Adenoma of the posterior urethra: 131 case report

Zhen-Guo MI, Xiao-Feng YANG, Xue-Zhi LIANG, Hong-Yao LIU, Shang-Yin LIU, Hong ZHANG,  Dong-Wen WANG, Chun LIU

Department of Urology, The First Affiliated Hospital, Shanxi Medical University, Taiyuan  030001, China

Asian J Androl  2001 Mar; 3: 67-70

Keywords: adenoma; posterior urethra; hemospermia; hematuria

Abstract

Aim: A case-report on adenoma of the posterior urethra. Methods: In 131 cases of adenoma of the poste rior urethra, aged 17-79 (mean: 36.4) years, a detailed medical history was taken and urinalysis, urethroscopy, and prostatic specific antigen (PSA) immunohistochemical staining were performed. They were then treated with transurethral resection (TUR) or transurethral electric coagulation (TUEC). Results: Hemospermia occurred in 51% of the cases, hematuria in 38%, blood overflow from the urethral orifice in 6%, and dysuria in 5%. The position of the tumor was at or around the verumontanum. The appearance of the tumor was similar to those of a papilla, a villus, a dactyl or polyp, or simply an engorgement. The tumor contained glandular alveoli and adeno-epithelial cells. PSA immunohistochemistry was positive in the cytoplasm and nucleus of the adeno-epithelial cell. One hundred and tweenty-nine cases were cured after TUR or TUEC, while 2 patients recurred and were operated again. Conclusion: Adenoma of the posterior urethra is a common cause of hemospermia and hematuria in young men. Urethroscopic examination and biopsy are the principal diagnostic measures. TUR or TUEC are believed to be the treatment of choice with a short-term recurrence rate of around 1.5%.

1 Introduction

Hemospermia is an annoying symptom for young men and generally thought to be the result of vesiculitis.  Antibiotics are commonly used for its treatment, however, they usually  provide no assistance. In 1962 Nesbit reported a 30-year-old man with hemospermia, a lesion was found at his prostatic urethra, and histologically, the tissue was composed of prostate-like glandular material covered with papillary epithelium^[1]. The disease was then reviewed by other urologists, who considered that the lesion represented a developmental disturbance of the underlying prostate gland^[2,3]. During the next 20 years, Nesbit encountered 12 similar patients, aged 24-65 years, almost all of whom presented hematuria. Butterick et al^[4] and Baroudy^[5] carried out systemic studies on the lesions and considered them to be a benign growth, originated from the prostate, and were the most common cause of hematuria and hemospermia in young men.

2 Materials and methods

Between May 1989 and June 2000, 131 cases of adenoma of the posterior urethra were recruited in the First Affiliated Hospital of Shanxi Medical University. A detailed medical history was taken, and routine urinalysis, B ultrasound, and excretory programs were performed.

2.1 Cystourethroscopic examination

Cystourethroscopy was employed for the examination of the bladder and urethra. The examining sheath was usually 21 F. The urethra was examined with a 12 telescope and the bladder with a 70 instrument. While the endoscope was inserted into the urethral orifice, the obturator was drawn out and replaced by the 12 telescope. The telescope should be inserted carefully under irrigation.

The whole urethral mucosa must be checked, beginning from the orifice. The sphincter and the verumontanum were then examined. While the verumontanum was maintained within the visual field at a position of about 6 o'clock, the condition of the prostatic urethra can be examined. This is the most important area, especially that around the verumontanum, to be examined and for taking biopsy specimens.

2.2 Pathological examination

All biopsy specimens were examined microscopically after H/E staining.    

2.3 Prostatic specific antigen (PSA) immunohistochemical staining

Twenty-eight paraffin-embedded specimens were sectioned to a thickness of 4 m, deparaffinized in xylem, hydrated in graded alcohol, and placed in 20 mM phosphate-buffered saline at pH 7.4. The endogenous peroxidase activity was blocked by immersing the slides in 0.1% hydrogen peroxide and absolute methanol for 30 minutes. The sections were then treated sequentially at room temperature with normal goat serum (1:10, 30 minutes), rabbit anti-PSA, rabbit gammaglobulin, and rabbit antiperoxidase-peroxidase complex. Three 5-minute rinses with PBS were performed between antibody applications. The reaction was developed using 3,3-diaminobenzidine as the chromogen. All sections were lightly counter-stained with hematoxylin. Positive controls consisted of normal prostate and negative controls were bladder tumors, with the substitution of normal rabbit serum for the primary antibody^[6]. 

2.4 Treatment

3 Results

The principal complains included hemospermia, hematuria, blood overflow from the urethral orifice and dysuria. Some patients complained of suprapubic pain, perineal discomfort, and/or urinary frequency.  The course of disease was from 3 days to 5 years (mean: 11 month).

3.1 Clinical manifestations

3.1.1 67 cases (51%) had hemospermia: 40 occasional hemospermia, 27 frequent hemopermia.

3.1.2 50 cases (38%) had hematuria: 30 at the end of urination, 11 at the beginning of urination, 7 microscopic hematuria, 2 massive post-ejaculation hematuria.

3.1.3 8 cases (6%) had overflow of blood from the urethral orifice.

3.1.4 6 cases (5%) had dysuria.

3.2 Tumor characteristics

All lesions were restricted to the prostatic urethra. In 27 cases (21%) the lesions were on or around the verumontanum, 47 cases (36%), ambilateral to the verumontanum, 25 cases (20%), distal to it and 32 cases (23%) on both the verumontanum and the wall of urethra.

The lesions looked like pink papillas, villi, or dactylate or polypoid prominences, with the greatest dimension of 1-6 mm. 121 cases (92%) had multiple lesions and the rest had a single lesion. In some cases there was coexisting vasodilatation or vaso-engorgement.

3.3 Pathological characteristics

The lesions were papillary processes lined by columnar or transitional epithelium with basally located nuclei closely resembling that of the prostatic acinar epithelium. The stroma of the polypoid lesion is composed of connective tissue with rich vascular components. Telangiectasis and some extravasated blood are noted in the core stroma (Figure 1).

Figure 1. Pathological characteristics: The figure displays papillary processes, which are lined by columnar or transitional elpithelium, closely resembling prostatic acinar epithelium. The stroma of the polypoid lesion is composed of connective tissue with rich vascular cpmponents.

3.4 PSA immunohistochemical staining

PSA immuno-histochemical staining was performed in 28 cases. The cytoplasm and nucleus of the adeno-epithelial cell were stained brown. It looked like normal prostatic tissue or benign prostatic hyperplasia (Figure 2).

Figure 2. PSA immunohistochemical staining: The cytoplasm and nucleus of the adeno-epithelium cell were stained brown. It looked like normal prostatic tissue or benign prostatic hyperplasia.

3.5 Treatment

4 Discussion

Adenomatous polyps with prostatic type epithelium in the prostatic urethra were recognized as early as 1913 by Rabdall^[7], and later by Nesbit^[1], and Butterick et al^[4]. Due to their morphologic resemblance to the prostatic epithelium, these lesions were regarded as prostatic origin in the past. Clinically, the main finding is small, usually solitary, polypoid sessile lesions at the prostatic urethra or verumontanum. The lesions bleed easily and may cause hematospermia or hematuria^[8,9].

In 1984 Baroudy indicated that papillary adenoma of the prostatic urethra was a common cause of hemospermia and hematuria in young men^[5]. Recently, Segal et al^[12] and Gattoni et al^[13] studied a large group of adenoma of the prostatic urethra and pointed out that the most commonly encountered benign tumors of the urethra were viral papillomas (67.3%), polyps (22.4%), and angiomas (10.3%).

We reported a 10-year follow-up (1990-2000) on 131 males with benign tumors of the urethra, a common disease in young men. All lesions were restricted to the prostatic urethra. 

Urethroscopic examination and biopsy under direct vision plays the main role in detecting the lesion. Excretory urograms and ultrasound may fail to reveal the defects. The lesions are very small, only 1-6 mm in their greatest dimension and are easily damaged by the scope sheath. Thus we suggest that the scope should be inserted very carefully under direct vision and irrigation. Due attention must be paid to the prostatic urethra when cystoscopic observation is performed in young men with hemospermia or hematuria.

The lesion probably represents an error in the invagination process of the submucous glandular material during the embryonic development of the prostate. In each papillary body there is usually a capillary network, which can easily be traumatized when exposed to the rushing force of ejaculation or forceful urination and the result is apparent hematuria^[8,13].

References

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[13] Gattoni F, Avogadro A, Sacrini A, Blanc M, Pozzato C, Spagnoli I, et al. Transrectal prostatic echography in the study of hemospermia. An assessment of an 85-patient case load. Radiol Med (Torino) 1996; 91: 424-8. 
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Correspondence to: Dr Xiao-Feng YANG, Department of Urology, The First Affiliated Hospital, Shanxi Medical University, Taiyuan 030001, China. 
e-mail:  urology@public.ty.sx.cn
Received 2000-10-18     Accepted 2001-02-19