It has been well recognized that esophageal squamous cell carcinoma (ESCC) is the major histopathological type of esophageal cancer in China. However, it is not even clear how many histopathological types of esophageal malignant tumor (EMT) exist and if the histopathological patterns have changed over the past decades in China. The present study was thus undertaken to characterize the histopathological patterns over 40 years at a single institute in northern China, the high incidence area for esophageal cancer. All the patient information was from esophageal cancer database in Henan Key Laboratory for Esophageal Cancer Research of the First Affiliated Hospital, Zhengzhou University in Henan, China (1973-2015). A total of 66,216 patients with MET and detailed histopathological records were enrolled in this study, including 39,873 males with a mean age of 60±6 and 26,343 females with a mean age of 60±6 from 1975-2014. All the patients were classified into four period groups based on the diagnosed time, group I (1975-1984, 4,331/6.5 %), group II (1985-1994, 14,577/22%), group III (1995-2004, 20,781/31.4%) and group IV (2005-2014, 26,527/40.1%). The results demonstrated 12 different histopathological types of EMT. The most common type was ESCC (64,800, 97.4%), followed by esophageal adenocarcinoma (EAC, 1268, 1.9%), esophageal small cell carcinoma (201, 0.3%), esophageal adenosquamous carcinomas (EASC, 119, 0.18 %), esophageal spindle cell carcinoma (76, 0.11%), esophageal undifferentiated carcinoma (37, 0.06%), esophageal malignant melanoma (5, 0.008%), esophageal stromal tumor (3, 0.005%), esophageal clear cell carcinoma (2, 0.003%), esophageal malignant schwannoma (1, 0.002%), esophageal lymphatic tumor (1, 0.002%) and esophageal smooth muscle cell sarcoma (1, 0.002%). Time trending analysis showed that, over the past 40 years, ESCC was relatively stable (98.9%, 98.0%, 97.0%, 97.1%, respectively). However, EAC (0.97%, 1.66%, 2.30%, 1.87%, respectively), small cell carcinoma (0.02%, 0.17%, 0.28%, 0.43%, respectively) and spindle cell carcinoma (0.02%, 0.01%, 0.10%, 0.22%, respectively) increased apparently. The present study indicates that ESCC remains the major histopathological type for Chinese esophageal cancer. Interestingly, esophageal adenocarcinoma, small cell carcinoma and spindle cell carcinoma seem to increasing over the past decades. The improved molecular diagnostic biomarkers and the changes of lifestyle including the diet patterns resulted from recent economic development in China, may contribute to the changes of esophageal histopathological types. [Supported by Joint Funds of the National Nature Science Foundation of Chian (U1301227), National Nature Science Foundation of China (81472323), and Correspondence to: Li Dong Wang, Email: [email protected]]

Note: This abstract was not presented at the meeting.

Citation Format: Xue Ke Zhao, Hai Jun Yang, Zong Min Fan, Ji Lin Li, Li Min He, Yun Zhou, Liu Qin Yang, Ying Fa Zhou, Sa Tang, Yang Yang, Lei Ma, Wei Li Han, Li Dong Wang. The changes of esophageal malignant tumors by histopathology over 40 years (1975-2014) at a single institute in northern China [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 258. doi:10.1158/1538-7445.AM2017-258