Esophageal squamous cell carcinoma (ESCC) has been well characterized as a major histological type in China and occurred predominantly in the mountain rural region with poor economics. Nutritional deficiencies have been recognized as major risk for esophageal carcinogenesis in these rural regions. In the past decades, the rural economic status in China has improved apparently. However, the time trending for ESCC in rural regions has not been characterized. The present study was thus undertaken to determine the time trending for the ratio of rural and urban patients with ESCC in a single institute in northern China over the past 30 years (1985-2014). All the 66,515 ESCC patients in this study were derived from the esophageal and gastric cardia carcinoma databases of 500 thousands patients (1973-2015) established by Henan Key Laboratory for Esophageal Cancer Research of the First Affiliated Hospital of Zhengzhou University in Henan, China. Of the ESCC patients, 50,313 patients had been recorded with detailed address. Based on the diagnosed time, these patients were divided into three groups with periods of 1985-1994, 1995-2004 and 2005-2014. The rural and urban regions were recognized based on the government administrative division of China. The rural region in China refers to the farmer village with hundreds to thousands population. Chi-Square test was used to analyze the different distributions of ESCC patients with a p-value of less than 0.05 as significant. The results demonstrated that more than 84% of the ESCC patients occurred in rural regions with an overall ratio of 5:1 for rural and urban regions (p < 0.0001). Moreover, over the past 30 years with three periods, the ratios for rural and urban regions were 5.4:1, 5.5:1 and 5.4:1, respectively. The present results also demonstrated that over the past 30 years with three periods, ESCC occurred predominantly in males with ratios for male and female as 1.5:1, 1.4:1 and 1.5:1, respectively in rural regions and 1.6:1, 1.6:1 and 1.8:1, respectively in urban regions. Interestingly, the mean age both in male and female in urban regions was slightly older than that in rural regions (urban vs. rural: 60.7±9.86 vs. 59.8±9.38 in male and 62.2±9.57 vs. 60.6±9.47 in female, respectively). The present study demonstrated that ESCC remains the major healthy burden in rural regions in China. Considering the relative low socioeconomic status in China, the prevention and control of ESCC should be enhanced in rural regions in terms of more control programs, medical and education resources. [Supported by National High-Tech Research and Development Program of China (SQ2015AA0202183), Project for Characteristic and Advantage Discipline of Henan Province (20151208)] Note: This abstract was not presented at the meeting. Citation Format: Shou Jia Hu, Hai Jun Yang, Neng Chao Wang, Xiu Min Li, Shuang Lv, Qi De Bao, Wen Bin Yue, Hui Meng, Dan Feng Du, Xue Min Li, Fu You Zhou, Jian Li, Li Dong Wang. Time trending for the ratio of rural and urban patients with esophageal squamous cell carcinoma in a single institute in northern China over the past 30 years [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 264. doi:10.1158/1538-7445.AM2017-264

Esophageal squamous cell carcinoma (ESCC) remains one of the leading cause of cancer-related death in China. Moreover, more than 90% of the ESCC patients have been in the advanced stage when diagnosed, the 5-year survival is very poor even though the medical techniques have been improved in the past decades. Although the accumulated evidences have suggested the crucial role of genetic changes in esophageal carcinogenesis, the target therapy based on these genetic changes is largely in the very beginning, and radical esophagectomy and radiochemotherapy remain the chief choice for ESCC treatment at present. The present study was thus designed to evaluate the efficacy of the present treatment methods in China to provide more information for optimal choice in advanced ESCC treatment. The enrolled 20,712 ESCC patients in this study were from the ESCC database in Henan Key Laboratory for Esophageal Cancer Research of the First Affiliated Hospital, Zhengzhou University. Of the patients, there were 12,818 males with a mean age of 59.59±8.2 and 7,894 females with a mean age of 60.34±8.3. All the 20,712 patients were confirmed by histopathology as ESCC at II to IV stage (advanced stage) and classified into three groups based on the treatment methods: radical esophagectomy (R0) alone (17,577, 84.8%), R0 plus radiochemotherapy (2,510, 12.1%) and radiochemotherapy alone (625, 3.1%). The followed-up was undertaken until 2016. The SPSS21.0 software and Kaplan-Meier survival analysis and Log Rank test were used to evaluate the efficiency of different treatments. The results demonstrated that the overall median survival time for the three groups was 5.81 years, 4.82 years and 2.85 years, respectively (P<0.001). Moreover, compared with surgery alone, R0 plus radiochemotherapy did not prolong survival of the advanced patients. Obviously, much efforts, especially combined with genetic application are much desirable to improve the survival for the advanced ESCC patients. [Supported by National High-Tech Research and Development Program of China (SQ2015AA0202183), Project for Characteristic and Advantage Discipline of Henan Province (20151208) and Correspondence to: Li Dong Wang, Email: ldwang2007@126.com] Note: This abstract was not presented at the meeting. Citation Format: Rang Cheng, Fu You Zhou, Neng Chao Wang, Ran Wang, Wei Peng Wang, Xian Zeng Wang, Wen Bin Yue, Jian Wei Zhou, Zhan Hui Miao, Guang Cheng Ding, De Chao Bu, Li Dong Wang. Impact of the different treatments on the survival of advanced esophageal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3276. doi:10.1158/1538-7445.AM2017-3276