Category Archives: Men’s Health

Erectile dysfunction is the inability to get and/or keep an erection that is firm enough for sexual activities. Formerly called impotence, this problem affects up to 20 million men in the United States. Erectile dysfunction is more common in older men, but in many cases, the issue can be successfully treated (1).

What are the possible causes of erectile dysfunction?
Most cases of erectile dysfunction are due to physiological (physical health) factors, but psychological (mental) factors can be the cause in some men, as well as compounding the problem in men with underlying physiological causes (1).

Physical causes of erectile dysfunction include:

• Reduced blood flow to the penis, which may be due to atherosclerosis (hardened arteries), endothelial dysfunction (when blood vessels cannot vasodilate efficiently), and other heart diseases. For more information about atherosclerosis, see our previous article here.
• Inability to trap blood during an erection
• Issues with the nerve signals from the brain or spinal cord to the penis. These can be caused by stroke, seizures, multiple sclerosis, spinal cord injuries, and surgeries (2).
• Cancer treatments near the pelvis (e.g., for prostate, colon-rectal, or bladder cancer)
• Medications for other health problems
• Low testosterone (also associated with reduced libido (sex drive)). We offer several tests to measure your testosterone levels (see list in the bottom section of this page). For more information about the signs of low testosterone in males, see our previous article here. 
• Structural disorders of the penis (e.g., Peyronie disease)

What factors are associated with an increased risk of erectile dysfunction?

• Smoking
• Older age (over 50 years)
• Diabetes (erectile dysfunction is 3.5 x more common in diabetics compared to non-diabetics (3))
• High blood pressure
• Heart disease
• High cholesterol
• Obesity
• Drug use
• Excess alcohol consumption
• Lack of physical activity
• Prolonged perineal pressure (e.g., from bicycle riding)
• Depression
• Anxiety (particularly related to sexual performance)
• Stress

How can erectile dysfunction be treated?
The treatment for erectile dysfunction often starts by treating the underlying cause. For example, if you are also affected by high cholesterol, your doctor may suggest making dietary changes, increasing physical exercise, and considering statin medications to lower your cholesterol levels. Diabetics may require more frequent glucose testing to ensure they are maintaining a healthy blood glucose level. Treatment of emotional problems may also be required, such as counseling and medication for depression.

Treatments directly targeted at erectile dysfunction include:

• Oral drugs (e.g., Viagra)
• Testosterone therapy (if low testosterone is detected)
• Penile injections (can be self-administered with appropriate training)
• Intraurethral medication (tiny pill placed inside the urethra)
• Vacuum erection devices
• Penile implants
• Surgery to bypass penile artery damage

References:
1. Hirsch IH. (Modified July 2020). Erectile Dysfunction. Merck Manual Professional Version.
2. What is Erectile Dysfunction? (Updated June 2018). Urology Care Foundation.
3. Shindel AW & Lue TF. (2017). Sexual Dysfunction in Diabetes. Endotext [Internet].

Prostate cancer affects about 13 out of every 100 American men, and 2–3 of these men will die from prostate cancer. So there is a high chance that you know someone who has been affected. Maybe it was someone close to you or maybe you’re concerned about your own risk. There are many different factors that contribute to an increased risk of prostate cancer, some of which cannot be changed (e.g., age), while other factors can be changed (e.g., smoking).

What is prostate cancer?
Prostate cancer occurs when malignant cells start growing out of control in the prostate, a small gland that helps make semen. Prostate cancer can cause a range of symptoms, including difficulty urinating, frequent urination, painful urination and ejaculation, blood in the urine or semen, and pain in the back, hips, or pelvis (1). However, it is important to note that these symptoms can also be caused by other issues, such as benign prostatic hyperplasia and bacterial prostatitis. For more information about other possible causes of an enlarged prostate, see our previous article here.

What are the known risk factors for prostate cancer?

• Age is the most common risk factor for prostate cancer, with the chance of prostate cancer rising rapidly after 50 years of age. In fact, about 60% of prostate cancers are found in men over 60 years (2).
• Race/ethnicity affects the risk of prostate cancer. In America, prostate cancer is more common in African American men and in Caribbean men of African ancestry. In addition, it tends to appear at a younger age in these ethnicities. It is currently unknown why these risk differences are present (2).
• Where you live in the world also affects your risk, as prostate cancer is more common in North America, northwestern Europe, Australia, and on Caribbean islands. Again, the reasons for this increased risk are not clear, although lifestyle factors (e.g., diet) are thought to play a role (2).
• Genetic factors are associated with an increased risk, such as inherited variants in the BRCA1 and BRCA2 genes (which are more commonly known to increase the risk of breast cancer) (2).
• A family history of prostate cancer (e.g., affected brother or father) can more than double the risk, suggesting other inherited genetic factors play a role (2).

What other possible risk factors for prostate cancer are there?

• Dietary differences may play a role, as there appears to be a slightly higher risk in men who eat a lot of dairy products (2).
• Obesity may play a role, but studies have come to differing conclusions on the impact of body weight for the risk or prostate cancer (2).
• Smoking has been shown in some studies to influence the risk of prostate cancer, but other studies did not reach the same conclusions. However, there is increasing evidence that smoking can increase the risk of dying from prostate cancer (2).
• Chemical exposures may increase the risk of prostate cancer. However, further research is required to confirm these associations (2).
• Having a vasectomy may slightly increase the risk, but further research is required to confirm this (2).

What are ways to reduce the risk of prostate cancer?
Unfortunately, many of the risk factors for prostate cancer cannot be changed, and further research is required to confirm the risks associated with the modifiable risk factors. However, routine screening is still the most effective way to reduce the chance of serious or fatal complications from prostate cancer, especially because early prostate cancer (when it is easier to treat) doesn’t usually cause any symptoms (3).

Screening for prostate cancer may include a prostate specific antigen (PSA) test, such as the one offered here. Elevated PSA can be indicative of prostate cancer, but may also occur due to benign (non-cancerous) conditions. More info about PSA is available here.

Another screening option is a digital rectal examination (DRE) when a health care provider inserts a gloved, lubricated finger into the rectum to feel the prostate. However, this is not recommended as an initial screening method by the US Preventive Services Task Force (1).

If the PSA test and/or DRE are indicating prostate abnormalities, additional diagnostic tests can be conducted, including an ultrasound and a prostate biopsy. The biopsy involves the removal of prostate tissue for examination under a microscope to detect cancer cells (1).

How is prostate cancer treated?
Treatment options for prostate cancer vary depending on the cancer stage and if it has spread elsewhere in the body. If it is determined that the cancer is unlikely to grow quickly and there are no symptoms, no treatment may occur. Instead, the affected person is closely monitored with more frequent PSA tests and prostate biopsies (1).

Other treatment options include surgery to remove the prostate (as well as surrounding tissues if necessary) and radiation therapy to kill the cancer cells. There are also several treatment options currently undergoing investigation, including cryotherapy, chemotherapy, high-intensity focused ultrasound, and hormone therapy (1).

References:
1. Prostate Cancer, Basic Information. (Reviewed August 2021). CDC.
2. Prostate Cancer Risk Factors. (Revised June 2020). American Cancer Society.
3. What is Prostate Cancer? (Revised August 2019). American Cancer Society.

What is estrogen?
Estrogen is traditionally considered a female sex hormone but is actually a critical hormone in males too. Just as testosterone, considered a male sex hormone, is also important in females.

The strongest of the three estrogen hormones is called estradiol (also known as oestradiol and E2). Estradiol is especially important for male sexuality and must stay in balance with testosterone to control libido, erectile function, and sperm production (1). See our previous article here for more information about estradiol.

What are the roles of estrogen in males?
Estrogen plays important functions in the:

• Male reproductive system
• Skeletal system
• Skin health
• Nervous system
• Cardiovascular system

What can cause higher estrogen levels?
There are various factors that can contribute to elevated estrogen (2), including:

• Some antibiotics
• Some herbal remedies
• Phenothiazines (used to treat mental health issues)
• Stress
• Excess body fat
• Some tumors
• Liver disease

What happens if estrogen levels are too high?
The balance between estrogen and testosterone is very important in males. However, as men age, their testosterone naturally decreases. Usually, this doesn’t cause any problems; however, if estrogen levels are abnormally high, this imbalance can cause various symptoms and health risks (2).

The symptoms of high estrogen in males can include:

• Infertility, as high estrogen can slow down sperm production
• Gynecomastia (increased breast tissue)
• Erectile dysfunction
• Ejaculatory dysfunction (premature ejaculation and delayed ejaculation)
• Slowed growth (if high estrogen occurs in children and teens)
• Lower sex drive
• Fatigue
• Hair loss
• Reduced muscle mass
• Increased body fat (more fat tissue can also increase estrogen so this effect is compounded)
• Difficulty concentrating
• Loss of bone density

Can high estrogen cause any serious health complications?
Higher estrogen levels in males are associated with an increased risk of:

• Thyroid problems
• Blood clots
• Heart attack
• Stroke
• Breast cancer
• Prostate cancer

Are there ways to reduce estrogen?
Lifestyle changes may be all that are required to control estrogen levels. Increased physical activity can help reduce body fat, as well as boost testosterone levels to correct an estrogen: testosterone imbalance. Following a diet that is low in fat and high in fiber is also beneficial. Specific foods to include are broccoli and kale, shiitake and portobello mushrooms, red grapes, and green tea (2).

If lifestyle changes are ineffective, there are also medications available to lower estrogen levels back to within the healthy normal range (2).

How can I check my estrogen levels?
We offer two different tests for males to measure estradiol levels. Estradiol is the strongest of the three estrogen hormones. These tests just require a small blood sample collected from a simple finger prick in the privacy of your own home. Test results are available through our online portal, thereby avoiding the need to make any doctor or lab appointments. Of course, you may also wish to discuss your results with your healthcare professional, and this is highly recommended if you receive any results that fall outside the normal range.

The Estradiol (E2) test measures just your estradiol levels, while the Men’s Health Hormone Panel includes estradiol along with five other important biomarkers of male health.

References:
1. Schulster M, et al. (2016) The role of estradiol in male reproductive function. Asian J Androl. 18(3): 435–440.
2. Jewell T (Reviewed by Biggers A) (2019). Risk factors of having high or low estrogen levels in males. Healthline.

Testosterone is that all-important male sex hormone. It is necessary for sex formation, pubertal effects (e.g., body hair and deepening of the voice), sperm development, muscle growth, and the regulation of platelet aggregation (1). So, what happens when a male doesn’t have enough testosterone? Read on to find out about the common signs of low testosterone and what can be done to increase testosterone levels.

Note: Testosterone (at low levels) is also important in females, but this article is focused on male testosterone levels only.

What is defined as low testosterone?
The American Urology Association (LINK) defines low blood testosterone in men as less than 300 ng/dL (~10 nmol/L).

Signs of low testosterone in males
Low testosterone has differing effects depending on the age of the individual. Testosterone deficiency during fetal development can cause the incomplete development of male characteristics, while deficiency at puberty can slow growth and reduce the development of pubic hair, deeper voice, and penis and testes growth (2,3).

Low testosterone in adult males can cause a range of symptoms (2), including:

• Reduced sex drive
• Infertility
• Fatigue
• Reduced lean muscle mass
• Increased body fat
• Irritability
• Erectile dysfunction
• Depression
• Loss of body hair
• Sleeping issues
• Osteoporosis

It is also important to note that these symptoms can be caused by other factors unrelated to testosterone levels, such as opioid use, diabetes, and obesity.

What are the possible causes of low testosterone?
Low testosterone can occur due to conditions that males are born with, such as Klinefelter syndrome, or testosterone may also decline for other reasons, including testicle injury, chemotherapy, infection (e.g., HIV), autoimmune disease, malnutrition, and hormonal imbalances. Metabolic syndrome (which encompasses high blood sugar, unhealthy cholesterol levels, and belly fat), obesity, and using certain medications can also lead to low testosterone production (2).

How is low testosterone diagnosed?
A simple blood test can be taken to measure testosterone levels, such as the test offered here. Additional tests may also be required to determine the cause of the low testosterone, including a luteinizing hormone (LH) blood test and MRI to determine if low testosterone is due to a pituitary problem, as well as an HbA1c test to screen for elevated blood sugar caused by diabetes (2).

What are ways to increase low testosterone?
Often simple lifestyle changes may be all that are required to increase testosterone levels, such as increasing physical activity and improving diet to lose weight for overweight males. In other instances, testosterone therapy may be required. However, testosterone therapy also comes with some potential risks, including an increased risk of blood thickening and interruption of normal sperm production (2).

References:
1. Understanding how testosterone affects men. NIH Research Matters. Sept 2013.
2. What is Low Testosterone? Urology Care Foundation.
3. You and your Hormones, an education resource from the Society of Endocrinology. Reviewed May 2021.

Maybe you’ve heard the term ‘male menopause’ and wondered what it is. Isn’t menopause what women go through and not men?

The answer is yes and no. Menopause literally means “the end of monthly cycles” and is retroactively defined as the final menstrual period followed by 12 months of no menstruation. Menopause in females is usually a natural change, yet may be accompanied by some very unnatural feelings! Think hot flashes, night sweats, and rapid heart rate.

So, what is male menopause?
Male menopause is a commonly used term, but isn’t the most accurate, as it actually refers to a gradual decline in androgen (particularly testosterone) levels, rather than a sudden drop in sex hormones and the end of a monthly cycle like in women. Although that is not to say that men don’t have hormonal cycles. In fact, testosterone levels in men tend to cycle throughout the day (highest in the morning and lowest in the evening), month, and maybe even with the seasons (1).

More accurate terms for the age-related decline of testosterone in males include testosterone deficiency syndrome, androgen deficiency of the aging male, and late-onset hypogonadism (2).

Testosterone declines in all males with age
Male testosterone levels decline as much as 0.4–2% a year from the age of 30 years onwards (3). This gradual decline is mainly due to a reduction in Leydig cell mass in the testicles and/or dysfunction in the normal hormonal control of testosterone production (4). Most men still have testosterone levels within the normal range even as they get older, but there is an estimated 10–25% who have levels that are considered low.

What are the symptoms of low testosterone?
The signs and symptoms of low testosterone are changes that can also occur for a variety of other reasons; hence low testosterone often goes unnoticed. The symptoms can include:

• Reduced libido
• Erectile dysfunction
• Breast discomfort or swelling
• Infertility
• Height loss
• Reduced bone mineral density and muscle mass
• Increased body fat
• Hot flushes or sweats
• Mood changes and/or depression
• Fatigue
• Poor concentration

What can affect testosterone levels in males?
Aside from age, there are various other things that can influence testosterone levels. Obesity is linked to lower testosterone levels, as well as lower physical activity. Other contributing factors may include exposure to environmental toxins and increased temperatures in homes and offices. Each of these factors is thought to also contribute to the gradual overall decline in male testosterone levels, with some reports showing that average levels (across all ages) are declining at a rate of about 1% per year (5).

Can low testosterone be treated?
Treatment recommendations vary for males who have low testosterone that is associated with increasing age. The American College of Physicians recommends testosterone therapy in men with sexual dysfunction, while the Endocrine Society recommends testosterone therapy for men who are showing typical signs and symptoms of low testosterone. However, other experts recommend offering testosterone therapy to men with low testosterone levels even if they are not showing any symptoms.

There are possible risks associated with testosterone therapy including stimulated growth of prostate and breast cancer, and increased risk of heart attack, stroke, or blood clots. Therefore it is important for every individual to consider the pros and cons of testosterone therapy.

Should you get your testosterone levels checked?
Usually, testosterone testing is only recommended for older men who are showing possible signs of symptoms. If low levels are indicated, it is often recommended to repeat the test to confirm the results. Follow-up testing may also be required to determine the cause, such as testing of the pituitary gland.

We offer several different tests that include testosterone:

• Testosterone, Total
• Testosterone, Total and Free (Calculated)
• Testosterone, Total and Free Androgen Index (Calculated)
• Men’s Health Hormone Panel (6 biomarkers)

Each of these tests can be ordered online with at-home sample collection and results available online immediately after testing is complete. No need to make a doctor’s appointment for sample collection. However, if any abnormal results are detected in these tests, we do recommend consulting with your health care professional to discuss additional testing and/or treatment options.

References:
1. Law BM. (2011) Hormones and desire. American Psychological Association. 42(3), 44.
2. Male Menopause. (March 2015) Hormone Health Network.
3. McBride JA, Carson CC, Coward RM. (2016) Testosterone deficiency in the aging male. Therapeutic Advances in Urology. 47-60.
4. Gould DC. (2000) The male menopause: does it exist? West J Med. 173(2): 76-78.
5. Howe N. (2017) You’re not the man your father was. Forbes

About 1 in 8 men will be diagnosed with prostate cancer during their lifetime, so chances are that you know someone who has been affected. And many men can be affected by other prostate problems too. So how do you know if there is an issue with your prostate?

Firstly, what is the prostate?
The prostate is a small gland that helps make semen. It is located just below the bladder and is wrapped around the tube that transports urine and semen out of the body (1). In young men, the prostate is about the size of a walnut, and as men get older, their prostate tends to get larger (2). If it gets too large, it can cause problems. The enlargement of the prostate may be due to cancerous growths or other non-cancer problems (1).

What are the typical symptoms of an enlarged prostate?

• Frequent need to urinate
• Blood in urine or semen
• Painful urination
• Painful ejaculation
• Pain or stiffness in lower back, hips, pelvic or rectal area, or upper thighs
• Dribbling of urine

What are the possible causes of an enlarged prostate?
An enlarged prostate can be caused by prostate cancer or other common non-cancer problems. First, we will discuss the less serious, non-cancer-related issues.

Benign prostatic hyperplasia (BPH) refers to an enlarged prostate, but it is not due to cancerous growths. Medications, surgery, or laser treatment may be required to help treat urinary problems associated with BPH (1).

Acute bacterial prostatitis occurs due to a bacterial infection, with symptoms appearing suddenly and often accompanied by fever or chills. Antibiotics are generally an effective treatment and other medications may also be required to help with pain (1).

Chronic bacterial prostatitis is also caused by a bacterial infection, but in this case, the infection comes back again and again. Sometimes long-term antibiotics are an effective treatment option (1).

Chronic prostatitis is also known as chronic pelvic pain syndrome and is a common prostate issue. Treatment options may include medication, surgery, and lifestyle changes (1).

Each of these issues can cause a lot of pain and discomfort, but the most serious prostate problem is of course prostate cancer. It is common in American men, with higher rates in African Americans, followed by Hispanic and Native Americans. Other risk factors for prostate cancer include being over 50 years, having a family history of prostate cancer, and following a high-fat diet (1).

How is prostate cancer diagnosed?
Routine screening is the best way to detect prostate cancer, as often early prostate cancer (when it is easier to treat) doesn’t cause any symptoms (2).

Screening for prostate cancer may include a prostate specific antigen (PSA) test, such as the one offered here. Elevated PSA can be indicative of prostate cancer, but may also occur due to benign (non-cancerous) conditions. More info about PSA is available here.

Another screening option is a digital rectal examination (DRE) when a health care provider inserts a gloved, lubricated finger into the rectum to feel the prostate. However, this is not recommended as an initial screening method by the US Preventive Services Task Force (3).

If the PSA test and/or DRE are indicating prostate abnormalities, additional diagnostic tests can be conducted, including an ultrasound and a prostate biopsy. The biopsy involves the removal of prostate tissue for examination under a microscope to detect cancer cells (4).

How is prostate cancer treated?
Treatment options for prostate cancer vary depending on the cancer stage and if it has spread elsewhere in the body. If it is determined that the cancer is unlikely to grow quickly and there are no symptoms, no treatment may occur. Instead, the affected person is closely monitored with more frequent PSA tests and prostate biopsies (5).

Other treatment options include surgery to remove the prostate (as well as surrounding tissues if necessary) and radiation therapy to kill the cancer cells. There are also several treatment options currently undergoing investigation, including cryotherapy, chemotherapy, high-intensity focused ultrasound, and hormone therapy (5).

References:
1. Prostate Problems, National Institute on Aging, NIH. Reviewed July 2020.
2. What is Prostate Cancer? American Cancer Society. Revised August 2019.
3. What is screening for prostate cancer? CDC. Reviewed August 2021.
4. How is prostate cancer diagnosed? CDC. Reviewed August 2021.
5. How is prostate cancer treated? CDC. Reviewed August 2021.

What is testosterone?
Testosterone is the primary sex hormone in males, but it is also important in females. Testosterone is mainly secreted from the testes in males, and from the ovaries in females.

What does testosterone do in males?
Although males have much higher levels of testosterone than females, this androgen plays an important role during the life cycle of both genders. In this article, we focus on the role of testosterone in males.

Before birth, testosterone levels are associated with sex formation, with higher levels initiating the development of male reproductive organs. During puberty, testosterone plays a role in many of the typical changes that occur as boys grow into men. This includes increases in body and pubic hair, enlargement of the penis, testes, and prostate gland, deepening of the voice, teenage acne, and remodeling of the facial bones (1,2).

Other roles of testosterone include:

• Increasing libido (sex drive)
• Controlling fat distribution
• Enhancing muscle and bone growth
• Normal sperm production
• Red blood cell production

How are testosterone levels controlled?
Testosterone levels can fluctuate slightly each day, with higher levels in the morning. However, strict control helps to maintain blood testosterone at normal levels. The hypothalamus in the brain releases gonadotrophin-releasing hormone (GnRH), which signals the pituitary gland (also in the brain) to produce luteinizing hormone (LH). LH travels through the blood to the testes to stimulate the synthesis and release of testosterone (1).

As the hypothalamus detects increasing levels of testosterone in the blood, it suppresses the production of GnRH, so in turn, there is less LH released, so less stimulation of testosterone production. This control system is known as negative feedback. As testosterone levels drop, the hypothalamus increases the production of GnRH, therefore more LH is produced, and testosterone synthesis is stimulated once again (1).

What are the symptoms of high testosterone in males?
In male children, elevated testosterone may cause a false growth spurt and early puberty (precocious puberty). This can contribute to infertility issues later in life.

Naturally elevated testosterone in adult males is rare and is not likely to cause any noticeable symptoms. However, males who take anabolic steroids (synthetic substances similar to testosterone) actually end up with lower levels of their naturally produced testosterone (3). Long-term use of anabolic steroids can result in:

• Low sperm counts
• Infertility
• Decreased sex drive
• Smaller testes
• Breast development
• Liver disease
• Acne
• Behavioural changes
• Weight gain
• Damage to heart tissue
• Excessive body hair

What are the symptoms of low testosterone in males?
Low testosterone has differing effects depending on the age of the individual. Testosterone deficiency during fetal development can cause the incomplete development of male characteristics, while deficiency at puberty can slow growth and reduce the development of pubic hair, deeper voice, and penis and testes growth (1,4).

In adult males, testosterone levels naturally decline with age, and this can sometimes be called male menopause (or andropause) (1). However, unnaturally low testosterone can result in:

• Reduced muscle tone and increased body fat
• Loss of body hair
• Weight gain
• Depression
• Reduced sex drive and performance
• Memory loss
• Irritability
• Fatigue
• Sleeping issues.
• Increased risk of osteoporosis

References:
1. You and your Hormones, an education resource from the Society of Endocrinology. Reviewed May 2021.
2. Raggatt LJ, & Partridge NC. (2010). Cellular and molecular mechanisms of bone remodeling. J Biol Chem, 285 (33), 25103-25108.
3. Testosterone – What It Does And Doesn’t Do. (2019). Harvard Health Publishing, Harvard Medical School.
4. What is Low Testosterone? Urology Care Foundation.

Prostate-specific antigen (PSA) is a protein predominantly produced in the prostate by both normal and malignant cells. Blood levels of PSA are a useful indicator of prostatic pathology, to evaluate men at risk of prostate cancer, and for assessment after treatment.

What are the roles of PSA?
In normal healthy individuals, PSA is secreted into the seminal fluid in high concentrations to liquefy seminal gel by proteolytic cleavage of gel-forming proteins. This helps to increase sperm mobility. A small amount of PSA is also normally found in the blood as a result of leakage from the prostate gland (1).

What are normal blood PSA levels?
Healthy males generally have blood total PSA levels less than 4 ng/mL. Although most studies to establish this normal range have been conducted in predominantly white male populations; hence how applicable this value is to other racial or ethnic groups requires further investigation (2).

What do elevated blood PSA levels mean?
High levels of PSA in the blood can be indicative of prostate cancer, but may also occur due to benign (non-cancerous) conditions, including prostatitis (inflammation of the prostate), urinary tract infection, and benign prostatic hyperplasia (BPH, enlargement of the prostate) (3). More info about other causes of high PSA is available here. 

There are three major forms of PSA in the blood, two of which are detectable using current lab techniques – complexed PSA and free PSA (1). The differing levels of these two detectable forms are useful for distinguishing between individuals with BPH and prostate cancer, particularly in men with total PSA levels between 4.1 and 10 ng/mL. Although both abnormalities result in increased total blood PSA, the proportion of free PSA is much higher in individuals with BPH compared to prostate cancer patients (4).

What are the benefits of measuring blood PSA levels?
Prostate cancer is the most frequently diagnosed cancer and second leading cause of cancer deaths in men in the United States (5). Early diagnosis of small tumours that are confined to the prostate provides the best prognosis for recovery from prostate cancer. However, there are often no symptoms in the early stages of prostate cancer. Analyses of blood PSA levels are the most accurate and non-invasive way to detect prostate cancer, particularly in the early stages. These analyses are usually combined with, or followed up by, digital rectal examination (6).

References:
1. McCormack RT, et al. (1995). Molecular Forms of Prostate-Specific Antigen and the Human Kallikrein Gene Family: A New Era. Urology, 45, 729-744.
2. Prostate-Specific Antigen (PSA) Test. National Cancer Institute, NIH. (Updated Feb 2021)
3. Partin AW, Oesterling JE. (1994). The Clinical Usefulness of Prostate Specific Antigen: Update 1994. J Urol, 152, 1358-1368.
4. Ito K, et al. (2003). Free/total PSA ratio is a powerful predictor of future prostate cancer morbidity in men with initial PSA levels of 4.1 to 10.0 ng/mL. Urology. 61(4), 760-4.
5. Parker SL, et al. (1997). Cancer Statistics, 1997. CA Cancer J Clin, 47, 5-27.
6. Crawford ED, et al. (1996). Serum Prostate-Specific Antigen and Digital Rectum Examination for Early Detection of Prostate Cancer in a National Community-Based Program. Urology, 47, 863-869.