I agree strongly with the suggestion that you get a second opinion on the biopsy from Dr. Epstein at JH.
With regard to perineural invasion (PNI), the majority of studies (but not all) I've seen concluded that PNI
seen after surgery is not remarkable. I remember one study that found that more than 80% of men who opted for surgery had PNI somewhere in their prostates afterwards.
On the other hand, PNI
seen at biopsy is correlated with adverse findings. This study found the rate of PNI
found at biopsy to be between 7.0% to 33.0% in nearly 15,000 patients:
Impact of biopsy perineural invasion on the outcomes of patients who underwent radical prostatectomy: a systematic review and meta-analysis (Review, 2019)
"
Conclusion: Evidence from the included observational studies indicated that biopsy PNI was not only correlated with adverse pathologic characteristics but also with worse BCR prognosis of local PCa after RP. The status of biopsy PNI could serve as a promising risk-stratification factor to help the decision-making process, considering active surveillance (AS) or further treatment for PCa patients."
I don't have the Full Text, but my understanding is based on the fact that prostate cancer has an affinity for invading the fine nerves within the prostate (and may be a pathway for spreading out of it). PCa has often been growing for some time before diagnosis and it's reasonable to expect that when the entire prostate is sampled and examined microscopically, PNI will be found
somewhere. If it is seen anywhere in any amount, it scores as PNI+ in the post-RP report.
However, a biopsy samples a minute amount of prostate tissue, and if PNI is observed, you could infer that it may be widespread within prostate and that the cancer is more likely to have been growing longer, and/or is, perhaps, more aggressive.
Keep in mind that these studies are statistical in nature, and just up the risk factor for adverse findings (if one were to choose surgery, where the whole prostate is sampled). They do not mean that everyone with PNI at biopsy will have adverse findings or go on to biochemical recurrence (a future rise in PSA after primary treatment that may signal clinical recurrence).
You can discuss this finding with his doctors: they may be of a different opinion or, if they agree that the PNI does have significance, it could factor into weighing treatment options.
You can also confirm with his doctor that the 17-core biopsy was not "target-only," but rather sampled all 12 prostate zones, with some
extra cores in some identified targets. Was this your husband's first biopsy? What prompted it and was there a prior MRI?
You might discuss the advantage of having a genomic test (such as OncotypeDx or Decipher) done on the biopsy tissue, especially if Dr. Epstein grades the biopsy as a (3+4) or a (4+3). Here too, knowing whether the risk of metastases within 5 years is low, intermediate, or high might also weigh on treatment options.
Djin