Selected unusual tumors of the stomach: a review

Endoscopic submucosal excavation for gastric plexiform fibromyxoma: A case report and systematic review of literature

Plexiform fibromyxoma (PF) is a rare mesenchymal tumor of which the pathogenesis and molecular changes are still unclear. Histologically, it is characterized by a cluster of bland spindle or ovoid cells growing in the mucoid or fibromyxoid stroma rich in small blood vessels. At present, surgical resection is the primary treatment for PF.

Imaging findings of gastrointestinal tract tumors in children and adolescents

Gastrointestinal (GI) tract tumors are rarely seen in children and adolescents, and can easily be misdiagnosed. Lymphoma is the most frequent GI tract tumor, and the common locations are ileum and ileocecal area. GI tract tumors may present as large heterogeneous mass lesions. For gastric and colonic tumors, increased wall thickening usually prompts the diagnosis of GI tract tumors. Computed tomography and magnetic resonance imaging might be used in clinically suspected cases for correct/appropriate diagnosis and management. Awareness as regards the most common tumors and their locations is paramount for radiologists. Likewise, the aim of this article was to define the imaging findings of primary benign and malignant GI tract tumors in children and adolescents.

Gastric schwannoma: report of two cases and review of the literature

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Schwannomas are mesenchymal tumors.

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Schwannomas are benign, slow-growing and usually asymptomatic tumors, but in some cases bleeding, epigastric pain and palpable mass may occur.

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Preoperative diagnosis is challenging due to the difficulty of differentiation from other sub-mucosal tumors.

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The size and location of the tumor, as well as its relation to the surrounding organs, are essential factors in determining the type of operation.

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Local extirpation, wedge resection, partial, subtotal or even total gastrectomy, are all acceptable operations.

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Gastric schwannomas have a good prognosis.

Introduction

Gastrointestinal schwannomas are benign, slow-growing and usually asymptomatic tumors. In some cases bleeding, epigastric pain and palpable mass may be occurring. Preoperative diagnosis is challenging due to the difficulty of differentiation from other submucosal tumors. Diagnosis is most often provided through the histology report.

Case presentation

In this study we report two cases of gastric tumors with the suspicion of a GIST preoperatively but histologically confirmed to be gastric schwannomas. Two patients of our study gave to us their written consent for publication. Research work has been reported with the PROCESS criteria.

Discussion

Surgical resection should be considered the mainstay of treatment in patients with gastric schwannomas. Possible complications such as bleeding or pyloric stenosis can be presented. The size and location of the tumor, as well as its relation to the surrounding organs, are essential factors in determining the type of resection.

Conclusion

Gastric schwannomas are usually presented us submucosal mass. Preoperative diagnosis is challenging due to the difficulty of differentiation from other submucosal tumors. Endoscopic Esophagogastroduodenoscopy with biopsy and endoscopic ultrasound is essential to determine the nature of these lesions. Resection of the lesion in healthy borders is the treatment of choice. Patho-logical examination usually revealed positive S-100 protein and negative CD34, CD117, Actin and desmin strains.

Rarity among benign gastric tumors: Plexiform fibromyxoma - Report of two cases

Plexiform fibromyxoma is a very rare mesenchymal tumor of the stomach, found almost exclusively in the antrum/pylorus region. The most common presenting symptoms are anemia, hematemesis, nausea and unintentional weight loss, without sex or age predilection. We describe here two cases of plexiform fibromyxoma, involving a 16-year-old female and a 34-year-old male. Both patients underwent complete resection (R0) by distal gastrectomy and retrocolic gastrojejunostomy (according to Billroth 2); for both, the postoperative course was uneventful. Histology showed multiple intramural and subserosal nodules with characteristic plexiform growth, featuring bland spindle cells situated in an abundant myxoid stroma with low mitotic activity. Immunohistochemistry showed α-smooth muscle actin-positive spindle cells, focal positivity for CD10, and negative staining for KIT, DOG1, CD34, S100, β-catenin, STAT-6 and anaplastic lymphoma kinase. One of the cases showed focal positivity for h-caldesmon and desmin. Upon follow-up, no sign of disease was found. In the differential diagnosis of plexiform fibromyxoma, it is important to exclude the more common gastrointestinal stromal tumors as they have greater potential for aggressive behavior. Other lesions, like neuronal and vascular tumors, inflammatory fibroid polyps, abdominal desmoid-type fibromatosis, solitary fibrous tumors and smooth muscle tumors, must also be excluded.

Plexiform angiomyxoid myofibroblastic tumor of stomach: A rare case

Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a rare benign mesenchymal tumor of stomach. Rarity of this kind of tumors and scarce review articles may cause underrecognition of this entity and pose a real diagnostic challenge to gastroenterologists, pathologists and surgeons when encountering such patients and differentiating PAMT from other gastric intramural tumors. We report a case of 28-year-old woman, who presented with epigastric pain after meals, iron-deficiency anaemia and weight loss. Upper gastrointestinal endoscopy revealed submucosal tumor-like elevated lesion in the anterior wall of the antrum with intact overlying mucosa. Endoscopic ultrasound showed a 3-cm hypoechoic homogenous mass, originating from the third layer of the gastric wall. Endoscopic ultrasound-guided fine needle aspiration was not informative. Endoscopic buttonhole biopsy was performed to obtain specimens. Following this, the unexpected prolapse of the tumor occurred into the lumen of the stomach, causing gastric outlet obstruction - the biopsy was obtained. Pathomorphological features suggested the diagnosis of PAMT. Gastric resection of the Billroth I type was performed. Diagnosis was confirmed by histological analysis of the surgical specimen.

Laparoscopic and Endoscopic Cooperative Surgery for Plexiform Angiomyxoid Myofibroblastic Tumor

Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a recently described distinctive gastric mesenchymal entity with a peculiar plexiform pattern, bland spindle cells and a myxoid stroma rich in arborizing blood vessels. In this study, we report a new case of this rare gastric tumor resected by laparoscopic and endoscopic cooperative surgery (LECS). A 39-year-old Japanese man was admitted with a gastric mass. Gastroscopy showed an elevated mass in the anterior wall of the gastric antrum. Endoscopic ultrasound examination revealed a focal hypoechoic lesion protruding into the lumen. A partial gastrectomy by LECS was performed, and the patient made an uneventful recovery and remains well 9 months later. The tumor in this case depicted all the typical histopathologic and immunochemical features of gastric PAMT (c-kit negative and smooth muscle actin-positive). Especially, it was characterized by multiple nodules protruding outward within the serosa. Therefore, it is important that the resection line is determined on the serosa to ensure the complete resection of these nodules together.

Incidental gastric glomus tumor after laparoscopic sleeve gastrectomy

Gastric glomus tumors (GGTs) are unusual benign, subepithelial, mesenchymal neoplasms of modified smooth muscle cells representing a neoplastic counterpart of glomus bodies. A 38-year-old woman was admitted to our clinic presenting morbid obesity. Routine preoperative evaluations, such as laboratory analysis, abdominal ultrasonography, and upper gastrointestinal endoscopy, were performed. She underwent a classical laparoscopic sleeve gastrectomy (LSG). The postoperative course was uneventful and she was discharged for outpatient control. Her histopathology report revealed a GGT 0.8 cm in diameter. No further treatment was done and she had lost 28 kg at the postoperative sixth month. Here, we present the case of GGT, which was diagnosed incidentally after LSG.

Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) of Stomach with Synchronous Bilateral Cystic Ovarian Neoplasms, a Rare Case Presentation

Plexiform Angiomyxoid Myofibroblastic Tumor (PAMT) is a recently identified mesenchymal tumor of the stomach, which was first described in the year 2007 and was added in the 2010 WHO classification of tumors of the digestive system World J Gastroenterol 16(6): 2835-2840, 2010. It closely resembles with other gastric tumors but distinctly varies in clinical management as well as the histopathology. We had a 51 year, female patient, laborer by profession with low socio economic status, who had abdominal pain with vomiting since 6 months. She had similar complaints 3 years ago for which she was evaluated and presumed to have Carcinoma Stomach and underwent laparotomy which ended up only with Gastro- Jejunal anastomosis. She was admitted at our institution. Endoscopy revealed antral bulge with central area ulceration and biopsy was taken which was not confirmatory for malignancy. CT images showed heterogeneous mass with necrotic changes arising from the duodenum favored the diagnosis of perigastric neoplasm. PET CT was done, 8.4 × 5 × 6.1 cm exophytic mass in the pyloric region of stomach with solid and cystic components causing significant gastric outlet obstruction. She underwent exploratory laparotomy and complete excision of mass with achievement of R0 clearance. Histopathology was reported as Plexiform angiomyxoid myofibroblastic tumor (PAMT).

Plexiform fibromyxoma: report of two pediatric cases and review of the literature

Plexiform fibromyxoma is a distinctive mesenchymal neoplasm usually arising in the gastric antrum. We report 2 cases of this entity in pediatric patients, including the first case arising in the esophagus. The patients were a 16-year-old female who presented with chest pain and was found on computed tomographic scan to have a midesophageal mass at the level of the carina, and an 11-year-old female with a gastric mass. Both patients underwent surgical resection of their tumors, which histologically exhibited a plexiform growth pattern with multiple nodules in the muscularis propria and infiltrative borders. The nodules were composed of a rich myxoid stroma with bland uniform spindle cells, no mitoses or necrosis, and delicate blood vessels in the background. Immunohistochemical studies demonstrated that the tumor cells were immunoreactive with smooth muscle actin and not reactive with S-100, CD34, desmin, and c-kit (CD117). We report the first case of plexiform fibromyxoma originating in the esophagus, emphasize its occurrence in pediatric patients, and review the related literature.

A rare large tracheal glomus tumor with postoperative haematemesis

Glomus tumors are uncommon benign tumors which usually arise from the distal portion of the digits. A tracheal glomus tumor with large size is extremely rare. We present a case of a large tracheal glomus tumor that was resected using posterolateral thoracotomy and successful primary reconstruction of the trachea was achieved. Severe haematemesis happened after the patient was discharged. An emergency exploratory thoracotomy was performed but no signs of anastomotic bleeding were observed, while intraoperative gastroscopy revealed plenty of blood and blood clots in the patient's stomach. Medical treatments targeting hemorrhage of upper digestive tract were given and the patient finally recovered.