The DRE is very subjective. It's common to have experienced docs disagree on the presence of a small nodule. Also, not all nodules are cancer, and not all cancers present as nodules. PSA's can fluctuate, with infection, inflammation, recent ejaculation, even bike riding, so hopefully the next PSA will be lower. The PSA "normal" range is <4.0, however that must be interpreted in the context of previous PSA's and age. For someone 50 y/o, a PSA > 2.5 is high. A PSA of 3.5 might be ok in a 70 y/o, unless in was 1.0 the year before.
Hopefully, you will never be diagnosed with prostate cancer, but for those with early-stage (PSA<10, Gleason 6 or even 7) treatment may not even be needed. For those who want or need treatment, there are so many good options, surgically and with several forms of radiation therapy, that picking treatment is like picking your poison. Each option has pros and cons, and treatment should be highly individualized.
I would warn all about radiation centers that are privately owned by physicians, either the urologist or radiation oncologist. This is increasingly common throughout the country because of the profits one can make with a particular form of radiation called IMRT. There is inherent conflict of interest at those centers. Medicare will reimburse $35,000-$45,000 to a doc that prescribes a radiation called IMRT if that doc owns the machine. To do a prostatectomy, a urologist might only get $1200. To do a seed implant, a radiation oncologist gets reimbursed about $1200. Which treatment do you think a doctor who does not have your best interest in mind will recommend? Just one of the problems with US healthcare.