Prostate cancer starts when cells in the prostate gland grow out of control. Those cells can spread to other parts of the body and affect healthy tissue.

This can happen for several reasons.

Early Treatment Failure

When prostate cancer is discovered early, treatment usually works. Most men are able to live cancer-free for many years.

But sometimes, treatment doesn't work and prostate cancer can slowly grow.  This can happen after surgery (called a radical prostatectomy) or radiation therapy.

Sometimes called a chemical recurrence, it's when the cancer survives inside the prostate or reappears and spreads to other tissues and organs. The cancer is usually microscopic and grows very slowly.

Active Surveillance.

Because prostate cancer cells usually grow very slowly, some men might not need treatment right away.

Your doctor might suggest something called active surveillance. That means instead of having surgery or radiation right away, you and your doctor will track your cancer for a while to see if it gets more serious. You'll have regular tests, like PSA levels, and possibly biopsies and MRI. And if your cancer gets more aggressive, you and your doctor will figure out the next steps.

This plan is usually for men who don't have symptoms and whose cancer is expected to grow slowly. It's also an option when surgery or radiation could be harmful.

Watchful Waiting.

Another potential plan is watchful waiting. Like active surveillance, this avoids surgery and radiation, and you and your doctor watch the progress of your cancer. But with watchful waiting, you don't have regular testing.

Most often, this is the best option for people who don't want or can't have other cancer treatments, or those who have another serious medical condition. The risk with this approach is that the cancer might grow and spread between checkups. If it does, this could limit which treatment you could take and if your cancer can be cured.

Sources - https://www.webmd.com/prostate-cancer/prostate-cancer-spreads

Photo Credits -

https://www.webmd.com/prostate-cancer/prostate-cancer-spreads