Prostate cancer is one of the most treatable forms of cancer, especially when caught early enough. That's why regular prostate checkups are so important. Once a man reaches the age of 40, the prostate can become enlarged or inflamed. These problems can lead to difficulty urinating, among other symptoms. On the other hand, prostate cancer may have no symptoms until it has advanced. Then it may be harder to treat.

The American Urological Society and the American Cancer Society recommend that all men over age 50 have annual prostate screening. Those at high risk of prostate cancer should begin in their forties.

A regular exam usually starts with your doctor asking about any family history of prostate cancer. Next your doctor may perform the most basic prostate screening: the digital rectal exam (DRE). The doctor inserts a gloved finger into the rectum to check for enlargement or a lump on the prostate. If there is a problem, he may refer you to an urologist, a physician who specializes in the male urinary tract and reproductive system.

The urologist might order a PSA test. This simple, inexpensive test measures the amount of prostate-specific antigen (PSA) in your bloodstream. PSA is a protein made only by the prostate. Generally when a test shows higher than normal PSA levels, there's a greater chance of having prostate cancer. The test itself does not diagnose prostate cancer. And there can be many reasons other than cancer for PSA levels that are high.

If the PSA and/or DRE results are not normal, your doctor may order an ultrasound and possibly a biopsy. An ultrasound uses sound waves to find any abnormal areas in the prostate. It also helps the doctor measure the size of the prostate and look for cancerous tissue. With a biopsy, the physician uses a needle to remove some prostate cells (often with the help of an ultrasound). The cells are sent to a laboratory where a pathologist estimates the tumor's growth rate.

Depending on the results of these tests, you may also have X-rays, CT (computed tomography) scans and/or bone scans. A CT scan is not usually called for unless the cancer is large and fast growing, or it may be ordered because there is a high PSA level. The CT scan shows whether the cancer has spread to the pelvic lymph nodes, usually the first place it spreads beyond the prostate gland.

Early stages of prostate cancer may have no symptoms at all. However, there are several signs that may indicate a problem and warrant a checkup. They are:

• Difficulty urinating or starting to urinate
• Painful urination
• Sudden decrease in size and force of urinary stream
• Blood in the semen or urine
• Frequent trips to urinate/difficulty in holding urine
• Awakening to urinate at night
• Weak stream that stops and starts
• Pain during ejaculation
• In late stages, pain in the back, hips, thighs or shoulders
• Weight loss and fatigue

As with any cancer, prostate cancer is basically uncontrolled cell growth. Cancerous cells divide and form tumors, which eventually may encroach on other healthy cells, using up their oxygen and nutrients. With prostate cancer, a tumor usually starts on the outer part of the gland and spreads to the inside. The tumor has to get fairly large before it interferes with the urinary tract.

If the tumor stays inside the prostate, it's localized. If it spreads to other parts, then it has metastasized. Typically, prostate cancer spreads to the tissue around the gland first, before spreading into the lymph nodes or bones. These are the four stages or grades of prostate cancer/tumors:

• Stage A: Low grade and the least serious. It is small and confined to the prostate gland
• Stage B: Can be felt during digital rectal exam. Confined to the prostate. Tumor size can vary and may indicate probability for a cure
• Stage C: Spread beyond the prostate. May be limited to the surrounding tissues
• Stage D: Spread to lymph nodes and distant locations throughout the body, such as bones. Cure is unlikely at this stage