According to the report on the incidence and death of new cancers in China in 2016 years released by the National Cancer Center, the number of new cancer cases in that year was close4.0ten thousandCancer deaths240余萬Example. To convert that, in just 2016 years,平均每天就大約有超1萬人確診癌症。
As the cause of more than 9 percent of cancer patients' eventual death,"Cancer metastasis"It's every cancer patient's nightmare.
So, how exactly do cancer cells metastasize? What are the symptoms?
OneHow does cancer metastasize? Why are cancer cells so hard to destroy?
At present, the mechanism of cancer metastasis is not clear in the medical community, and cancer metastasis is an extremely complex process with multi-step and multi-factor participation, which needs to be passed in the middleLocal infiltration, circulatory spread, and distant invasionand so on. Moreover, the metastasis of tumors does not occur randomly, and the sites that are prone to metastasis are different for different tumors, and metastasis is mainly passedLymphatic, hematogenous and implantationand other ways.
Once cancer cells appear in the body, they are like they can't be killed"Xiaoqiang" is average, and he can't kill it all, why is this?
Ba Yi, Director of the Cancer Center of Peking Union Medical College HospitalIt is pointed out that the current common theory is the stem cell hypothesis. After treatment, most of the cancer cells in the cancer patient's body die.However, there are still a small number of "fish that have slipped through the net"What remains of these are cancer stem cells. These cells have:Self-renewal, infinite proliferationand resistance to therapeutic drugs, which greatly increases the risk of cancer metastasis.
In addition to the stem cell hypothesis, there are scientists who believe that there are theCancer cells have:"Dormancy" ability, epithelial-mesenchymal transition hypothesis, seed-soil hypothesisand other related conjectures. But there are complex biological mechanisms behind all hypotheses, and it is not clear what causes them.
TwoOnce the cancer has spread, the body may send it out5alerts
When cancer metastasizes, the body may appear a series of abnormal signals, and these symptoms must be vigilant:
Unusual pain
Pain is one of the more common symptoms in cancer patients, especially when the cancer has metastasized to the bone. Because cancer cells will infiltrate nerve tissue, compress the lumen of the body, and then cause tissue necrosis, inflammation, and obvious pain symptoms.
Bleeding of varying severity
Tumor necrosis causes local bleeding in the body, in which case the amount of bleeding is generally small. When the tumor invades the surrounding blood vessels, it will cause inflammation and heavy bleeding, manifested as hematemesis, melena, vaginal bleeding and blood in the urine.
Swollen lymph nodes
Lymph node metastasis is one of the main ways of cancer metastasis, and cancer patients with abnormal lymph node enlargement after treatment need to be highly vigilant due to lymph node metastasis.
Unexplained wasting
Cancer cells consume a lot of nutrients during the proliferation process, which in turn prevents normal cells from getting enough nutrients, resulting in significant weight loss.
Unexplained low fever
The growth of cancer cells is out of the body's control, it will constantly squeeze the living space of normal cells, and after the cells die, they will be absorbed by the body and cause the body to heat up. The temperature at which the heat is generally heated is in38Below °C, it is difficult to reduce fever with antipyretics, or fever recurs soon after it has subsided.
ThreeStudies have shown that everyone has cancer cells, so why doesn't everyone get cancer?
When it comes to cancer, everyone is afraid of it, but in fact, there are cancer cells in each of us. According to a study in Cancer Research,Everyone has cancer cells and genes in their bodyExist.
Our body is metabolizing 100 hours a day, and about 0 billion new cells will be produced, and in the process of producing new cells, it is inevitable that there will be errors in DNA replication, so there may be some of them20~0cancer cells appear。
But our body's immune system is also very strong, and it usually recognizes the cells that are mistakenly replicated in time to curb their development. So even if there are cancer cells in the body, not everyone will get cancer. But whenWeakened immune system function, it may allow cancer cells to take advantage of the opportunity to replicate in the body and induce cancer.
In addition, many cancer patients are diagnosed with advanced cancer once they are diagnosed, and they lose the opportunity for surgical treatment. Therefore, early prevention and detection are the top priorities, so how to prevent cancer"Asymptomatic period"?
Zhang Kai, Deputy Director of the Department of Cancer Prevention, Cancer Hospital, Chinese Academy of Medical SciencesIt is pointed out that many cancers have no obvious symptoms in the early stage, or the symptoms are not specific, which is easy to be ignored. If you want to detect cancer early, the most important thing is to do it in timeCancer check-upDifferent cancers need to be screened differently, so you must choose a screening plan that suits you according to your specific situation, and you must take the initiative to learn to screen. Rather than waiting until symptoms have developed to get screened, it's often too late.
The occurrence of cancer is not traceless, so it is necessary to observe the physical manifestations in daily life and seek medical examination in time after discovering abnormalities.
參考資料:
[1]How tumors metastasize.Outpatient Department of Hebei Institute of Disease Control and Medical Sciences.02-0-0
[2]《Everyone has an oncogene! Do you know how often you get cancer?》. Sichuan Cancer Hospital.25-0-0
[3]《6This kind of manifestation indicates that the cancer cells in the body have spread, so do well4point, which can effectively prevent cancer recurrence! 》.Oncology of the Third Affiliated Hospital of Guangdong Pharmaceutical University.19-0-0
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