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Understanding your prostate pathology report

Posted By Harvard Prostate Knowledge On March 10, 2009 @ 2:29 pm In Diagnosis,Prostate Knowledge,Screening | Comments Disabled

At least initially, the pathology report is one of the most important factors in the management of your prostate health, especially if you have been diagnosed with cancer. For example, it can provide valuable information about the location and extent of the cancer, thus helping your physician decide whether to recommend active surveillance, hormone treatment, radiation therapy, or surgery.

With that in mind, you might think that preparing and reading a pathology report would be straightforward — but unfortunately the opposite is true. Pathology reports are not prepared uniformly (compare Figures 3 and 4, below, for example). In fact, they can vary considerably even within a single institution. They may not be labeled thoroughly or contain enough specifics for you and your doctor to make a good treatment decision.

At the same time, the information that is included in the report may be difficult to decipher. You may also get conflicting interpretations depending on how the report was prepared and who is reading it. It is entirely possible for two pathologists to look at the same biopsy slides and yet disagree about whether you have cancer! (For more information about this, read the article “Why pathologists may disagree.”)

In this article you will learn what your pathology report should include and how to make sense of the information it contains. Other articles on this site explain when to get a second opinion about the pathology report and why it is sometimes necessary to have a repeat biopsy, as well as what questions to ask to obtain the information you need to decide which treatment is best for you.

Deconstructing the report

It is always a good idea to request a copy of your pathology report. A thorough reading will give you the information you need to have informed discussions with your urologist, surgeon, and oncologist, and better guide any decisions you need to make about what to do next.

If the findings on the pathology report are abnormal, it is likely that the diagnosis will fall into one of three major categories:

  1. An atypical finding
  2. High-grade PIN
  3. Prostate cancer (adenocarcinoma).*
*Note: Although there are other, rare forms of cancer that can arise in the prostate gland, this article will focus on the most common type, adenocarcinoma.

An atypical finding means that the pathologist cannot confirm or rule out cancer. Sometimes this finding is reported as “suggestive of” or “suspicious for” cancer but not diagnostic of cancer. This frustratingly equivocal diagnosis usually means that the pathologist looked at the tissue on the slides and saw cells that were not typical, but they were not abnormal enough to classify as cancer (see “What makes it cancer?”).

What makes it cancer?

Although PSA levels or a digital rectal exam may hint at cancer, only a pathologist looking at cells in tissue samples can make the diagnosis. The following are among the key features they look for:

  • Proliferation of relatively uniform small glands lined by a single layer of cells
  • Cells with prominent nucleoli, components of the nucleus that help build proteins
  • Enlarged nuclei
  • Lack of basal cells, which sit below the epithelium in normal tissue
  • Cells that stain readily with dyes
  • Evidence of perineural invasion (PNI).

There is no consensus about the correct terminology to use for such lesions. Often you’ll see the term atypical small acinar proliferation, or ASAP, but it could also be labeled atypical hyperplasia, atypia, atypical glands, or focal glandular atypia.

Fortunately, such atypical findings are reported in only about 8% of pathology reports, according to a review of 39 studies involving needle biopsy specimens. But the trend toward doing more biopsies and finding smaller cancers has led to an increase in atypical diagnoses. Studies have shown that nearly half of the men who receive such an atypical diagnosis initially will find they have prostate cancer during a follow-up biopsy. This happens regardless of PSA levels or results of a digital rectal exam (DRE), which appear to be unrelated. In addition, compared to other pathologic diagnoses, atypical findings have the highest likelihood of being changed on expert review, usually to a diagnosis of cancer.

High-grade PIN, short for prostatic intraepithelial neoplasia, is another broad diagnostic category. This finding involves a subjective reading of the pathology slides and also generates debate about follow-up and treatment. It is now thought that high-grade PIN might increase a man’s risk of developing cancer, but because the steps involved in cancer progression are still elusive, the degree of risk remains unclear. It is usually not considered an important factor when associated with a definitive diagnosis of cancer.

Beyond these basic distinctions, and sometimes even within them, things can get hazy. The pathologist weighs numerous complex factors when making these broad diagnostic statements, and if you have been given a prostate cancer diagnosis, the report usually contains descriptive information about the type, amount, and grade of cancer found. All of these factors can affect risks and influence treatment decisions.

For all these reasons, your pathology report is not something you should skim but rather scrutinize. It is important to understand every component, discuss how the pathologist arrived at his or her conclusions (or lack thereof), and share the details with every physician involved in your care. The major components of a good pathology report are reviewed here briefly.

Gleason score

If your biopsy finds cancer, the first piece of information you’ll want to note is the Gleason score. This numerical value grades prostate tumor cells according to how they look compared with normal cells and how mutated they appear under a microscope, a quality known as differentiation. (Normal cells are well differentiated and cancer cells are not.) Because tumors often consist of multiple cell types, the pathologist assigns two values between 1 and 5: the first to the predominant cell type, and the second to the next-most-prevalent cell type (see Figure 1). The sum, ranging from 2 to 10, is the Gleason score; the higher the number, the more aggressive the cancer.

Figure 1: The Gleason score

The Gleason score is a numerical value that grades prostate tumor cells according to how they appear compared to normal prostate cells (a quality known as differentiation). Because tumors often consist of multiple types of cells, the pathologist assigns two values: the first to the predominant cell type, and the second to the next-most-prevalent cell type. These two values are added to come up with the Gleason score.

Well differentiated

  1. Glandular cells are small, of fairly uniform shape, and tightly packed together.
  2. Cells display more varied and irregular shapes and are loosely packed.

Moderately differentiated

  1. Cells are even more irregular in size and shape and are more dispersed; some cells are fused, and cell borders are less distinct.

Poorly differentiated

  1. Many cells are fused into irregular masses; some cells (see those darkly shaded) have begun to invade the connective tissue that separates cells.
  2. Most of the tumor consists of irregular masses that have invaded the connective tissue.

The Gleason score is one of the most important factors in determining whether the cancer is likely confined to the prostate and how aggressive it is (see Table 1 for a quick guide to what the scores mean).

Table 1: Gleason score risk assessments

Total Gleason score Simple risk assessment Points to consider when assessing risk
2 to 4 Lower risk
  • Total Gleason scores of 2 to 4 are rare. Less than 2% of men who undergo a prostate biopsy have a score in this range.
  • Pay attention to the first value assigned, as this is based on the preponderant area of cancer. That is why a Gleason score of 7 has a worse prognosis if it is based on the values 4 + 3 than if it is based on the values 3 + 4.
  • Most cancers detected as a result of PSA screening are Gleason 6 (3 + 3) or 7 (3 + 4).
5 to 6

7 (if 3 + 4)

Moderate risk
7 (if 4 + 3)

8 to 10

Higher risk

Number of cores

An ideal report also specifies how many samples, or cores, were removed during the biopsy. The standard number of cores used to be six: three from the right side of the prostate and three from the left. However, this limited sampling meant that cancerous portions of the prostate, if there were any, might be missed. As a result, as many as one in four patients eventually diagnosed with prostate cancer was told, on the basis of the initial biopsy, that he did not have cancer — meaning that the test provided a false-negative finding.

Today, most doctors agree that an initial biopsy should include at least 10 to 12 core samples. In certain situations, some doctors recommend doing a saturation biopsy, which typically removes 12 to 14 cores — and sometimes as many as 20 or more — but less agreement exists about this practice.

Anatomic location

Ideally, the pathologist who prepares your report will have separated and labeled the core samples according to what part of the prostate they came from. This labeling will tell you and your doctors whether the cells came from the right or left side and whether they were drawn from the apex (counterintuitively, at the bottom), mid zone (middle), or base (top) of the prostate. In a saturation biopsy you may see even more detailed labels, such as RMA and RMB to differentiate between the right mid zone near the apex and the right mid zone closer to the base. Similarly, the report may refer to three zones: the peripheral, central, and transition zones (see Figure 2). All of this information can be invaluable in helping to determine the general location of the tumor, which helps guide treatment decisions.

Figure 2: Zones of the prostate

To help your doctor more precisely determine the location of prostate cancer or another condition, such as high-grade PIN, your pathology report may name specific areas. For example, it may refer to the apex, located at the bottom of the prostate; the base, at the top; or the mid zone, the area between the apex and base. Alternatively, it may note three zones: the peripheral zone (1), the central zone (2), and the transition zone (3). Seventy percent of prostate cancers arise in the peripheral zone. Few arise in the anterior prostate.

Extent of cancer

In addition to paying attention to the number of cores taken, you’ll want to look at how much cancer was found. This information may be provided as the number of positive cores, the length of cancer in millimeters among all cores, the percentage of cancer per core, the fraction of positive cores, or the total percentage of cancer in the entire specimen. Regardless of the type of measurement, your doctor can use this information to determine the likelihood that the cancer is confined to the prostate or has spread.

Clinical data

In the clinical portion of the report, you may see notes from your physician to the pathologist offering any relevant information about why the biopsy was performed and what the physician is looking for.

Gross description

Your pathology report should also include a gross description with such important identifying information as the container in which the tissue was shipped to the department, length of various pieces of tissue, their color, and how the tissue is labeled.

Don’t be alarmed if you see mention of rectal or colonic tissue. Small fragments of bowel lining (colonic mucosa) are common in needle core biopsy specimens since the needle has to poke through this tissue to get to the prostate.


Sometimes, you will find notes to your physician or urologist in a section labeled “Comments.” This may be an important source of additional information such as whether the pathologist has found high-grade PIN or any atypical tissue. This section may also describe various features of the tissue and offer clues about the pathologist’s thinking, especially if the final diagnosis is not entirely clear.

Identifying details

Last, the report should include identifying information such as your name, age, and patient number, and the date, as well as the name and signature of the pathologist who prepared the report, the name of the person who performed the biopsy, and the name and address of the laboratory.

Figure 3: An ideal pathology report

City Hospital
Department of Pathology
123 Main Street
One City, Anystate USA


Patient Name: John Doe

Medical Record #: 01020304

Date of Birth: 04/01/26 (Age: 81) Sex: Male

Procedure performed by: Dr. I. M. Best

Specimen #: S00-9999

Procedure date: 07/15/07

Report date: 07/16/07

Gross description by: Dr. Eagle Eye


Prostate needle biopsies: 21

A) R5A: Fibromuscular tissue only; no prostatic epithelium seen.

B) R5MA: Atypical glandular focus suspicious for adenocarcinoma.

C) R5M: No malignancy identified.

D) R5MB: No malignancy identified.

E) R5B: No malignancy identified; focal chronic inflammation.

F) R4A: No malignancy identified.

G) R4MA: No malignancy identified; focal chronic inflammation.

H) R4M: No malignancy identified.

I) R4MB: No malignancy identified.

J) R4B: No malignancy identified; focal chronic inflammation.

K) L5A: Fibromuscular tissue and colonic mucosa; no prostatic epithelium seen.

L) L5MA: Adenocarcinoma, Gleason score 7 (3 + 4), involving 50% of core.

M) L5M: Adenocarcinoma, Gleason score 8 (4 + 4), involving 70% of core.

N) L5MB: Adenocarcinoma, Gleason score 8 (4 + 4), involving 80% of core.

O) L5B: Adenocarcinoma, Gleason score 8 (4 + 4), involving 80% of core.

P) L4A: No malignancy identified.

Q) L4MA: Adenocarcinoma, Gleason score 7 (4 + 3), involving 80% of core.

R) L4M: Adenocarcinoma, Gleason score 8 (4 + 4), involving 80% of core.

S) L4MB: Adenocarcinoma, Gleason score 8 (4 + 4), involving 80% of core.

T) L4B: Adenocarcinoma, Gleason score 8 (4 + 4), involving 70% of core.

U) L seminal vesicle: Seminal vesicle, no malignancy identified.

Note: Perineural invasion is seen. Focally, a tertiary Gleason 5 pattern is noted.

Clinical Data: None given.

Gross Description: Received in 21 formalin containers labeled with the patient’s name, “John Doe,” the medical record number, and additionally labeled “R5 apex,” “R5 mid-apex,” “R5 mid,” “R5 mid base,” “R5 base,” “R4 apex,” “R4 mid apex,” “R4 mid,” “R4 mid base,” “R4 base,” “L5 apex,” “L5 mid apex,” “L5 mid,” “L5 mid base,” “L5 base,” “L4 apex,” “L4 mid apex,” “L4 mid,” “L4 mid base,” “L4 base,” and “left seminal vesicle” are multiple prostate cores measuring up to 2.5 cm, entirely submitted in cassettes A–U respectively.

Report Electronically Signed Out — Eagle Eye, M.D. 07/16/07

Figure 4: A less-than-helpful pathology report

State Hospital
Department of Pathology
123 Elm Street
Another City, Anystate USA


Patient Name: John Doe

Medical Record #: 01234567

Date of Birth: 04/01/26 Age: 81

Sex: Male

Specimen #: S2007-X123

Procedure date: 06/11/07

Report date: 06/12/07

Gross description by: Dr. I.M. Brief


Prostate needle biopsies:

#2, right prostate: Adenocarcinoma, Gleason score 3 + 3 = 6, present in <5% of one of seven cores

Clinical Data: Prostate cancer.

Gross Description: Received from outside institution — three (3) H & E stained glass slides labeled “S2007-X123” and sub-labeled “2-1,” “2-3,” and “2-5” from procedure dated 06/11/07.

Originally published Oct. 1, 2007; last reviewed April 27, 2011.

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