As mentioned, the vast majority of leiomyomas are asymptomatic, but the most common symptoms are anemia due to gastric ulceration and subsequent hemorrhage, together with pain that is nonspecific and occasional dyspepsia [1]. Dysphagia, esophageal reflux, and retrosternal burning are scarcely reported. The tumor has a very long growth period and only tumors with a very large diameter are shown to cause symptoms.

• Asymptomatic

  Gastric leiomyomas are rare benign tumors of the stomach that have an asymptomatic course in most cases, but anemia, bleeding, and gastric ulceration may be seen. [symptoma.com]

  Most leiomyomas are asymptomatic and are found at autopsy or on abdominal exploration for other reasons. Indications for resection include large size and symptoms of compression, obstruction, or hemorrhage. [ncbi.nlm.nih.gov]

  Most leiomyomas are found incidentally in asymptomatic patients. Symptoms related to a gastric leiomyoma will depend on the tumor size, location, and presence/absence of ulcerations. [radiopaedia.org]

  More often it is taught that a tumor of this type is usually asymptomatic and that it is seen as a rule only incidentally at autopsy. [jamanetwork.com]

• Lymphadenopathy

  The absence of lymphadenopathy and the presence of necrosis can be used as differential point of GIST from gastric schwannoma which is the second most common mesenchymal tumor of the stomach (Choi et al. 2012 ). 7.2 Schwannoma Gastrointestinal schwannoma [radiologykey.com]

  […] differential considerations include: gastrointestinal leiomyoma most common in the esophagus, accounting for 75% of mesenchymal tumors 1 rare in the remainder of the GI tract gastrointestinal leiomyosarcoma : rare gastrointestinal lymphoma / gastric lymphoma lymphadenopathy [radiopaedia.org]

  Computed Tomography scans of the chest show in most cases a mass originating from esophagus without mediastinal lymphadenopathy, but in giant leiomyoma, tumor usually grow toward outside of esophageal lumen. [jtd.amegroups.com]

  Lymphadenopathy was not observed. The differential diagnosis involved mesenchymal and other benign gastrointestinal stromal tumors. [wjso.biomedcentral.com]

  EUS has the ability to differentiate extramural compression from intramural growth, determine layer of origin, provides information regarding echogenicity and vascularity, accurately size the lesion and evaluate regional lymphadenopathies. 4,5 Some authors [elsevier.pt]

• Pallor

  He had gross pallor. Abdominal examination revealed epigastric distention and a tympanic mass in the epigastric area was appreciated. Bowel sounds were sluggish and per-rectal examination was normal. His hernia orifices were normal. [ispub.com]

  食道損傷 esophageal perforation食道穿孔 esophageal varices食道静脈瘤 esophagitis食道炎 esophagography食道造影 excretory duct導管 exocrine gland外分泌腺 external biliary fistula外胆汁瘻 extracorporeal shock wave lithotripsy (ESWL)体外衝撃波結石破砕術（ESWL） extrahepatic bile duct肝外胆管 f facial pallor [tokyo-med.ac.jp]

• Aspiration

  The 47-year-old patient underwent endoscopic ultrasonography with fine needle aspiration (FNA). The inmunohistochemical analysis excluded a GIST. [websurg.com]

  In these times, a book should aspire to present the most significant advances in the field, reflect the themes of the moment, and provide a useful compendium for future reference. [books.google.it]

  The efficacy of fine-needle aspiration with endoscopic ultrasound is controversial. [healio.com]

  Senturk Concordance of endoscopic ultrasonography-guided fine needle aspiration diagnosis with the final diagnosis in subepithelial lesions [18] L. Fuccio, A. [elsevier.pt]

• Hematemesis

  Larger tumors are more prone to have associated ulcerations and thus cause bleeding, which can manifest clinically as hematemesis, melena, and iron-deficiency anemia. [radiopaedia.org]

  A 67-years-old patient was admitted to our attention due to two episodes of hematemesis and melena occurred in the previous two days. [ncbi.nlm.nih.gov]

  As the patient had suffered three attacks of hematemesis, two of which had been so severe as to reduce him to a state of shock, exploration [jamanetwork.com]

  CASE REPORT Year : 2016 | Volume : 23 | Issue : 1 | Page : 49-51 Gastric leiomyoma presenting with massive hematemesis in a Nigerian 1 Consultant Gastroenterologist, ReMay Consultancy and Medical Services, Opebi, Ikeja, Nigeria 2 Consultant Radiologist [wajradiology.org]

• Epigastric Pain

  Abstract A 62 year-old man was admitted with the chief complaint of a epigastric pain and difficulty of swallowing. [ncbi.nlm.nih.gov]

  The main symptoms are epigastric pain, nausea, vomiting, weight loss, sideropenic anaemia, epigastric palpable mass. [web.tiscali.it]

  Most patients remain asymptomatic and when they become symptomatic, the main signs are usually dysphagia and epigastric pain, but they are not specific to the disease. Malignization is rare but should not be ignored. [websurg.com]

  Epigastric pain was a prominent symptom in four patients. [jpma.org.pk]

  Dysphagia with concomitant epigastric pain or retrosternal burning usually appears when the tumor's diameter becomes larger than the critical point of 4.5-5 cm ( 10 ). [jtd.amegroups.com]

• Melena

  Larger tumors are more prone to have associated ulcerations and thus cause bleeding, which can manifest clinically as hematemesis, melena, and iron-deficiency anemia. [radiopaedia.org]

  A 67-years-old patient was admitted to our attention due to two episodes of hematemesis and melena occurred in the previous two days. [ncbi.nlm.nih.gov]

  […] digestive tube peristalsis uncoordinated abdominal pain black shock The clinical manifestations of leiomyoma often with the tumor site, size, growth pattern, the type of complications related to bleeding as the most common symptoms, can cause hematemesis or melena [healthfrom.com]

  We describe a 72-year-old patient who presented with episodes of melena and was subsequently investigated for a tumor of the antrum of the stomach. [wjso.biomedcentral.com]

  Zhu HN, Yu JP, Luo J, Jiang YH, Li JQ, Sun WY: Gastric adenomyoma presenting as melena: a case report and literature review. World J Gastroenterol 2010;16:1934-1936. [karger.com]

To make the diagnosis of gastric leiomyoma, several steps in the workup should be made. Initial evaluation can be conducted through various imaging studies, such as computed tomography or abdominal ultrasonography that may reveal the presence of a subepithelial or intraluminal mass [5]. Virtually all cases of upper gastrointestinal bleeding, however, should be evaluated through endoscopy, a minimally invasive procedure that provides a direct view into the esophageal and gastric mucosa [8]. Because tumor differentiation cannot be made by macroscopic appearance, biopsy, and subsequent immunohistochemical staining is imperative in defining the type of the tumor. Leiomyomas have very similar microscopic characteristics compared to GISTs, but the vital distinguishing feature on immunohistochemistry is negative staining for c-Kit, a proto-oncogene that gives GISTs their malignant potential [9]. Rare cases, however, have confirmed positive c-KIT staining in gastric leiomyoma [10], which is why other features, such as positive desmin and α-smooth muscle actin staining, together with negative s100 staining, are important in further differentiating the tumor. Once a definite diagnosis is made, appropriate treatment procedures may be initiated.

• Gastric Lesion

  The preoperative endoscopic marking of gastric lesions, facilitates the intraoperative localization and resection of these lesions. [ncbi.nlm.nih.gov]

  A: Upper gastrointestinal endoscopy showing an expansive lesion with irregular, ulcerated mucosa in the greater curvature of the gastric body (arrow). [rb.org.br]

  All patients with a submucosal gastric lesion where there is a suspicion of GIST should undergo an abdominal CT scan to help guide further treatment even if EUS has been performed. [healio.com]

  Karger AG, Basel Introduction Gastric adenomyoma (GA) is a rare benign lesion composed of ducts and glands embedded in smooth muscle stroma. [karger.com]

  Gastric glomus tumors should always be included in the differential diagnosis of submucosal gastric lesions, keeping in mind that preoperative investigation of these patients often yields misleading results. [wjso.biomedcentral.com]

Before making an optimal treatment strategy, various factors have to be considered, including the tumor size, location, and presence of symptoms. Asymptomatic, smaller tumors do not require immediate surgical therapy and can be followed by periodic endoscopy examinations [11]. On the other hand, larger tumors that are symptomatic necessitate excision. When possible, surgical excision through an endoscopic approach is favorable due to the fact that it is minimally invasive compared to laparoscopy and open surgery. One of the major limitations of endoscopic surgery is the risk of severe bleeding when leiomyomas are adjacent to the serosa and the adventitia, having in mind that they arise from the muscularis propria or the muscularis mucosae [6]. Laparoscopic surgery provides significant benefit over open surgery due to reduced risks while being less invasive and most efficient approaches include laparoscopic wedge resection, intragastric resection, and gastrotomy with resection [1]. In some cases, when particularly large tumors are located in tricky areas for operation, a combined approach may be necessary,

Leiomyomas of the stomach are benign, their malignant potential is minimal and adequate therapy can efficiently remove the tumor, all indicating a very good prognosis. Moreover, certain studies estimated that up to 90% of tumors remain asymptomatic throughout life [6], and the diagnosis can often be made incidentally.

Gastric leiomyoma stems from either the lamina muscularis mucosae when it is termed to be superficial, or it may arise from muscularis propria, in which case it is a deep tumor [2]. The exact cause of tumor development remains unknown. In virtually all cases, this tumor appears as a small, solitary lesion and histological inspection reveals well-differentiated smooth muscles with eosinophilic cytoplasm, very scarce mitotic activity and myofibrillar absence [1]. These features indicate that the tumor is almost exclusively benign, but the malignant transformation was reported in a few cases [1].

These benign tumors comprise approximately 2.5% of all gastric neoplasms, but they are one of the most common benign stomach tumors encountered [1]. Because gastric leiomyomas are rarely encountered in practice, epidemiological data mainly rest on sporadic case reports. In fact, a crude incidence rate estimates that this tumor appears in approximately 3 per million individuals [1]. It is somewhat more frequently seen in male individuals between 50-70 years [4], while ethnic predilection has not been established. The sixth decade of life is the period in which the highest incidence rates are observed, but patients of any age may be affected. The tumor may develop at any site in the stomach, but the corpus and antrum are shown to be the most common sites of occurrence [4].

Not much is known about the pathogenesis of gastric leiomyomas, apart from the fact that they arise as round, solitary lesions in the lamina muscularis mucosa and muscularis propria. The microscopic appearance that includes an abundance of hyperplastic smooth muscle cells with minimal mitotic activity and reduced expression of c-Kit have shown to be primary factors for its benign nature [7], but which mechanisms lead to is development remain unclear.

As the exact pathophysiological mechanism of development is unclear, current preventive strategies do not exist. Although wide-scale screening of elderly patients could be considered as a preventive measure, screening for this particulate tumor may not be necessary, as it causes very little harm to the patient due to its asymptomatic course and very little potential for malignant transformation.

Gastric leiomyomas are rare tumors of the stomach and comprise about 2.5% of all gastric neoplasms [1]. These tumors originate either from the muscularis mucosae or the muscularis propria, based on which they can be classified as superficial and deep, respectively [2]. Both macro- and microscopically, leiomyomas closely resemble gastrointestinal stromal tumors (GISTs) that develop from mesenchymal cells and have oncogenic potential. The main distinguishing characteristic is the expression of the tyrosine-protein kinase Kit or proto-oncogene gene c-Kit, a stem-cell growth factor that is present in GISTs [3], but not in leiomyomas, making this tumor almost universally benign. Epidemiology data is composed of scarce case reports and some rough estimates suggest that the incidence rate is approximately 3 per one million individuals [1]. Certain studies have established that the sixth decade of life is the period in which tumor development is most common, but patients of any age may be affected [1]. In terms of tumor localization, the corpus is a common site of occurrence, while the cardia and the antrum are reported as well [4] [5]. An asymptomatic course is seen in most cases, whereas symptoms such as anemia due to mucosal ulceration and gastrointestinal hemorrhage may be seen in up to 50% of cases [4]. To make the diagnosis, endoscopic ultrasonography (EUS) is the initial method choice that can identify the location and the extent of tissue involvement. The tumor appears as a homogenous and hypoechoic lesion with clear margins on EUS. Additional immunohistochemical staining, however, must be performed to distinguish it from GISTs. Positive staining for α-smooth muscle actin and desmin, with a negative staining s100 proteins, in addition to c-Kit, are criteria for the diagnosis of gastric leiomyoma. Treatment principles primarily depend on the size of the tumor, but complete surgical excision is the optimal treatment method. Endoscopic approach is performed, if possible because it is minimally invasive. For patients in whom the location and size of the tumor increase the chance of adverse effects, such as bleeding, a laparoscopic approach may be indicated [6]. Gastric leiomyoma has a good prognosis, as the vast majority of these tumors are discovered incidentally and do not cause any symptoms, with a minimal potential for malignant transformation.

Gastric leiomyoma is a very rare tumor of smooth muscle cells located in the stomach and is established to occur in about 3 per one million individuals. The exact cause is not known, but it is most frequently diagnosed in elderly patients between 50-70 years of age. Although this tumor shares several characteristics with gastrointestinal stromal tumors (GISTs) that have significant potential for malignant transformation, it is considered to be universally benign, with very rare reports of progression into malignant neoplasms. It is estimated that the vast majority of individuals with this tumor are undiagnosed, as symptoms are rarely reported. However, in the case of larger tumors that cause ulceration of the gastric mucosa, anemia, bleeding, swallowing difficulties and pain may be reported. To make the diagnosis, initial imaging studies such as ultrasonography and computed tomography (CT scan) scan may identify a mass in the stomach. An endoscopic ultrasound, the diagnostic procedure of choice, includes insertion of an endoscope through the throat and into the stomach, can further distinguish between various types of tumors, but the definite diagnosis can be made after performing a biopsy. A specific method called immunohistochemistry is the ultimate diagnostic tool, identifies specific tumor molecules that can distinguish leiomyoma from other tumors, mainly GISTs. Once the diagnosis is made, treatment depends on the location and size of the tumor, as well as the severity of symptoms. The goal of treatment is to abolish symptoms, if present and remove the tumor from the stomach, which can be done by and endoscopic or laparoscopic surgery. Endoscopic surgery is the least invasive form of surgical therapy, but it may not always be carried out, as these tumors carry a high risk of bleeding when performing this procedure in some patients. For these reasons, laparoscopy and resection of the tumor are most frequently performed. Overall, patients with this tumor have a very good prognosis, as it very rarely causes symptoms and has little a potential for malignant transformation.

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