Coexistence of early gastric cancer and benign submucosal lesions mimic invasive cancer: a retrospective multicenter experience

Abstract

Objective: To present a study to identify the characteristics of coexisting early gastric cancer (EGC) and benign submucosal lesions, with the aim of reducing the adverse consequences of overdiagnosis and overtreatment.

Methods: In this retrospective study, we searched the endoscopic databases of three tertiary centers. We screened of patients suspected of early gastric cancer submucosal infiltration by conventional endoscopy and ultimately selected for endoscopic submucosal dissection treatment after endoscopic ultrasonography and magnifying endoscopy with narrow-band imaging examination. Patients with coexisting EGC and benign submucosal lesions in histological sections were included. Clinical data and endoscopic images were reviewed. To evaluate the precision of endoscopists' diagnoses for this type of lesion, eight endoscopists with different experiences were recruited to judge the infiltration depth of these lesions and analyze the accuracy rate.

Results: We screened 520 patients and retrospectively identified 18 EGC patients with an invasive cancer-like morphology. The most common lesion site was the cardia (12/18, 66.67%). The coexisting submucosal lesions could be divided into solid (5/18, 27.78%) and cystic (13/18, 72.22%). The most common type of submucosal lesion was gastritis cystica profunda (12/18, 66.67%), whereas leiomyoma was the predominant submucosal solid lesion (3/18, 16.67%). Ten (55.56%) patients < underwent endoscopic ultrasonography; submucosal lesions were definitively diagnosed in 6 patients (60.00%). The accuracy of judgement of the infiltration depth was significantly lower in cases of coexistence of EGC with benign submucosal lesions (EGC-SML) than in EGC (38.50% versus 65.60%, P = 0.0167). The rate of over-diagnosis was significantly higher within the EGC-SML group compared to the EGC group (59.17% versus 10.83%, P < 0.0001).

Conclusions: We should be aware of the coexistence of EGC and benign submucosal lesions, the most common of which is early cardiac-differentiated cancer with gastritis cystica profunda.

Keywords: Early gastric cancer; Endoscopic ultrasonography; Gastritis cystica profunda; Infiltration depth; Submucosal lesions.

Fig. 1

Flow diagram of the patients included in the study. EGC, early gastric cancer; ESD, endoscopic submucosal dissection

Fig. 2

Case 15: A An elevated lesion measuring approximately 1.5x2.0 cm with a central depression, and a rough, red surface mucosa is seen on the posterior wall of the upper middle part of the gastric body. B Microglandular duct disorder and microvascular dilatation on magnification endoscopy. C The mucosal layer of the lesion is significantly thickened; the submucosal layer is slightly thickened; irregular hypoechoic clusters are visible within; and the intrinsic muscle layer is clear. D High-grade intraepithelial neoplasia of the mucosal layer combined with gastritis cystica profunda below (magnification 40x)

Fig. 3

Case 3: A A 1.5x1.5cm type II-a lesion with mucosal hyperemia and erosion is seen on the less curved side of the cardia on white-light endoscopy. B The opening of the glandular duct can be seen at the edge of the lesion. C Microvascular and microglandular duct disorders seen on magnification endoscopy. D High-grade intraepithelial neoplasia of the mucosal layer and submucosal pyloric gland ectopic (magnification 40x)

Fig. 4

Case 4: A A 1.0x2.0cm elevated lesion on the posterior wall of the cardia with a rough mucosal surface and a slight central depression. B ME-NBI shows an increase in the microvascular diameter and irregular microglandular pattern. C Endoscopic ultrasonography scan showing a 2.0x1.6cm hypoechoic cluster with homogeneous internal echogenicity. D A leiomyoma in the submucosa (magnification 40x). ME-NBI, magnifying endoscopy with narrow-band imaging

Fig. 5

Case 13: A A type IIa+IIc lesion measuring approximately 2.0x3.0 cm is seen in the lower curvature of the gastric body with clear borders. B Magnification endoscopy showing a disorganized surface with a microvascular diameter and microglandular pattern. C A yellow tumor with indistinct borders is seen in the submucosa after dissection. D Low-grade intraepithelial neoplasia in the mucosal layer and submucosal ectopic pancreas (magnification 40x)

Fig. 6

A Accuracy rate in diagnosing the EGC-SML and EGC infiltration depth for each endoscopist. B Comparison of the diagnostic accuracy between the EGC-SML and EGC group, P=0.0167. C Over-diagnosis rate in group EGC-SML and EGC, P<0.0001. EGC-SML, coexistence of early gastric cancer and benign submucosal lesions; EGC, simple early gastric cancer

Fig. 7

Flow diagram for the diagnosis of upper gastrointestinal early cancer with submucosal tumor-like morphology. WLE, white-light endoscopy; ME-NBI, magnifying endoscopy with narrow-band imaging; EUS, endoscopic ultrasonography