Prostate cancer is very common among men. Each year, more than 250,000 men are diagnosed in the United States, and 1 in 3 men older than 70 has a trace of the condition in their body.

Although most patients do not die from prostate cancer, the condition still ranks as the second leading cause of cancer death among American men.

“Prostate cancer that’s just in the prostate is generally not very dangerous,” says Paul L. Nguyen, MD, a Mass General Brigham radiation oncologist. “But, if it spreads to other places, it can sometimes lead to death.”

Nguyen is vice chair for clinical research at Brigham and Women’s Hospital. He explains prostate cancer risk factors, signs and symptoms, and treatment options.

What causes prostate cancer?

The prostate is a walnut-sized organ found in men. It connects the bladder and several reproductive organs to the penis.

Like any organ in the body, the prostate constantly makes new cells as old ones die. The body creates new cells by copying healthy, existing cells, almost like a photocopier. Unfortunately, mistakes can happen during this process. Sometimes the photocopier loses control of how many copies it prints, or smudged ink alters the appearance of a photo.

Similar errors happen when creating new cells. These errors, called mutations, may trigger cells to reproduce too rapidly or produce cells unable to function. When normal prostate cells transform and behave abnormally, prostate cancer occurs.

According to Nguyen, doctors don’t know the exact causes of prostate cancer. However, some factors put men at a higher risk for the condition. These include:

• Family health history: Some men inherit mutations. If you have family members who’ve had prostate cancer, you’re more likely to develop the condition.
• Race: African American men are diagnosed at a rate more than 60% higher than white men.

How is prostate cancer diagnosed?

Doctors feel for any unusual lumps or bumps on the prostate during a routine prostate exam. A prostate-specific antigen (PSA) test also helps doctors diagnose the condition.

During the test, a doctor draws blood from a patient and tests for microscopic proteins unique to the prostate. These proteins, called antigens, serve as “breadcrumbs” for prostate cells. If the prostate grows abnormally fast, it leaves behind more breadcrumbs than usual, which can leak into the bloodstream.

Prostate cancer is not the only condition capable of elevating PSA levels, however. According to the National Institutes of Health, harmless conditions, such as an inflamed or enlarged prostate, can cause PSA levels to spike.

“A PSA test can’t diagnose cancer by itself,” says Nguyen. “If a score is suspiciously high, we need to figure out why by ordering more tests.”

Doctors concerned by a PSA test can order two additional tests to determine a diagnosis:

1. MRI (magnetic resonance imaging): Imaging the prostate can reveal tumors on its surface.
2. Needle biopsy: Extracting a tiny tissue sample from the organ allows doctors to assess for any cancerous cells

Read more about prostate cancer symptoms, treatment, and the future of prostate cancer care at massgeneralbrigham.org