by Trevor A. Flood, MD FRCPC
August 25, 2023
High grade prostatic intraepithelial neoplasia (HG-PIN) is a non-cancerous condition that starts in the prostate gland. In this condition, abnormal cells fill the small glands and ducts in the prostate. A similar condition called low-grade PIN also exists but it should not appear in pathology reports as it has been shown to have no clinical significance.
No, HG-PIN is not a type of prostate cancer. As a result, definitive treatment, such as surgery or radiation therapy, is not required for patients with HG-PIN.
The diagnosis of HG-PIN is made after tissue from the prostate is examined under the microscope by a pathologist. The abnormal cells in HG-PIN are located in the glands and ducts of the prostate. Unlike cancer cells, the abnormal cells in HG-PIN are still separated from the surrounding tissue by a thin barrier. When viewed under the microscope, the abnormal cells are larger than normal prostate cells, their nuclei (the part of the cell that holds the genetic material of the cell) are hyperchromatic (darker), and prominent round structures called nucleoli can be seen in the center of the nucleus.
Some medical studies have suggested that the presence of HG-PIN is associated with an increased risk of developing prostate cancer. However, HG-PIN does not always progress to prostate cancer and the likelihood of it progressing to cancer is much less than it was once thought.
Experts are divided as to what type of medical follow-up is recommended when HG-PIN is detected on biopsy. It is generally accepted that other factors should be evaluated when determining when and if a repeat biopsy should be performed. Talk to your doctor to determine the management strategy that is best for you.