We never stop learning, here. I'd never heard of a 'simple' prostatectomy.

A simple prostatectomy is a surgical procedure to remove the inner part of a severely enlarged prostate, treating benign prostatic hyperplasia (BPH) by leaving the outer prostate capsule intact. This surgery improves urinary symptoms by removing the tissue that blocks urine flow, often using a minimally invasive robotic approach through small incisions. It is different from a radical prostatectomy, which removes the entire prostate, typically for cancer.

Good information right here:
https://www.bidmc.org/centers-and-departments/urology/urologic-procedures-traditional-and-minimally-invasive/prostate-urologic-procedures/enlarged-prostate-open-surgical-resection-simple-prostatectomy