50 y. psa @ 3.9 up from 2.2. no symptoms are other than back/hip ache. no family hx. one mri read had pi-rad 3 w/2.8 cm lesion. then read by others with 2 pi-rad 5, 2 pi-rad 4, and 1 pi-rad 3. biopsy has been done. why different mri reads? im worried?

This discrepancy in the MRI should be addressed with your urologist. It must be explained to you as simplified as possible, and a decision on treatment depending on the biopsy results should be made in conjunction with you and your doctor as to the types of treatment offered and their risks. Due to your rather young age, this decision should be given top priority.