Schwannoma of the stomach: a case report

Common Benign Nerve Sheath Tumor at an Uncommon Location - Gastric Schwannoma

Gastric schwannomas are rare types of gastrointestinal mesenchymal tumours that are slow-growing and mostly benign. They are usually asymptomatic. In some cases, nonspecific gastric symptoms, palpable mass, and bleeding can be seen. A definitive diagnosis requires pathological and immunohistochemical examination, and surgical resection offers an excellent prognosis with uncommon recurrence. We present a case of a 62-year-old woman who underwent exploratory laparotomy and wedge resection with preoperative diagnosis as gastrointestinal stromal tumor and postoperatively diagnosed as schwannoma on histopathology.

Gastric schwannoma: The gastrointestinal tumor simulator - case report and review of the literature

INTRODUCTION AND IMPORTANCE

Gastric schwannoma is a rare and benign tumor originating from the peripheral nerves of the stomach. Despite its benign nature, this tumor typically remains asymptomatic for an extended period, and its radiological and endoscopic presentation poses challenges in distinguishing it from other gastric mesenchymal tumors.

CASE PRESENTATION

Here, we present a rare case of a patient experiencing gastric pain and melena secondary to a gastric mass. The initial preoperative diagnosis indicated a gastrointestinal stromal tumor, but subsequent pathological and immunohistochemical staining of the surgical specimen confirmed the presence of gastric schwannoma.

DISCUSSION

To gain insights into this uncommon condition, we conducted an electronic search on PubMed using the keywords "gastric schwannoma" and "gastric neurinoma." Our focus centered on case series containing more than five cases of gastric localization, resulting in the analysis of 14 case series involving a total of 321 patients. Our review aims to comprehensively discuss the clinical, radiological, and therapeutic aspects associated with this rare disease.

CONCLUSION

In the absence of a definitive preoperative diagnosis, the surgical approach is considered the primary treatment for resectable gastric schwannoma, given its excellent long-term outcomes. However, further studies are imperative to better define the role of endoscopic resection in managing this condition.

Gastric Schwannoma-Two Unusual Cases with Usual Presentation and Review of Literature

Schwannomas, also known as neurilemmomas, are characteristically benign, slow growing neoplasms originating from Schwann cell sheath. Gastrointestinal schwannomas are very rare with stomach being the most affected organ representing approximately 0.2% of all gastric tumours. Malignant transformation is rarely reported in these tumors and complete surgical resection with negative margins is the recommended treatment. Herein, we report our experience of 2 cases of gastric submucosal spindle cell tumour (SMT), which were preoperatively assumed to be as gastrointestinal stromal tumor (GIST), however postoperatively confirmed as schwannoma on immunohistochemical examination.

Incidental finding of a gastric schwannoma: a case report

Gastric schwannomas are rare peripheral nerve sheath tumors which are usually found incidentally while undergoing workup for other conditions. Despite their benign nature, they require surgical resection with negative margins. It is important to differentiate gastric schwannomas from gastrointestinal stromal tumors prior to surgical excision, as this can alter the recommended surgical plan. This can be achieved with endoscopic ultrasound and fine needle aspiration with analysis of the sampled tissue using immunohistochemical stains. We present the case of a 68-year-old female patient with an incidental finding of a gastric fundus schwannoma. Laparoscopic gastric wedge resection was performed with complete excision of the tumor and negative margins. Pathology was confirmed with immunohistochemical stains positive for S-100 and negative for CD117 and DOG1. Post-operative recovery was uneventful without tumor recurrence.

What About Gastric Schwannoma? A Review Article

PURPOSE

Gastric schwannomas (GSs) are rare mesenchymal neoplasms of the gastrointestinal tract. Diagnosis is often achieved postoperatively, based on pathology reports of retrieved specimens. The aim of the present study is to follow up all patients with gastric schwannoma (Gs) undergoing endoscopic, partial, or more extended surgery and to evaluate the appearance of local or distant recurrence.

METHODS

A PubMed, Cochrane, and Embase systematic review of the literature has been performed. Original papers, review articles, and case reports published between 1988 and 2019 were considered eligible. All the studies who met the inclusion criteria were analyzed. Statistical analysis of data has been performed using GraphPad Prism 7 software.

RESULTS

Three hundred twenty-eight articles were found, and a total of 102 were included and analyzed in depth. Fifty-three papers reported the follow-up information, ranging from 1 to 417 months across different studies. Among them, 31 patients underwent endoscopic removal of the gastric lesions; 140 patients underwent local surgery, including wedge resection or partial gastrectomy; and 148 patients underwent subtotal or total gastrectomy. The median follow-up was of 27-38-33 months, respectively. No recurrence or distant metastasis was detected in the endoscopy group. Among local surgery group, liver metastasis was reported in one case; in extended surgery group, one patient died for multiple liver metastases.

CONCLUSIONS

Local or more extended surgery involved a larger cohort of patients and reported satisfactory long-term results compared with endoscopy group. Surgery in absence of a definite preoperative diagnosis is considered the gold standard treatment for resectable Gs.

Clinical Characteristics and Surgical Management of Gastrointestinal Schwannomas

Objectives

Schwannomas are tumors arising from Schwan cells of the neural sheath. Gastrointestinal schwannomas (GS) are rare and easily confused with a heterogeneous group of neuroectodermal or mesenchymal neoplasms. The aim of the present study is to analyze the clinicopathological features, surgical management methods, and long-term prognoses of GS patients.

Methods

Between August 2004 and July 2019, 51 patients with GS were treated at the Peking Union Medical College Hospital. The medical records were reviewed retrospectively. A database containing demographic characteristics, clinical symptoms, imaging tests, operation details, pathological results, and prognoses was constructed and analyzed.

Results

GS accounted for 2.0% of all schwannomas. The cohort comprised 19 men (37.3%) and 32 women (62.7%). The mean age was 55.7 ± 11.4 years. The most common symptom was abdominal pain (29.4%). Twenty-seven patients (52.9%) were asymptomatic and diagnosed incidentally. The most common tumor location of GS was the stomach (90.2%). S-100 had the highest positive rate (100%) in immunohistochemical staining. Forty-six patients (90.2%) were followed-up at a mean period of 49.5 ± 41.4 months. Forty-four patients (95.7%) survived without tumor, 1 patient survived with tumor, and 1 patient died. The 5-year cumulative overall survival rate and cumulative disease-free survival rate were 97.5% and 95.2%, respectively.

Conclusion

GS are rare gastrointestinal tumors with favorable prognoses after surgical resection. Stomach is the most common site. Definitive diagnosis is determined by postoperative pathology. S-100 expression has diagnostic significance.

Endoscopic ultrasound-guided fine-needle aspiration cytology in the diagnosis of the gastrointestinal stromal tumor of the stomach

BACKGROUND

This study aims to evaluate the usefulness of endoscopic ultrasound-guided fine-needle aspiration cytology (EUS-FNAC) in the diagnosis of the gastric gastrointestinal stromal tumor (GIST).

METHODS

We retrospectively investigated the efficacy and accuracy of EUS-FNAC in the diagnosis of gastric GIST. Cytological smears and cytoblock sections including immunohistochemistry and mutational studies from patients diagnosed as gastric GISTs were retrieved.

RESULTS

Thirty patients (mean age 68.8 years, range 32-88 years, Male:Female 1:1.7) were diagnosed by cytological and cytoblock study to have GIST. The size of tumors ranged from 1.6 to 25 cm (mean 6.0 cm). 7 (23%) cases were incidentally discovered. Location was: gastric body 13 (43.3%), fundus 8 (26.7%), antrum 7 (23.3%), cardia 2 (6.7%). The study of removed tumors was correlated with the cytological findings. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 75%, 100%, 100%, 46%, and 96%. There were no false-positive cases. The preoperative risk assessment of 27 cases with cytoblock were: none 3 (11.1%), very low 8 (29.6%), low 12 (44.4%), high 3 (11.1%), insufficient clinical data 1 (3.7%). The follow-up varied from 2 to 120 months (mean 46.7 months). Only 1 patient of the high-risk group died. The most frequent mutations found were those of c-KIT in exon 11.

CONCLUSIONS

Pathological diagnosis was based on a combination of cytological, histopathological, and immunohistochemical features. EUS-FNAC is a reliable, accurate, and safe method for the diagnosis of GIST. The cytoblock allows tumor risk classification and mutational study of the cases.

Clinical characteristics and surgical treatment of schwannomas of the esophagus and stomach: A case series and systematic review

BACKGROUND

Gastrointestinal schwannomas are slow-growing benign mesenchymal neoplasms that originate from Schwann cells of the nerve sheath of Auerbach´s plexus or less frequently from Meissner´s plexus. The main differential diagnosis of gastric schwannomas are the gastrointestinal stromal tumors (GISTs), which are classified by their immunohistochemistry. The treatment of choice for gastric schwannomas is surgery where laparoscopy plays an important role. Wedge resection, subtotal or total gastrectomy can be done. In its counterpart, esophageal schwannomas are benign tumors of the esophagus that are very uncommon since they comprise less than 2% of all esophageal tumors. The main differential diagnosis is the leiomyoma which corresponds to the most common benign esophageal tumor, followed by GIST. The treatment consists on tumoral enucleation or esophagectomy.

AIM

To review the available literature about gastrointestinal schwannomas; especially lesions from de stomach and esophagus, including diagnosis, treatment, and follow up, as well as, reporting our institutional experience.

METHODS

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines. The following databases were used for reviewing process: PubMed, Ovid, MEDLINE, and Scopus. Only English language manuscripts were included. All gastrointestinal schwannomas specifically located in the esophagus and stomach were included. Cases that did not report long-term follow-up were excluded.

RESULTS

Gastric localization showed a higher prevalence in both, the literature review and our institution: 94.95% (n = 317) and 83% (n = 5) respectively. With a follow-up with disease-free survival greater than 36 mo in most cases: 62.01% (n = 80) vs 66.66% (n = 4). In both groups, the median size was > 4.1 cm. Surgical treatment is curative in most cases

CONCLUSION

Schwannoma must be taken into account in the differential diagnosis of gastrointestinal mesenchymal tumors. It has a good prognosis, and most are benign. A disease-free survival of more than 36 mo can be achieved by surgery.

Gastric Schwannoma: A Case Report and Review of the Literature for Gastric Submucosal Masses Distinction

Schwannomas origin from Schwann cells sheath and generally are benign, slow-growing, and asymptomatic neoplasms which frequently appear in the head and neck. Although gastrointestinal schwannoma is really rare, the most affected organ in GI system is the stomach. Gastric schwannoma forms 0.2% of all gastric tumors. This neoplasm is always detected as a submucosal mass, the same as other gastrointestinal stromal tumors. Although these tumors have almost the same presentations, they are completely different at therapeutic options and prognoses. Hence, it is important to distinguish them apart and make an accurate diagnosis to optimize treatment outcomes. Herein, we report a case of 28-year-old woman with frequent vomiting and abdominal pain caused by 5 × 6 cm schwannoma in the antrum of the stomach. This is a rare case of gastric outlet obstruction due to a massive schwannoma. In addition, all other probable submucosal masses will be discussed at different aspects.

Gastric schwannoma-a rare benign mimic of gastrointestinal stromal tumor

Schwannomas most commonly manifest as acoustic neuromas in the vestibulo-cochlear nerve (CN VIII). These may occur unilaterally as primary tumors, or bilaterally secondary to neurofibromatosis type 2. More rarely, they present in extra-cranial sites, including the gastrointestinal tract. Gastrointestinal schwannomas are believed to arise from Auerbach’s plexus in the muscularis propria, and are classified as mesenchymal tumors. Here, we report a rare case of a 49-year-old woman who had surgical resection of a gastric mass which was eventually diagnosed as gastric schwannoma.