81-Year-Old Man with Prostate Cancer Seeks Advice on Radiation Therapy

I am 81 yrs, suffering from prostate cancer since last 6/7 months. I had earlier multiple health issues like Type 2 Diabetes (2yrs), Alzheimer's, Parkinsons plus, I have also heart issues with two stents inserted in 2014. I follow a very sedate lifestyle with walking for 45-55 mts + physical exercise 30 mts almost each day. I have been able to contain Alzheimer's and Parkinson's to almost 85-90% level and check Diabetes with food habits and walking to almost 70-75% level. . From 212 FPBS t has come down to 111 and PPBS currently is 78. I am focusing on prostate cancer. I wish to give some data for your reference: PSA- Total- from 4.14 it has come down to 1.89 Testosterone- from 585 it has come down to 0.660 reading of 20/05/24 I am strictly following my Urologists instructions so far. I am under his treatment for last 6/7 months. But he advices me to go in for MRI based Radiation therapy at HYD. I am extremely averse to any type of radiation therapy as the cells apparently are in sleeping mode with hormonal therapies but once I go in for radiation even if 85% cells die the balance surviving cells will attack my system vigorously and age will not be able to withstand their attack. Can I continue with hormonal therapies? Your advice please