Training in early gastric cancer diagnosis improves the detection rate of early gastric cancer: an observational study in China

Abstract

Few studies have analyzed the training of endoscopists in the diagnosis of early gastric cancer (EGC). This study assessed whether specific training of endoscopists improves the detection rate of EGC. The rates of detection of EGC by endoscopists at the Digestive Endoscopy Center of the Affiliated Nanfang Hospital of China Southern Medical University between January 2013 and May 2014 were retrospectively analyzed. Because some endoscopists received training in the diagnosis of EGC, beginning in September 2013, the study was divided into 3 time periods: January to September 2013 (period 1), September 2013 to January 2014 (period 2), and January to May 2014 (period 3). The rates of EGC detection during these 3 periods were analyzed. From January 2013 to May 2014, a total of 25,314 gastroscopy examinations were performed at our center, with 48 of these examinations (0.2%) detecting EGCs, accounting for 12.1% (48/396) of the total number of gastric cancers detected. The EGC detection rates by trained endoscopists during periods 1, 2, and 3 were 0.3%, 0.6%, and 1.5%, respectively, accounting for 22.0%, 39.0%, and 60.0%, respectively, of the gastric cancers detected during these time periods. In comparison, the EGC detection rates by untrained endoscopists during periods 1, 2, and 3 were 0.05%, 0.08%, and 0.10%, respectively, accounting for 3.1%, 6.0%, and 5.7%, respectively, of the gastric cancers detected during these times. After training, the detection rate by some trained endoscopists markedly increased from 0.2% during period 1 to 2.3% during period 3. Further, the use of magnifying endoscopy with narrow-band imaging (M-NBI) (odds ratio = 3.1, 95% confidence interval 2.4-4.1, P < 0.001) contributed to the diagnosis of EGC. In conclusion, specific training could improve the endoscopic detection rate of EGC. M-NBI contributed to the diagnosis of EGC.

Figure 1

Rates of detection of EGC by W.G. and Q.Z. before and after training on early gastric cancer diagnosis. EGC = early gastric cancer, HGN = high-grade neoplasia, LGN = low-grade neoplasia.

Figure 2

Flow chart of 1927 gastroscopies performed by W.G. and Q.Z. “VS feature” = an irregular microvascular and/or microsurface pattern together with a clear demarcation line, LGN = low-grade neoplasia, HGN = high-grade neoplasia, ESD = endoscopic submucosal dissection, M-NBI = magnifying endoscopy with narrow-band imaging.

Figure 3

EGC lesions detected after training; the M-NBI images and pathological results are shown in a supplemental data file (http://links.lww.com/MD/A149). Under white-light gastroscopy, these EGCs exhibited different morphologic characteristics. EGC = early gastric cancer, M-NBI = magnifying endoscopy with narrow-band imaging.

Figure 4

Examples of EGC categorized as types 0–IIc (A), 0–IIb (B), 0–IIa (C), and 0–IIc (D), respectively. They all had typical VS features of EGC. All of these lesions were diagnosed as high-grade neoplasias. EGC = early gastric cancer.