra

We report a case of a benign polyp of the penile urethra composed of prostatic type epithelial tissue. The etiology, pathology, diagnosis and treatment of these uncommon lesions are discussed.

Prostatic-type polyps of the lower urinary tract: three histogenetic types?

Seventeen prostatic-type polyps of the lower urinary tract are reported. All occurred in males, and the mean ages of the patients with ureteric orifice, bladder and urethral polyps were 20.5, 60.2 and 36.6 years, respectively. The commonest presentation for the bladder and ureteric orifice polyps was haematuria, whereas that for the urethral polyps was either dysuria or haematuria. The polyps consisted of acini and papillae lined by prostatic-type epithelium, as confirmed by immunostaining for prostatic-specific antigen. Most had interspersed islands or complete covering of transitional epithelium on the surface. We believe that the histogenesis of prostatic-type polyps may differ in the different sites. For the ureteric orifice polyp, the early age of presentation and the simple occurrence of prostatic acini beneath an intact urothelium suggest a developmental abnormality. For the bladder polyp, the late onset of disease and the commonly observed transition with cystitis cystica-glandularis suggest that it may be a metaplastic variant of cystitis cystica-glandularis. On the other hand, the urethral polyp probably represents a hyperplastic lesion, since the prostatic urethra is normally lined partly by prostatic-type epithelium.

Ectopic prostatic glands in bulbar urethra. Immunoperoxidase study

Ectopic prostatic glands in the bulbar urethra of a sixty-year-old man were identified by an indirect immunoperoxidase stain for prostatic acid phosphatase. Cystoscopically the appearances were those of "urethritis" without the polypoid appearance previously reported in cases of ectopic prostatic tissue.

Ectopic prostatic tissue in bladder trigone. Distinctive cause of hematuria

A rare instance of ectopic prostatic tissue involving the bladder trigone is documented. This distinctive lesion probably arises from a vestigial prostatic remnant and may cause hematuria in the post-pubertal male.

Benign prostatic epithelial polyp of the urethra

Acquired polyps of the male urethra often present with hematuria and sometimes hemospermia. The histogenesis of these tumors has been debated. We report a case of a prostatic urethral polyp that proved to be of prostatic epithelial differentiation, as demonstrated by immunohistochemical identification of prostatic acid phosphatase and prostatic specific antigen within the tumor cells.

Polyps and papillary lesions of the prostatic urethra

There is confusion over the type and nature of polypoid and papillary lesions of the prostatic urethra. These are uncommon growths which may present clinically with hematuria, frequency, obstruction or hematospermia. Pathologically, they usually occur in the region of the verumontanum and show papillary epithelial overgrowth. There is much variation in the terminology applied to such lesions, and many different theories of histogenesis have been advanced. Both benign and malignant lesions may occur. Two cases, one benign and one malignant, are described. The literature is reviewed and a rational nomenclature and histogenesis are proposed.

Adenomatous polyp of the bladder: a rare cause of hematuria in young men

A 26-year-old black man presented with gross hematuria and was found to have a papillary lesion of the trigone of the bladder. The lesion proved to be an adenomatous polyp with prostatic-type epithelium. This type of neoplasia ordinarily is found in the prostatic urethra and has not been reported previously in the bladder. Adenomatous polyps are benign tumors and should be considered in the differential diagnosis of hematuria in young men.

Villous polyps of the urethra: a report of two cases

Two patients with villous polyps of the prostatic urethra are described. The article supports previous observations that the lesion has the morphologic appearance of prostatic tissue. A review of the literature reveals that this rare lesion appears to be specific for the prostatic urethra and behaves as a benign tumor.

Polyps of the urethra in children

The authors present two cases of polyps of the urethra occurring exclusively in boys: one in a 12-month-old infant, the other in a 15-year-old boy. In both patients the polyp caused dysuria or urinary retention. Diagnosis was based on mictional cystography. This examination usually gives a picture of a filling defect spotted in the area of the bladder neck. During miction the defect may move deeper into the urethra. An endoscopic examination may be also helpful. The authors believe that treatment should consist in total excision of the polyp together with its base through the open urinary bladder. Polyps of the urethra have to be differentiated from a valve of the posterior urethra or a shadowless calculus. After total excision of the polyp prognosis is good.

Submucosal fibromatosis: prostatism in a young boy?

A seven-year-old boy was seen with a urodynamically significant, obstructing, posterior urethral mass. It was believed to represent either a fibromuscular prostatic enlargement or a nonpedunculated congenital polyp. The differential diagnosis is discussed. Transurethral resection of the mass resulted in decreased voiding pressure and relief of symptoms.

Papillary adenocarcinoma of prostate

Papillary adenocarcinomas of the prostate are rare tumors which may arise from the prostatic ducts and the utricle; 2 cases are described. The diagnosis of these tumors is best established by cystourethroscopy and transurethral resection. The more common prostatic acinar adenocarcinoma is frequently associated with these tumors. The histopathologic recognition of papillary adenocarcinoma of the prostate and its differentiation from acinar adenocarcinoma is important since the natural history and response to treatment may be different.