Thanks everybody for extra information and discussion about this topic. We were never offered any PET CT before this latest biopsy where 4+3 was discovered in one biopsy core. My husband had only PSMA MRI as part of surveillance and only one biopsy in 10 years of surveillance. IMHO once gleason is discovered transperineal biopsy should be offered to patient every 2-3 years since 3+3 can progress to 4+3 with ductal involvement without much change of PSA . That is what happened to my husband. If we had a chance to discover 3+4 we would have insisted on doing treatment at that point and not wait any longer. At this point we got referral to do PSMA PET CT but I found information (by reading tons of papers) that it is good idea to have PSMA PET MRI also since the first one scans whole body including bones and PSMA PET MRI is more specific for soft tissue and tissues and organs surrounding prostate which PSMA PET CT might miss.
Please if anybody has different information correct me - I am still learning and I am overwhelmed at this point.
Facilities that offer PSMA PET MRI are not available everywhere though, it is for some reason rare to have that option. Luckily we have one center in SF and we are now trying to get referral for that too. For many patients with very early stages and non ductal involvement it might not be so important but since my husband has one plug with ductal involvement I think it would be extremely helpful to have one. So little research done about IDC since it is rare entity *ughhhhh Like it is not enough that we have 4+3 but it had to be something extra possibly dangerous and obscure on top of that and with little info and not many specific options for his case at the same time (!?). It sucks big time...