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The results of a recent study in the United Kingdom are in line with what a number of researchers (here, here, and here) have been writing about for a while - that studies show that some cancer screening (e.g. for prostate cancer) of people with no symptoms does not save lives.

The UK study randomly assigned men (aged 50 to 69) to get a PSA test one time or to not get a PSA test (the controls). The PSA test measures prostate-specific antigen in the blood, and is typically used to screen for prostate cancer. It is not done routinely in the UK. They found that while more men were diagnosed with prostate cancer in the PSA group, after 10 years there was no statistical difference in death rates between the two groups. As the researchers themselves said, the PSA screening test resulted in "an increase in the detection of low-risk prostate cancer cases" (the ones that wouldn't cause a problem). But not in the aggressive killer cancers.  However, the researchers are now continuing the study to see if there are differences in the 2 groups after an even longer period of time. From Medical Xpress:

One-off PSA screening for prostate cancer does not save lives

Inviting men with no symptoms to a one-off PSA test for prostate cancer does not save lives according to results from the largest ever prostate cancer trial conducted over 10 years by Cancer Research UK-funded scientists and published today (Tuesday) in the Journal of the American Medical Association (JAMA). Researchers at the Universities of Bristol and Oxford found that testing asymptomatic men with PSA detects some disease that would be unlikely to cause any harm but also misses some aggressive and lethal prostate cancers.

The CAP Trial, which spanned almost 600 GP practices in the UK and included more than 400,000 men aged 50-69, is the largest trial ever to investigate prostate cancer screening. The trial compared 189,386 men who were invited to have a one-off PSA test with 219,439 men who were not invited for screening. After an average of 10 years follow up, there were 8,054 (4.3%) prostate cancers in the screened group and 7,853 (3.6%) cases in the control group. Crucially, both groups had the same percentage of men dying from prostate cancer (0.29%).

While some prostate cancers are aggressive and lethal, others are clinically insignificant and will never lead to any harm or death if left undetected. Ideally, aggressive prostate cancers need to be identified and treated as early as possible. But finding a cancer that would never have caused men harm during their lifetime can have a serious impact on quality of life, including the worry of a cancer diagnosis, the possibility of infection following a biopsy and impotence and incontinence following treatment. ... Dr Richard Roope, Cancer Research UK's GP expert, said: "The PSA test is a blunt tool missing the subtleties of the disease and causing men harm.

Prostate cancer is something that men worry about, especially because it is the most common cancer in men, and because it can take several forms. On one hand, a tumor can be "indolent" or so slow growing that it just needs to be monitored, or sometimes it can be very aggressive and even lead to death. That's why the possibility of a dietary pattern (what a person eats) having an effect on the cancer's progression or aggressiveness is very exciting - if true, it would be something people could do to improve their prostate cancer outcome. Or perhaps even prevent it in the first place. Studies up to this point have been mixed, with no clear results.

A recent large study conducted in Spain found that those men with prostate cancer who had a high adherence to a Mediterranean diet had a lower risk of aggressive prostate cancer, as compared to those following a typical Western diet (large amounts of fatty dairy products, refined grains, processed meat, caloric beverages, sweets, fast food, and sauces) or a Prudent diet (low-fat dairy products, whole grains, fruits, vegetables, and juices). A Mediterranean dietary pattern is rich in fruits and vegetables, and also fish, legumes, boiled potatoes, olives and olive oil, vegetable oils, and a low intake of juices.

The researchers also discussed that there are many similarities with breast cancer and prostate cancer, including risk factors. They found in an earlier study in Spain that eating a Western diet is associated with breast cancer risk, the Prudent diet is not associated with breast cancer, and the Mediterranean diet seems to be protective for breast cancer. From Medical Xpress:

A more complete Mediterranean diet may protect against aggressive prostate cancer

In a new study published in The Journal of Urology, researchers determined that men who followed a Mediterranean diet, rich in fish, boiled potatoes, whole fruits, vegetables, legumes, and olive oil, and low consumption of juices had lower risk of aggressive prostate cancer (PC) than those who followed other dietary patterns like Prudent or Western diets. ..."Our results show that a diet oriented towards the prevention of aggressive tumors in the prostate should probably include important elements of the Mediterranean diet such as fish, legumes, and olive oil, and suggest that a high intake of fruits, vegetables, and whole grains might not be enough."

The authors explored the relationship between the risk of having PC and dietary patterns as part of the MCC-Spain study, a Spanish case-control study that involved 733 patients with histologically confirmed PC and 1,229 healthy men with a mean age of 66 years from seven Spanish regions. Anthropometric, epidemiologic, and dietary data were collected.

Adherence to the three dietary patterns of Western, Prudent, and Mediterranean, which characterize the dietary habits of the Spanish population, was evaluated, The Western [dietary] pattern includes consumption of large amounts of fatty dairy products, refined grains, processed meat, caloric beverages, sweets, fast food, and sauces. The Prudent pattern involves consumption of low-fat dairy products, whole grains, fruits, vegetables, and juices. Finally, the Mediterranean pattern consists of high consumption of fish, boiled potatoes, fruits, vegetables, legumes, and olive oil, and low consumption of juices. The diets were graded according to the degree of adherence to each pattern and assigned to four quartiles from lower to higher adherence within each pattern.

Only a high adherence to Mediterranean dietary pattern appeared to be associated with a lower risk of aggressive PC. Prudent and Mediterranean dietary patterns showed different effects in low and high grade tumors. 

PC was assessed using Gleason scores of tumor aggressiveness (<6 or ?6) and clinical stage (cT1b to cT4). A Gleason score of <6 typically indicates a less aggressive tumor with generally good prognosis. Lower clinical stage (cT1-cT2a) indicates a tumor that has not spread. Results indicated that for more aggressive and more extensive tumors (Gleason >6 and stages cT2b to cT4), only high adherence to the Mediterranean diet showed a statistically significant protective effect. All other dietary patterns and tumor characteristics showed little or no correlation and did not achieve statistical significance. [Original study.]

 Another reason exercise is good for you: A large study found that men who exercise after a diagnosis of prostate cancer (but which is not metastatic) had a lower risk of dying from prostate cancer - as compared to those men who don't exercise.

So get out there and do something that gets you moving - and yes, walking is an exercise (Note: 1 mile = 20 minutes of walking, thus 3 miles = 1 hour). In this study the average age at diagnosis was 71, but studies find that exercise has numerous benefits at all ages. Some doctors even think of exercise as "anticancer therapy" (here, here). Also, exercise has anti-inflammatory benefits, and current thinking is that chronic inflammation is linked to cancer.

The American Cancer Society in its cancer prevention guidelines recommends that adults should be physically active, and get at least 150 minutes of moderate physical activity or 75 minutes of vigorous intensity activity each week (or a combination of these), preferably spread throughout the week.

From Medscape: Exercise Linked to Lower Mortality With Early Prostate Cancer

Men with nonmetastatic prostate cancer may have longer survival the more they exercise, a recent study suggests. For these men, regular moderate or vigorous physical activity was associated with 31 percent to 37 percent lower likelihood of death during the study, compared to more modest amounts of exercise. “This confirms and expands on previous work that shows an inverse association between recreational physical activity after diagnosis and risk of prostate cancer-specific mortality,” said lead study author Ying Wang of the American Cancer Society in Atlanta, Georgia, in email to Reuters Health.

Wang and colleagues pulled data from a large, long-term study group established by the American Cancer Society in 1992, focusing on 7,000 men who were diagnosed with prostate cancer between 1992 and 2011. The average age at cancer diagnosis was 71, and there were 2,700 deaths through 2012, including 450 due to prostate cancer and 750 due to heart disease. The average time from diagnosis to death was about eight years for those who died from cancer and 10 years for those who died from other causes.

Men who were more active before diagnosis were more likely to have lower-risk cancer tumors and a history of prostate screenings. They were also leaner, more likely to be nonsmokers and vitamin users and they ate more fish. Both before and after diagnosis, walking accounted for 73 percent of the physical activity that men did, followed by 10 percent for cycling and 5 percent for aerobic exercise, according to the report online now in European Urology.

Based on exercise levels before diagnosis, moderate to vigorous exercise, including walking, was linked to lower risk of death from prostate cancer, but only for men with lower-risk tumors. But after the diagnosis, the same levels of exercise were linked to lower risk of death from prostate cancer for all men, although the apparent benefit of walking was no longer statistically meaningful. [Original study.]

This is a thought-provoking study that looked at environmental quality and cancer incidence in counties throughout the US. The researchers found that the more polluted the county, the higher the cancer incidence. An increase in cancer rates was associated with poorer air quality and the "built environment" (such as major highways). They correctly point out that many things together can contribute to cancer occurring - and this is why looking at how polluted the air, water, etc. together is important.

They looked at the most common causes of cancer death in both men (lung, prostate, and colorectal cancer), and women (lung, breast, and colorectal cancer). They found that prostate and breast cancer demonstrated the strongest associations with poor environmental quality. [Original study.]

The researchers point out that about half of cancers are thought to have a genetic component, but therefore the other half have environmental causes. Other studies already find that environmental exposures (e.g., pesticides, diesel exhaust) are linked to various cancers. But this study was an attempt to look at interactions of various things in the environment with rates of cancer - because we all are exposed to a number of things simultaneously wherever we live, not just to exposures to one thing. Thus this study looked at associations in rates of cancer. 

Of course there is also a lifestyle contribution to many cancers that wasn't looked at here (nutrition, alcohol use, exercise). They also pointed out that many counties in the US are large and encompass both very polluted and non-polluted areas - and that those counties should be broken up into smaller geographic areas when studied. [More air pollution studies.] From Science Daily:

Poor overall environmental quality linked to elevated cancer rates

Nationwide, counties with the poorest quality across five domains -- air, water, land, the built environment and sociodemographic -- had the highest incidence of cancer, according to a new study published in the journal Cancer. Poor air quality and factors of the built environment -- such as the presence of major highways and the availability of public transit and housing -- -- were the most strongly associated with high cancer rates, while water quality and land pollution had no measurable effect.

Previous research has shown that genetics can be blamed for only about half of all cancers, suggesting that exposure to environmental toxins or socioeconomic factors may also play a role. "Most research has focused on single environmental factors like air pollution or toxins in water," said Jyotsna Jagai, research assistant professor of environmental and occupational health in the University of Illinois at Chicago School of Public Health and lead author of the study. "But these single factors don't paint a comprehensive picture of what a person is exposed to in their environment -- and may not be as helpful in predicting cancer risk, which is impacted by multiple factors including the air you breathe, the water you drink, the neighborhood you live in, and your exposure to myriad toxins, chemicals and pollutants."

To investigate the effects of overall environmental quality, the researchers looked at hundreds of variables, including air and water pollution, pesticide and radon levels, neighborhood safety, access to health services and healthy food, presence of heavily-trafficked highways and roads, and sociodemographic factors, such as poverty. Jagai and her colleagues used the U.S. EPA's Environmental Quality Index, a county-level measure incorporating more than 200 of these environmental variables and obtained cancer incidence rates from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program State Cancer Profiles. Cancer data were available for 85 percent of the 3,142 U.S. counties.

The average age-adjusted rate for all types of cancer was 451 cases per 100,000 people. Counties with poor environmental quality had higher incidence of cancer -- on average, 39 more cases per 100,000 people -- than counties with high environmental quality. Increased rates were seen for both males and females, and prostate and breast cancer demonstrated the strongest association with poor environmental quality.

The researchers found that high levels of air pollution, poor quality in the built environment and high levels of sociodemographic risk factors were most strongly associated with increased cancer rates in men and women. The strongest associations were seen in urban areas, especially for the air and built environment domains. Breast and prostate cancer were most strongly associated with poor air quality.

Surprising results (to me at least) from research comparing various diets and incidence of several cancers in 11,082 individuals in the Netherlands over a 20 year period. I expected the daily meat eaters to have higher rates of the 3 cancers studied, but no....

Their main conclusion: vegetarians, pescetarians (no meat, but does eat fish), and low-meat consumers did not have a reduced risk of lung, postmenopausal breast, and overall prostate cancer when compared with individuals consuming meat on a daily basis. This is after taking confounders such as smoking into account (because smokers have higher rates of cancers such as lung cancer). The researchers do point out that some other similar studies had mixed results, but that perhaps those studies did not take confounders (variables that distort the results) such as smoking, physical activity levels, alcohol consumption, etc. into account. From the European Journal of Clinical Nutrition:

Vegetarianism, low meat consumption and the risk of lung, postmenopausal breast and prostate cancer in a population-based cohort study

The few prospective studies that examined lung, female breast and prostate cancer risk in vegetarians have yielded mixed results, whereas none have studied the effects of low meat diets. Moreover, little is known about the explanatory role of (non-) dietary factors associated with these diets.The Netherlands Cohort Study—Meat Investigation Cohort (NLCS-MIC)— is an analytical cohort of 11,082 individuals including 1133 self-reported vegetarians (aged 55–69 years at baseline). At baseline (1986), subjects completed a questionnaire on dietary habits and other risk factors for cancer and were classified into vegetarians (n=691), pescetarians (n=389), 1 day per week (n=1388), 2–5 days per week (n=2965) and 6–7 days per week meat consumers (n=5649).

After 20.3 years of follow-up, 279 lung, 312 postmenopausal breast and 399 prostate cancer cases (including 136 advanced) were available for analyses. After adjustment for confounding variables, we found no statistically significant association between meat consumption groups and the risk of lung cancer. As well, no significant associations were observed for postmenopausal breast and overall prostate cancer. After adjustment for confounders, individuals consuming meat 1 day per week were at a 75% increased risk of advanced prostate cancer compared with 6–7 days per week meat consumers.

Vegetarians, pescetarians and 1 day per week meat consumers did not have a reduced risk of lung, postmenopausal breast and overall prostate cancer compared with individuals consuming meat on a daily basis after taking confounders into account.

Although vegetarian diets are primarily defined by the absence of meat and fish, they are also shown to be associated with high intakes of fruits and vegetables and a favorable distribution of non-dietary factors.1, 2 Consequently, vegetarian diets may reduce the risk of different types of cancers through multiple mechanisms, depending on the etiology and preventability of the tumor.3, 4

We previously reported a nonsignificantly reduced risk of vegetarian and low meat diets on colorectal, and especially rectal, cancer5 and set out to study its effect on three other major cancers. Although meat consumption has been hypothesized to be implicated in the etiology of lung, female breast and prostate cancer, data are not consistent across studies and meat subtypes.6, 7, 8However, on the basis of the existing body of literature, vegetarians may be at a lower risk of developing lung cancer (because of lower smoking rates) and to postmenopausal breast cancer (because of lower alcohol consumption, lower body mass index and higher physical activity levels).

Results from this prospective cohort study showed that, in age- and sex-adjusted models, vegetarians and pescetarians were at a reduced risk of lung cancer compared with individuals consuming meat on a daily basis. This effect disappeared after taking confounders, especially smoking, into account. We did not observe an association between the meat consumption group and the risk of post-menopausal breast and overall prostate cancer.

Our null findings regarding post-menopausal breast cancer risk are in line with other prospective studies comparing vegetarians with non-vegetarians and a pooled analysis of five cohort studies on breast cancer mortality. In contrast, the UK Women’s Cohort Study reported a lower post-menopausal breast cancer risk among non-meat consumers compared with high meat consumers,14 although this was not observed in their dietary pattern analyses.15 Vegetarian diets are rich in fiber and soy. Fiber was associated with a reduced risk of breast cancer in a meta-analysis of prospective studies,19 and soy contains isoflavones, which have previously been associated with a significant reduced risk of postmenopausal breast cancer in Asian populations.20 However, compared with the average soy intake in four Asian countries (ranging from 38 to 134 g/day21), the soy product intake among vegetarians in our population was likely too low to exert an effect (~15g per day).

We've all heard of immunotherapy as a possible future treatment for many cancers, but other possible treatments are also being tested. Two possibilities caught my eye. The first study is looking at exercise for advanced prostate cancer - to extend life, and the other is testing a vaccine for those with prostate cancer who haven't yet treated it (they've just been doing "active surveillance" instead).  And since the studies are occurring now, and people are still joining, then the results are still unknown and won't be known for years. But one can hope.... Exercise as anticancer therapy? A vaccine after cancer diagnosis?

From Medical Xpress: Exercise, future anticancer therapy?

At age 70, Alfred Roberts plays hockey twice a week. Nothing special, right? Except that for three years he has had advanced prostate cancer, which has spread to his bones. "I've always been active. Hockey keeps me in shape and keeps my mind off things. I've got friends that have played until age 80, and my goal is to beat them!" said the veteran stick handler.

Several studies have demonstrated the benefits of exercise to improve the quality of life of people with cancer. But Dr. Fred Saad, urologist-oncologist and researcher at the University of Montreal Hospital Research Centre (CRCHUM), goes further. He believes that physical exercise has a direct effect on cancer, as effective as drugs, for treating patients with prostate cancer, even in advanced stages of the disease.

"Typical patients with metastases often become sedentary. It is thought that this affects cancer progression," he said. Together with Robert Newton, professor at the Edith Cowan University Exercise Medicine Research Institute in Australia, Dr. Saad is leading the first international study which aims to demonstrate that exercise literally extends the life of patients with metastatic prostate cancer....In the coming weeks, some sixty hospitals across the world will begin recruiting patients. In total, nearly 900 men with advanced prostate cancer will participate.

"We will study exercise as if it were a drug added to standard treatments. All patients will be treated within the latest scientific knowledge for this type of cancer. They will continue to follow their therapies and take their medications. But half of the patients will receive psychosocial support with general recommendations on physical exercise. The other half will also follow a high intensity exercise program," he explained.

The exercise medicine expert Professor Robert Newton has designed a specific strength and cardiovascular training program for patients in the "exercise" group. "They will have an hour of aerobic and resistance training three times a week. An exercise specialist will supervise them for the first 12 months, and then they will continue without direct supervision. We will evaluate quality of life, appetite, and treatment tolerance in relation to their improved physical condition," said Professor Newton, who is co-director of the Edith Cowan University, Exercise Medicine Research Institute.

The hypothesis is that exercise has a direct impact on cancer progression in addition to helping patients better tolerate therapy. Ultimately, they will live longer. The results of this large study, which involves some one hundred researchers in Canada, the US, Australia, Ireland, the Netherlands, and the UK, will not be known for five years. Could the findings be extended to other types of cancer? It is too early to tell, but researchers are betting that exercise could well become the next anticancer therapy. Alfred Roberts is also convinced that exercise helps defy the odds: "As long as I can skate, I'll play hockey!"

From Medscape:  A Treatment Vaccine for Low-Risk Prostate Cancer

A Louisiana-based biopharmaceutical company is betting that its experimental immunotherapeutic vaccine can keep previously untreated prostate cancer in check. The company, OncBioMune Pharnaceuticals, Inc, in Baton Rouge, is planning to test the vaccine, dubbed ProscaVax, in a phase 2 trial for patients with previously untreated prostate cancer and in a second trial for patients with recurrent or hormone-refractory disease. The trial of a treatment vaccine in untreated, low-risk prostate cancer patients is novel.

 Two recent studies link low vitamin D levels with more aggressive cancers: aggressive prostate cancer in men and more aggressive breast cancers (in mice and women). Researchers generally advise people to take 1000 to 2000 international units per day of vitamin D3 to maintain normal blood levels of of more than 30 nanograms/milliliter. The best source of vitamin D is sunlight, which is why vitamin D is frequently called the sunshine vitamin.

From Science Daily:  Low vitamin D predicts aggressive prostate cancer

A new study provides a major link between low levels of vitamin D and aggressive prostate cancer. Northwestern Medicine research showed deficient vitamin D blood levels in men can predict aggressive prostate cancer identified at the time of surgery.

"Vitamin D deficiency may predict aggressive prostate cancer as a biomarker," said lead investigator Dr. Adam Murphy, an assistant professor of urology at Northwestern University Feinberg School of Medicine and a Northwestern Medicine urologist. "Men with dark skin, low vitamin D intake or low sun exposure should be tested for vitamin D deficiency when they are diagnosed with an elevated PSA or prostate cancer. Then a deficiency should be corrected with supplements."

Aggressive prostate cancer is defined by whether the cancer has migrated outside of the prostate and by a high Gleason score. A low Gleason score means the cancer tissue is similar to normal prostate tissue and less likely to spread; a high one means the cancer tissue is very different from normal and more likely to spread. The study was part of a larger ongoing study of 1,760 men in the Chicago area examining vitamin D and prostate cancer. The current study included 190 men, average age of 64, who underwent a radical prostatectomy to remove their prostate from 2009 to 2014.

Of that group, 87 men had aggressive prostate cancer. Those with aggressive cancer had a median level of 22.7 nanograms per milliliter of vitamin D, significantly below the normal level of more than 30 nanograms/milliliter. The average D level in Chicago during the winter is about 25 nanograms/milliliter, Murphy noted....The Institute of Medicine recommends 600 international units of D per day, but Murphy recommends Chicago residents get 1,000 to 2,000 international units per day.

From Medical Xpress:  Vitamin D deficiency contributes to spread of breast cancer in mice, study finds

Breast tumors in laboratory mice deficient in vitamin D grow faster and are more likely to metastasize than tumors in mice with adequate levels of vitamin D, according to a preliminary study by researchers at the Stanford University School of Medicine.The research highlights a direct link between circulating vitamin D levels and the expression of a gene called ID1, known to be associated with tumor growth and breast cancer metastasis.

The finding builds upon several previous studies suggesting that low levels of vitamin D not only increase a person's risk of developing breast cancer, but are also correlated with more-aggressive tumors and worse prognoses. Although the research was conducted primarily in mice and on mouse cells, the researchers found in a study of 34 breast cancer patients that levels of circulating vitamin D were inversely correlated with the expression levels of ID1 protein in their tumors, and they confirmed that a vitamin D metabolite directly controls the expression of the ID1 gene in a human breast cancer cell line.

Once ingested or made by the body, vitamin D is converted through a series of steps into its active form, calcitriol. Calcitriol binds to a protein in cells called the vitamin D receptor, which then enters the cell's nucleus to control the expression of a variety of genes, including those involved in calcium absorption and bone health.

In the new study, Williams and Aggarwal investigated whether vitamin D levels affected the metastatic ability of mouse breast cancer cells implanted into the mammary fat pad of laboratory mice. One group of 10 mice was first fed a diet lacking in the vitamin for 10 weeks; the other 10 received a normal dose in their food. Mice fed a diet deficient in vitamin D developed palpable tumors an average of seven days sooner than their peers, and after six weeks of growth those tumors were significantly larger in size than those in animals with adequate vitamin D levels.

Reading this recent study, I was struck by how the results are evidence for eating sulforaphane containing foods, such as kale, cauliflower, brussels sprouts, broccoli, and cabbage for health and preventing cancer (due to anti-tumor activity). It is debatable whether it is support for taking supplements (here a sulforaphane supplement called BSE), even though the researchers were testing the supplement. Seven days of taking a supplement without "serious adverse events" (but they did have minor ones such as "mild abdominal discomfort") is too short a length of time for any support for a product. The real test would be seeing what health effects, both positive and negative, are after a year or two of taking the supplement.

Numerous other studies have found that eating foods are linked to good health, while taking supplements are linked to various health problems. Some scientists speculate that it's because the doses in supplements are too high - that they're much higher than what is found in foods. Also, supplements may be missing important nutrients that are found in foods. Bottom line: eat real foods for health and and cancer prevention, including several servings a week of cruciferous vegetables (cauliflower, cabbage, garden cress,bok choy, broccoli, brussels sprouts and similar green leaf vegetables). From Futurity:

Can A Broccoli Sprout Pill Fight Cancer?

A compound in broccoli sprouts may not only help prevent cancer but also treat itSulforaphane is found in vegetables such as kale, cauliflower, and cabbage—and in particularly high concentrations in young broccoli sprouts. Sulforaphane also is available as a dietary supplement called BSE.

Researchers at the Texas A&M Health Science Center Institute of Biosciences and Technology, along with collaborators in Oregon, had previously found that sulforaphane could inhibit colon and prostate cancer cells in the laboratory. They’ve now shown that it seems to help humans as well. A paper published in the journal Clinical Epigenetics hints at the biological pathways involved and suggests BSE is generally safe.

“We have not seen any serious adverse events in healthy volunteers who consumed BSE pills for seven days,” says Praveen Rajendran, an assistant professor at Texas A&M University, although some people did experience mild abdominal discomfort.

In a separate clinical study, 28 human volunteers over the age of 50, who were undergoing routine colonoscopies, were surveyed for their cruciferous vegetable-eating habits. When their colon biopsies were examined, those who ate more servings were found to have higher levels of expression of the tumor suppressor gene p16 than those who ate few or no cruciferous vegetables.

This effect on p16 held even for people who didn’t eat these vegetables every single day, which may seem strange, as a single serving of sulforaphane is generally cleared from the body in less than 24 hours. “This hints at the possibility that epigenetic mechanisms are initially triggered by sulforaphane and its metabolites, and downstream mechanisms could be sustained, at least in the short-term, even after compounds are eliminated from the body.” In other words, eating vegetables containing sulforaphane may change your genes and help your body fight tumor growth.

However, it’s not all good news. In animal models, sulforaphane was shown to generally inhibit the development of colon cancer, but it’s a bit of a two-edged sword. Sulforaphane induces a protein called Nrf2, which has beneficial antioxidant and detoxifying effects—and is obviously good for fighting cancer. Later in the development of cancer, though, Nrf2 can also have a role in tumor growth and can even enhance the buildup of plaque in the arteries.

Data from 2 huge studies was analyzed and found that vigorous exercise and other healthy habits seems to cut the chance of developing aggressive and lethal prostate cancer up to 68 percent in men over 60. The beneficial lifestyle habits are: weekly vigorous exercise or activity to the point of sweating, at least 7 servings of tomatoes a week, at least one serving of fatty fish per week, reduced intake of processed meat, and being a long-term non-smoker. Interestingly, vigorous activity or exercise to sweating - ideally up to 3 hours a week - showed the biggest association with a 34 % reduced risk of aggressive prostate cancer.From Science Daily:

Working up a sweat may protect men from lethal prostate cancer

A study that tracked tens of thousands of midlife and older men for more than 20 years has found that vigorous exercise and other healthy lifestyle habits may cut their chances of developing a lethal type of prostate cancer by up to 68 percent.

While most prostate cancers are "clinically indolent," meaning they do not metastasize and are nonlife-threatening, a minority of patients are diagnosed with aggressive disease that invades the bone and other organs, and is ultimately fatal. Lead author Stacey Kenfield, ScD, of UCSF, and a team of researchers at UCSF and Harvard, focused on this variant of prostate cancer to determine if exercise, diet and smoke-free status might have life-saving benefits.

In the study, published in the Journal of the National Cancer Institute, the researchers analyzed data from two U.S. studies: the Health Professionals Follow-Up Study that tracked more than 42,000 males ages 40 to 75, from 1986 to 2010; and a second, the Physicians' Health Study that followed more than 20,000 males ages 40 to 84, from 1982 to 2010.

To gage the effects of lifestyle habits, the researchers developed a score based on the results of the health professionals survey, then applied it to the physicians' study. They assigned one point for each affirmative response to questions about regular intense exercise that induced sweating, body mass index (BMI) under 30, tobacco-free status for a minimum of 10 years, high intake of fatty fish, high intake of tomatoes and low intake of processed meat.

The researchers identified 576 cases of lethal prostate cancer in the health professionals' group and 337 cases in the physicians' group. Participants with 5 to 6 points in the health professionals' group had a 68 percent decreased risk of lethal prostate cancer and a 38 percent decreased risk was observed in the physicians' group for the same comparison.

"We estimated that 47 percent of lethal prostate cancer cases would be prevented in the United States if men over 60 had five or more of these healthy habits," said Kenfield, assistant professor in the Department of Urology at UCSF Medical Center, and formerly of the Department of Medicine at Harvard Medical School in Boston, where the study was initiated.

"It's interesting that vigorous activity had the highest potential impact on prevention of lethal prostate cancer. We calculated the population-attributable risk for American men over 60 and estimated that 34 percent of lethal prostate cancer would be reduced if all men exercised to the point of sweating for at least three hours a week," Kenfield said.

The researchers also calculated that lethal prostate cancer among American men over 60 would be cut by 15 percent if they consumed at least seven servings of tomatoes per week and that 17 percent would be spared this diagnosis if they consumed at least one serving of fatty fish per week. Reducing intake of processed meats would cut the risk by 12 percent, they reported. In contrast, the population-attributed risk for smoking was 3 percent, largely because the majority of older American men are long-term nonsmokers.

A report by 3 prominent specialists (including Gilbert Welch - who has been discussed in earlier posts) about trends in metastatic breast and prostate cancer came out today in the New England Journal of Medicine. The biggest finding was that mammograms have not cut the rate of metastatic breast cancer. Mammography screening is based on the hope that cancer that is detected in an early, localized phase can then be treated more easily and that it would reduce the numbers of metastastic cancers (that spread to lymph nodes and to more distant organs) that eventually kill. However, this has not happened.The incidence of metastatic breast cancer has been stable since 1975, and the average age of diagnosis among women older than 40 is still 63.7 years . The authors theorize that "breast cancer is a systemic disease by the time it's detectable". From Medical Xpress:

Study: Mammograms haven't cut rate of advanced breast cancer

A new report raises fresh questions about the value of mammograms. The rate of cancers that have already spread far beyond the breast when they are discovered has stayed stable for decades, suggesting that screening and early detection are not preventing the most dangerous forms of the disease. The report, in Thursday's New England Journal of Medicine, is by three prominent cancer specialists and is based on federal statistics going back to the 1970s.

"We're undergoing what I think for the public is a very confusing debate" about screening, but it's really "a course correction" prompted by more awareness of its risks and benefits to various groups of women, said Dr. H. Gilbert Welch, a health policy expert at Dartmouth Medical School. "All they heard for years was, 'there are only benefits.'" He is the lead author of the report, co-written with Dr. David Gorski of Wayne State University School of Medicine in Detroit and Dr. Peter Albertsen of the University of Connecticut Health Center in Farmington.

"Screening offers hope that cancer can be detected in an early, localized phase when it's more amenable to treatment," they write, but that assumes that cancer starts in one place, grows and then spreads. If that was always true, screening would reduce the rate of advanced cancers. And that has not happened. The rate of breast cancers detected at an advanced stage has been stable since 1975, despite wide use of mammography since the 1980s. The average age of women diagnosed with cancer also has remained around 63, another sign cancers are not being found sooner.

The trends suggest that some breast cancers are already "systemic" or widely spread from the start, and that finding them sooner has limited impact. "Screening mammography has been unable to identify those bad cancers, destined to become metastatic, at an earlier stage. That doesn't say mammography doesn't help less aggressive cancers," but those are less likely to prove deadly, Welch said.

Dr. Barnett Kramer, a screening expert at the National Cancer Institute, said the report shows the limitations of mammography. "I wouldn't want to say it has had no effect but it certainly has not lived up to the anticipated effect," he said. For every tumor detected early because of mammography, "you would hope to see ... an equal reduction in metastatic disease, and that has not occurred."

The situation is very different with prostate cancer. The rate of advanced cases of that disease has been cut in half since screening with PSA blood tests came into wide use around 1988, and the average age at which men are diagnosed has fallen—from 72 to 70, the authors write. However, this does not prove PSA testing is good. Shifting the stage at which a disease is diagnosed is "only the first step for successful screening," which also has to save lives to be worthwhile, Welch said. "Just because you find something earlier doesn't mean you can change its course."

Again, Kramer agreed. Prostate screening, "when put to a definitive test, did not show a clear reduction in prostate cancer mortality" in large, rigorously done trials, he said. The government task force recommends against PSA testing, and says its risks outweigh its benefits for most men.

"Screening is a close call," Welch said. "My guess is few people are helped" by prostate or breast cancer screening while many are harmed by false alarms that trigger unnecessary tests and treatments, he said.

The original report, which also includes a discussion on prostate cancer and the PSA test, in the New England Journal of Medicine:  Trends in Metastatic Breast and Prostate Cancer — Lessons in Cancer Dynamics