Screening for prostate cancer is controversial. The U.S. Preventive Services Task Force says the tests often may find cancers that are so slow-growing that medical treatments, which can have serious side effects, may offer no benefit.
If you and your doctor decide to check your PSA levels, every 2 years (or more) may better than yearly tests. That gives you most of the benefits and fewer false positive results.
Routine PSA screening isn’t recommended for men older than 70 or for any man who is expected to live only 10-15 more years.