Treatment Path with Simultaneous Radiation, HT and Chemo

After a PSA of 37 which indicated a PSA doubling in 6 months, an MRI with two PIRAD 5 tumors in my prostate, a biopsy which showed the two tumors were Gleason 4+5 and a PET/CT scan which showed the cancer had metastasized to my pelvic lymph nodes and one in the pelvic side wall, I would say that I have an aggressive form of prostate cancer. The good news is that there were no tumors outside my pelvic region large enough to appear on the PET/CT scan.

I began HT last week and will begin proton therapy at the end of the month. However, what about chemo as well? Perhaps because I just turned 83 it is not advisable to have proton, HT, and chemo simultaneously? The side effects just too much? Perhaps the path is to begin chemo and continue HT after radiation completed?

I would be interested in the experience of anybody of a similar age who has had all three simultaneously. As an addendum, in the week after beginning Lupron no side effects whatsoever. Nature has cut me a little slack.