I've been taking fenben off and on since my PC returned in April 2019 (I’ve never had metastases.). I’ve had 4 HIFUS total in Europe: beginning in 2008 - I don’t remember the exact years, but the last one was in 2015, and each one was preceded by a raised PSA and positive biopsy.
Here are my results:
Prior to Nov. 2018: generally between 0.6 and 0.9 following my last HIFU in 2015
Nov. 2018: 0.9
April 2019: 1.8
May 2019: 2.27 - urologist says PC has returned; no biopsy; Axumin and MRI scans note "anomalous" activity in the midline suggesting recurrence, no metastases seen; begin fenbendazole (4 g) 3 days on 4 days off
June 2019: 1.8 - continue FZ 4g 3on/4off
July 2019: 1.5 - continue FZ 4g 3on/4 off
September 2019 - 1.99 (anxiety level rises) - continue FZ 4g now daily
October 2019 - 1.5/Free PSA 8% (sigh of relief) - continue FZ, reduce dosage to 1g or 2g (whatever I could get), sometimes daily, sometimes M-F, sometimes every other day (essentially 3on/4off)
November 2019: 1.5/Free PSA 7% (sigh of relief II) - continue FZ, 1-2g, M-F
I’m not sure of the value of testing free PSA when total PSA is below 4.0 - I’ve never read any studies or recommendations for calculating free PSA when total is below 4.0. But when I was first diagnosed, the free PSA was 6% and total was 8.8 (a one-month doubling), and my Gleason score was 4+3, later modified to 3+4.