Esophageal submucosal gland duct adenoma (ESGDA) is a rare, benign tumor with non-specific clinical features and imaging findings, often leading to misdiagnosis.

In this report we describe the clinicopathological features of a new-onset case of ESGDA and review 19 previously-reported ESGDA cases in the literature.

The median age of the 20 patients was 70 years, and the male-to-female ratio was 5:2. Lesions located in the lower esophagus accounted for 81% of the cases. Chest and abdominal discomfort were the main clinical symptoms, and endoscopic findings mostly included polypoid masses that were impossible to correctly diagnose prior to excision and biopsy. On microscopic examination, the submucosal tumor was found to be composed of glandular cavities of various sizes, bland cytology with infrequent mitotic figures, and the interstitium was infiltrated by a large number of lymphocytes. Immunohistochemical analysis revealed the expression of adenomyoepithelial cytokeratins (CK) CK7, CK5/6, and p63. Local tumor resection was performed, the longest follow-up period was 132 months of the 20 patients, the prognosis was favorable, and no recurrence or metastasis.

ESGDA is more common in the lower esophagus in elderly patients, and its clinical symptoms are atypical. Taking into account its characteristic microscopic morphology and immunohistochemical markers, the possibility of this rare disease should be considered to avoid misdiagnosis or missed diagnosis. Complete en bloc resection with Endoscopicp may be the best strategy for both the diagnosis and treatment of this entity.

This article reports a rare case of esophageal submucosal gland duct adenoma (ESGDA). The patient was found to have this tumor after undergoing endoscopy in an outpatient clinic due to occasional tingling while eating. White light endoscopy revealed the tumor as a dumbbell-shaped bulge, and ultrasound endoscopy revealed it as a hypoechoic mass located in the submucosal layer. The tumor was successfully resected by endoscopic mucosal dissection with no postoperative recurrence and a good prognosis. In conjunction with literature analysis, the diagnosis of ESGDA relies mainly on endoscopic and pathologic examinations, and its histologic features are highly specific. Despite the rarity of ESGDA, accurate histologic evaluation is essential to avoid misdiagnosis. Complete endoscopic resection is an effective treatment with a favorable long-term prognosis. Further studies remain necessary to reveal its pathogenesis.

Submucosal glands (SMGs) present throughout human esophagus with clusters at either the upper third or lower third of the organ. SMGs tend to atrophy with age, and neoplasms arising in these glands are rare. In order to bring convenience to diagnosis, we summarize the histopathologic characteristics of all esophageal submucosal gland tumors (SGTs). Due to the morphological similarity, the nomenclature of salivary tumors is adopted for SGTs. However, there is great confusion about the definition and histogenesis of these tumors, especially the malignant subtypes. In the literature, esophageal mucoepidermoid carcinoma and adenoid cystic carcinoma usually adjoin the surface squamous epithelium and coexist with intraepithelial neoplasia or invasive squamous cell carcinoma (SCC). In addition, the typical gene alterations of salivary tumors have not been reported in these SGTs. Therefore, we propose to apply stringent diagnostic criteria to esophageal SGTs so as to exclude mimickers that are SCCs with various degree of SMG differentiation.

Esophageal submucosal gland duct adenoma (ESGDA) is a rare tumor. The clinicopathological features of the ESGDA and its precursor lesion have not been comprehensively evaluated. In this study, we aimed at delineating the clinicopathological features of the ESGDA and cyst formation of the esophageal submucosal gland duct (ESGD), as well as their correlations and clinical implications. We identified three cases of ESGDA and 16 cases of cyst formation of the ESGD among 786 endoscopic mucosal resection specimens over a 7-year period. The median patient age was 58 years with a male predominance. These lesions were small submucosal bulges locating at the lower esophagus with a size no more than 1 cm. The main microscopic changes of these lesions included content retention, multilayered epithelium or papillary folds of the ESGD and inflammatory cell infiltration, acidophilic degeneration, hyperplasia or atrophy of the acini. The included cases generally showed moderate to severe microscopic esophagitis. The ESGDA was mainly consisted by multiple glandular cysts covered by two layers of cells. Immunohistochemical results showed that the luminal duct lining cells and basal cells were positive for CK7 and p63, respectively. Both of the two layer cells were positive for HMWCK and negative for CK20, p53, CDX2, MUC5AC, MUC6, MUC2 and MUC1. The proliferation index was very low (1%). The diagnostic criteria of the ESGDA were proposed and, the differential diagnosis was discussed. Cyst formation of the ESGD is considered to be the precursor lesion of the ESGDA, because they have overlapping clinicopathological features with progressive relationship. In addition, the ESGDA have close connection with advance of the GERD and, probably, an increased risk of carcinoma.

Esophageal gland duct adenomas are extremely rare tumors. Here, we report the case of a 75-year-old Japanese man who had undergone total gastrectomy for advanced gastric cancer. Esophageal gland duct adenoma was incidentally found in the lower esophagus. It appeared to be detached from the site of gastric cancer and was well demarcated without a capsule. Histologic analysis revealed papillary and cystic structures mainly comprising eosinophilic cells with minimum nuclear atypia. Immunohistochemical analysis revealed that the tumor were diffusely positive for the S100 protein with preserved alpha-SMA-positive myoepithelial cell layers and a characteristic cytokeratin expression pattern similar to that in normal esophageal gland ducts (CK5/6+++, CK7+++, CK17+, CK18+, CK19+++, CK20-, HMWCK+++). In addition, differentiation into the terminal duct was confirmed by a combination of mucin staining and immunohistochemical and ultrastructural examinations. This is the first report that refers to the ultrastructural findings of an esophageal gland duct adenoma and describes terminal duct differentiation. We believe that the possibility of an esophageal gland duct adenoma should be considered when diagnosing a ductal or glandular lesion of the esophagus.