Fundamentals Required for Prostate Cancer Staging

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For prostate cancer patients, an optimal treatment plan is the most important factor for long-term survival, and finding that ideal treatment begins with accurate staging. The Prostate Cancer Research Institute (PCRI) offers many resources to help patients determine and understand their stage. They divide patients into five stages, assigning each to a different shade of Blue—Sky, Teal, Azure, Indigo or Royal.

The stage is ascertained by answering an eight-question quiz related to various factors—PSA, biopsy, scans, and digital rectal examination—that are found in the medical chart. A link to the PCRI’s quiz is on the PCRI home page at pcri.org.

The Medical Chart

There is no need for a patient to be bashful about asking his doctor for a copy of the medical chart. Patients have every right to their records, and having that information on-hand can help them better understand their cancer, determine their stage, and select an appropriate treatment plan. Some offices may charge a nominal fee, and it may even be necessary to request the information from more than one office to compile all the necessary information. Once the patient has a copy of his medical chart, he will see that it is divided up into sections labeled laboratory, pathology, progress notes, and radiology. In these sections patients will find the specific information needed to determine their stage:

Laboratory

After the patient obtains the chart, he should create a chronological history of all PSA levels. For the quiz, the highest PSA is entered. The only exception would be an abnormally elevated PSA due to prostate trauma. For example, PSA levels will remain elevated for two months after a needle biopsy.

PSA can also be artificially elevated for 24 hours or so after a digital rectal exam or after sexual activity. Another factor is the testosterone level in the blood. Sometimes elderly men with low testosterone levels, say less than 100, will have an artificially suppressed PSA. If a testosterone test has not been done, patients should mention it to their doctors at the time of the next blood test. Ultimately, if none of the above caveats apply, one should use the highest PSA when calculating the cancer’s stage.

Pathology

The biopsy report is kept in the pathology section of the chart. A random prostate biopsy may include anywhere from six to 20 or more biopsy cores. Information from the biopsy is divided into three independent categories. One category is related to the cancer’s grade, called the Gleason score. The other two are related to the amount of cancer found. Let’s cover the amount issue first:

  • The total number of cores that contain cancer provides a sense of the tumor’s size. For example, having a total of four cancerous cores out of a total of six cores suggests that a fairly good-sized tumor is present, since more than half of the cores contain cancer. On the other hand, another example would be to have a total of two cancerous cores out of a total of 20 cores, which would suggest that the tumor is relatively small.
  • It’s also important to consider how much cancer is present within each biopsy core. Knowing the percentage of cancerous tissue in a core helps to determine the extent of the tumor (meaning how the cancer is growing and spreading). A pathologist who looks at the core with a microscope can judge how much of the core is replaced with cancer and how much of the core contains normal prostate gland tissue. This information can be reported in two ways: First, it can be presented as a total number of millimeters of cancer (1 to 18, with 18 representing the entire core’s length). Alternatively, the amount of cancer in the core can be reported as a percentage of the total core. Typically, the pathology report conveys this information as both a percentage and as a total number of millimeters. So the extent of the cancer can be understood both by the total number of cores containing cancer and by how much cancer each core contains, as expressed in millimeters or as a percentage.
  • When people think of a prostate biopsy, the Gleason score, which reflects the cancer’s grade, is usually the first thing that comes to mind, and that is the correct mindset. Grade reflects how abnormal the cancer cells appear, and it is far more important than the size of the tumor. For example, it is much better to have a very large grade 6 tumor than a very small grade 10 tumor.

The Gleason grading system was designed many years ago, and, as a result, it has its quirks. For example, the lowest score is 6 and the highest is 10. A Gleason score that is reported as 6 will be written as 3+3=6. A Gleason nine will be written as 4+5=9 or as 5+4=9. If the biopsy contains several different scores, the highest score from the report is the one that should be entered into the quiz.

Stage

Description

T1 or  “A”

T1c: Tumor cannot be felt by digital rectal examination

T2 or “B”

Tumor confined within the prostate

T2a: Tumor  felt by DRE but less than half of one lobe

T2b: Unilateral tumor felt by DRE involving more than half of one lobe 

T2c: Bilateral tumor felt in both lobes

T3 or “C”

Tumor felt by DRE that extends through the prostate capsule

T3a: Extracapsular extension

T3b: Tumor felt by DRE that invades seminal vesicle(s)

T4

Tumor felt by DRE that invades rectum or bladder

 

Progress Notes

The results from the finger exam of the prostate, called the digital rectal examination, or “DRE”, is termed the clinical stage or the T stage. Somewhere in the progress notes, usually in the area marked “Physical Examination,” the doctor will record whether he felt any nodule and, if so, the relative dimensions of the nodule. The system of notation that doctors use to record their findings in the chart is presented in the table below. To answer the quiz you will need to know your T stage.

Radiology Reports (Imaging Studies)

An explanation of any imaging the patient has had will be found in the Radiology section of the chart. These reports are written by a radiologist, a specialist devoted to reading scans. The most important information contained in a radiology report is summarized in a section titled “Impression.” For the purpose of the quiz, the most important facts to be gleaned from a prostate MRI report are the presence of one or more of the following: extracapsular extension, seminal vesicle invasion, or lymph node spread.

Other scans, usually a bone scan or a CT scan of the abdomen and pelvis (to look for enlarged lymph nodes), may be performed, especially in men whose PSA levels are above 10 or whose Gleason score is above 6. When the CT or bone scan shows metastatic cancer, it is important to note the location of the metastases and, whether the metastases are exclusively in the pelvic lymph nodes or in some other area of the body. A new scan called Axumin uses positron emission tomography (PET) and is much more accurate than a CT scan. As things stand presently, Axumin is only FDA-approved in the evaluation of men who have relapsing disease (a rising PSA) after surgery or radiation.

Any Previous Treatment for Prostate Cancer?

The last factor to be considered when taking the PCRI’s staging quiz is whether there has been any previous treatment for prostate cancer. Men who have undergone previous therapy with surgery, radiation, cryotherapy, or hormone blockade who are now dealing with a rising PSA generally have a more aggressive type of prostate cancer and are thus assigned to a different stage. However, it is not always crystal clear what exactly constitutes a cancer relapse. A rising PSA is generally an accurate indicator, but patients need to become familiar with some of a relapsing cancer’s subtleties.

A PSA Rise After Surgery

Monitoring PSA after surgery is relatively straightforward. The PSA, after all, is expected to be zero once the prostate gland has been entirely removed. However, total surgical removal of the gland is not easy and small amounts of the prostate may be left behind. When that occurs, PSA may hover indefinitely in the 0.1 to 0.3 range, even when there is no cancer. Men with these very low levels of PSA after surgery can consider foregoing immediate treatment and monitoring their PSA closely to see if there is an upward trend. Treatment can be withheld if the PSA remains stable. The longer the PSA remains stable, the more likely the PSA is due to persistent prostate gland tissue rather than cancer.

A PSA Rise After Radiation

Monitoring PSA after radiation can be challenging. As a rough starting point, consider a PSA elevation above 1.0 to be “abnormal.” But there are exceptions. It is possible to have a PSA above 1.0 and still be cancer-free. Noncancerous PSA elevations actually occur rather frequently after radiation, particularly after seed radiation. These elevations are called a “PSA bounce.” A bounce is believed to result from radiation-induced prostate inflammation, i.e., prostatitis. With a bounce, the main priority is to distinguish it from a cancer relapse. The most reliable way to do this is to examine a continuous graph of multiple PSA levels that have been checked over time. PSA from recurrent cancer tends to manifest as a smooth, unbroken, upward progression. Since a bounce is caused by inflammation, these PSA levels tend to wax and wane, oscillating up and down on a graph in a zig-zag, spiking pattern.

Monitoring Hormonal Therapy

Hormone resistance is defined as a rising PSA despite low testosterone levels in the blood. PSA levels should be reviewed at the onset of hormone therapy and on an ongoing basis. Detecting resistance to hormone blockade is relatively easy since the PSA should always decline to less than 0.1 within 6 to 8 months of starting hormone blockade. If this fails to occur, it usually means that the PSA will start rising in the near future.

Conclusion

As you consider your various treatment options, you should review your medical chart and complete the PCRI’s quiz to determine your cancer’s stage. Understanding how assigning a stage to your own cancer will gird you with the necessary insight to choose the ideal treatment plan and improve your odds for an optimal quality of life and maximal survival.