Diagnostic performance of endoscopy for subsquamous extension of superficial adenocarcinoma of the esophagogastric junction

Abstract

Objectives

Extension of adenocarcinoma of the esophagogastric junction under the squamous epithelium may lead to errors when determining lateral margins. However, the characteristics of subsquamous extension are unclear. Herein, we evaluated the prevalence and characteristics of subsquamous extension of adenocarcinoma of the esophagogastric junction and the diagnostic performance of endoscopy for this condition.

Methods

Eighty-nine consecutive patients with superficial adenocarcinoma of the esophagogastric junction who underwent endoscopic or surgical resection at a tertiary cancer center between January 2010 and December 2017 were retrospectively evaluated. Endoscopic subsquamous extension was defined as a submucosal tumor-like elevation covered by squamous epithelium and/or a brownish area with abnormal microvessels on the squamous epithelium observed using narrow-band imaging. The diagnostic performance of endoscopy for subsquamous extension was evaluated using histological subsquamous extension as gold standard.

Results

Thirty-nine patients (44%) had histological subsquamous extension. Proton pump inhibitor use was significantly associated with histological subsquamous extension [odds ratio: 4.65; 95% confidence interval (CI): 1.77–12.2]. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of endoscopic subsquamous extension were 56% (95% CI: 40–72%), 96% (86–99%), 92% (73–99%), 74% (62–84%) and 79% (69–87%), respectively. The median length difference between histological and endoscopic subsquamous extension was 2 mm (range: −6 to 9 mm).

Conclusions

The sensitivity of endoscopic diagnosis of subsquamous extension was unsatisfactory. The endoscopic length of subsquamous extension tended to be underestimated. An oral safety margin of one centimeter is reasonable during endoscopic resection of adenocarcinoma of the esophagogastric junction.

IMPACT STATEMENT

•  This study will contribute significantly to the literature because this is the first study to determine the difference between the lengths of subsquamous extension detected endoscopically and histologically. This study determines the prevalence of subsquamous extension and identifies characteristics associated with subsquamous extension. An understanding of the risk of subsquamous extension is important when choosing a treatment strategy and planning the resection margins in patients with adenocarcinoma of the esophagogastric junction. This study provides patients with subsquamous extension characteristics and suggests a method for accurately diagnosing this condition.

Keywords:

• Diagnostic techniques and procedures
• esophageal neoplasms
• esophagogastric junction
• narrow band imaging
• sensitivity and specificity

Acknowledgement

We thank all members of the Department of Pathology at Shizuoka Cancer Center for assisting with the pathologic diagnoses.

Ethics statement

The retrospective protocol was approved by the ethical committee of the Shizuoka Cancer Center, Shizuoka, Japan (approval no: J2019-161). All procedures were conducted according to the ethical standards of the responsible committee on human experimentation (institutional and national) and the Helsinki Declaration of 1964 and later versions.

Patient consent

The requirement of informed consent was waived, and the opt-out method was used on the institution’s website.

Author contributions

Kazunori Takada and Yohei Yabuuchi conceived and designed the study. Kazunori Takada and Yohei Yabuuchi analyzed and interpreted the data with support from Yoichi Yamamoto, Masao Yoshida, Noboru Kawata, Kohei Takizawa and Hiroyuki Ono. Tatsunori Minamide, Yuki Maeda, Yoshihiro Kishida, Kenichiro Imai, Kinichi Hotta, Hirotoshi Ishiwatari, Hiroyuki Matsubayashi and Hiroyuki Ono critically revised the manuscript for important intellectual content. All authors approved the final version of the manuscript.

Disclosure statement

Kenichiro Imai and Hiroyuki Ono report personal fees from Olympus. Other authors declare no conflicts of interest for this article.

Data availability statement

All data generated or analyzed during this study are included in this article. Further enquiries can be directed to the corresponding author.

Additional information

Funding

None.