Sugar and PSA levels

I was diagnosed with prostate cancer about six years ago when my psa was appx 4, with a Gleeson score of 6. I decided to go on 'surveillance' without treatment. My psa has steadily increased, but I have kept a close watch on my diet and the rise and fall of psa levels. My levels are at 14 now, but the cancer is still within the prostate. I am lining up for Brachytherapy. But what I have noticed in those six years of 'surveillance' is that restricting sugar seems to lower my psa levels (stops the rise of it). I have also been taking vit D3 (8000iu) and K2 tablet). It's going to be interesting to see my psa levels before my next appointment with my oncologist in two months. Any other experiences similar?