Replies to post #5465 on BioCurex, Inc.(fka BOCX)

[Gold Seeker]

"announced today that its RECAF cancer test detects initial stages of prostate cancer with 75% sensitivity and 100% specificity when compared to healthy individuals; and 68% sensitivity with 97% specificity when compared to men with benign prostate conditions.

Sensitivity is the ability of a test to detect existing cancers (if all patients who have a cancer test positive = 100% sensitivity).
Specificity represents how well the test avoids false positives (no false positives = 100% specificity)."

False positives occur primarily in men age 50 or older. In this age group, 15 of every 100 men will have elevated PSA levels (higher than 4 ng/ml). Of these 15 men, 12 (75%) will be false positives and only three will turn out to have cancer.
OK, take a group of 100 with no signs of an abnormal prostate that show an elevated PSA. The accuracy of the PSA test would indicate that about 75 of that number are false positives. So, you give that same group of 100 a RECAF test. With the 25 individuals that actually have cancer, RECAF would only confirm for sure that 19 of those have cancer. There are 6 men that actually have cancer with running RECAF at high specificity that do not show a positive RECAF test. You now have 81 men who have shown an elevated PSA and they do not know if they are one of the 6 who does have cancer. You are now in a group that has an 8% chance of having cancer. What do you do? Very muddy water.

Now take the case above of abnormal prostate. Again the group of 100. Under current protocol, the doctor would recommend that all of this group get a biopsy. I have not found the figures for false positives within this group but this group would definitely have a higher cancer rate because of the reduced performance figures shown above with RECAF but you still have men with cancer that do not show a positive RECAF level. Again, muddy water.

What I actually see is with the false negatives from the PSA test. RECAF should show some of those with cancer although that figure would be quite low. What I don't see is RECAF used as an effective tool in eliminating false positives with elevated PSA. The key is to eliminate an unnecessary biopsy. Will RECAF do that?