Long-Term Follow-Up of a Community Assignment, One-Time Endoscopic Screening Study of Esophageal Cancer in China.

PURPOSE: There are no global screening recommendations for esophageal squamous cell carcinoma (ESCC). Endoscopic screening has been investigated in areas of high incidence in China since the 1970s. This study aimed to evaluate whether an endoscopic screening and intervention program could reduce mortality caused by ESCC. METHODS: Residents age 40 to 69 years were recruited from communities with high rates of ESCC. Fourteen villages were selected as the intervention communities. Ten villages not geographically adjacent to intervention villages were selected for comparison. Participants in the intervention group were screened once by endoscopy with Lugol's iodine staining, and those with dysplasia or occult cancer were treated. All intervention participants and a sample consisting of one tenth of the control group completed questionnaires. We compared cumulative ESCC incidence and mortality between the two groups. RESULTS: Three thousand three hundred nineteen volunteers (48.62%) from an eligible population of 6,827 were screened in the intervention group. Seven hundred ninety-seven volunteers from an eligible population of 6,200 in the control group were interviewed. Six hundred fifty-two incident and 542 fatal ESCCs were identified during the 10-year follow-up. A reduction in cumulative mortality in the intervention group versus the control group was apparent (3.35% v 5.05%, respectively; P < .001). Furthermore, the intervention group had a significantly lower cumulative incidence of ESCC versus the control group (4.17% v 5.92%, respectively; P < .001). CONCLUSION: We showed that endoscopic screening and intervention significantly reduced mortality caused by esophageal cancer. Detection and treatment of preneoplastic lesions also led to a reduction in the incidence of this highly fatal cancer.

Environmental exposure and p53 mutations in esophageal cancer patients in areas of low and high incidence of esophageal cancer in China.

Esophageal cancer is the 6th most common cancer in the world, and genetic factors (p53 mutations) in addition to the environmental factors (food, nutrition, smoking, drinking, etc.) are involved in its development. In this study, the association between the both factors, environmental risk factors for esophageal cancer and p53 mutations, in tumor tissues was investigated in 77 patients living in a high-incidence area and 50 patients living in a low-incidence area in Hebei Province, China. Among these patients, p53 mutations were observed in about 50%, without regional differences in the respective frequencies. G:C>A:T (G to A or C to T) transition mutations were the major type of mutations observed in patients in the high-incidence area (19 patients, 50%), whereas G:C>A:T transitions and insertions were observed with equal frequency (8 patients, 33.3%) in the low-incidence area. As for the association with environmental factors, p53 mutations occurred with higher frequency in patients with a daily intake of spicy foods and in those who used unboiled well water in the low-incidence area. Logistic regression analysis showed no association between food intakes and p53 mutations in high- and low-incidence areas. Thus, higher frequency of spicy food intake and use of unboiled well water may be risk factors of esophageal cancer via p53 mutations in China.

Age scope of high-risk population for esophageal cancer in Ci county.

AIM: To define the age scope of high-risk population for esophageal cancer (EC) in Ci county. METHODS: The results of endoscopic examination of 2 013 subjects, cytological screening of 16 763 persons and records of 9 265 patients with EC were analyzed by Ridit methods, the standard age group was 45-49 year group. RESULTS: The average age of patients with moderate esophageal epithelium dysplasia by endoscopic examination was 53.5 years, of severe esophageal epithelium dysplasia, 51.4 years, early EC, 55.6 years. The average age of stage one severe epithelium dysplasia (SEEDI) by cytological screening was 51.2 years, of stage two severe epithelium esophageal dysplasia (SEED II) 51.6 years, of advanced EC 61.7 years. In the group of 40-year olds, the value of Ridit by pathological diagnosis was 0.46, 95% CI, 0.45-0.47, that by cytological diagnosis was 0.45, 95% CI, 0.43-0.47. As the age increased at five-year intervals, the value of Ridit increased significantly. CONCLUSION: In Ci county of a high incidence area of EC, the age definition of high-risk population should be above 45 years.

DHPLC is superior to SSCP in screening p53 mutations in esophageal cancer tissues.

Mutations of the p53 tumor-suppressor gene universally occur on exons 5-8 in human cancer. We analyzed these mutations in esophageal cancer tissue from 207 patients in China using 2 methods, single-strand conformation polymorphism (SSCP), one of the most frequently used methods, and the recently developed denaturing high-performance liquid chromatography (DHPLC), and compared their sensitivity and efficiency. Exons 5-8 of p53 were amplified from esophageal cancer tissue genomes, screened for fragments of mutations and polymorphisms by SSCP and DHPLC in a blind study and confirmed by direct sequencing to detect the mutations and polymorphisms. The numbers detected by DHPLC were greater than those detected by SSCP, though the rate of mutations and polymorphisms was lower in SSCP than in DHPLC, which appeared to detect smaller mutations (substitutions and 1 bp insertions/deletions). Of the mutations with substitutions detected by DHPLC but not by SSCP, 50% substituted adenosine for other nucleotides, suggesting that these mutations are often missed when SSCP is used. According to these data, the sensitivity of SSCP and DHPLC was 81% and 97%, respectively, and the specificity was 97% and 85%, respectively. Our results suggest that DHPLC may be recommended over SSCP when screening gene mutations. Thus, rates of p53 mutations and polymorphisms in esophageal cancer tissue in Chinese patients were 49% and 41% by DHPLC and SSCP, respectively.

Endoscopic survey of esophageal cancer in a high-risk area of China.

AIM: To characterize the histological types of esophageal and cardiac mucosa by endoscopic survey of a population in a high-risk area of esophageal cancer of China. METHODS: A selected cohort of residents in Cixian County during December 2001 and May 2002 was surveyed by using Lugol's staining, followed by computer-based statistical analysis of the data with SPSS 10.0 software. RESULTS: Histologically, the detection rates of squamous epithelial acanthosis, squamous epithelial atrophy, and basal cell hyperplasia in the esophagus were 1.9% (38/2,013), 0.1% (3/2,013) and 0.9% (18/2,013) respectively, and those of mild, moderate, and severe esophagitis were 34.9% (703/2,013), 1.6% (33/2,013) and 0.2% (2/2,013) respectively. Mild, moderate, and severe esophageal dysplasia were detected in 8.6% (172/2,013), 7.8% (157/2,013) and 2.6% (53/2,013) respectively in the selected population, whereas in situ carcinoma, intramucosal carcinoma, invasive squamous carcinoma of the esophagus in 2.5% (50/2,013), 0.2% (4/2,013) and 0.7% (14/2,013) respectively. The detection rates of non-atrophic gastritis and atrophic gastritis of the cardia were 36.3% (730/2,013) and 11.5% (232/2,013) respectively, with mild and severe dysplasia of the cardia detected in 2.5% (51/2,013) and 0.8% (17/2,013), respectively, in this population; the rates of intramucosal adenocarcinoma and invasive adenocarcinoma of the cardia were 0.1% (3/2,013) and 0.8% (17/2,013) respectively. The detection rate of esophageal cancer at early stage was 79.4% (54/68). The survey rate (ratio of examined population to expected population) was 73.8% (2,013/2,725). CONCLUSION: Histologic types of the esophageal and cardiac mucosa were characterized by endoscopic survey in a high-risk population of esophageal cancer, which may help the early detection and treatment of esophageal and cardiac cancers and dysplasia, and reduce the mortality of such malignancies.

An analysis of esophageal cancer incidence in Cixian county from 1974 to 1996.

AIM: To describe the incidence of esophageal cancer (EC) in Cixian, a county of Hebei province during 1974-1996. We analyzed the sex and age characteristics as well as the geographic distribution of EC, in order to determine the impact so that methods of preventing and controlling EC in Cixian can be put in place. METHODS: Since the early 1970s, the cancer registry system has been established, which collects the cancer incidence in Cixian county. The malignant tumors were coded according to International Classification of Disease IX (ICD-9). All the data were checked and analyzed using EPIINFO. RESULTS: The trend of the incidence rate of EC from 1974 to 1996 had declined, (229.9/100 000 vs 178.5/100 000, Odds ratio=1.47, 95 % CI:1.32-1.63, chi(2)=52.89. trend chi(2)=26.54, P<0.001). The incidence rate of males declined significantly (281.81/100 000 vs 157.96/100 000, Odds ratio=1.61, 95 % CI: 1.41-1.84, chi(2)=47.85. Trend chi(2)=44.86, P<0.001), whereas, the females remained steady (157.96/100 000 vs 133.41/100 000, odds ratio=1.28, 95 % CI:1.17-1.49, chi(2)=9.26. trend chi(2)=2.69, P>0.05). Male average annual incidence rate was 142.80/100 000 and the female's was 95.18/100 000. The sex ratio (males to females) was 1.50:1. The incidence rate was increasing along with the age. As to the geographic distribution, the incidence rate in mountainous areas and hilly areas showed a significantly declining trend (mountainous areas, trend chi(2)=149.93, P<0.001; hilly areas, trend chi(2)=42.70, P<0.001). The incidence rate of EC in plain areas had increased (trend chi(2)=22.39, P<0.001). CONCLUSION: The incidence rate of EC in Cixian county shows a trend and has declined after two decades, especially in mountainous area. But compared to other regions in the world, Cixian county still had a high incidence rate of EC.