What is PIN?
Sometimes the results of a prostate biopsy will come back to the doctor with no signs of cancer but show something called prostatic intraepithelial neoplasia (PIN). This is a tiny lesion, or wound, in the prostate tissue that experts believe sets the stage for the development of prostate cancer within about ten years for some, but not all men. (Bostwick 2004) PIN seems to appear in men as early as in their 20’s and almost 50% of men have some form of PIN by the time they are 50. PIN is considered a pre-cancerous state (Bostwick 2004); it is not prostate cancer or a cancerous tumor but the cells are distinctively different from normal prostate cancer cells. It does not spread to other tissues, as cancer, nor does it trigger a significant increase in PSA or cause any symptoms.
Treatment for PIN
PIN is rated as low or high grade, based on how abnormal the cells are under the microscope. If you have low-grade PIN and you want to try to prevent it from graduating to high-grade, or if you already have high-grade PIN, you have several options. A recent study showed that taking the drug Proscar (finasteride) reduces the risk of developing high-grade PIN, (Thomson 2007), and other drugs are also being tested. Some studies also indicate that exercise reduces the risk of developing prostate cancer, and a 2009 study that involved laboratory animals showed that exercises reduces the risk of developing PIN and prostate cancer. (Esser 2009) Green tea has also been found to be effective in preventing high-grade PIN from progressing to cancer (Bettuzzi 2006).
Ultrasound Image of Prostate Needle Biopsy
If the PSA test or the DRE indicate that cancer may be present then the doctor may recommend biopsy. In a biopsy tissue samples are taken from the prostate gland and examined by a pathologist under a microscope who will look for abnormalities in the tissue architecture and cell structure. Well-differentiated cells are more normal in appearance while poorly differentiated cells are more abnormal in appearance. Generally speaking the more abnormal the cells appear the more aggressive the cancer. Some cells, although not cancerous, may be classified as high grade PIN, which may be an indicator of potential cancerous growth.