Evaluate PSA with Imaging, Not Random Biopsy

Avoiding Unnecessary Radical Treatment

Prostate cancer is the most common form of cancer in men.  While some types of prostate cancer are life-threatening, some types are not.  Recent media reports have focused on concerns about men undergoing unnecessary radical treatment with the low-grade forms of the prostate cancer.  PSA screening has been blamed for this overtreatment.  The real culprit, however, is the 12-core random needle biopsy, a popular office procedure performed by urologists over a million times annually.

Problems with the Random Biopsy 
Low-grade prostate cancer is a completely harmless entity that never spreads outside of the prostate gland.  It is so prevalent in men over 50, that a random biopsy finds this type of prostate cancer 20% of the time, even when the PSA is normal.  Every year random biopsy diagnoses over a 100,000 men with low-grade disease.  Sadly, more than half of these men end up treated with unnecessary surgery or radiation. 

Over diagnosis of low-grade prostate cancer is not the only problem.  Random biopsy needles are passed through the rectal wall and can cause infections serious enough to result in hospitalization.   Random biopsy has also been implicated as a cause for erectile dysfunction.  

Imaging is “Blind” to Low-Grade Cancers
Previously doctors regarded all types of prostate cancer as universally dangerous, so prostate imaging was deemed inadequate because it is prone to miss the harmless, low-grade lesions we have been talking about.

 However, now that we know that only larger, high-grade lesions are potentially dangerous, imaging makes perfect sense.  It is actually beneficial to patients that imaging fails to detect to low-grade lesions.  

Imaging is the mainstay of cancer detection for other common cancers such as breast cancer and lung cancer.

 Breast cancer is screened with mammography. Lung cancer screening for men who are smokers is done annually with a CT scan.  In regards to the prostate there are two types of prostate imaging to consider: High-resolution color Doppler ultrasound and 3 Tesla multiparametric MRI (MP-MRI).

Color Doppler Ultrasound Imaging
Color Doppler ultrasound scanning of the prostate is performed by a physician. It is actually two scans in one:  Standard grey scale imaging and color Doppler imaging to detect areas of increased blood flow.  From a cancer screening viewpoint, color Doppler ultrasounds can report three different outcomes: 1) Completely clear;  2) An overtly suspicious lesion is detected or 3) An ambiguous lesion(s) are detected.

When to Biopsy Ambiguous Lesions
Expert judgment, attention to the individual patient characteristics, and patient to physician dialogue are factors that are considered when trying to determine if a targeted biopsy is necessary. Color Doppler ultrasound imaging detects all sorts of things including scar tissue, areas of active prostatitis, and nodular areas from BPH.

 Sometimes, sequential monitoring with a follow-up scan in six months, to see if a lesion shows further growth may be preferred to an immediate biopsy.  

There are specific lesion characteristics that tend to raise greater concern:  A location in the peripheral zone of the prostate, lesions over a centimeter in diameter, lesions that bulge the prostate capsule, and lesions that have increased blood flow.  A targeted biopsy is advised more frequently in men who are younger and in men whose PSA levels are higher than they “should be” relative to the size of their prostate, a condition termed a high PSA density.

Targeted Rather than Random Biopsies
When an overtly suspicious lesion is detected, a targeted biopsy (a limited number of cores aimed directly at the lesion) is typically recommended. Lesions that are biopsy-negative or show low-grade cancer are monitored.  When the biopsy diagnoses high-grade disease expert counseling is followed by appropriate treatment. 

“Cross Checking” Ambiguous Lesions with MP-MRI
Color Doppler ultrasound and MP-MRI are complementary. In our experience the imaging findings match 80% of the time.  However in a minority of cases, one imaging modality will substantially illuminate a specific lesion more clearly.  Therefore, in ambiguous cases, a combination of both modalities increases confidence that high-grade cancer isn’t being overlooked.  Doing a second imaging procedure with a MP-MRI is usually preferable to doing an immediate biopsy.  If subsequently a targeted biopsy is deemed necessary, the additional imaging information obtained from a MP-MRI may further increase the accuracy of the targeted biopsy.

Color Doppler for Monitoring Low-Grade Cancer
These days experts advise men with low-grade prostate cancer to forgo surgery or radiation and monitor their condition with Active Surveillance.  The most common physician protocol is regular PSA testing and periodic random biopsy.  However, multiple random biopsies are associated with discomfort and progressive risk of serious infections and impotence.  Sequential monitoring with color Doppler ultrasound to determine if small lesions are growing or stable is a far more logical approach than subjecting men to repeated biopsies.

Final Thoughts
Men with an elevated PSA who initially undergo a color Doppler ultrasound rather than a random biopsy can be spared a biopsy if their scan is clear.  Men who require a biopsy will need far fewer cores because the biopsy is targeted to a specific lesion within the gland.  Men on Active Surveillance are also candidates for monitoring with Color Doppler Ultrasound to determine if there is any progressive disease. 

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