If you’re scheduled for a prostate biopsy, your doctor is likely testing a tumor for cancer. During this outpatient procedure, tissue will be removed from the tumor using a needle. It will then be analyzed by a pathologist, a doctor who reviews the results of the biopsy and provides information about the findings. The results of your biopsy are provided in a pathology report.
Your oncologist or urologist will use the pathology report as a key piece of information in determining if cancer is present and the stage, based on the cell structure in the tumor. It will also play a key role in determining whether treatment is needed at this time.
What Is Included in a Prostate Cancer Pathology Report?
The pathology report provides a general description of the sample size, the area of the tumor it was taken from, and a general conclusion of what was found. This section of the report includes:
- A description of how the tissue appears to the pathologist without the aid of a microscope. This includes the sample size and weight, and the appearance and color of the tissue.
- A Gleason Score which is a system of describing and rating how the cancer cells look under a microscope. A higher rating is an important predictor of the cancer’s aggressiveness (likelihood of growing and spreading). A complete explanation about the Gleason Score is found below.
- The number of core biopsy samples taken, if more than one. The core samples are taken when a needle is passed into the tumor and tissue is removed. The pathologist records the number of samples and the location of extraction. The locations where the samples are taken from are:
- The apex which is the area of the prostate that is located farthest from the bladder.
- The mid-zone which is the middle of the prostate gland.
- The base which is the area of the prostate closest to the bladder.
Potential Findings of a Prostate Pathology Report
After the pathologist examines the prostate tissue samples, a conclusion will be drawn. Following is an explanation and description of possible findings.
Benign Prostate Tissue
The most hoped-for conclusion is that the tumor is benign. Any findings beginning with benign and followed with prostate tissue, prostate glands or prostatic hyperplasia mean no cancer was found in the tissue sample. However, other conclusions may be drawn from this including:
- Benign prostatic hyperplasia is an indication of the prostate gland enlargement which can be caused by an over-abundance of prostate cells. Commonly, this happens in older men and it is not cancer.
- If your oncologist still suspects cancer based on other findings from a rectal exam or blood test results, the doctor may order another biopsy in the future to see if the cancer has progressed.
- Another benign finding may be acute or chronic inflammation of the prostate. This condition may increase PSA levels (detected in a blood test), but does not indicate cancer.
- Other non-cancerous terms that may be on the report are:
- Shrinkage of prostate tissue is called atrophy.
- Shrinkage of the entire prostate is called diffuse atrophy.
- Shrinkage of a certain area is focal atrophy.
- Adenosis which shows benign changes in the gland.
When the pathologist sees cells under the microscope that are not typical, (atypical or suspicious of cancer) they might not conclude that cancer is not present. Caution is taken and the oncologist may order a second biopsy in a few months. Additionally, urine, blood, and imaging tests may be ordered.
- A report stating “low-grade prostatic intraepithelial neoplasia is present means the cells look to be mostly normal.
- If the findings say “high-grade prostatic intraepithelial neoplasia,” the pathologist will conclude that the cells are precancerous. These cells may become cancer over time. However, this indicates less risk for cancer than the “atypical or suspicious of cancer” conclusion.
- Ninety-five percent of prostate cancer is classified as adenocarcinoma, and whether the cancer is this type or another type will be listed on the report.
- If the pathologist finds cancer cells, they will be graded with the Gleason System to determine severity.
What Does the Gleason Score Mean?
The Gleason Score is an indicator of how aggressive the prostate cancer may be. The pathologist will identify the primary pattern (most common cell type) and the secondary pattern (next most common cell type) and those cells are given a grade. The Gleason System uses numbers from 1 to 5.
- Grade 1 means the cancerous tissue is close to normal.
- Grades 2 through 4 show the cancerous tissue is between normal and very abnormal.
- Grade 5 means the cancerous tissue and the pattern of growth are very abnormal.
The primary and secondary cell pattern are graded independently, and the two grades are added to find the final Gleason Sum. A report might indicate the tumor is graded 2+4=6. The first number, in this case 2, is reflective of the majority of the cells. The second number, in this case 4, reflects the second most seen cells. The highest rating that can the Gleason Sum can be is 10.
The Gleason Score will indicate the potential behavior of a cancerous tumor and will be used by the oncologist to decide on the plan for treatment. However, the doctor will also take into consideration other factors such as rectal exam results, PSA level (detected in a blood test), MRI findings, and whether the cancer has spread beyond the prostate.
Related reading: Dig deeper into what the Gleason Score is and what it means.