Wisdom Wednesday: U.S. Cancer Treatment Guidelines ‘Often Based on Weak Evidence’

Cancer treatment guidelines produced by the US National Comprehensive Cancer Network (NCCN) are often based on low quality evidence or no evidence at all, finds a study published by The BMJ today.

The researchers, led by Dr. Vinay Prasad at Oregon Health & Science University, say their findings “raise concern that the NCCN justifies the coverage of costly, toxic cancer drugs based on weak evidence.”

These recommendations are used by US private health insurers and social insurance schemes to make coverage decisions, and guide global cancer practice, but it is not clear how the evidence is gathered or reviewed.

In the US, the Food and Drug Administration (FDA) approves all new drugs and grants new indications for drugs already on the market. The NCCN makes recommendations both within and outside of FDA approvals, but patterns of NCCN recommendations beyond FDA approvals have not been analyzed.

So Dr. Prasad and his team compared FDA approvals of cancer drugs with NCCN recommendation in March 2016 for a contemporary sample of drugs. When the NCCN made recommendations beyond the FDA’s approvals, the evidence used to support those recommendations was evaluated.

A total of 47 new cancer drugs were approved by the FDA for 69 indications over the study period, whereas the NCCN recommended these drugs for 113 indications, of which 69 (62%) overlapped with the 69 FDA approved indications and 44 (39%) were additional recommendations.
Only 10 (23%) of these additional recommendations were based on evidence from randomized controlled trials, and seven (16%) were based on evidence from phase III studies. Most relied on small, uncontrolled studies or case reports, or no offered evidence.

And almost two years after their analysis, the researchers found than only six (14%) of the additional recommendations by the NCCN had received FDA approval.

Obesity Linked to 13 Types of Cancer

A new study suggests that being obese or overweight was associated with cancer cases involving more than 630,000 Americans in 2014, and this includes 13 types of cancer.

“That obesity and overweight are affecting cancers may be surprising to many Americans. The awareness of some cancers being associated with obesity and overweight is not yet widespread,” Dr. Anne Schuchat, CDC deputy director, said during a midday media briefing.

The 13 cancers include brain cancer; multiple myeloma; cancer of the esophagus; postmenopausal breast cancer; cancers of the thyroid, gallbladder, stomach, liver, pancreas, kidney, ovaries, uterus and colon, the researchers said.

Speaking at the news conference, Dr. Lisa Richardson, director of CDC’s Division of Cancer Prevention and Control, said early evidence indicates that losing weight can lower the risk for some cancers.

According to the new report for the CDC and the U.S. Cancer Institute, these 13 obesity-related cancers made up about 40% of all cancers diagnosed in the United States in 2014. Although the rate of new cancer cases has decreased since the 1990s, increases in overweight and obesity-related cancers are likely slowing this progress, the researchers said.

Excluding colon cancer, the rate of obesity-related cancer increased by 7% between 2005 and 2014. During the same time, rates of non-obesity-related cancers dropped, the findings showed.

Can Frankincense Treat Cancer?

Frankincense oil is derived from the Boswellia tree. It has a long history in myth and folk medicine. In the Bible, it is one of three gifts offered to Jesus by the wise men, possibly because of its apparent healing powers.

Some supporters of herbal medicine argue that frankincense offers numerous health benefits. These supposed benefits include controlling bleeding, speeding up the wound-healing process, improving oral health, fighting inflammatory conditions such as arthritis, and improving uterine health.

Its most promising use may be as a cancer treatment. Cancer is a leading cause of death, killing 8.2 million people worldwide in 2012. Current research on the effectiveness of frankincense is limited, but early results are promising.

A 2006 study published in Planta Medica uncovered a number of ways the boswellic acid in frankincense might fight infection. Boswellic acid inhibited 5-lipoxygenase, a chemical involved in inflammatory processes. Researchers also found that boswellic acid might target free radicals and cytokines. Both of these play a role in inflammation. By disrupting inflammatory processes, frankincense could stop cancer before it starts.

The anti-inflammatory properties of frankincense suggest that it might also be effective in the treatment of diseases such as Rheumatoid arthritis, Crohn’s disease, Bronchial asthma and ulcerative colitis.

Some evidence suggests that frankincense might target cancer cells directly without harming health cells.

A 2009 study of bladder cancer studies how frankincense affected cultures of normal and cancerous bladder cells. The oil targeted cancerous cells, but it did not destroy healthy cells.

A 2015 study found similar effects in breast cancer. The researchers found that frankincense could kill breast cancer cells and disrupt the growth of future cancer cells.

Could Fish Oil Interfere With Cancer Care?

Fish oil supplements, and even certain fish, may hinder the effectiveness of cancer-fighting chemotherapy, a new study suggests.

Dutch researchers found herring, mackerel and three other fish oils increased blood levels of the fatty acid called 16.4(n3) in cancer patients. Experiments in mice have suggested this fatty acid makes cancer cells resistant to chemotherapy, the researchers said. But, it’s not certain that what was found to happen in mice would happen with human cancer patients.

Experts noted that research on whether fish oil hurts or helps cancer patients has produced mixed results.
“Dietary supplements are not necessarily benign,” said Dwight Kloth, director of pharmacy at Fox Chase Cancer Center in Philadelphia, who had no role in the new study. “There are numerous cases in the literature where nutritional supplements and herbal drugs have had deleterious interactions with chemotherapy.”

Many patients begin taking supplements after they receive a cancer diagnosis, but concern is growing that supplements might interfere with anti-cancer treatments, according to background information with the study.

“Our research shows that when you affect the membrane of cancer cells by altering the fats in the outer covering of the cell, you can make the membrane stiffer or more fluid,” explained Christine Mets, director of the Laboratory of Medicinal Biochemistry at the Feinstein Institute for Medical Research in Manhasset, N.Y.

“These fats can make it more difficult for chemotherapy to enter the cell or make the cell better at pushing the chemotherapy out of the cell,” added Metz, who wasn’t involved in the study.

The study authors and other experts said the new report, published April 2 in the journal JAMA Oncology, doesn’t prove that fish oil blunts chemotherapy’s effects in humans.

“Taken together, our findings are in line with a growing awareness of the biological activity of various fatty acids and their receptors and raise concern about the simultaneous use of chemotherapy and fish oil,” the researchers wrote.

“Until further data become available, we advise patients to temporarily avoid fish oil from the day before chemotherapy until the day thereafter,” the researchers added.

Random Mutations Responsible for About Two-Thirds of Cancer Risk

Although about one-third of cancers can be linked to environmental factors or inherited genes, new research suggests the remaining two-thirds may be caused by random mutations.

The new study was published January 1 in Science.

These mutations take place when stem cells divide, according to the study by researchers at Johns Hopkins Kimmel Cancer Center. Stem cells regenerate and replace cells that die off. If stem cells make random mistakes and mutate during this cell division, cancer can develop. The more of these mistakes that happen, the greater a person’s risk that cells will grow out of control and develop into cancer, the study authors explained in a Hopkins news release.

Although unhealthy lifestyle choices, such as smoking, are a contributing factor, the researchers concluded that the “bad luck” of random mutations plays a key role in the development of many form of cancer.

“All cancers are caused by a combination of bad luck, the environment and heredity, and we’ve created a model that may help quantify how much of these three factors contribute to cancer development,” said Dr. Bert Vogelstein, professor of oncology at the Johns Hopkins University School of Medicine.

Cristian Tomasetti is a biomathematician and assistant professor of oncology at the Johns Hopkins University School of Medicine and Bloomberg School of Public Health. “If two-thirds of cancer incidence across tissues is explained by random DNA mutations that occur when stem cells divide, then changing our lifestyle and habits will be a huge help in preventing certain cancers, but this may not be as effective for a variety of others,” Tomasetti suggested.

Simple Blood Test Could Be Used as a Tool for Early Cancer Diagnosis

Hypercalcemia is the most common metabolic disorder associated with cancer, occurring in 10-20% of people with cancer.

While its connection to cancer is well known, this study has, for the first time, shown that often it can predate the diagnosis of cancer in primary care.

The research, published in the British Journal of Cancer, analyzed the electronic records of 54,000 patients who had elevated levels of calcium and looked at how many of them went on to receive a cancer diagnosis.

Dr. Fergus Hamilton, who led the research from the Centre of Academic Primary Care at the University of Bristol, said: “All previous studies on hypercalcemia and cancer had been carried out with patients who had already been diagnosed with cancer – hypercalcemia was seen as a late effect of the cancer.”

“We wanted to look at the issue from a different perspective and find out if high calcium levels in blood could be used as an early indicator of cancer and therefore in the diagnosis of cancer.”

Analysis of the data found that in men, even mild hypercalcemia (2.6-2.8 moll/l) conferred a risk of cancer in one year of 11.5%. If the calcium was above 2.8 moll/l, the risk increased to 28%. In women, the risks were much less, with the corresponding figures being 4.1% and 8.7%.

In men, 81% of the cancer associated with hypercalcemia was caused by lung, prostate, myeloma, colorectal and other hematological cancers.

Organic Food Does Not Reduce Women’s Risk Of Cancer

Women who mostly or always eat organic foods have the same overall chance of developing cancer as women who never eat it.
Monday, March 31, 2014 (Medical News Today)

This comes from a new study from the University of Oxford and published in the British Journal of Cancer that followed over 600,000 middle-aged women for nearly a decade.

The word “organic” and the standards that apply to it are slightly different in various countries, but generally it forbids the use of synthetic pesticides and chemical fertilizers in the production of food.

Outside the organic movement, pesticides are widely used in agriculture, and there are concerns that residues from these get into the food chain and could increase the risk of cancer. But so far, the evidence for this is not strong enough to give any clear answers.

For this latest study, the researchers examined data on 623,080 middle-aged UK women being followed in the Million Women Study, a large national study of UK women’s health that is funded by Cancer Research UK and the Medical Research council.

The investigators asked women whether they ate organic foods, and over a 9-year period, looked at how many developed 16 of the most common types of cancer. The researchers could find no difference in overall cancer risk when they compared 180,000 women who said they never ate organic food with 45,000 who said they always or usually ate it.

When they looked in more detail at each of the 16 different cancers, the researchers found a slightly higher risk for breast cancer and a lower risk of non-Hodgkin lymphoma in women who said they mostly ate organic food. But they said this result could be due to chance and other factors.

Dr. Claire Knight, health information manager at Cancer Research UK, say the study adds to increasing evidence that eating organic food does not lower the risk of developing cancer, but she suggests people should wash their fruits and vegetables before eating them if they are worried about pesticide residue.

She points out that whether fruit and vegetables are conventionally grown or not, it is important to eat a well-balanced diet rich in fruits and vegetables to reduce cancer risk. “Scientists have estimated that over 9% of cancer cases in the UK may be linked to dietary factors, of which almost 5% are linked to not eating enough fruits and vegetables”, she said.

MY TAKE:
Although I agree with Dr. Knight, the key is eating a diet rich in fruits and vegetables, this is a flawed study. They did not access the quality of the diet itself. In fact, they relied of the subjects to qualify whether or not they ate “organic” foods and with what frequency. You need food journals as a minimum requirement and that is still too subjective. To qualify as a valid study the diet would have to be monitored. They even admit that variations in the risk for different cancers “could be due to chance and other factors”. A good study controls such factors.

I can not tell you how often I have watched people by junk food at the health food store. Just because it says “organic” does not make it healthy. Organic rice cakes are sugar. They just cost more.

The higher cost of organic food is justified. Organic seed can be over $100 a pound, where non-organic seed might be $4 a pound. All the equipment used in organic farming can not be used in non-organic farming. It takes a minimum of 5 years to convert from non-organic to organic farming. During that time, you have all the organic costs and yet can not sell your product as “organic”.

THE BOTTOM LINE:
The “dirty dozen” are foods that you should spend the extra money to buy: apples, celery, cherry tomatoes, cucumbers, grapes, kale, imported nectarines, peaches, peppers, spinach, strawberries, and summer squash.

The “clean fifteen” have little or no pesticide residual: asparagus, avocados, cabbage, cantaloupe, sweet corn, egg plant, grapefruit, kiwi, mangoes, mushrooms, onion, papaya, pineapple, sweet peas, and sweet potatoes. Don’t bother paying “organic” prices for these items.

Taking Vitamin D May Be Losing Its Shine

New Research On The Benefits Of Vitamin D Raises More Questions.
December 6, 2013

Researchers at France’s International Prevention Institute in Lyon analyzed data from several hundred observational studies and clinical trials examining the effects of vitamin D levels on so called non bone health – including links to illness such as cancer, diabetes and cardiovascular disease.

They found that the benefits of high vitamin D levels seen in observational studies were not replicated in randomized trials where participants were given vitamin D to see if it would protect against disease.

Lead researcher, Philippe Autier said “What this discrepancy suggests is that decreases in vitamin D levels are a marker of deteriorating health”. He explained that serious illness like cancer and diabetes may reduce vitamin D concentrations but that does not necessarily mean that raising vitamin D levels would prevent the illness from occurring.

MY TAKE:
After several years of being touted as the next cure all, opinions on vitamin D are beginning to swing back. You will continue to see more studies published that focus on the limitations of vitamin D, rather than the benefits. Vitamin C had a similar run during the 1970’s fueled by the claims of Linus Pauling. He recommended very large doses of vitamin C for every known disease on the planet. The Linus Pauling Institute, founded by him, has since refuted virtually every one on his claims. Today, vitamin C is recognized as an essential nutrient that is an important antioxidant in the body, but not a cure all. Vitamin D will eventually settle in its’ rightful place as well.

Vitamin D is a hormone, not a vitamin. Our body manufactures it from cholesterol (yes, that horrible fat that must be removed from the body by drugs) when sunlight strikes the skin, making vitamin D3. We also get vitamin D2 and D3 in the diet, primarily from oily fish. D2, and D3 are not really vitamin D, they are precursors and are transported to the liver and converted to 25-hydroxy vitamin D. However, it is still not truly vitamin D but rather a stable form that can be accurately measured on blood tests. Every cell in the body absorbs a little of this form, but much of it remains in circulation in the blood stream. The final conversion to true vitamin D occurs in the kidneys and 1,25-hydroxy vitamin D is produced and functions as a hormone controlling calcium metabolism.

Every cell also can make the final conversion, but that vitamin D remains in the cell where researchers believe it oversees protein replication from DNA. This is where all the questions remain. If vitamin D really acts like a librarian, selecting genetics like books in a library, its function could be vital to disease prevention. Currently, we can not measure vitamin D levels in the cell. In fact, we measure the precursor, 25-hydroxy vitamin D, in the blood because the final form, 1,25 hydroxy vitamin D, is used almost as fast as it is made, so blood levels change by the minute.

THE BOTTOM LINE:
Don’t give up on vitamin D. When the pendulum stops swinging, it will still have value. However, avoid the high level supplementation that has been so popular. Taking 50,000 IU of vitamin D is a massive overdose. It is using a vitamin as a drug. Stick with doses up to 4,000 IU per day unless you have blood work showing a true deficiency.