Advanced gastric adenocarcinoma mimicking a submucosal tumor

Case Report: Clinicopathological characteristics of patients with gastric cancer with features of a submucosal tumour

Purpose

To investigate the clinicopathological characteristics, diagnosis and key points in the differential diagnosis of patients with gastric cancer (GC) with features of a submucosal tumour (GCSMT).

Methods

The clinical presentation and imaging findings of four GCSMT cases diagnosed at our centre from 2016 to 2021 were observed and their clinicopathological outcomes were analysed. The related literature was reviewed. Based on our collected data and the related literature, a total of 31 cases of GCSMT can be summarized.

Results

22 out of 31 cases did not present obvious symptoms and were accidentally discovered during gastroscopic examination. Only 10 patients experienced symptoms such as gastric discomfort, upper abdominal swelling and pain, haematemesis, or haematochezia. The male to female ratio was 22:9 and the age of onset ranged from 40 to 81 years (median age: 63 years). Tumours were located in the upper and middle third of the stomach (24/31), and in the lower third(7/31). The tumour diameter ranged from 0.6 to 7.3 cm, with an average value of 2.5 cm. Endoscopically, the disease manifested as SMTs, with the gastric mucosal surface appearing normal. Most patients underwent radical gastrectomy for GC (80.6%, 25/31). The pathological diagnoses of the 31 cases of GCSMT included well- and moderately-differentiated adenocarcinoma (6/31), poorly differentiated adenocarcinoma or signet ring cell carcinoma 6/31), mucinous adenocarcinoma (9/31), lymphoepithelioma-like carcinoma (7/31), gastric adenocarcinoma of the fundic gland type (3/31). Stage T1b and T2 tumours accounted for 56.7% (17/30) and 26.7% (8/30) of all cases. Lymph node metastases were found in six cases (20.0%, 6/30), whereas distant metastasis was not observed in any of the cases. For the 16 patients whose follow-up data were available, the follow-up time was 5-66 months, during which recurrence or metastasis was not observed.

Conclusion

GCSMT is a rare disease that is often difficult to accurately diagnose through endoscopic biopsy. The importance of gaining an understanding of this disease lies in differentiating it from other SMTs (mostly mesenchymal tumours) to avoid misdiagnosis and missed diagnosis and enable the early diagnosis and treatment of patients.

Early gastric cancer presenting as a typical submucosal tumor cured by endoscopic submucosal dissection: A case report

BACKGROUND

Submucosal tumor (SMT)-like gastric cancer is rare, and almost all cases undergo curative surgical treatment because the submucosal layer is usually deeply invaded by tumor cells or because histopathologic types of SMT-like gastric cancer are undifferentiated or poorly differentiated. No report has been issued on an SMT-like gastric cancer cured by endoscopic resection alone or on changes in the endoscopic features of this type of tumor over several years.

CASE SUMMARY

We describe an exceptional case of a 53-year-old male with a 1.5 cm-sized SMT-like lesion covered by normal-appearing mucosa discovered by esophagogastroduodenoscopy (EGD) at the gastric antrum. Endoscopic ultrasound (EUS) visualized a homogeneous, well-circumscribed hypoechogenic lesion arising from the second sonographic layer with associated subtle obliteration of the third sonographic layer. Initial endoscopic biopsy was negative for neoplasm. The patient refused to undergo an invasive procedure and was subsequently lost to follow-up. Three years after initial detection, EGD revealed the lesion had become markedly erythematous, and at 4 years after initial EGD it had increased in size to 1.8 cm and developed a central ulcer and a heterogeneous EUS echo. Finally, endoscopic submucosal dissection (ESD) was performed, and histopathologic examination revealed a moderately differentiated adenocarcinoma had minutely invaded the submucosal layer (invasion depth 169 μm) but without lymphovascular invasion and with negative resection margins. Fortunately, no additional surgical treatment was required. He has been followed for 4 years after ESD without any evidence of local or distant recurrence.

CONCLUSION

This report describes an extremely rare case of early gastric cancer presenting as SMT that was cured by ESD after a treatment delay of 4 years and the endoscopic changes that occurred during this period. The report highlights the importance of considering the possibility of gastric cancer when SMT is encountered in clinical practice.

Advanced gastric cancer with features of a submucosal tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration and boring biopsy preoperatively: A case report and literature review

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Gastric carcinoma with features of a submucosal tumor is a rare condition.

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Gastric carcinoma with features of a submucosal tumor has unique features.

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Tissue sampling must be performed if gastric malignant submucosal tumor is suspected.

Introduction

Gastric cancer with features of a submucosal tumor (GCSMT) is rare, and the preoperative diagnosis is very difficult. We present a case of GCSMT diagnosed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and boring biopsy (deeper biopsy), successfully treated with distal gastrectomy and lymph node dissection.

Presentation of case

An 81-year-old man with a history of myocardial infarction and type 2 diabetes mellitus was admitted to our hospital for further examination of a gastric submucosal tumor. Endoscopic examination of the gastrointestinal tract showed a 30-mm submucosal tumor at the lower gastric body. Enhanced computed tomography revealed a tumor located at the lower body of the stomach and pyloric lymph node swelling. EUS-FNA and boring biopsy from the tumor revealed adenocarcinoma. Accordingly, distal gastrectomy with lymph node dissection was performed. Histopathological examination showed a poorly differentiated adenocarcinoma. Postoperative diagnosis was GCSMT with lymph node metastasis (T2, N1, M0, stage IIA).

Conclusion

We report a rare case of GCSMT with lymph node metastasis. Preoperative diagnosis of GCSMT is necessary to guide surgical management. EUS-FNA and boring biopsy could aid in obtaining adequate quantities of the specimens for histopathological and immunohistochemical diagnosis.

Two cases of mucinous adenocarcinoma of the stomach mistaken as submucosal tumor

A gastric carcinoma with the endoscopic features resembling submucosal tumor (SMT) is rare, and reportedly account for only 0.1% to 0.63% of all resected gastric carcinomas. The preoperative diagnosis of SMT-like gastric carcinoma is challenging, and thus, diagnosis is usually made intraoperatively or postoperatively. Furthermore, mucinous adenocarcinoma is an uncommon histologic subtype of gastric carcinoma characterized as an elevated lesion resembling SMT due to abundant mucin pools in submucosa. Here, we report two cases in which a gastric mucinous adenocarcinoma was mistaken as a SMT.