Preventing Prostate Cancer: What Can You Do?

For many years, lifestyle changes, pharmaceutical agents and supplements have been studied to find ways to reduce prostate cancer incidence, the second leading cause of cancer death in men in the United States. The potential benefits of a preventive strategy could have a huge impact on the lives of many people. One area of research is hormone-based preventive strategies.

It has been well established that prostate growth, both normal and abnormal, is heavily influenced by hormones, particularly dihydrotestosterone (DHT) and testosterone. Hormone-based prevention strategies for prostate cancer involve the use of medications or interventions that suppress and inhibit the synthesis of these hormones, which fuels the growth of prostate cancer cells. It is hypothesized that suppressing these hormones may hinder the development of prostate cancer. While a few hormone-based approaches have been studied, the current results are still mixed and generally inconclusive.

• 5-alpha reductase inhibitors (5-ARIs)

Among the chemopreventive agents studied, finasteride and dutasteride, both belonging to the class of 5-ARIs, stand out as the most promising and extensively researched. The 5-alpha reductase enzyme plays a crucial role in converting testosterone into DHT, a potent and prevalent androgen in prostate tissue. DHT is instrumental in the embryologic development and growth of the prostate, and promotion of prostate cancer.

Finasteride specifically inhibits 5-AR type 2, while dutasteride inhibits both 5-AR types 1 and 2. Notably, both finasteride and dutasteride were initially designed, approved and have demonstrated their effectiveness in the treatment of benign prostatic hyperplasia (BPH).

While the potential of finasteride and dutasteride as chemopreventive agents seems immense, the results have so far been controversial and complicated. In two primary prevention trials, the Prostate Cancer Prevention Trial (PCPT) and the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, it was shown that while these drugs can reduce the risk of developing low-grade prostate cancer, they may also increase the risk of high-grade cancer. But these initial approximate interpretations were attributed to survival bias.

The most important factor to note is that 5-ARIs cause a decrease in prostate volume, making it easier and more likely to detect high-grade disease that may have gone unnoticed without the use of 5-ARIs. This could have led to the discovery of a higher incidence rate of high-grade prostate cancer. Second, the effectiveness of treating BPH through the use of 5-ARIs may increase the sensitivity of prostate-specific antigen (PSA) levels and digital rectal examination (DRE) in detecting high-grade cancer. However, these hypotheses have not yet been confirmed by meta-analysis of multiple clinical trials. Furthermore, recent long-term results in the PCPT trial show a little benefit in terms of survival in the arm with chemoprevention using finasteride.

• Drugs to combat the effects of metabolic syndrome

The use of the drugs: metformin, statins and aspirin prescribed to mitigate complications of the metabolic syndrome have been associated with a reduced risk of prostate cancer and evaluated for its prevention. Metformin and aspirin are known to reduce the risk of death from different cancers, and are thought to prevent the metabolic syndrome secondary to androgen deprivation therapy.

However, results on prostate prevention remain controversial. Statins and aspirin also reduce PSA values in users compared with non-users introducing confounding factors. Currently, there are insufficient data on the long-term benefits of these drugs in chemoprevention.

Diet

Certain foods have been advocated to decrease the risk of prostate cancer. They have intrinsic biological properties involved in the hormonal regulation of the prostate or more generally play a protective role vis-à-vis carcinogens by antioxidant or anti-tumor properties. Some food compounds even claim nutraceuticals status for prostate cancer prevention. Their real effectiveness is difficult to assess at the individual level.

It is commonly accepted but not proven, that high fat consumption, rich in saturated and polyunsaturated fatty acids such as arachidonic acid increases the risk of advanced prostate cancer, as seen in prospective cohort studies. A large pan-European study of diet (the EPIC study, otherwise known as The European Prospective Investigation into Cancer and Nutrition) demonstrated that those who ate more vegetables did not exhibit a reduced incidence of prostate cancer; while those who ate more meat did not exhibit a greater risk of prostate cancer diagnosis.

Consumption of various elements also suggest a protective effect regarding prostate cancer risk.

• Lycopene and vitamin A (Tomatoes, orange and yellow vegetables)
• Quercetin (Capers, lovage, onions)
• Punicalaginin (Pomegranate)
• Vitamin D (Sunshine, fish liver oil)
• Sulforaphane (Broccoli, cabbage)
• Isoflavonoids (Soybeans, beans)
• Curcumin (Tumeric)
• Epigallocatechin gallate (Green tea)
• Cafestol (Coffee)

Learn more: Can Diet Prevent Prostate Cancer?

Exercise

A healthy lifestyle includes control of body mass index, consumption of fruits and vegetables, limitation of fast sugars and cessation of addictions. Beyond that, taking part in moderate physical activity or sports is a factor that modulates the development of prostate cancers.

The recommended level of regular physical activity is between 3 and 5 times the metabolic equivalent of task (MET) required to sit quietly. You would be mildly out of breath, but still able to maintain a conversation while exercising.

Learn more: Can Exercise Reduce My Prostate Cancer Risk?

It's important to note that the use of these interventions for prostate cancer prevention is a complex and nuanced decision that should be made in consultation with a healthcare provider. Many of these methods are still undergoing research and may not have confirmed benefits. Each approach comes with potential benefits and risks, and the decision should be based on an individual's specific risk factors, overall health, and preferences.