What Most Doctors Don't Tell You About Genetic Testing for Prostate Cancer

A physician’s perspective on what prostate cancer genetic tests reveal, what they miss, and how the results should influence screening and treatment decisions.

By Stephen Petteruti, DO 

Board-Certified Family Physician | Founder, Intellectual Medicine | Last reviewed August 2026

Genetic testing is an increasingly prominent topic in prostate cancer care. Each year, more men are encouraged to consider it, often with the expectation that results will provide definitive answers about their risk, cancer aggressiveness, and treatment options.

It is reassuring to believe that a single laboratory test could address these concerns.

However, this is not the case.

A common mistake in prostate cancer care is seeking certainty where it does not exist. This pattern has occurred with PSA testing and prostate biopsies, and is now emerging with genetic testing. Placing excessive confidence in a single test overlooks the complexity of each individual patient.

This does not diminish the value of genetic testing, which has an important role. The issue arises when it is expected to answer questions beyond its intended scope.

Understanding What Genetic Testing Actually Measures

When most men hear the phrase "genetic testing," they assume it is looking for cancer. That's not actually what these tests are designed to do. Most genetic testing for prostate cancer looks for inherited mutations that may increase your lifetime risk of developing the disease or influence how it behaves if it develops. These inherited mutations, known as germline mutations, are present from birth and can be passed from one generation to the next. They are entirely different from the mutations that occur within cancer cells after a cancer has already formed.

Over the past decade, researchers have identified several genes that appear to influence prostate cancer risk, including BRCA2, BRCA1, ATM, CHEK2, PALB2, HOXB13, and the Lynch syndrome genes. Men who carry some of these mutations have a higher likelihood of developing prostate cancer, and certain mutations are associated with cancers that behave more aggressively. Those are meaningful findings, and they have changed how we think about hereditary prostate cancer.

What they have not done is provide certainty. A positive genetic test does not tell you when cancer will develop, whether it will ever become life-threatening, or whether immediate treatment is the right decision. Likewise, a negative genetic test does not guarantee that you will never develop prostate cancer. Genetic testing is one piece of information, and often a valuable one, but it should always be interpreted alongside your PSA trend, MRI findings, family history, overall health, and the larger clinical picture. Like every other test we use in prostate cancer, it answers some questions while leaving others unanswered.

A Gene Is Not Your Destiny

I frequently discuss with patients the distinction between risk and certainty. These concepts are not interchangeable, though they are often treated as such.

Take a BRCA2 mutation as an example. We know from the research that men who carry this mutation have a higher lifetime risk of developing prostate cancer, and if cancer does develop, it is more likely to behave aggressively than in men without the mutation. That information is valuable because it helps us understand risk and determine who may benefit from closer monitoring.

However, it does not predict individual outcomes.

A positive genetic test cannot determine when prostate cancer will develop, its clinical significance, or its potential threat to your life. It also does not indicate that immediate surgery, radiation, or aggressive treatment is necessary. These decisions require a comprehensive evaluation of the full clinical context, not just the presence of a genetic mutation.

Conversely, a negative genetic test should not create a false sense of security. Men without identifiable inherited mutations can still develop aggressive prostate cancer. Genetics estimates probability but cannot account for all factors influencing disease development or behavior.

For this reason, I advise against relying too heavily on any single test. Genetic testing provides valuable information, but it is only one part of the assessment. A comprehensive understanding of risk requires integrating PSA trends, MRI findings, metabolic health, hormone status, family history, lifestyle, and overall health. Focusing on one aspect rarely provides the complete picture.

The Conversation Should Never Stop With One Test

A central theme of this book is that no single test should determine your future. Whether it is a PSA, MRI, biopsy, or genetic test, each provides useful information but does not offer a complete picture. Allowing one abnormal result to dominate the discussion can lead to fear rather than informed decision-making.

When meeting with a patient diagnosed with prostate cancer, I consider more than laboratory or pathology results. I review PSA trends, MRI findings, metabolic health, body composition, inflammation, hormone status, family history, symptoms, and overall health. Most importantly, I seek to understand the patient's goals and priorities.

For many men, priorities extend beyond laboratory values. Preserving strength, energy, independence, sexual health, and the ability to enjoy life with loved ones are central concerns. These factors should guide treatment decisions, with the goal of maintaining both longevity and quality of life.

Who Should Consider Genetic Testing?

A common misconception is that every man with an elevated PSA should undergo genetic testing. Current evidence and clinical guidelines do not support this approach. Genetic testing is most effective when used for appropriate indications and at the right time.

Today, genetic testing is generally recommended for men with metastatic prostate cancer, men with high-risk or very high-risk disease, those with a strong family history of prostate, breast, ovarian, pancreatic, or colorectal cancer, and individuals from families known to carry hereditary cancer syndromes.³ In these situations, the results may affect treatment decisions, identify patients who could benefit from targeted therapies, or supply valuable information for family members who may also be at increased risk.

Not every man with an elevated PSA requires genetic testing. An elevated PSA is one data point, not a diagnosis. Before ordering further tests, it is important to consider whether the results will meaningfully influence clinical decisions. If not, additional testing may increase uncertainty rather than provide clarity.

Medicine can fall into the trap of ordering tests simply because they are available. Information is valuable only when it informs better decisions. The focus should be on identifying which data are most relevant to the individual patient.

The Family Conversation

An often-overlooked aspect of genetic testing is its implications for family members. Unlike PSA or MRI findings, inherited genetic mutations may also affect children, siblings, and other close relatives.

If you are found to carry a mutation such as BRCA2 or one of the Lynch syndrome genes, that information may allow family members to pursue appropriate screening, genetic counseling, or earlier surveillance if they choose.¹ In many cases, helping future generations better understand their own cancer risk becomes one of the greatest benefits of genetic testing.

Genetic testing is unique in its potential to affect entire families, not just individual patients. Its value may extend beyond treatment decisions by enabling loved ones to make informed choices about their own health.

What Genetic Testing Cannot Tell You

Despite its value, the limitations of genetic testing are often underemphasized. Like all medical tests, it provides some answers but leaves many questions unresolved.

A genetic test cannot tell you whether your cancer will spread. It cannot tell you when, or even if, your cancer will ever become life-threatening. It cannot tell you that surgery, radiation, or hormone therapy is automatically the right decision, nor can it predict whether the benefits of treatment will outweigh the possible effects on your strength, energy, sexual health, independence, or overall quality of life.

These decisions require careful clinical judgment, including a review of PSA trends, MRI findings, overall health, and personal priorities. No laboratory test can replace this comprehensive discussion. Genetic testing is most valuable when it informs, rather than concludes, the conversation.

A common error in modern medicine is assuming that more information always leads to better decisions. Better outcomes result from understanding the significance and limitations of data and integrating it into the broader clinical context. This approach distinguishes thoughtful, individualized care from mere data collection.

My Perspective

To clarify my position, I am not opposed to genetic testing. When used appropriately, it can provide valuable information. The error lies in assuming that any single test, regardless of its sophistication, offers all the answers.

Medicine has become increasingly reliant on numbers, biomarkers, imaging, pathology reports, and genetic panels. While each tool provides significant information, none should replace clinical judgment, physician experience, or open discussions about patient priorities.

Too often, a single abnormal result becomes the sole focus of discussion, whether it is an elevated PSA, a suspicious MRI, a biopsy finding, or a genetic mutation. This shift can lead to treating the test result rather than the patient.

The most important questions are whether information will change clinical decisions, improve longevity, or preserve strength, vitality, independence, sexual health, and quality of life. These outcomes should remain central to every treatment discussion.

This philosophy guides Fight Cancer Like a Man. It emphasizes using available tools wisely, understanding their strengths and limitations, and making decisions that protect both longevity and quality of life.

Want to Learn More? 

If this article challenged the way you've been thinking about prostate cancer, you're exactly why I wrote Fight Cancer Like a Man.

In the book, I explain why I believe too many men are rushed into life-changing decisions before fully understanding the evidence, the tradeoffs, and the alternatives. My goal isn't to tell you what decision to make. It's to help you ask better questions so you can make the right decision for yourself.

If you're looking for personalized guidance, I also offer consultations where we review your complete medical history, laboratory results, imaging, and overall health to help you better understand your options.

Whether you read the book, schedule a consultation, or continue learning through these articles and podcasts, my hope is the same: that you make every decision from a place of knowledge rather than fear.