WILLIAM OH, MD: A digital rectal examination or DRE is when a urologist or an oncologist or a primary physician inserts a gloved finger into the rectum to feel where the prostate is. And this is the traditional way in which prostate cancers were detected before the advent of PSA screening. So if there's an abnormal prostate on examination, that's similar to finding a lump on the breast.
ANNOUNCER: PSA, short for prostate specific antigen, is a protein produced by prostate cells. Levels tend to rise with non-cancerous changes to the prostate that are normal with aging, a condition called benign prostatic hyperplasia, or BPH. However, a high or rising level can also indicate cancer. Doctors used to consider a PSA of 4 units a critical mark.
WILLIAM OH, MD: In general, this traditional cutoff for an elevated PSA was 4 or higher. However, we've become much more sophisticated over the last decade in understanding what the context is for a high PSA. So, for example, a level of 4 in a 50-year-old man would be considered abnormal, even though it's considered normal for the total range, and that's because men who are younger tend to have smaller prostates and therefore have a lower PSA at their baseline. Whereas, if you were 70 years old or 75 years old and had a history of having trouble urinating, BPH symptoms, a PSA of 4 could be perfectly within normal range.
ANNOUNCER: The PSA count is not a direct indicator of cancer, so it can not be the basis of diagnosis.
