EVIDENCE-BASED MEDICINE IS ADVANCING BY LEAPS AND BOUNDS , and almost everyone has access to sites with correct information - but the word "cancer" remains frightening. Many tumors have long ceased to be a death sentence, especially in the case of early diagnosis. Nevertheless, cancer diseases are surrounded by a huge number of myths, conjectures and horror stories - and we tried to refute a dozen of them.
We have an epidemic of cancer
Indeed, in developed countries, oncological diseases occupy one of the first places among the causes of death of the population, catching up only with cardiovascular diseases or even ahead of them. At the same time, cancer is still a rather rare disease, different types of which are diagnosed only in a few dozen out of 100 thousand people a year. The catch is that the tumor develops due to a series of genetic mutations in a single cell - these mutations lead to its uninterrupted division bypassing the body's stop signals.
Cells become resistant to apoptosis (the so-called “programmed” death), new blood vessels begin to attract tumors to feed the tumor, and also penetrate into other organs and tissues - they metastasize. Often it takes years and decades. According to statistics , 77% of people with malignant tumors, they occur after 55 years. It is not surprising that in countries where the absolute majority of people are experiencing this threshold, oncology is widespread.
People used to not have cancer
The term "cancer" appeared in the fifth century BC thanks to Hippocrates. Traces of malignant tumors at different times were found in the mummies of ancient Egypt , Peru and Chile , in the bones of ancient Romans , in medieval cemeteries in England and Portugal . The King of Naples, Ferdinand I, died five hundred years ago from colon cancer that had been neglected , and a notable Scythian warrior, whose rich tomb was found in 2001 in the territory of the modern Republic of Tyva, had prostate cancer .
In other words, cancer with people was long ago, and even our distant ancestors did not escape it. On the only known remains of a Kanam man (Homo kanamensis) and another not yet named proto-man, they found signs of a malignant bone tissue tumor - osteosarcoma. By the most conservative estimates, about 200 cases of fossil cancer are described. It is worth making an amendment to the fact that many of the remains are only partially preserved, and targeted searches for cancer do not lead to them even now.
People used to have cancer less often
It is difficult to confirm or deny this item impartially. In addition to the fact that advances in medicine have allowed people to survive to cancer, the massive spread of smoking and obesity also did not improve the situation. But it cannot be argued that before cancer was extremely rare. The English paleontologist Tony Waldron studied the death register for the years 1901-1905 and found out that the probability of finding signs of cancer in the bone remains of men is 0–2%, and in women - 4–7%. At the same time, only primary bone tumors can be found directly in the bones - this is less than 0.2% of all cancers, as well as metastases of some other types of cancer. Soft tissue tumors in the remains, from which only the skeleton is preserved, are usually impossible to detect.
Later, scientists from Munich obtained the same results : using special equipment, they found five cases of cancer among 905 skeletons in Egyptian necropolises and thirteen cases in 2547 remains at a medieval cemetery in Germany. This suggests an interesting conclusion: although life in ancient Egypt and medieval Europe was different, people were equally sick with cancer.
Cancer is younger
From a statistical point of view, this is true: according to a recent conclusion from the International Agency for the Study of Cancer, over the past twenty years, their prevalence in children has increased by 13%. But everything is not as simple as it seems - and, fortunately, cancer in children remains an extremely rare disease (about 14 cases per 100 thousand children per year).
Scientists tend to believe that such an increase in prevalence is primarily the effect of more accurate diagnosis and high awareness. Perhaps in the future the numbers will increase: today's data covers 100% of children in North America and Europe and only 5% in Africa and Asia. In poorer countries, cancer in children is most likely simply not diagnosed.
Wild animals do not get cancer
All animals are ill with cancer: both wild, and domestic, and especially laboratory. Most often, tumors are diagnosed in domestic animals - there are many of them and they are subject to veterinary control. In addition, they are often the victims of closely related crosses that increase the likelihood of the transfer of defective genes to descendants. Wild animals also have oncological diseases. The population of Tasmanian devils - a marsupial mammal from Australia - is on the verge of extinction because their cancer has evolved and is able to spread through bites.
The myth that there are animals that do not get cancer is massively spread twice. The first time was when scientists noticed that the cartilage tissue does not contain vessels, and decided that it contains some substances that inhibit their growth. The most important feature of malignant tumors is the formation of new blood vessels, so the scientists decided to study the corresponding properties of cartilage tissue. True, they were ahead of the charlatans who flooded the market with shark pills: the shark's skeleton consists entirely of cartilage.
The second time the scientific community became a victim of the myth. Attention attracted naked cattle - small rodents, which differ in phenomenal life expectancy, up to thirty years. On this wave, Russian scientists even received a prestigious award for uncovering the mechanism of naked excavators' resistance to cancer, but after a couple of years, these rodents also had oncological diseases.
Can get cancer
Extremely seductive theory that cancer is an infectious disease, in the sixties of the last century, cost the United States National Cancer Institute hundreds of millions of dollars spent almost wasted. In fact, it is now known that there are viruses capable of provoking the development of certain types of cancer : the human papilloma virus causes cervical , anus, penis and pharynx cancer, hepatitis C virus - liver cancer, and Epstein - Barr virus - Burkitt's lymphoma.
People can become infected with cancer only by direct transfer of tumor cells from the donor to the recipient - for example, in the process of organ transplantation. True, even two thirds of such cases end with the fact that the immune system of the new host kills the implanted tumor.
The main cause of cancer is chemical carcinogens.
At one time, bacteriologist Bruce Ames invented a test that allows one to study the effects of chemicals on the genetic apparatus using bacteria, that is, to determine the carcinogenicity of these substances. Talk about chemical carcinogens caused a great public outcry and affected all industries. True, later Ames partially rehabilitated artificial chemical compounds: it turned out that natural substances may have the same properties. Of the 28 natural substances that a cup of coffee contains, 19 are vegetable carcinogens. However, they can cause the development of a tumor only in large quantities, and it is possible only in laboratory animals.
Chemical carcinogens and justifies the history of American Pripyat - the town of Love Canal , built on a dump of toxic waste. For thirty years of a retrospective study , no outbreak of cancer was detected in ex-residents. The residents and liquidators of Chernobyl also did not find anything , excluding the more frequent thyroid cancer in children and adolescents: its development was associated with food contamination with radioactive iodine in the first months after the disaster.
In fact, the main carcinogens have long been known - it is ultraviolet radiation, components of cigarettes and alcoholic beverages. Other important risk factors are obesity and some infections. Chronic exposure to cigarette smoke and other lifestyle elements are much more important than any parabens in cosmetics whose carcinogenicity has been demonstrated only in the laboratory.
Pharmaceutical companies are not profitable to invent a cure for cancer
It is impossible to find a single cure for cancer, if only because cancer is the common name for a huge group of diseases. Moreover, breast cancer alone is hundreds of different diseases. Cancer is individual, as the individual organism of each individual is individual, like fingerprints . The current trend in oncology is the so-called precision medicine, which allows you to choose a personal medicine or treatment regimen for each patient based on specific biomarkers.
Billions of dollars are invested in drug development, and it is still profitable for pharmaceutical companies - in terms of both finance and reputation. For many malignant tumors, effective treatment already exists - but for the reasons described above, it does not suit everyone.
We have no progress in cancer treatment.
Over the past ten to twenty years, overall cancer mortality in various age groups has decreased by 1% every year - and this trend is noted throughout the world. The exception was lung cancer in women - the result of the fashion of the seventies on "female" cigarettes, and also liver cancer - the result of the massive spread of infection by the hepatitis C virus.
Cancer is impossible to beat
Of course, it is better to warn rather than win. Cancer prevention includes a number of simple requirements : it is necessary to eliminate smoking, reduce alcohol consumption and red meat, eat enough vegetables and fruits, monitor body weight, be physically active and protect the skin from sunburn.
In the early stages, cancer is curable - true, and difficult to identify, because it does not manifest itself. On the website of the Cancer Prevention Foundation, you can be tested for personal risks and understand when to turn to oncologists. Cancer in the later stages is most often impossible to cure, but in many cases, treatment can restrain its progression. Cancers become chronic, and people have lived with them for decades - so in a certain sense, we won the cancer.
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