Table of Contents

Chapter 2: Initial Treatment: Weighing the Pros and Cons of Each Option

b. A Lesson in Anatomy and Physiology

Before we move on to the details of surgery and radiation therapy, you will need to understand where the prostate is, what it does, and what surrounds it in the body. Not only will this help you better understand how each of the different procedures attempts to accomplish its goals, it will also help you understand why surgeons and radiation oncologists have been spending so much time perfecting their crafts, with a look toward maximizing treatment benefit while minimizing side effects.

The prostate is a small, squishy gland about the size of a walnut that sits under the bladder and in front of the rectum. The urethra, the narrow tube that runs the length of the penis and that carries both urine and semen out of the body, runs directly through the prostate.

After the kidneys filter out waste products from the blood, the resultant urine is stored in the bladder. Under normal circumstances, the urinary sphincters, bands of muscle tissue at the base of the bladder and at the base of the prostate, remain tightly shut until they are relaxed during urination. During prostatectomy, after the prostate is removed, the bladder is pulled downward and is connected to the urethra at the point where the prostate had sat. If the sphincter at the base of the bladder is damaged during this process, or if it is damaged during radiation therapy, some measure of urinary incontinence or leakage will occur.

Sitting just above the prostate are the seminal vesicles, two little glands that secrete about 60% of the substances that makes up semen. It is estimated that about 10% of men have what is known as seminal vesicle invasion, meaning that the prostate cancer has either spread into the seminal vesicles or has spread around them, so the vesicles are typically removed during prostatectomy and are targeted during radiation therapy. The loss of the prostate and the seminal vesicles renders men infertile.

Running alongside and attached to the sides of the prostate are the nerves that control erectile function. If these nerves are damaged, which was standard during prostatectomy up until the mid 1980s, the ability to achieve erection is lost. Sexual desire is not affected, but severing or otherwise damaging the nerves that stimulate the processes by which erection occurs leads to erectile dysfunction.

Finally, sitting just behind the prostate and the bladder is the rectum, the lower end of the bowel just above the anal sphincter. Solid waste that is filtered out of the body moves slowly down the intestines, and, under normal circumstances, the resultant stool is excreted through the anus following conscious relaxation of the sphincter. Damage to the rectum caused by radiation, or,more rarely, by surgery, can result in a number of bowel problems, including rectal bleeding, diarrhea, or urgency.