Nasopharyngeal carcinoma is a malignant tumor with a specific geographic and ethnic distribution worldwide, commonly found in southern China and Southeast Asia, North Africa and Alaska Eskimos. The world average incidence rate is less than 1 per 100,000, and the 2009 WHO incidence rate in China was 2.54 per 100,000, with a mortality rate of 1.35 per 100,000. The incidence rate of nasopharyngeal carcinoma in 2010 was 26.49/100,000 in Sihui City, Guangdong Province, with 38.95/100,000 males and 14.01/100,000 females, which is 1.4-2.0 times higher than that of females, and is the only tumor with the local name “Guangdong tumor”. The epidemiology of nasopharyngeal cancer in 2012, WHO estimated that there were 86,000 new cases of nasopharyngeal cancer and 51,000 deaths worldwide, of which 80% came from Asia and 5% from Europe, with about 33,000 new cases (38%) and 20,000 deaths (40%) in China each year. China is mainly concentrated in the provinces of Guangdong, Guangxi, Fujian, Hunan and Jiangxi, with the high incidence area concentrated in the Xijiang River basin, which originates in Guangxi and eventually merges into the Pearl River. Information from international tumor registries shows that the incidence of nasopharyngeal carcinoma in China and Southeast Asia did not change significantly in the 50 years before 1980. However, the incidence of nasopharyngeal cancer in Hong Kong, Taiwan, Singapore and the United States in Los Angeles Chinese have shown a downward trend in the past 30 years, with a 30% decline in Hong Kong in the past 20 years (1980-1999). Increased intake of fresh vegetables and decreased consumption of salted fish and tobacco may be partly responsible, as may the increase in non-Cantonese immigrants. Meanwhile, the mortality rate from nasopharyngeal cancer in Hong Kong has declined by 50% due to improved treatment techniques. Three all-cause of death data in China showed a significant decrease in nasopharyngeal carcinoma mortality, and a decreasing trend in incidence and mortality was also observed in low incidence areas such as Wuhan and Shanghai in China, but analysis of incidence rates in high incidence areas of Sihui, Guangdong and Cangwu, Guangxi for 20-25 years (1978/1982-2002) showed a stable incidence rate and a slight decrease in mortality. Data from Zhongshan City, Guangdong, from 1970 to 2007 showed no change in the trend of nasopharyngeal carcinoma incidence, with a WB rate of 27.5/100,000 in men and 11.3/100,000 in women. According to the different differentiation status of its tumor cells, there are three categories of WHO histological classification of nasopharyngeal carcinoma: Class I, differentiated keratinizing squamous carcinoma (25% of North American nasopharyngeal carcinoma; 2% of southern Chinese nasopharyngeal carcinoma); Class II, non-keratinizing carcinoma (12% of North American nasopharyngeal carcinoma; 3% of southern Chinese nasopharyngeal carcinoma); Class III undifferentiated type (63% of North American nasopharyngeal carcinoma; 95% of southern Chinese nasopharyngeal carcinoma). The WHO categories II, III can be attributed to undifferentiated nasopharyngeal carcinoma (UNCT), which develop in association with EBV and have similar treatment response and prognosis. A 38-year trend study in Zhongshan City showed no significant change in the histological type of nasopharyngeal carcinoma. Research and evaluation of screening methods for nasopharyngeal carcinoma The etiology of nasopharyngeal carcinoma is complex and involves multiple factors including genetic susceptibility, EBV infection and exposure to chemical carcinogens In 1976, Henle et al. found VCA-IgA and EA-IgA in patients with nasopharyngeal carcinoma, and in the same year, a Hong Kong study found that VCA/IgA was 93.2% seropositive in patients with nasopharyngeal carcinoma, thus The idea of EBV-specific IgA antibodies for nasopharyngeal cancer diagnosis and screening was proposed. Screening for nasopharyngeal cancer in China began in the late 1970s. Zeng Yi was the first to establish the screening method of serum VCA-IgA detection by immunoenzymatic method, and in 1978, he first started to screen 12,000 people aged 40-59 years in Wuzhou, Guangxi, an area with a high incidence of nasopharyngeal carcinoma, and the result was that the VCA/IgA positive rate was 5.3% (antibody titer ≥1:10), and EA/IgA was detected after VCA/IgA positive, and 13 cases of nasopharyngeal carcinoma were detected in the VCA/IgA positive group. 13 cases of nasopharyngeal carcinoma and 9 cases of NPC were detected in the EA/IgA positive population. 1990, based on the results of a screening study of 98,000 people in Zhongshan, Sihui and Guangzhou, Guangdong, the concept of a high-risk population for nasopharyngeal carcinoma was proposed, with an early diagnosis rate of about 60%. The commonly used immunoenzymatic method for serological screening suffers from variable criteria for VCA/IgA positivity (≥1:5 or ≥1:10), large differences in positivity rates, low positive predictive values (0.11%-0.53%), complex criteria for high-risk populations, and the absence of nationally approved detection reagents and low automation have affected the widespread implementation of this screening method and made it difficult to carry out in areas outside the screening demonstration sites. With advances in immunological techniques, immunoenzymatic assays and other methods are gradually being replaced by ELISA methods for detecting EBV antibodies, which contribute to the automation and standardization of testing. At the same time, research on EBV antibody profiles continues to break through, and more and more EBV antibodies are being applied to clinical screening, with combined screening of more than two antibodies gradually replacing VCA/IgA single antibody testing. Cheng Weimin et al. used ELISA to detect EBNA1/IgA, EBNA1/IgG and Zta/IgG antibody levels in serum for the first time, and the sensitivity and specificity of the combination of the three were 93% and 92% at the highest. Liu Qing and Liu et al. proposed the use of logistic regression to combine the information of the two EBV diagnostic indicators and use predicted probabilities to aid in diagnosis, achieving the effect of simultaneously improving sensitivity and specificity, simplifying the definition of serologically high-risk groups, and screening the optimal combination scheme EBNA1/IgA + VCA/IgA, the sensitivity and specificity of the combined test could reach 95.3% and 94.1 %. Accordingly, this nasopharyngeal cancer screening protocol was adopted in the 2011 version of the Chinese Technical Protocol for Cancer Screening and Early Detection and Treatment. In addition to EB serology, there have been a few studies on plasma EBVDNA for nasopharyngeal cancer screening in recent years. In Hong Kong, 1318 people were analyzed for plasma EBV DNA and followed up, and three cases of nasopharyngeal carcinoma were diagnosed as EBV DNA positive within 2 years, which was considered an effective indicator for early diagnosis of nasopharyngeal carcinoma. The results of a study of 825 people with high risk of EBV serology in Zhongshan and Sihui showed that plasma EBV DNA testing was an effective indicator in early diagnosis, but the rate of missed diagnosis of early nasopharyngeal cancer was about 18%. The EBV DNA study of 289 nasopharyngeal brush samples from Indonesia showed that diagnosing nasopharyngeal cancer and monitoring the disease was superior to plasma EBV DNA and EBV serology. Plasma EBV DNA reagents are more expensive than Elisa tests for EBV antibodies, about three times more expensive, and screening performance is not superior to serologic antibody tests, making them difficult to apply in primary screening in large populations. The current protocol for early diagnosis and treatment of nasopharyngeal carcinoma in China Currently, there is no definitive international screening protocol for nasopharyngeal carcinoma, and screening for nasopharyngeal carcinoma is mainly performed in China. The 2011 version of the protocol: In areas with a high incidence of nasopharyngeal cancer, head and neck testing and EBV shell antigen (EBVCA/IgA) and EBV nuclear antigen antibody (EBNA1/IgA) testing are used as primary screening tools for local residents aged 30-69 years; those with positive EBVCA/IgA and EBNA1/IgA or a family history of nasopharyngeal cancer should be followed up continuously for two years; patients with suspected nasopharyngeal cancer on head and neck examination should be followed up continuously for two years. From 2008 to 2010, 28,000 people in Zhongshan and Sihui, Guangdong, were screened using the new EBV serologic combination protocol, and 41 cases of NPC were detected, with a population detection rate of 0.14%, an early diagnosis rate of 68%, and a missed diagnosis rate of <5%. The detection rate was 0.14%, the early diagnosis rate was 68%, and the missed diagnosis rate was <5%. The current screening protocol for NPC has a 3-year interval, i.e., annual serologic follow-up for the positive population and triennial screening for the negative population. This screening interval is based on an analysis of the previous immunoenzymatic population screening follow-up results, and the performance of the new screening protocol is better than the previous protocol, so the screening interval needs to be reevaluated and the follow-up period extended to arrive at an interval that achieves the best health economic cost effectiveness. The cost of screening for nasopharyngeal cancer screening is about $37 per person, the cost of finding one early case is $36,000, and the early detection case index (EDCI) is 1.71 (compared with the national GDP in 2009). The main reason for the higher cost of nasopharyngeal cancer screening compared with esophageal cancer and liver cancer is the lower incidence of nasopharyngeal cancer. However, WHO criteria regarding cost-effectiveness state that EDCI between 1 and 3 are effective. Therefore, early diagnosis and treatment sites for nasopharyngeal cancer in high incidence areas should be adhered to and the population covered by screening should be gradually expanded for the purpose of controlling nasopharyngeal cancer. The main problem of nasopharyngeal cancer screening is the poor compliance of the screening target population, with the participation rate of the target population below 30%, and the compliance rate of men is even lower. The incidence rate of men is generally two to three times higher than that of women, and the low participation rate of men greatly reduces the effectiveness of screening; the high false positive rate of EBV serological screening and the instability of Elisa reagents also affect the effectiveness of screening. The 5-year survival rate of early-stage nasopharyngeal carcinoma has reached more than 90%, but due to the hidden location of nasopharyngeal carcinoma, early diagnosis is not easy, and the outpatient early diagnosis rate is still less than 20% for many years. Screening for nasopharyngeal cancer can increase the early diagnosis rate to more than 70%, and it is entirely possible to reduce the current mortality rate of nasopharyngeal cancer in China by another 35% by widely implementing screening programs for nasopharyngeal cancer in high incidence areas in the future.