GDCs with a pseudostratified columnar ciliated epithelium (also named foregut duplication cysts of the stomach) are supposed to originate from a respiratory diverticulum, arising from the ventral foregut [7
]. This type of gastric duplication is very rare. Including the present report, there have so far been only 21 reported cases. Evaluating patient data, summarized in Table , gastric FDCs seem to be a late-onset disease with no differences in relation to gender. In most cases these lesions are located in the upper part of the stomach: at the level of the cardia, near the gastroesophageal junction, or in the anterior or posterior wall of the fundus. Very often, as in our patient, they are asymptomatic and incidentally found. Symptoms, when present, are not specific, including mainly abdominal or epigastric pain. Consistency of FDCs can range from a thin free-flowing fluid to thick proteinaceous material [8
Gastric duplication cyst lined by pseudostratified columnar ciliated epithelium
Despite advances in imaging, cysts that contain solid secretions can often be misclassified as soft tissue masses. A rate of computed tomography misdiagnosis ranging from 43 to 70% of cases has been reported [9
]. Magnetic resonance imaging does not seem to significantly improve diagnostic accuracy [6
]. Therefore, in the majority of the reported cases, a definite diagnosis was made only during surgical resection or by pathological examination on surgical specimens [11
]. EUS is currently the best available method for the diagnosis of the subepithelial lesions of the gastrointestinal tract. This technique has also been proved to be superior to computed tomography scan in distinguishing cystic from solid masses [1
], but the diagnostic accuracy of EUS is affected by the variation of intracystic contents. The use of contrast-enhanced EUS may also be very useful in the differential diagnosis of digestive diseases [15
]. However, we did not find in the literature any paper discussing the role of contrast-enhanced EUS in the diagnostic evaluation of GDCs.
On the basis of EUS morphologic findings alone, a GDC may be misdiagnosed as a GIST, which is the most common gastric subepithelial lesion, as in the case reported by Jiang and colleagues [17
]. In the present case, EUS findings also suggested a diagnosis of GIST. Since the surgical treatment of GISTs involving the upper part of the gastric wall may require an extended gastric resection, we performed EUS-guided FNAC in order to confirm the diagnosis. While inserting the needle we realized that the presumed GIST was a cystic lesion, and the cytological sampling led to a diagnosis of GDC with respiratory epithelium. There are only few case reports concerning EUS-guided FNAC of gastrointestinal duplication cysts [1
], but since respiratory-type cells or detached ciliary tufts are visualized in cytologic preparations, a definite diagnosis can be easily made [10
]. Pitfalls can occur if the cyst is lined by gastric epithelium only, as in the case described by Wang and colleagues [1
]. EUS-guided FNAC led to a cytological misdiagnosis of gastric mucinous neoplasm.
Owing to the report of gastric cancer arising in gastric duplication [2
], surgery is nowadays considered the standard treatment for these lesions [24
]. The possibility of a malignant transformation is related to the presence of a gastric-type lining epithelium. Ponder and Collins therefore suggested that surgery is not necessary if respiratory epithelium is recognized on EUS-guided FNAC [20
]. Nevertheless, it has been shown in the FDCs of the stomach that pseudostratified columnar ciliated epithelium may be associated with gastric epithelium [24
], which could be missed by cytological sampling. For this reason, it may be that a complete surgical excision of the cyst should be recommended; also, in selected cases, some authors consider its observation as a reasonable option. A surgical procedure that does not require a gastric resection can be easily undertaken by a laparoscopic approach, as performed in this case.