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Living A Normal Life After Prostate Cancer

Dr. Stephen Freedland is a urologist at Cedars-Sinai in Los Angeles, California and the Director of the Center for Integrated Research in Cancer and Lifestyle, Co-director of the Cancer Genetics and Prevention Program and Associate Director for Faculty Development at the Samuel Oschin Comprehensive Cancer Institute.

Dr. Freedland treats the whole patient and not just a man’s prostate cancer.

He frames this month’s conversations about stress, depression, and prostate cancer.

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Historically, the goal was to cure cancer. We don’t really cure other major medical problems like heart disease, diabetes, high blood pressure, or high cholesterol: we manage them. Cancer, in general, and prostate cancer, in particular, are becoming chronic diseases. Occasionally, we need to do something more aggressive, but we really just need a management strategy so that people can live normal, healthy lives even after being diagnosed with cancer.

With this shift from quantity of life to quality of life comes an opportunity for us to have conversations about how prostate cancer and its treatments affect daily life. People are now younger at diagnosis than ever before. They’re still active. They’re still working. They’re still productive members of their families and of society.

How do we help them maintain that while providing the best cancer care? The challenge is how to marry those two. It’s not enough to focus on Gleason score, PSA, and stage. The focus is on the patient. On the person. It’s not just about the numbers.

I applaud Prostatepedia for delving into this subject matter with some very engaging conversations with some of the world leaders on the topic. I work very closely with Dr. Arash Asher at Cedars-Sinai Medical Center. We focus now on nutrition, exercise, and psychosocial health. It’s really spectacular to see. Men are able to maintain much of their quality of life and sometimes feel better than ever.

At the same time, we’re realizing that what works for one patient will not necessarily work for another. There is no shortcut to sitting down with a patient, understanding his needs, goals, and desires, and then working together to come up with a care plan that manages his cancer and his side effects. We want to keep you psychologically strong and able to fight your cancer–but also to live your lives.

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Vitamin D, Omega-3 Fatty Acids, Curcumin + Prostate Cancer

Dr. David Levy is a Clinical Associate Professor in the Department of Urology at the Cleveland Clinic.

Dr. Levy spoke to Prostatepedia about his clinical trial looking at the impact of vitamin D, curcumin, and Omega-3 fatty acids on prostate cancer.

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Can you explain the thinking behind your clinical trial on vitamin D, Omega-3 fatty acids and curcumin in prostate cancer?

Dr. David Levy: Well first let me say there are a number of people involved in this program without whom it would not be where it is today.

I was extremely fortunate. When I finished my residency in Cleveland, I went to MD Anderson Cancer Center in Houston, Texas to do a cancer fellowship.

At that time, we didn’t really understand why cancer occurs and how to treat it. The attitude was: “Cut it out. Radiate it. Give chemo.”

We’re now twenty years down the road and while medical knowledge has advanced tremendously, what are we still doing? Cut it out. Give radiation. Give chemo. People with cancer keep coming and coming. It’s like a conveyor belt. They don’t stop.

About five years ago, I bought an abandoned farm here in Northeast Ohio. The goal was to make it an organic certified produce farm, which I did over three years. In learning about the process to make our farm certified organic, I had to review all the pesticides and chemicals that had been put into the soil and what we had to avoid for over three years to gain the certification. With all these pesticides and chemicals come known side effects.

There is a journal called the Journal of Organic Sciences, which ran a 25-page article on the use of a very common weed killer. Going back to the 1970s, there is a direct correlation of the increased use of this weed killer in commercial agriculture with an increase in liver cancer, colon cancer, kidney cancer, kidney failure, lymphoma, leukemia, thyroid, and prostate cancers. Every cancer went up. They all paralleled the increased use of this common weed killer.

When I read that article, I started to think that there has to be some correlation between environmental exposure and cancers. I started to ask: If you change the environment in which the cells live, do you change their behavior? That has been studied a few times and the results published. Studies have shown the influence of vitamin D on prostate cancer behavior, the impact of Omega-3 and Omega-6 fatty acid ratios on prostate cancer behavior, and the impact of turmeric curcumin on biochemical pathways in the cells. I was thinking about all of that as I came to design the trial.

If you look at populations across the world, prostate cancer rates vary quite dramatically. India, China, and Japan have some of the lowest rates of anywhere in the world. The rate in India is 25 times less than that in the United States, England, France, Germany, Norway, Sweden, or Finland. Why is it that? Men in India all have testicles and testosterone and prostates, but they don’t have prostate cancer. The same goes for Japan and China.

There are pretty interesting differences in terms of the eating habits of these populations and the disease processes that are common in the societies.

It turns out, as far as we can tell, that meat and dairy feed prostate cancer. What do we see in this country on NFL Sunday? What do they serve? They serve hot dogs, French fries, chicken fingers, chicken nuggets, chicken wings, and hamburgers. All of these foods are very high in Omega-6 fats. No one goes to the ballpark to get a bag of broccoli. That doesn’t happen. No one goes there to eat apples.

When we look at our society in terms of the food choices, the foods that are heavily advertised are fast foods, pizzas, and sodas. High sugar loads, high glycemic index foods, and animal fats are all very well correlated with prostate, breast, pancreatic, and colon cancers.

I looked a little further into vitamin D and asked, “Is there a correlation with vitamin D and prostate cell behavior?”

It seems there is. One published study looked at 71,900 men—which is a pretty substantial population—for six and a half years. They found that the lower the vitamin D levels in the blood, the higher the patients’ PSAs, the higher the likelihood of a positive prostate biopsy, and the more aggressive their cancers.

Another vitamin D study published by the SEER committee, which is a national organization that correlates hospital reported statistics throughout the country, looked at 20,000 men. Again, they found low vitamin D, higher PSA, and higher odds of a positive prostate biopsy with significant disease.

Other studies correlate vitamin D levels with prostate cell behavior. It turns out that vitamin D binds on the prostate cell to the androgen receptor. That is where testosterone binds, and testosterone is the main food for prostate cells. Vitamin D binds to this receptor as well. As best we can tell, with low vitamin D levels, the prostate cell machinery churns along like a steel furnace. When the vitamin D levels go up, something happens to the cells’ metabolic rates

Across the country, almost all of the residents of the states north of South Carolina border and from East to West

Coasts are low in vitamin D. I haven’t tested anybody here in Cleveland in almost three years with a normal vitamin D level.

What about turmeric curcumin?

Dr. Levy: Tumeric is used in curry and it contains curcumin. Curcumin is a really good anti-inflammatory. It’s a naturally occurring COX-2 inhibitor. (Celebrex was a COX-2 inhibitor.) It turns out that curcumin has a far greater impact on the biochemistry of cells than just an anti-inflammatory. Curcumin impacts what is called the Hypoxia-inducible factor 1-alpha. This is a factor made in the cells that is involved in their ability to recruit new blood vessels to get more oxygen and more nutrients. Curcumin disrupts that cycle.

Curcumin disrupts the mesenchymalepithelial cell transformation. The mesenchymal-epithelial cell transformation is a process that allows cells to gain the ability to climb outside the prostate and spread to the lymph nodes and bones. Curcumin also impacts the diclofenac acid pathway, which is part of the cell’s Omega-6 metabolic pathway.

There are new publications that show curcumin increases cellular sensitivity to radiation treatment. There are some studies that show it increases the cell’s susceptibility to chemotherapy.

There are over 300 publications in the National Library of Medicine on curcumin and prostate cancer right now. When I started this work about 3. years ago, there were 13 publications on curcumin and prostate cancer. There were so few publications I couldn’t even include them in my suggested regimen to patients. Now, there’s no way we can ignore it.

In my opinion, to not include curcumin would be a disservice to patients because it has such a tremendous impact on cellular behavior without being toxic in any way to the kidneys, the liver, the intestinal system, or the cardiovascular system.

There are very few reported side effects of dosing curcumin. Patients have taken as much a 6 grams per day in capsule form in a study protocol to impact their prostate cancer. We give 2,000 milligrams per day, and in 27 months have not seen any side effects that would curtail our continued use of the supplement.

Are you giving men vitamin D, omega-3 fatty acids, and curcumin all at the same time and then measuring the outcome, or are you separating them out into different groups?

Dr. Levy: No. We’re giving them all together.

After you give patients a combination of the three supplements what kinds of measurements are you doing?

Dr. Levy: We measure the fatty acid ratios in the body. We measure the three individual components of the fish oil:

EPA, DHA, and DPA. We measure the Omega-3/Omega-6 ratios in the blood. We measure linoleic acid levels in the blood. We measure vitamin D levels, and then titrate their doses to get vitamin D levels up to our target range.

There is nothing you can do to measure curcumin except give the dose of the appropriate manufacturer’s preparation.

We spent a lot of time figuring out what was going to get to the cells most efficiently.

And of course, we change the diet.

But the end point of our study is genetics. We do a tissue biopsy at the time of diagnosis. Then the men go on nutrition modification and supplements for a minimum of nine months. After nine months, we repeat the prostate biopsy and do a side-by-side genetic comparison of the prostate tissue from before the diet and supplements regimen with the tissue from after the diet and supplements regimen. Then we see what kinds of changes we have caused by changing the environment in which the cells live.

What kind of patients are you looking for?

Dr. Levy: For the purposes of this genetic study, we are specifically looking at people with low-risk prostate cancer who are on active surveillance or who are candidates for active surveillance.

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Diet + Lifestyle During Treatment

Ms. Greta Macaire is a registered dietician at the University of California, San Francisco.

She spoke with Prostatepedia about the types of recommendations she makes for men with prostate cancer during treatment.

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What do you recommend for men about to start radiation, have surgery, or begin chemotherapy?

Ms. Greta Macaire: I always tell men undergoing radiation, surgery, or chemotherapy that there will be side effects from those treatments. They may need to modify their diet.

For example, patients who get radiation to the prostate bed in the pelvic area (or if lymph nodes are involved) can experience side effects such as gas, bloating, loose stools, and diarrhea. To decrease these side effects, they may have to modify their diet. These are almost always temporary recommendations, though, so it can be really confusing for men.

As a good diet for men with prostate cancer, everyone would recommend a lot of broccoli and vegetables. But men who go into radiation might get gas, bloating, and diarrhea, so they may need to avoid gas-producing vegetables and acidic foods like tomatoes to decrease these side effects. We would also recommend less fiber and more cooked vegetables in that case. But I always let them know these are temporary changes.

Once they recover from radiation, they’ll be able to introduce all these foods back into their diet gradually. It can be a little unnerving for them to think about backing off those foods that they feel are so important. The digestive tract usually heals pretty quickly from something like radiation, so it’s just temporary. Typically, we incorporate those foods back in within a couple of weeks after treatment.

Surgery can also result in gas and bloating because of the pain medications. Constipation and gas can be really uncomfortable because of the surgery. Again, that’s usually temporary.

Any dietary changes before chemotherapy?

Ms. Macaire: The most common side effect I hear about is taste changes: some foods are not appealing or taste like cardboard or metal. Nausea and decreased appetite are other common side effects.

You may have to plan out what you’re going to eat. Eat smaller meals, and eat more often. That way, you’re not getting too much so you’re not going to feel bloated and uncomfortable, but then you’re not going all day without eating, which will make nausea worse. If you experience a metallic taste, we can look at ways to tweak the flavor profile of foods to make them tastier.

Sometimes animal protein brings out the metals in food. There’s more iron and things like that even in chicken or fish. Choose alternative protein sources that don’t have as much of the metallic flavor. Lemon juice can brighten up flavor if everything tastes bland. These small modifications can help with the side effects.

I think it’s comforting for people to hear that these changes are temporary. You’re going to like food again. When you’re done with chemo, things will taste good again. Hold tight.

One of the big side effects of androgen deprivation therapy (ADT) is that men tend to gain weight quickly. What do you recommend for men on hormonal therapy?

Ms. Macaire: We strongly recommend physical activity. The research is pretty consistent on physical activity. Cardiovascular exercise is important, but resistance training is also important. Resistance training maintains lean body mass, which keeps the metabolism higher. The more muscle they can maintain and not lose due to hormone therapy, the more they can keep their body composition on track.

Men on hormone therapy need to be careful about what they eat, especially with foods that can cause weight gain: white foods—which can cause abdominal weight gain—like refined grains and sugary beverages (soda, fruit juice), desserts, and pastries. It’s really important to eat more green leafy vegetables, fill your plate with filling, high-fiber foods. Make at least half your plate non-starchy vegetables, fill a quarter of the plate with lean or plant protein and limit grains or starchy vegetables like potatoes, corn, or peas to no more than the other quarter of the plate.

I wouldn’t recommend a low-carb diet by any means, but eating lots of vegetables and including a lean protein with each meal will help to keep blood sugar levels stable, to prevent spikes and drops.

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Statins, Cholesterol + Prostate Cancer

Dr. Lorelei Mucci specializes in prostate cancer epidemiology and her research focuses on cancer risk and mortality in populations across the globe.

Prostatepedia spoke with her about cholesterol, statins and prostate cancer.

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What is the role of cholesterol in prostate cancer? And statins?

Dr. Mucci: This is a very interesting and important area of research. There have been a number of well conducted epidemiological studies showing that high cholesterol levels are associated with a higher risk of more aggressive prostate cancer.

Cholesterol synthesis and biosynthesis pathways seem to be altered in men with more aggressive forms of prostate cancer. Cholesterol can be used to synthesize androgens; they’re the backbone for androgen synthesis.

The epidemiological evidence for the association between statins and the decreased risk of advanced prostate cancer is quite good. The question is: Is this a true association? Is the mechanism specifically through cholesterol-lowering? There seems to be some evidence that the lowered risk of aggressive prostate cancer may act through regulating cholesterol levels, but some of statins’ effects on aggressive prostate cancer may be independent of cholesterol.

I do think the data are fairly strong around statins. Again, whether that is totally through cholesterol-lowering or other specific pathways is not clear. (See http://ascopubs.org/doi/ pdf/10.1200/JCO.2017.74.7915 to read more of Dr. Mucci’s thoughts on statins and prostate cancer.)

Do statins impact the effectiveness of drugs like Zytiga (abiraterone)?

Dr. Mucci: I am a co-author on a study looking at the effect of statins on androgen deprivation therapy. One of the pathways that statins use to get into prostate cells is the same set of pathways that androgens use.

One thought is that statins may help these other antiandrogen medications by blocking the cellular pathways androgens use. There is both interesting human and experimental data suggesting that statins may benefit these antiandrogen therapies.

This is a very interesting area of research. It might be early on in terms of evidence, but I do think it will be really important to look at how things like statins—and potentially other things like aspirin—are associated with a lower risk of aggressive prostate cancer. It may be really important to think about the possible impact on treatment that other medications that men may be taking at the same time as medications for prostate cancer could have. We may be able to repurpose drugs we hadn’t really thought about before for prostate cancer either on their own or in combination with other therapies.

Should we prescribe statins for all men with prostate cancer? I don’t know that the evidence is good enough for us to recommend that, but we do feel that statins are probably very safe for men who have prostate cancer. If a man with prostate cancer has high cholesterol levels and a high heart disease risk, I think going on a statin is safe. I think it’s premature to suggest that we put all men on statins, though.

Do we have long-term data on statin use from the cardiovascular community?

Dr. Mucci: Looking at secondary outcomes like prostate cancer?

Yes.

Dr. Mucci: That’s a great question. A lot of the cardiovascular studies have been small, but if there’s enough follow-up, and if you pool all the studies together, that may be enough. I would be surprised if someone hasn’t started looking at that.

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Exercise + Metastatic Prostate Cancer?

Professor Rob Newton is the Associate Dean of Medical and Exercise Sciences and the Co-Director of the Exercise Medicine Research Institute, School of Medical and Health Sciences at Edith Cowan University in Perth, Australia.

Prostatepedia spoke to Dr. Newton about his exercise for men with metastatic prostate cancer.

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What exercises do you recommend for men with metastatic prostate cancer?

Dr. Rob Newton: Traditionally, the recommendation for patients with metastatic disease was to rest. The patient should avoid physical activity, and weight/resistance training in particular, due to concerns that bones might fracture at a point of weakness.

We’ve run two studies that challenge this idea. One has been published; the other is ongoing. We’ve been exercising men with metastatic prostate cancer and women with metastatic breast cancer and we’ve seen no adverse events—no increase in pain medication. We’ve seen good physiological responses and improved fitness, strength, and muscle size. It appears that in a well-controlled environment, with appropriately qualified personnel, the risk of a fracture at the site of metastasis is very low.

We use accredited exercise physiologists, but in the United States, men should find a clinical exercise physiologist in a good, monitored facility. Patients respond very well.

It’s counterproductive to recommend to patients with metastatic disease that they rest because they’ll only decline faster and die quicker. Physical inactivity is not an option; they have to exercise. The challenge is to implement this safely and effectively.

Clearly, a home-based program is inadvisable. These patients most likely will have cardiovascular issues, so they’re at risk of having a heart attack or stroke. Their program needs to be monitored by the right personnel using the correct equipment with sound emergency procedures. Our recommendation—and what we have implemented—is a clinic-based program, supervised by exercise physiologists.

In those particular clinical trials, we designed a program so that the exercises avoided the side of the metastasis. For example, if they had a lesion in their left femur, then we wouldn’t exercise that limb to avoid overloading it and causing a fracture.

Some preclinical work in an animal model showed that controlled exercising on the metastatic site compressed tumor progression. When you load bone, bone cells send chemical and electrical signals to other cells that they should respond, generally by laying down more bone to make the bone stronger. Those same electrical and chemical signals also suppress tumor cells.

We have two trials running currently —one in breast cancer and one in prostate cancer—looking at exercise for patients with metastatic spinal lesions. We’re doing controlled isometric contractions to produce compressive load on the side of the lesion. Then we’re using sophisticated MRI techniques to monitor the volume of the metastatic tumors.

Those two studies are ongoing but, again, we’ve had no adverse effects. We have no exacerbation of bone pain. We’re just waiting now for the complete studies to see if, relative to usual care, we’ve observed a slower rate of growth of the bony metastases.

What would you suggest to a man with metastatic disease reading this? Contact his doctor to develop an exercise program?

Dr. Newton: If he has metastatic disease within the skeleton, then he has to avoid any risk of falling. Obviously, contact sports are out, as well as waterskiing, skiing, and snowboarding. It’s critical he exercises. It’s critical he does both aerobic and resistance exercise.

Currently, we recommend he avoid loading the specific site of the metastases, but in the near future, we may see a prescribed exercise program that targets and controls loading. An oncologist or physician would not be able to prescribe an exercise program because they have no background or training in exercise physiology. You have to have the right medical professional give the right exercise prescription.

In Australia, we’re strongly encouraging people to seek the consultation of an accredited exercise physiologist. In the United States, you would look for a clinical exercise physiologist. The American College of Sports Medicine (http://www.acsm.org/) now has specific certifications for exercise oncology, but as this is a relatively new field, there are not many of these health professionals out there at the moment. But the field is growing and specialists can be found.

What if a prostate cancer patient can’t find the right exercise doctor?

Dr. Newton: Visit Movember, which has some support programs in the United States. In Australia, which is as big a country geographically as the United States, we now manage around 2,000 men with prostate cancer entirely via telephone and online.

You mentioned the American Cancer Society’s recommendations for exercise as 75 to 150 minutes a week. Do you think that’s adequate?

Dr. Newton: Absolutely. Seventy-five to 150 minutes per week of moderate to vigorous aerobic exercise and two or more resistance training sessions per week is sufficient to maintain normal health. That means that if you do vigorous exercise, 75 minutes is sufficient. That is for healthy people. If you’ve got cancer, you’re going to have to be more specific about the exercise you do. You’re going to have to do exercise medicine that will give you the best cancer survival.

It’s highly problematic to recommend to patients that they be more physically active. For example, if a patient likes walking and decides to do more walking, that might benefit some aspects of their health. But walking will not benefit a man on ADT who has rapidly developing osteoporosis and sarcopenia (muscle loss). Walking will benefit his cardiorespiratory system, but that probably won’t be what kills him.

Most likely, he’ll become dysfunctional due to low muscle mass and he’ll have an osteoporotic fracture. If it’s in the hip, he probably won’t survive it.

These generic recommendations are helpful generically, but if you have cancer you really need to be assessed by a specialist. That specialist can determine your life-limiting factor and then prescribe medicine tailored to reduce that factor.

Precision exercise medicine?

Dr. Newton: Exactly. We’re working a lot with men with advanced disease, and the American Cancer Society guidelines are difficult for them, particularly if they’ve got cachexia, or muscle wastage. Most likely, 150 minutes per week of moderate intensity exercise is counterproductive. That makes for a greater energy imbalance; they will lose more muscle.

You’ve got to be a little bit careful, particularly with patients who are having a difficult time due to treatment or the stage of their disease. Exercise must be targeted.

That said, any exercise is better than none. The overwhelming clinical evidence and research show that men with prostate cancer—or anyone with any cancer—regardless of the stage of disease, even while undergoing difficult treatments, must be physically active on most, if not, every day of the week. If they adopt a rest strategy, then they will only deteriorate faster. We totally reject the rest strategy; it doesn’t work.

Any amount of physical activity is beneficial and will likely increase survival, but a targeted exercise prescription will be far more effective and safer. We must move to the next stage where highly tailored exercise medicine is standard.

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Exercise Programs For Prostate Cancer

Professor Rob Newton is the Associate Dean of Medical and Exercise Sciences and the Co-Director of the Exercise Medicine Research Institute, School of Medical and Health Sciences at Edith Cowan University in Perth, Australia.

Prostatepedia spoke to Dr. Newton about his exercise recommendations for men with prostate cancer.

Not a member? Join us to read our December issue on diet, lifestyle, and prostate cancer.

What specific exercise plans do you recommend for prostate cancer patients?

Dr. Newton: At the moment, we have a very generic recommendation from the American Cancer Society: complete 75 to 150 minutes per week of moderate to vigorous aerobic exercise and two or more resistance training sessions per week. That’s the same recommendation that the American College of Sports Medicine gives for any healthy adult, whether he or she has cancer or not. That recommendation needs to be more tailored to the stage of prostate cancer and the treatments the patient is undergoing.

I’m writing a letter to the Journal of Clinical Oncology in response to a paper by a group in Perth that they published in the last edition. The paper recommends that the way forward with the management of cancer will be home-based exercise programs prescribed by physicians, and most likely, walking programs. This is a tragic step backward in terms of the management of cancer with exercise medicine. It’s ineffective.

Compliance in home-based programs is woeful. It’s the wrong medicine. Depending on the problem the patient is experiencing, walking may be the wrong medicine. It’s like giving antibiotics as contraception. This is not the direction in which oncology should go.

For men on active surveillance, we have two principal targets. First, we try to reduce the risk of other chronic diseases. At this stage, the prostate cancer is not progressing that fast, so chances are the patients are going to die of something else.

If they’re overweight, obese, or their blood glucose is out of control, for example, metabolic syndrome will kill them long before their prostate cancer will. You’ve got to say, “Why are you worried about your prostate cancer? You won’t live long enough to get it.” If a man is overweight, physically inactive, or has a poor diet, then the focus should be on controlling that, not on the prostate cancer.

The other target for patients on active surveillance is to stimulate the mechanisms that might inhibit the tumor from developing further. We’re starting to get a good understanding of this. The key is to maintain or increase the amount of muscle in the patient’s body.

Muscle produces strong antitumor drugs. It’s natural, internal medicine, but it produces a range of substances that have an antitumor effect. We need to increase the size of the muscle and then activate that muscle regularly to get it to dispense these chemicals.

We’re unsure at the moment of what specific types of exercise drive the greatest quantity and which specific endogenous medicine will suppress tumor growth. At this stage, that’s why we recommend a combination of resistance exercise and aerobic exercise. That should help to slow the tumor progression.

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Diet + Prostate Cancer: What Do We Know?

Dr. Lorelei Mucci specializes in prostate cancer epidemiology and her research focuses on cancer risk and mortality in populations across the globe.

Prostatepedia spoke with her about epidemiology’s take on the link between diet, lifestyle, and prostate cancer.

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LORELEIMucci

What do we know about diet’s impact on prostate cancer?

Dr. Mucci: Epidemiology studies of diet, lifestyle, and prostate cancer have really evolved a lot over time because of PSA screening and our understanding of the disease’s biologic heterogeneity. With PSA screening, we are both diagnosing more men with prostate cancer and diagnosing more men with a more slow-growing form of prostate cancer.

What we’ve learned is that the relationship between the majority of dietary and lifestyle factors seems to be more associated with the risk of aggressive prostate cancer. We’re starting to see that certain factors are associated with either worse or better survival. It has taken us a while as a field to realize that the relationship of risk factors varies for aggressive versus nonaggressive cancer.

It has also taken us a while to understand the role that PSA screening has played in our studies.

The other consideration with prostate cancer is that it could be many years, if not decades, after diagnosis before a man experiences metastatic disease. Thus, we need long-term follow-up studies to understand the impact of lifestyle factors.

In terms of diet, I don’t think there is yet strong evidence for any particular lifestyle factor to say it is causal. There are some probable factors and some new factors we’re starting to think about.

There is good data on the role of an antioxidant known as lycopene. Lycopene is commonly found in high levels in cooked tomato products such as tomato sauce, but also in things like salsa. What is interesting about lycopene is that it accumulates at high levels in the prostate. A number of epidemiology studies have shown lycopene to be associated with a much lower risk of aggressive prostate cancer. There was a small, randomized study in which men were given capsules of cooked tomato products. The study showed lycopene could make changes in the prostate tumor tissue. So there is probable evidence for cooked tomato products and lycopene in prostate cancer prevention.

We are also starting to see evidence emerge around regular consumption of coffee, either decaffeinated or caffeinated. Coffee is one of the strongest antioxidants available, even stronger than berries. Coffee is interesting for a number of cancers. It seems to be associated with a lower risk of liver cancer, potentially colorectal cancer, and diabetes. In randomized studies, we also see that coffee helps regulate insulin levels after a meal. Insulin may be very important for advanced prostate cancer.

Again, I wouldn’t say this evidence is convincing yet, but we’re starting to see many studies suggesting the benefit of regular coffee consumption.

There is also emerging evidence about fish consumption. In particular, fatty fish like tuna or salmon are associated with a lower risk of aggressive prostate cancer.

On the other side, there is now data suggesting high calcium intake at the levels you’d get more from many supplements may be associated with an increased risk of a more aggressive form of prostate cancer.

Finally, the association between obesity and aggressive prostate cancer is strong. Any dietary factors, or dietary patterns, that contribute to obesity may be associated with more aggressive prostate cancer and with worse outcomes for patients.

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