Home>Prostate Ultrasound Imaging
Ultrasound - Based Prostate Cancer Smart Screening Analysis
Considering Prostate Ultrasound? | Before prostate cancer biopsy: analyze your PSA trend, use new screening technology and consider smart screening strategy analysis.
Transrectal ultrasound (TRUS) imaging of the prostate measures prostate volume and can reveal abnormal areas that raise suspicions of prostate cancer.
Ultrasound imaging is a crucial step in the most effective prostate cancer screening strategy. Typically, ultrasound comes after an elevated PSA, then after enhanced test blood testing (Free PSA, Prostate Health Index [PHI] or 4Kscore) and before MRI screening or a prostate biopsy.
Learn more about Prostate Smart Screening for Cancer at our home page in a new window
Take Next Steps Based on Your Smart Screening Strategy
- Interpret your elevated PSA and prostate volume measured by ultrasound.
- Interpret your ultrasound results (prostate volume and suspicion) and PHI.
- Ultrasound: Crucial step in the most effective prostate cancer screening strategy.
- Learn about transrectal ultrasound (TRUS) imaging of your prostate.
- Develop Prostate Smart screening strategy for your elevated PSA.
1. Interpret Your Elevated PSA and Prostate Volume Measured by Ultrasound
The probability of prostate cancer:
- Increases as PSA increases to elevated levels.
- Increases as prostate volume decreases to small sizes measured by ultrasound.
What Is the Probability of High Grade or Significant Cancer for Elevated PSA Levels?
The highly regarded ERSPC Risk Calculator estimates the probability of significant prostate cancer (mostly high-grade and some large low-grade) and the probability of any prostate cancer, as discussed in Sections 6 and 7 below with a range of results presented in Section 11 below. There you will learn of the many factors that affect the probability of prostate cancer.
Here, we focus on two of the most important factors, PSA level and prostate volume, for men with no other risk factors. The graph on the right plots the probability significant prostate cancer will be found by biopsy as a function of elevated PSA levels for three prostate volumes estimated by digital rectal exam (DRE) or measured more accurately by transrectal ultrasound imaging of the prostate: small (25cc), medium (40cc) and large (60cc).
Notice for each prostate volume curve that the probability of significant prostate cancer increases as PSA increases to elevated levels at the right.
Notice that the probabilities are much higher for a small prostate (the top red curve) than for a large prostate (the bottom blue curve). The probability of cancer is lower for large prostates because they tend to produce more PSA that "explains" elevated levels of PSA.
The dramatic difference in risk for small and large prostates demonstrates why it is so important to consider prostate volume for elevated PSA levels. For example, the risk level of 6% is the same at 10.0 PSA for a large prostate as at 3.0 PSA for a small prostate.
Ask your physician to estimate your prostate volume by digital rectal exam (DRE). Ask for a transrectal ultrasound (TRUS) to measure your prostate volume more accurately before considering a biopsy.
Why Does the Probability of Prostate Cancer Increase as PSA Increases?
There are many non-cancer causes of elevated PSA including prostate enlargement, as described in Section 10 below.
However, in the absence of prostate cancer the number of men with a given PSA level decreases steeply as PSA increases to elevated levels. For example, many men without prostate cancer have a PSA of 1.0, few men have a PSA of 5.0 and very few men have a PSA of 10.0.
In contrast, for men with prostate cancer the number of men with a given PSA level decreases more gradually as PSA increases to elevated levels, partly because larger tumors produce higher levels of PSA.
Therefore, the ratio of men with prostate cancer to men without prostate cancer increases as PSA increases, which translates into an increasing probability of prostate cancer as PSA increases to elevated levels.
Why Does the Probability of Prostate Cancer Increase as Prostate Volume Decreases?
Large prostates tend to produce higher levels of PSA, which can explain elevated PSA. Therefore, for an elevated PSA the probability of prostate cancer is lower for large prostates measured by ultrasound.
In contrast, small prostates tend to produce lower levels of PSA, which often does not explain elevated PSA. Therefore, for an elevated PSA the probability of prostate cancer is higher for small prostates measured by ultrasound.
2. Interpret Your Ultrasound Results (Prostate Volume and Suspicions) and PHI
Ultrasound prostate volume and suspicion level and the Prostate Health Index (PHI) cause large changes in the probability of prostate cancer, as shown on the graphs below.
What Is the Probability of High Grade or Significant Cancer for Elevated PSA Levels?
We continue to use the highly regarded ERSPC Risk Calculator to estimate the probability of significant prostate cancer (mostly high-grade and some large low-grade).
Here, we take a different look at two of the most important factors, prostate volume and PSA level, for men with no other risk factors. The graph on the right plots the probability significant prostate cancer will be found by biopsy as a function of prostate volumes measured by ultrasound for three elevated PSA levels: 3.0, 6.0 and 9.0.
Notice for each PSA curve that the probability of significant prostate cancer decreases as prostate volume increases to large volumes.
The probabilities are much higher for small prostates (at the left) than for large prostates (at the right). The probability of cancer is lower for large prostates because they tend to produce more PSA that "explains" elevated levels of PSA.
The dramatic difference in risk for small and large prostates demonstrates why it is so important to consider prostate volume measured by ultrasound for elevated PSA levels. For example, the risk level of 5% is the same at 9.0 PSA for a large (60cc) prostate as at 3.0 PSA for a very small (20cc) prostate.
What Is the Probability of High Grade or Significant Cancer for an Abnormal Ultrasound?
Here, we focus on the two important factors produced by ultrasound imaging, ultrasound cancer suspicion level and ultrasound prostate volume, for men with PSA 6.0 and no other risk factors. The graph on the right plots the probability significant prostate cancer will be found by biopsy as a function of prostate volumes measured by ultrasound for a normal and an abnormal image that raises with suspicion.
Notice that an abnormal ultrasound triples the probability of significant prostate cancer at a typical prostate volume of 40cc from 5% to 15%.
After an abnormal ultrasound, a screening MRI would be the next step for a smart prostate cancer screening strategy.
An abnormal ultrasound with hypoechoic lesion visible is discussed in Section 3 below.
What Is the Probability of High Grade or Significant Cancer for Elevated Prostate Health Index (PHI) Levels?
The Prostate Health Index (PHI) incorporates three blood tests to improve prostate cancer screening significantly compared to PSA alone. After an elevated PSA, PHI can be the next step prior to ultrasound imaging for a smart prostate cancer screening strategy.
The ERSPC Risk Calculator allows us to analyze the combined effects of PHI and prostate volume measured by ultrasound. For an elevated 3.0 PSA level, the graph on the right plots the probability significant prostate cancer will be found by biopsy as a function of prostate volumes measured by ultrasound for three PHI levels: 5, 20 and 40.
Notice for each PHI curve that the probability of significant prostate cancer decreases as prostate volume increases to large volumes measured by ultrasound.
3. Ultrasound: Crucial Step in the Most Effective Prostate Cancer Screening Strategy
Transrectal ultrasound (TRUS) imaging of the prostate is a crucial step in the most effective prostate cancer screening strategy, as introduced in Section 5 below. Skipping ultrasound imaging or any other crucial step increases the risk of poor decisions: either late diagnosis or premature biopsy and diagnosis with the risk of impotence and incontinence.
Use PSA for Early Warning then Prostate Health Index (PHI) or 4Kscore Blood Tests
PSA testing provides early warning of prostate conditions and possible cancer at low cost with no negative consequences if used as part of a smart screening strategy for prostate cancer. See our Elevated PSA and High PSA pages in new windows.
The Prostate Health Index (PHI) blood test provides valuable information and is an appropriate next step after an elevated PSA. It can be low cost (about $100) and is often reimbursable. The 4Kscore blood test is an alternative. We focus on PHI because it is much lower cost than 4Kscore ($595), more often reimbursed and somewhat more effective when used with the ERSP Risk Calculator because 4Kscore does not consider prostate volume or ultrasound suspicions. The Free PSA blood test provides valuable information and is a component of both PHI and 4Kscore.
PCA3 is a urine test that provide useful information.
Use Transrectal Ultrasound (TRUS) Imaging of the Prostate Next if PHI Is Elevated Enough
Transrectal ultrasound (TRUS) of the prostate provides valuable additional information and is an appropriate next step if PSA and PHI are elevated enough. Ultrasound is higher cost than PHI and often reimbursable. Prices of ultrasound can vary with $600 typical. The cost of ultrasound imaging is typically less than prostate biopsies that are guided by transrectal ultrasound (TRUS), which start at about $600 and may reach $1,000 or more. Reimbursement is often possible because ultrasound can be justified for a variety of medical conditions from prostate enlargement to prostate cancer.
Use Ultrasound before Screening MRI because of Cost and Consequences
A Screening MRI (multi-parametric MR imaging of the prostate) should follow ultrasound imaging in a smart screening strategy. A screening MRI provides the most valuable information at the highest cost with reimbursement difficult and substantial potential consequences. Cost at academic and research centers can be $3,000 and may reach $10,000 or more. However, some centers offer screening MRI for as low as $600 but quality and effectiveness can vary dramatically. Reimbursement is increasingly difficult as health insurance providers resist paying.
Choosing a screening MRI is a major decision because it can be costly and starts a process that is hard to control. It is impossible to undo the decision after your MRI is evaluated. At that point, the medical process will tend to sweep you along if you receive a high MRI suspicion score [4 or 5] or even a moderate suspicion score . A high or even a moderate suspicion score will lead to very strong pressure to biopsy. Choose MRI screening only when you are comfortable proceeding to a subsequent biopsy.
Ultrasound imaging is a valuable and relatively low-cost way to gain more control over your MRI decision process and make better decisions. For example, you may feel comfortable delaying an MRI if your risks decrease because your prostate volume is moderate to large with no abnormal areas. Alternatively, you may feel more comfortable choosing an MRI if your risks increase because your prostate volume is small and/or there is an abnormal area.
Ultrasound before a screening MRI helps you make the best possible decision in light of your risks and risk preferences and may help justify reimbursement of your MRI costs when you are ready. For example, a suspicious abnormal area on ultrasound images may help convince your health insurance provider to reimburse a screening MRI.
Use Ultrasound before Biopsy because of Consequences
After shopping for the most cost effective screening MRI supplier, you may decide to skip a screening MRI and proceed to a prostate biopsy. A biopsy decision is high stakes because a premature biopsy has the risk of deadly sepsis with possible diagnosis and potential treatment and side effects such as impotence and incontinence before you are ready. Learn more about a Conventional Pattern Biopsy or MRI Targeted Biopsy in a new window.
Ultrasound before a biopsy helps you make the best possible decision in light of your risks and risk preferences.
Skipping ultrasound imaging or any other crucial step increases the risk of poor decisions: either late diagnosis or premature biopsy and diagnosis with the risk of impotence and incontinence.
Time and Effort to Operate the ERSPC Risk Calculator Can Be a Barrier to Use of Ultrasound Results
As a practical matter, full use of ultrasound results requires operation of the highly regarded ERSPC Risk Calculator:
If you are concerned about operating the ERSPC Risk Calculator, we encourage you to enlist the help of a daughter, son, spouse or friend or even pay a student with computer skills.
Alternatively, we can operate the ERSPC Risk Calculator for you and create a full smart prostate cancer screening strategy report for you. Learn more about Prostate Smart Screening for Cancer at our home page in a new window or read Sections 5, 6, 7, 8 and 9 below first.
Ultrasound Prostate Volume Significantly Increases Prostate Cancer Screening Performance
The four graphs above show how important prostate volume is to prostate cancer risk assessment. Respected studies in medical journals have shown the effectiveness of prostate volume for prostate cancer screening, which reinforces the high value of ultrasound imaging.
Two prominent prostate cancer risk calculators to assess elevated PSA are available at no charge on the Internet:
A 2016 British Journal of Urology International multi-institutional Irish study shows that the ERSPC-RC significantly outperforms the PCPT-RC in the prediction of prostate cancer (PubMed abstract in a new window). A 2012 World Journal of Urology very large European and US multi-institutional study shows the importance of prostate volume in the ERSPC-RC for screening effectiveness (PubMed abstract in a new window).
The improvement using prostate volume appears to account for the difference in performance between the ERSPC-RC and PCPT-RC, which does not consider prostate volume. The A 2016 British Journal of Urology International study, above, also shows the additional significant improvement in the ERSPC-RC when the Prostate Health Index (PHI) is considered.
Ultrasound Prostate Cancer Suspicion Results (Normal or Abnormal) Are Valuable
As you saw on a graph above, transrectal ultrasound (TRUS) imaging provides valuable information about possible abnormal areas of your prostate that can strongly affect estimates of your cancer risk by the ERSPC Risk Calculator.
The ESPC-RC says that “Transrectal ultrasound (TRUS) allows the visualization of the prostate. The evaluation may show abnormalities, that may be related to several conditions, such as prostatitis, BPH or prostate cancer. Abnormal is defined as a hypoechoic lesion.” A hypoechoic lesion is an abnormal area that can be seen during an ultrasound examination because it is darker than the surrounding tissue.
A new 2017 Journal of Urology UC San Francisco study of ultrasound lesion visibility found that use of hypoechoic lesions was very effective at identifying significant prostate cancer, defined as high-grade (Gleason score >= 3+4), and nearly as effective as multi-parametric MR imaging. Older studies suggest that ultrasound imaging effectiveness increases for the larger prostate cancer tumors that are most deadly.
This study reinforces the high value of using transrectal ultrasound (TRUS) to look for abnormalities that may be significant prostate cancer, in addition to the high value of measuring prostate volume. Skipping ultrasound imaging increases the risk of poor decisions: either late diagnosis or premature biopsy and diagnosis with the risk of impotence and incontinence.
Finally, a suspicious abnormality on prostate ultrasound images may encourage you to consider a screening MRI and help justify MRI reimbursement by your health insurance provider.
4. Learn about Transrectal Ultrasound (TRUS) Imaging of Your Prostate
Transrectal ultrasound (TRUS) imaging of the prostate is used for prostate cancer screening, as described above, and to assess other prostate conditions, including prostate enlargement caused by benign prostatic hyperplasia (BPH). The ultrasound procedure also may be called prostate sonography.
What Is Transrectal Ultrasound (TRUS) Imaging of the Prostate?
Transrectal ultrasound (TRUS) imaging of the prostate uses sound waves emitted and received from a probe in your rectum to capture images of your prostate, which is next to your rectum.
What Does a Transrectal Ultrasound (TRUS) Probe Look Like?
How Does Ultrasound Imaging of the Prostate Work?
Ultrasound imaging is similar to sonar used by submarines to locate ships and by bats to detect and avoid objects. Ultrasound refers to high frequency sound waves that we can't hear. The sound waves are produced by the probe, or transducer, and radiate outward until they encounter a barrier, such as the edge of an organ or tumor. Some of the sound wave energy reflects off the barrier back to the probe. As for a submarine, the time the sound takes to reach the barrier and return after reflection allows estimation of distance. Reflection times and other aspects of the reflected sound waves are captured and converted to images by computer software.
What Equipment Is Used for Transrectal Ultrasound Imaging of the Prostate?
What Are the Risks of the Transrectal Ultrasound (TRUS) Imaging Procedure?
For most men, there are no major risks to using transracial ultrasound (TRUS) imaging.
There is no radiation risk because sound waves are used for imaging rather than radiation.
Men with an allergy to latex require special precautions because the probe is usually covered with a latex sleave.
Excessive stool in the rectum degrades the images. An enema may be needed prior to the procedure.
How to Prepare for a Transrectal Ultrasound (TRUS) Imaging Procedure?
Very little preparation is needed for a transrectal ultrasound (TRUS) imaging procedure. There usually are no restrictions on eating or drinking. A small enema may required because excessive stool in the rectum reduces image quality. As always, paperwork must be filled out, possibly including a consent form. An allergy to latex should be noted because a latex sleeve is used to cover the probe, unless an allergy exists.
What Happens During a Transrectal Ultrasound (TRUS) Imaging Procedure?
You will be given a gown to wear after you remove clothing and jewelry.
On the exam table, you will lie on your side with your knees bent up to your chest.
A digital rectal exam (DRE) may be performed first.
A disposable cover is placed on the probe, which is then lubricated with gel.
The probe is inserted through your anus into your rectum without pain, but your rectum may feel full. The gel may feel cool and wet. The probe is inserted in the rectum because the prostate is next to it in your body.
The radiologist will rotate the probe to scan all of the prostate and surrounding tissue while watching real-time images. You may hear a "whoosh, whoosh" of blood flow if doppler ultrasound is used.
Periodically, images are captured for evaluation, and sometimes video is recorded.
Some discomfort may be caused by your holding a still position throughout the procedure.
Finally, images are transferred to the radiologist for evaluation, including measurement of prostate volume and assessment of any abnormalities with emphasis on hypechoic lesions.
How Is Prostate Volume Measured from Transrectal Ultrasound (TRUS) Images?
Radiologists use ultrasound images to measure three gland dimensions: the maximum length (L), the maximal height orthogonal to the length (H), and the maximal width (W).
Several formulas have been developed to measure prostate volume. Most commonly used is the ellipsoid formula, which is:
How Are Abnormal Hypoechoic Lesions Identified on Transrectal Ultrasound Images?
The radiologist looks for hypoechoic lesions which are abnormal areas that can be seen on ultrasound images because they are darker than the surrounding tissue.
What Is a Transrectal Ultrasound (TRUS) Guided Pattern Biopsy for Prostate Cancer?
A conventional pattern biopsy usually uses real-time transrectal ultrasound (TRUS) imaging to guide injection of small hollow needles through the rectum wall to the prostate. Sometimes a conventional pattern biopsy is called a random biopsy because the needles encounter prostate cancer by chance without any targeting. The physician uses a special prostate biopsy "gun" to inject the needles from the rectum into the prostate. The needles collect a small amount of prostate tissue in their hollow cores for removal and later evaluation for prostate cancer by a pathologist. The real-time transrectal ultrasound (TRUS) helps the physician inject often 12 or more needles into the prostate in a pattern that "randomly" samples most areas of the prostate in the hopes of capturing prostate cancer cells if they are present.
What Is an MRI Targeted Fusion Biopsy Guided by Transrectal Ultrasound (TRUS)?
MR imaging (multi-parametric MRI) is reasonably effective at identifying the highest risk prostate cancers that are both high-grade and moderate to very large. Please see our Prostate MRI page in a new window. High risk prostate cancers are often visible on multi-parametric MR images of the prostate. For targeted biopsies, new technology "fuses" real-time ultrasound with previously obtained MR images that allow injection of needles through the "targets" identified by MRI and guided by the fused real-time ultrasound images.
MRI targeted fusion biopsies are more effective than conventional pattern random biopsies without targeting.
What Is High Intensity Focused Ultrasound (HIFU) Treatment of Prostate Cancer?
High-intensity focused ultrasound (HIFU) is a new targeted way of treating prostate cancer tumors without damaging the rest of the prostate and surrounding tissue. High-intensity ultrasound is sequentially focused on a prostate tumor and adjacent tissue until the tumor and surrounding tissue are destroyed. Reduced side effects are the primary benefits of HIFU, but treatment effectiveness has not fully established. HIFU has been used throughout the world for prostate cancer treatment, and now two systems have been approved by the US Food and Drug Administration (FDA). HIFU uses the results of an MRI targeted fusion biopsy to identify the tumor targets for focal therapy. Real-time MRI fusion ultrasound is used to guide the physicians application of HIGU energy to destroy tissue.
5. Develop Your Prostate Smart Screening Strategy for Elevated or High PSA
For men who want to lead a collaborative team effort rather than be a passive patient.
Prostate Smart analysis helps you create your strategy with your collaborative team of physicians and confidants to minimize your risks of:
> Regrettably late diagnosis of deadly cancer:
> Premature biopsy, diagnosis, treatment and side effects:
Analysis is needed to create the best personal screening strategy for you because:
We analyze published studies and present the implications for personal decisions. Studies are from: Mayo Clinic, Cleveland Clinic, Johns Hopkins, Memorial Sloan Kettering, NIH, NYU, UCLA, UC London, Yale and more.
Learn more about PSA-Based Prostate Smart Screening Strategy Analysis in a new window.
Return to Prostate Smart Screening for Cancer home page.