Introduction

Introduction

Hyperplasia is a general medical term referring to excess cell replication. Benign prostatic hyperplasia (BPH), also called benign prostate hyperplasia, is a noncancerous growth of the prostate gland. It is the most common noncancerous form of cell growth in men and usually begins with microscopic nodules in younger men. BPH, however, is not a precancerous condition. Prostate cancer usually occurs in the outer area of the prostate, called the peripheral zone.

As BPH progresses, overgrowth occurs in the central area of the prostate, called the transition zone, which wraps around the urethra (the tube that carries urine through the penis). This pressure on the urethra can cause lower urinary symptoms that have been the basis for diagnosing BPH. In 2000, an expert committee suggested that the impact of such symptoms on quality of life, including sexual activity, is also important in assessment of the disease.

Click the icon to see an image of BPH.

The Prostate Gland

Description of the Prostate Gland. The prostate gland is located between the bladder and the rectum and wraps around the urethra (the tube that carries urine through the penis). It is basically composed of three different cell types:

• Glandular cells, which produce a milky fluid that liquefies semen.
• Smooth muscle cells, which contract during sex and squeeze the fluid from the glandular cells into the urethra, where it mixes with sperm and other fluids to make semen. The muscle cells are stimulated by molecules called alpha adrenergic receptors.
• Stromal cells (which form the structure of the prostate).

Click the icon to see an image of the male reproductive anatomy.

The central area of the prostate that wraps around the urethra is called the transition zone. The entire prostate gland is surrounded by a dense, fibrous capsule.