• Clinical science

Benign prostatic hyperplasia

Abstract

Benign prostatic hyperplasia (BPH) is a non-neoplastic glandular and stromal hyperplasia of the transition zone of the prostate. It is a common disorder affecting ∼ 40% of the male population by the age of 50 years. Although the etiology has not been conclusively established, sex hormones (androgens, estrogens, and androgen-estrogen imbalance) have been implicated as a key factor in the development of prostatic hyperplasia. Patients present with symptoms of bladder irritation (urinary frequency, urgency, urge incontinence), bladder outlet obstruction (urinary hesitancy, straining to urinate, sensation of incomplete voiding), and/or hematuria. Digital rectal examination reveals a smoothly enlarged, non-tender, and firm prostate. Diagnosis can be confirmed on abdominal ultrasound which demonstrates an enlarged prostate and increased post-void residual urine in the bladder. Bladder outlet obstruction can be quantitatively measured on uroflowmetry which shows a decreased maximal urinary flow rate. BPH is graded as mild, moderate and severe based on the frequency and severity of the symptoms. Behavioral modifications (night-time fluid restriction, urinating in a sitting position, etc.) are advised in all patients who are managed conservatively. Patients with mild/moderate BPH respond well to medical management with alpha-blockers (tamsulosin, doxazosin), 5-alpha-reductase inhibitors (finasteride), and parasympatholytics (oxybutynin). Severe BPH, unsuccessful medical therapy, and complications due to BPH are indications for surgery (e.g., transurethral resection of prostate, TURP). Complications of BPH include recurrent urinary tract infections (UTIs), urinary retention, bladder calculi, hydroureteronephrosis, and chronic kidney disease. BPH can recur after TURP in ∼15% of men. Prostate cancer can occur in patients with BPH, including in those who have undergone TURP. Normal prostate specific antigen (PSA) screening protocol is followed in these patients.

Definition

References:[1]

Epidemiology

  • Age: Prevalence of BPH increases with age (∼ 40 % of males > 50 years). > 80% in people > 80 years; < 10% in people < 40 years
  • Race: The severity of symptoms of BPH and the size of the prostate are greater in blacks.

References:[1][2]

Epidemiological data refers to the US, unless otherwise specified.

Etiology

BPH is not a risk factor for the development of prostate cancer.

References:[2][3][4][5][6]

Pathophysiology

References:[1][3][7]

Clinical features

  • Lower urinary tract symptoms (LUTS)
    • Irritative symptoms of BPH
    • Obstructive symptoms of BPH
      • Hesitancy
      • Straining to urinate
      • Poor and/or intermittent stream
      • Prolonged terminal dribbling
      • Sensation of incomplete voiding
  • Often gross hematuria
  • Digital rectal examination (DRE): symmetrically enlarged, smooth (no nodules), firm, nontender prostate with rubbery or elastic texture
  • International Prostate Symptom Score (IPSS)
    • A scoring system based on the presence and severity of seven particular BPH symptoms in the past 30 days
    • Based on the final scores, BPH is graded as follows:
      • 0–7 points: mild symptoms
      • 8–19 points: moderate symptoms
      • 20–35 points: severe symptoms
    • IPSS is also useful as a prognostic marker of disease progression and response to treatment

References:[8][1][7][9][10][11][12]

Diagnostics

References:[13][14][15][16]

Differential diagnoses

The differential diagnoses listed here are not exhaustive.

Treatment

Conservative management

Surgical intervention

  • Indications
    • Severe BPH symptoms with/without complications (see IPSS above)
    • Moderate BPH with complications (see below)
  • Transurethral resection of the prostate (TURP)
  • Transurethral incision of the prostate (TUIP): indicated in patients with small prostates with obstructive symptoms or those at high risk for surgical complications
  • Laser ablation, radiofrequency ablation, microwave thermotherapy are other newer techniques used for prostate tissue resection.
  • Open/laparoscopic/robotic prostatectomy: Indicated in patients with very large prostates (> 75 g)
    • There are many approaches to surgically remove the prostate. e.g., Freyer's transvesical prostatectomy (enucleation of the prostate through the anterior wall of the bladder. Since the incision is a suprapubic, extraperitoneal incision, the procedure is also called suprapubic prostatectomy); retropubic prostatectomy; perineal prostatectomy

Since the peripheral zone (in which prostate cancer can develop) is left intact in TURP, the risk of developing prostate cancer after TURP is the same as that of the general male population. Normal PSA screening protocol should be followed.

Almost all surgical interventions lead to retrograde ejaculation into the bladder because of anatomical changes!

References:[17][18][1][19]

Complications

References:[1]

We list the most important complications. The selection is not exhaustive.