How can cure cancer
And while cigarette use is the most important risk factor for cancer worldwide, cancer-causing infections, such as hepatitis and the human papilloma virus HPV —both preventable with vaccines—account for up to 25 percent of cancer cases in some low- and middle-income countries. These shifting sands of causation are also evident in the United States. Over the past 25 years, while cancer deaths have risen in number as the population grows, the cancer death rate has steadily declined.
As of , the cancer mortality rate for men and women combined had fallen 27 percent from its peak in The engine behind this impressive public health feat was the decline in smoking, though early detection and improved treatments also played a role.
In , 42 percent of U. Lung cancer death rates declined in tandem, falling 48 percent from to among men and 23 percent from to among women. That public health victory is now in peril.
In the next five to 10 years, experts say, the cancer-causing effects of obesity could actually reverse the downward trend ushered in by the decline in smoking. Indeed, obesity could soon become the number-one risk factor for cancer in the United States and eventually around the world. In the U. Obesity is a well-established risk factor for at least 13 cancers.
Increasing obesity among younger people may portend a bigger wave of cancer in the near future, according to the The Lancet Public Health study. These cancer cases serve as sentinels for future disease in older people.
Two kinds of prevention can substantially reduce cancer deaths. The first, and most important, is primary prevention: averting a malignancy by attacking its causes and promoting the factors that protect against it.
Taxes on cigarettes and alcohol, vaccination against cancer-causing pathogens such as HPV and hepatitis B, promoting healthy eating and regular exercise: All are examples of primary prevention. Primary prevention works when social and economic conditions, the built environment, and the public health and medical systems work in concert to support it. Secondary prevention has helped bring down death rates of breast, cervical, and colorectal cancers, among others.
Long-term epidemiological studies have clarified which cancers are preventable and by how much, if specific risk factors were reduced. It noted that for cancers in which most of the driving genetic mutations are caused by the environment—such as lung cancers, melanomas, and cervical cancers—85 to percent of new cases could be eliminated through smoking cessation, avoidance of ultraviolet radiation exposures, and vaccination against HPV, respectively.
Even individuals at high inherited genetic risk for cancer can benefit from lifestyle change, adds Peter Kraft , professor of epidemiology at the Harvard Chan School. In fact, the women who had the highest nonmodifiable risk but also kept their weight down, did not drink or smoke, and did not use menopausal hormone therapy had about the same breast cancer risk as an average woman in the general population.
In fact, high-risk individuals are the people who seem to reap the biggest benefit from adopting healthy lifestyles. Should anyone still doubt that many cancers are preventable, the inarguable proof is how the disease plays out over time and space. Cancer rates and types can starkly change within a country and starkly vary between countries. These variations are not genetic—a small minority of cancers are directly attributable to known, death-dealing DNA mutations.
Rather, they reflect external—and, in principle, modifiable—risk factors. For example, lung cancer eclipsed all other cancers during most of the 20th century in the United States because per capita cigarette consumption shot up from 54 cigarettes a year in to 4, cigarettes in , then fell to 2, in The initial upward trend was powered by corporate profiteering. The downward slope was powered by the landmark U.
Another instance of a breathtaking prevention success within a country took place in the s and s in Taiwan, which saw an 80 percent decline in liver cancer rates in birth cohorts that received hepatitis B vaccination early in life. The most common causes of liver cancer are infection with the hepatitis B virus in Africa and East Asia, and the hepatitis C virus in the U.
And Australia recently reported it is on course to completely eliminate cervical cancer in the coming decades through vaccinations. The spatial dimension of cancer is equally revealing. When racial or ethnic groups migrate from one part of the world to another, their cancer risks quickly take on the local patterns.
Between and , for example, numerous studies looked at cancer incidence in U. Caucasians, immigrant groups, and matched controls. Among the populations studied were first- and second-generation Japanese immigrants, Asian American women, Vietnamese Americans, and Hmong refugees from Vietnam, Laos, and Thailand.
But over subsequent generations, their cancer patterns became distinctly American. This was especially true for cancers related to hormones, such as breast, prostate, and ovarian cancers, and to cancers attributable to Westernized diets, such as colorectal malignancies. Given the fact that many cancers can be averted, what would it take to make the dream of prevention a reality?
First, scientists say, we must understand the earliest biological events that give rise to the birth of a cancer cell.
So, how is cancer initiated? What are the brakes on early cancer? What are the challenges that the cancer cell faces in becoming a cancer cell? How does the cancer cell remove enough of those brakes so that it will become malignant? Another biological unknown is the role of the microbiome—the trillions of microbes in and on our bodies—in human cancer. One intriguing culprit on which Garrett and her colleagues are focusing is Fusobacterium nucleatum , normally a microbial denizen of the mouth.
The microbiome is proving to be a vast and inviting landscape in cancer biology. In humans, gum disease caused by bacterial infections has been connected to higher risk of pancreatic cancer. In mice, lung tumors appear to alter nearby bacterial populations to help the tumors thrive—and antibiotics appear to shrink the tumors. Experiments in mice have even linked a disrupted gut microbiome to greater risk of invasive breast cancer.
Now we know: the bacterium Helicobacter pylori. With many tumors, there is a lag time of 20 years or more between the development of the first cancer cell and the onset of end-stage metastatic disease. Among these promising biomarkers are proteins that signal early tumors, DNA or RNA, small molecules, circulating tumor cells, immune cells, and other infinitesimal biological entities. Sangeeta Bhatia, a biomedical researcher and early-detection pioneer, and the John J. Her lab is searching for highly specific biomarkers for often-elusive tumors of the ovary and lung and in colon metastasis.
Clinical trials for the technology will begin later this year. Other scientists envision, in the more distant future, continuous monitoring of cancer risk through smart toilets, wearables such as diagnostic imaging bras, and other passive and noninvasive technologies. However, in some cases, the tumor cells then develop the ability to make testosterone from cholesterol. The mapping of the human genome in — a historic international achievement in which Roswell Park played a role — contributed vast amounts of information for solving the puzzle.
It has helped researchers identify genes associated with cancer risk and made possible such breakthroughs as genomic analysis, which matches the DNA of the patient and the tumor to the targeted therapies that are likely to work best.
And immunotherapy , once viewed as having limited potential, is showing great promise, especially with the development of new cellular therapies. Twenty years ago, the disease would progress in early-stage patients. Now we know how to treat an early-stage patient. The key is increasing the number of patients we can help and making those treatments better. Every day patients survive who would not have survived even five years ago. Every day patients are being cured with new advances that are coming along the line.
Return to homepage. So, why do we continue to attempt to treat one of the most deadly diseases with methods that are mediocre at best? According to a team of researchers from the University of Washington, artemesinin , a derivative of the wormwood plant that is commonly used in Chinese medicine, can kill 12, cancer cells for every healthy cell.
So far, this herb is not yet available for cancer treatment in humans, but it is in the works. The diseased cells recognize the herb as a natural, harmless protein. So, they let it in willingly, where it then proceeds to destroy the city, killing 12, cancer cells for every healthy one.
This means that it could be manufactured into a drug with minimal side effects. According to the Lai, human trials are still several years away, but he is hopeful that the artemisinin compound can be cheaply manufactured since the herb is so readily available.
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