liquid biopsy usage

sizzle

Does anyone have any color on the use of liquid biopsies (e.g. ExoDx IntelliScore) to grade PC post an initial positive needle biopsy? According to my research this technology is not yet accepted pending additional research and testing. I am currently being monitored at MSK under their active surveillance  protocol. My PSA is currently at 5.8 with a doubling time of 4.3 years. I suffered some minor complications from the initial biopsy that confirmed the existence of gleason 6 PC and would like to avoid subsequent biopsies if possible. Thanks for any feedback.

VascodaGama

There is no substitute to biopsies at present times

Sizzle,

I understand your wish in avoiding repeated biopsies required in the AS regimen but any other procedure, at use today to diagnose cancer, is just a predictive tool that separates those with high probability in having cancer from those of low probability in having it. In your case you were diagnosed positive already so any further diagnosis wouldn't be required. The AS regimen requires periodical exams including biopsies to verify any progress of the disease or clinical stage, A repeated biopsy can identify newer areas found with cancer (as well as grading tumors) making it a voluminous case but the initial grade of an established tumor doesn't evolve from low to high grade. The regimen doesn't try finding if the Gleason grade 3 has changed to grade 4. The newer biopsy could pinch this time another tumor of higher grade, leading you straight to stop AS and start thinking on a treatment.

Tests based on genetics (including the biomarkers in ExoDx test) have been introduced in the diagnosis process to further subdivide those at risk of high grade prostate cancer from those at low risk (or those that would not respond well to hormonal manipulations (ADT independent) in the future. Some use the biopsy tissues and some the urine or even blood samples. Sophisticated Image studies in multi parametric approaches have also been used to predict cancer or aggressivity but these, as far as I know, do not substitute a biopsy in confirming the presence and grade of the cancer. You can take it as an add-on to the diagnosis but not as a definite result.

In your shoes I would discuss with your doctor in spanning the period of biopsies, if appropriate in your case.

Best,

VG