Question: What is high-grade PIN (prostatic intraepithelial neoplasia)?
Answer: High-grade prostatic intraepithelial neoplasia, or high-grade PIN, is a pathologic reading, something that the pathologist might see on a needle biopsy or on a prostate that's been surgically removed.
Now this is thought to be what we call dysplastic. It is not normal prostate tissue, it is not cancerous tissue. We believe, we don't know for certain, but we believe and have some evidence that prostatic intraepithelial neoplasia, if left alone, will actually progress to be frank prostate cancer.
So, one can think of it as pre-cancer or something that is destined to become cancer. Individuals who have high grade PIN on biopsy need to be watched very carefully because they are very likely over the next several years to actually have prostate cancer.
We are looking of actually ways of treating high grade PIN in an effort to cause the patient to not develop prostate cancer, to actually try to stop the progression of that tissue from normal cancer. But for right now, high-grade PIN is a marker for increased risk for ultimately being diagnosed with prostate cancer.