ADT leads to the death of prostate cancer cells. "Androgen withdrawal triggers the programmed cell death pathway in both normal prostate glandular epithelia and androgen-dependent prostate cancer cells."... from: https://pubmed.ncbi.nlm.nih.gov/8602401/#:~:text=Within%20the%20prostate%2C%20androgens%20are,androgen%2Ddependent%20prostate%20cancer%20cells.

So 8 months of ADT could/should eliminate active cancer cells thruout the body.

Question: what was the Gleason score of the tumor removed at surgery? The same as before ADT? If so, I'd say the surgery was needed to finish the job the ADT started.