Hi cjeff and welcome to the Forum! In terms of risk, your Gleason 7 (both 4+3 and 3+4)
with tertiary* (or focal) pattern 5, is considered to be
Grade Group IV by some researchers (for example see Table 3
here). This will be academic if your PSA becomes and remains undetectable, but, coupled with your pT3b staging, does mean you and your docs will be paying very close attention to your test results.
As you know, PSA is a fairly crude diagnostic tool for PCa in men with prostates, but after a RP it becomes an exquisite indicator of any remaining healthy and/or malignant tissue. When PSA persists after surgery, adjuvant therapy is usually recommended after a healing period. Just how much PSA qualifies as "persistent PSA" is a matter of debate, but you can discuss this with your docs.
Wishing you the very best for a lifetime of undetectable readings!
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* When Gleason pattern 5 accounts for a small amount of the cancer (usually <5%), it is listed as a tertiary 5 after the primary and secondary patterns. The three score that may have tertiary 5 are 3+4, 4+3, and 4+4.
Djin