April 15-21, 2024
It is the National Cancer Prevention and Treatment Publicity Week
In cancer prevention and control, it is necessary to actively achieve the "four earlys", that is, early prevention, early detection, early diagnosis, and early treatment. "Early" means opportunity, it means life. In this issue, we focus on the topic of early screening for 6 types of cancer.
To prevent cancer, pay attention to early screening
With the deepening of medical research and the development of science and technology, the public has realized that cancer prevention is more important than cancer treatment.
Early cancer screening is an important part of scientific cancer prevention and treatment. A large number of scientific studies have shown that early cancer screening can improve the survival rate of patients and ultimately reduce the mortality rate. From 2000 to 2018, the age-standardized incidence of malignant neoplasms (a statistical indicator used to analyze the impact of a certain factor or disease on the health of a population) increased at a rate of 1.4% per year, but the mortality rate decreased at a rate of about 1.3% per year. In other words, despite the aging factor, the risk of death is declining despite the increasing number of cancer patients. This is mainly due to medical developments as well as early screening. New treatments such as targeted therapy and immunotherapy have greatly improved the treatment effect of patients, allowing patients with short survival time to survive for a long time and improve their quality of life, while early screening has enabled many patients to be early detection, early diagnosis and early treatment, and achieved good treatment results, such as lung cancer, colorectal cancer, breast cancer and other cancer patients.
It is often said that I am not feeling unwell, why should I go to the hospital for a check-up, but for screening, it is necessary to go to the corresponding test when there are no symptoms. Because there are often no obvious symptoms in the early stage of cancer, once symptoms appear, it may have progressed to the middle and advanced stages. Early cancer screening can detect cancer or precancerous lesions when there are no symptoms, and treat them in advance, thus greatly improving the probability of cure.
For cancers detected early and even precancerous lesions, the treatment plan is relatively simple, the prognosis of patients is also very good, and it can reduce the high medical costs and social resource consumption, and reduce the financial burden of patients and families.
In the face of the challenge of cancer, we must not sit idly by, but take proactive action to improve the chances of survival and quality of life through early screening and early treatment strategies. In addition, it should be combined with a healthy lifestyle to build a solid foundation for cancer prevention and control. In this process, the efforts of each individual are crucial, and every early screening is a cherishing and respect for life.
lung cancer
According to the summary of cancer registry and follow-up monitoring data in China, the 2022 malignant tumor prevalence data report released by the National Cancer Center shows that lung cancer is the first cause of malignant tumor morbidity and mortality in mainland China. According to data from the National Cancer Center's lung cancer screening team, the 5-year survival rate of patients with early-stage lung cancer screening can exceed 80%, and the curative effect can be achieved, and the benefits are obvious. Since there are no obvious symptoms in the early stage of lung cancer, patients can only be screened by taking the initiative to undergo physical examination, especially imaging examinations.
LDCT is the preferred choice for screening
At present, the most effective imaging test for early lung cancer screening in people at high risk of lung cancer is low-dose computed tomography (LDCT). Results from a 2011 national screening randomized controlled trial showed that LDCT reduced lung cancer mortality by 20% compared with chest X-ray screening. Therefore, LDCT is recommended for use in high-risk groups of lung cancer in both international and domestic guidelines.
High-risk groups should be screened regularly
According to the Guidelines for Low-dose CT Screening of Lung Cancer in China (2023 Edition), the high-risk group of lung cancer in mainland China is defined as 50~80 years old, with any of the following conditions attached.
Smoking history: 20 pack-years of smoking ≥ (number of packs of cigarettes per day × years of smoking), or passive smoking ≥for 20 years, or no more than 5 years if you have quit smoking now.
Have a history of long-term occupational exposure to carcinogens: such as long-term exposure to lung cancer carcinogens such as radon, arsenic, beryllium, chromium and their compounds.
Lung cancer in a first- or second-degree relative who smoked for 15 pack-years at the same time ≥ or passive smoker for ≥ 15 years.
If the above conditions are met, it is recommended to have an annual LDCT screening.
Studies have shown that the incidence of all cancer species has increased significantly from the age group of 35~39 years old, and the large number of domestic smokers has led to a large number of people exposed to second-hand smoke indoors or in the workplace, coupled with the influence of mixed factors such as special genetic phenotype, environmental factors, and cooking habits of Asian women, it is recommended that asymptomatic healthy people over 40 years old or who have been exposed to second-hand smoke for a long time who are more worried about their health and pay attention to their own health conditions should have at least one LDCT examination.
If you find an abnormality, you should seek medical attention in time
LDCT uses thin-slice scanning (1 mm thick image layer), so a large number of pulmonary nodules are detected (the detection rate can exceed 60%). Pulmonary nodules are found during physical examinations, and patients are prone to negative emotions such as nervousness and anxiety, so it is extremely important to consult the results of medical examinations in specialized outpatient clinics (such as pulmonary nodules consultation clinics) in specialized hospitals. In fact, the majority (more than 93%) of pulmonary nodules are benign nodules, so patients should not be too worried. However, if you are a high-risk group for lung cancer, you should go to the hospital for re-examination every year. If the nodule is slightly larger or temporarily indefinite based on the morphological features of the image, it can be re-examined after short-term or regular respiratory treatment as described in the LDCT diagnostic report, or further examination, such as needle biopsy guided by contrast-enhanced CT, as recommended by the specialist outpatient doctor.
Colorectal cancer
Colorectal cancer is one of the common malignant tumors and poses a serious threat to human health. Early screening is an effective means to reduce the incidence and mortality of colorectal cancer, and it is also an important prevention and treatment strategy.
Colonoscopy is the "gold standard"
There are a variety of methods available for colorectal cancer screening, the most commonly used screening methods are fecal immunochemical testing (FIT) and colonoscopy.
FIT has good sensitivity and specificity, and has become the most widely used early screening technology for colorectal cancer, and the recommended screening frequency is once a year.
Multi-target fecal FIT-DNA detection is a detection method combining fecal DNA detection technology and FIT, which is recommended for early diagnosis and screening of colorectal tumors in asymptomatic populations, and the screening frequency is once every 1~3 years.
Patients with a positive stool test should undergo colonoscopy. Standardized colonoscopy is the "gold standard" for colorectal cancer screening, and at the same time, it can confirm the pathological diagnosis.
Screening methods vary from population to population
Colorectal cancer screening can be tailored to different individuals and populations or a combination of different techniques to achieve the minimum cost and maximum benefit. The screening population is divided into the general population and high-risk groups.
General population It is recommended that the general risk group start screening at the age of 40 and have a colonoscopy every 5~10 years or a FIT examination once a year; people aged 76~85 years old can choose whether to participate in the screening according to their personal health status, life expectancy and previous screening results; and people over 85 years old will not be screened.
High-risk people People who are at high risk of colorectal cancer or a family history of certain polyps can change the age at which screening begins and how often they are screened. The recommended screening regimen is to start at age 40, or 10 years before the earliest member of the family with colorectal cancer, and have a colonoscopy every 5 years.
Abnormalities should be treated as soon as they are detected
The main purpose of colorectal cancer screening is to detect precancerous lesions, advanced adenomas and early-stage cancers, and early detection and early intervention are very effective means.
If abnormalities are found on colonoscopy, a tissue biopsy should be taken to confirm the diagnosis. Colonoscopic polypectomy reduces the incidence of subsequent colorectal cancer. For most people who undergo polypectomy, the interval between colonoscopy reviews should be determined based on the pathological nature, size, and number of polyps, for example, every 1, 3, or 5 years.
Cancer may be detected early during screening colonoscopy. If the lesion biopsy pathology shows high-grade intraepithelial neoplasia, it should be further determined by colonoscopy or endoscopic ultrasound, and if the lesion does not have deep submucosal invasion and regional lymph node metastasis, endoscopic resection may be recommended, otherwise surgical intervention may be required.
hepatocarcinoma
The liver is hidden deep in the abdominal cavity, and its volume and spatial elasticity are relatively large, so the symptoms of patients with early liver cancer are not obvious or do not have any discomfort. Many patients with liver cancer have jaundice, ascites and other symptoms when they have intermediate and advanced liver cancer, with poor prognosis and short survival time. Early detection and treatment are essential to improve the cure and survival rates of patients.
There are 4 early screening methods
At present, the early screening methods for liver cancer mainly include the following.
Liver function tests Blood tests are performed to understand the metabolism, detoxification, and excretion functions of the liver, and abnormal liver function is found.
Alpha-fetoprotein (AFP) testing AFP is a tumor marker commonly used in liver cancer screening. When liver cancer occurs, AFP levels are significantly elevated. Liver cancer can be detected early by regular testing for AFP.
Ultrasonography Ultrasonography is currently the preferred method for screening liver cancer. Ultrasonography has the advantages of convenience, real-time, non-invasive, radiation-free, and low price, which can observe the morphology, structure and blood flow of the liver, find space-occupying lesions in the liver, and preliminarily judge the benign and malignant tumors.
CT and Magnetic Resonance Imaging (MRI) CT and MRI can accurately observe the location, size, and extent of liver lesions, which can help diagnose and stage liver cancer.
3 types of people should pay attention to early screening
People with liver disease are people with hepatitis B and/or hepatitis C. Studies have shown that long-term stimulation of hepatitis B virus or hepatitis C virus is the main factor that induces liver cancer. The second is the population of non-alcoholic steatohepatitis. Fatty liver can be transformed into hepatitis and cirrhosis, which in turn can lead to liver cancer. The third is people with cirrhosis. 85%~95% of liver cancer patients suffer from liver cirrhosis at the same time.
People with unhealthy lifestyles are people who drink excessively. Long-term excessive alcohol consumption increases the incidence of liver cancer. If hepatitis B or C is combined, the incidence of liver cancer will increase exponentially. The second is people who eat smoked, pickled and moldy food for a long time. These foods contain carcinogens that can induce liver cancer. The third is people who have bad habits such as staying up late for a long time, overwork, and smoking.
People with a family history of liver cancer Liver cancer is not inherited, but some liver cancers run in families.
It should be noted that if there is an abnormality in the liver cancer screening, such as liver tumor or abnormal tumor indicators in the examination, it is necessary to go to the hospital in time.
After a liver tumor is found, further tests may be needed to confirm the diagnosis and understand the specifics of the lesion. Once liver cancer is diagnosed, it should be treated aggressively according to the doctor's advice.
gastric cancer
Gastric cancer is one of the most common malignancies in mainland China. Early prevention, early detection and early treatment are the main strategies to reduce the mortality rate and improve the survival rate of gastric cancer.
Gastric cancer screening is recommended for people at high risk of gastric cancer. There are two ways to be screened.
Gastroscopy Gastroscopy is the most effective way to detect early-stage stomach cancer. During the examination, the doctor usually needs to administer a local anesthetic to the patient, and then pass a flexible gastroscope through the mouth into the patient's esophagus, stomach and other parts. Through the camera at the top of the gastroscope, the doctor can directly observe the shape, color, and vascular distribution of the gastric mucosa, and find inflammation, ulcers, tumors and other lesions. During gastroscopy, the doctor can also remove the suspicious tissue from the patient and send it to the pathology department for testing to determine the nature of the lesion. Overall, gastroscopy is a safe and accurate examination method, which is of great significance for the diagnosis and treatment of gastric diseases.
Helicobacter pylori detection Helicobacter pylori is one of the few bacteria that can survive in the stomach, which can colonize the stomach for a long time, causing chronic gastric mucosal inflammation, destroying gastric glands, and then leading to intestinalization of the gastric mucosa, and eventually causing cancer.
The most commonly used test for H. pylori is a urea breath test. During the examination, urea is taken orally, and the urease produced by Helicobacter pylori will hydrolyze it into NH3 and CO2, which will then diffuse into the bloodstream and be excreted by the lungs. This method is easy to operate, and the sensitivity and accuracy of detection are good.
How to determine whether you belong to the high-risk group of gastric cancer? If you are ≥ 45 years old and meet any of the following conditions, you can be judged to be a high-risk group of gastric cancer.
1. Long-term residence in an area with a high incidence of gastric cancer.
2. Presence of Helicobacter pylori infection.
3. Precancerous diseases such as chronic atrophic gastritis, gastric ulcer, gastric polyps, postoperative residual gastritis, hypertrophic gastritis, pernicious anemia and so on.
4. First-degree relatives have a history of gastric cancer. There are other high-risk factors for gastric cancer, such as long-term intake of high salt, pickled diet, smoking, excessive alcohol consumption, etc.
If it can be detected early and treated in time, the survival rate of gastric cancer patients can be greatly improved. Maintaining a healthy lifestyle, regular check-ups, and early medical attention are essential to prevent and treat stomach cancer.
breast cancer
Early prevention and high-risk screening of breast cancer are the keys to improving treatment outcomes. If early detection and standardized treatment are achieved, the 5-year survival rate of patients with early-stage breast cancer can reach 90%.
Breast imaging is an "early screening tool"
Breast imaging can improve the early diagnosis rate of breast cancer and reduce the mortality rate of breast cancer.
Mammography for breast cancer screening can significantly reduce breast cancer mortality.
Different from mammography, breast ultrasound is a non-invasive, radiation-free, and easy-to-operate examination method, and is the first choice for adolescent, pregnant and lactating women. Breast ultrasonography is not affected by gland density. Studies have shown that breast ultrasound, as a supplement to mammography, can improve the sensitivity and detection rate of breast cancer screening, and can detect more early-stage breast cancer.
High-risk people may have an MRI of the breast as recommended by their doctor. Breast MRI is one of the most high-resolution soft tissue examinations and has many advantages over X-ray and ultrasound. In addition, breast MRI is used to evaluate tumor necrosis and fibrous tissue hyperplasia after neoadjuvant chemotherapy, but it is not suitable for patients with a pacemaker and metal (eg, cardiac stents) in the body.
People who want to be screened for breast cancer
The relevant guidelines in mainland China suggest that the starting age for breast cancer screening in general risk groups is 40 years old, and it is recommended that women aged 45~49 do mammography for screening.
People at high risk of breast cancer can be screened earlier than the age of 40. Among them, women with relatives (such as mothers, sisters, etc.) with breast or ovarian cancer should pay more attention to breast cancer screening, especially women with a family genetic history. Patients with BRCA1 and BRCA2 mutations and their immediate family members should be screened for breast cancer regularly because these mutations increase the risk of breast and ovarian cancer.
Women who have had breast cancer need regular screening to detect possible recurrence or new tumors as early as possible.
Women who have been using hormone replacement therapy for a long time have a higher risk of breast cancer and should be screened regularly.
Women who are nulliparous or late in childbirth and who are not breastfeeding have a relatively high risk of breast cancer and need to be screened regularly.
Do this for breast self-examination
In addition to regular physical examinations, women can also detect abnormalities through breast self-examinations.
Women can have a monthly breast self-exam, preferably within a week after menstruation.
During the self-examination, if you find that there are high-risk conditions for breast cancer such as bilateral breast unequalization, skin dimpling, redness and swelling, nipple erosion, inversion, palpable lump, and nipple discharge, you should go to the hospital in time.
Cervical cancer
Cervical cancer is a common malignancy of the female reproductive system that endangers women's health and is caused by high-risk human papillomavirus (HPV) infection. Regular cervical cancer screening can detect precancerous lesions and early-stage cancers early, improving the cure rate and survival rate of patients.
There are 4 screening methods
1. HPV nucleic acid detection, with high sensitivity and good negative prediction, is the preferred method recommended by the guidelines.
2. Cervical cytology, also known as liquid-based thin-layer cytology (TCT).
3. Combined screening refers to HPV nucleic acid detection combined with cervical cytology. Cytology has a high specificity and positive predictive value but low sensitivity, and HPV nucleic acid detection has a high sensitivity and negative predictive value but low specificity. The combination of the two can complement each other's strengths.
4. Visual screening method refers to the visual inspection of acetic acid test and the visual inspection of compound iodine solution.
Be screen-conscious
General population: Women aged 25~64 should have HPV nucleic acid testing alone or combined screening every 5 years, or cervical cytology examination every 3 years. Women over the age of 65 who have had adequate prior negative screening and no high-risk factors such as cervical intraepithelial neoplasia, persistent HPV infection, and no history of treatment for HPV-related diseases can discontinue screening, and cervical cancer screening should still be performed if they have never been screened, or if there is no adequate negative screening record in the 10 years prior to the age of 65, or if clinically indicated.
Special populations Women under the age of 25 with a history of multiple sexual partners, early sexual activity, human immunodeficiency virus (HIV) infection, and high-risk factors such as smoking should pay attention to screening. The goal of cervical cancer screening in pregnant women is to rule out cervical cancer. Screening during pregnancy is safe and does not pose a risk to the health of the mother and fetus. Women who have undergone a hysterectomy should pay attention to screening. Women who have had their uterus removed due to precancerous uterine lesions have a 2~5 times higher risk of invasive cancer of the cervix than the general population. Immunocompromised people should pay attention to screening. Patients with autoimmune diseases are at higher risk of HPV infection, cervical cancer and precancerous lesions due to long-term immunosuppression, resulting in immunosuppression.
Treatment should be directed by a doctor
If cervical cancer screening reveals abnormalities, the response depends on the patient's specific condition and the doctor's recommendations.
1. Regular re-examination According to the comprehensive evaluation of HPV detection and cervical cytology examination results, patients can pay attention to the observation of screening abnormalities with a low probability of cancer, and go to the hospital for regular re-examination.
2. Medication If vaginal inflammation is found, the patient can take medication and improve the body's immunity.
3. Colposcopy If the screening results show the presence of precancerous lesions or early-stage cancer, the doctor will recommend colposcopy and, if necessary, a cervical biopsy, and decide on the method of further treatment based on the biopsy results.
Text: Zheng Ying and Zhou Changming, Fudan University Cancer Hospital, Tang Wei, Department of Imaging Diagnosis, Cancer Hospital, Chinese Academy of Medical Sciences, Meng Wenjian, Colorectal Cancer Center, West China Hospital, Sichuan University, Luo Xiaojun, Hepatobiliary and Pancreatic Tumor Center, Chongqing University Cancer Hospital, Li Jialin, Gastrointestinal Cancer Center, Peking University Cancer Hospital, Zhang Jin, Breast Cancer Prevention and Treatment Research Center, Tianjin Medical University Cancer Hospital, and Tian Xiaofei, Department of Gynecologic Oncology, Shaanxi Cancer Hospital
Editor: Liu Yang, Yang Zhenyu
Proofreader: Li Shiyao
Review: Guan Zhongyao, Xu Bingnan