Benign Subepithelial Tumors Research Articles

Natural history of gastric leiomyoma.

Most gastric leiomyomas are asymptomatic and benign subepithelial tumors (SETs); however, some may increase in size or become symptomatic. Understanding their natural history is therefore important to their management. We investigated the natural history of histologically proven gastric leiomyomas. We retrospectively reviewed histologically proven gastric leiomyoma cases at a tertiary center. The baseline characteristics of these cases were analyzed, and those with a follow-up period of at least 12months without immediate resection were evaluated. The primary outcome was the frequency of size increase of more than 25% during the follow-up period, and the secondary outcome was the histopathologic results in cases that underwent resection. Among the 231 patients with histologically proven gastric leiomyomas, the most frequent location was the cardia (77.1%), and the median size was 3cm (IQR 2-4cm). Eighty-four cases were followed up over a median period of 50.8months (IQR 27.2-91.3months). During the follow-up period, tumor size increased in two cases (2.4%). Surgical results showed that one case was leiomyoma, and the other was leiomyosarcoma. Among the remaining cases without change in size, 15 underwent surgical resection (n = 10) or endoscopic resection (n = 5), and all cases were confirmed as leiomyoma. Most gastric leiomyomas are benign SETs, and an increase in size is not frequent, even in large-sized cases. Close monitoring with routine follow-up without resection may be sufficient in cases of histologically proven gastric leiomyoma. However, in cases of ulceration or size increase, resection may be beneficial.

Natural history of gastric leiomyoma.

262 Background: Most gastric leiomyomas are asymptomatic and benign subepithelial tumors (SETs); however, some may increase in size or become symptomatic. Understanding their natural history is therefore important to their management. We investigated the natural history of histologically proven gastric leiomyomas. Methods: We retrospectively reviewed histologically proven gastric leiomyoma cases at a tertiary center. The baseline characteristics of these cases were analyzed, and those with a follow-up period of at least 12 months without immediate resection were evaluated. The primary outcome was the frequency of size increase of more than 25% during the follow-up period, and the secondary outcome was the histopathologic results in cases that underwent resection. Results: Among the 231 patients with histologically proven gastric leiomyomas, the most frequent location was the cardia (77.1%), and the median size was 3 cm (IQR 2–4 cm). Eighty-four cases were followed up over a median period of 50.8 months (IQR 27.2–91.3 months). During the follow-up period, tumor size increased in two cases (2.4%). Surgical results showed that one case was leiomyoma, and the other was leiomyosarcoma. Among the remaining cases without change in size, 15 underwent surgical resection (n = 10) or endoscopic resection (n = 5), and all cases were confirmed as leiomyoma. Conclusions: Most gastric leiomyomas are benign SETs, and an increase in size is not frequent, even in large-sized cases. Close monitoring with routine follow-up without resection may be sufficient in cases of histologically proven gastric leiomyoma. However, in cases of ulceration or size increase, resection may be beneficial.

Can Perfusion CT Differentiate GIST from Other Benign Subepithelial Tumors in the Stomach?

Purpose: To evaluate the diagnostic performance of perfusion computed tomography (PCT) parameters for differentiating gastrointestinal stromal tumors (GISTs) from other benign subepithelial tumors (SETs) in the stomach.Materials and Methods: Thirty-one patients with gastric SETs subsequently confirmed via surgery underwent PCT using a multidetector computed tomography (CT) scanner at 80 kVp. Two radiologists analyzed key CT features including homogeneity and degree of enhancement. PCT parameters including blood flow, blood volume, mean transit time, and permeability surface value (PS) were independently calculated by two other radiologists. Comparative analysis of the CT features and perfusion parameters of GISTs and other benign SETs was then performed. Diagnostic performances of the perfusion parameters were also evaluated using receiver operating characteristic (ROC) analysis.Results: Twenty-four patients were proven to have GISTs via histologic examination, while the remaining non-GISTs included 3 leiomyomas, 3 schwannomas, and 1 totally necrotic nodule. Among the conventional CT features, lymphadenopathy was more frequent in non-GISTs (2/7, 28.6%) than in GISTs (0/24, 0%) (p = 0.045). Among the PCT parameters, the mean PS in the areas of strongest enhancement of GISTs (25.3 ± 23.9 mL/100 g/min) was significantly higher than that of other SETs (8.8 ± 8.8 mL/100 g/min) (p = 0.029). In ROC analysis, an area under the curve of 0.774 (p = 0.03), sensitivity of 91.7%, and specificity of 57.1% were achieved when the PS cut-off was set at 7.17 mL/100 g/min.Conclusions: Perfusion parameters were helpful for differentiating GISTs from other benign SETs, as GISTs exhibited significantly higher PS than non-GISTs.

Endoscopic submucosal dissection of a symptomatic giant colonic lipoma: technical tips for resection and specimen retrieval.

Video 1Endoscopic submucosal dissection of a giant colonic lipoma.

Endoscopic unroofing and mucosal resection for a large colonic lipoma with intussusception: an effective hybrid technique.

Lipomas account for 4% of benign subepithelial tumors of the GI tract and are found mainly in the colon (65%-75%).1 Colonic lipomas are often found incidentally during colonoscopy and are often asymptomatic and <20 mm in size and therefore do not require routine colonoscopy or treatment.2 However, in rare cases, colonic lipoma may grow to the point of being symptomatic.

2785 Vanek's Tumor: A Rare Presentation of Abdominal Pain and Reflux Disease

INTRODUCTION: Inflammatory fibroid polyps (IFPs), or Vanek’s tumors, are benign subepithelial tumors most commonly found in the stomach and small intestine. Histologically, they classically demonstrate spindle cell onion skinning with an abundance of eosinophilic infiltration. IFPs are most commonly found incidentally upon endoscopic evaluation, but may drive certain symptoms such as early satiety or epigastric pain depending on position. We describe a case of IFP successfully removed from the gastric antrum of a patient presenting with reflux and pain with resolution of symptoms after polypectomy. CASE DESCRIPTION/METHODS: A 47-year-old female with a history of gastroesophageal reflux with poor symptom control despite high dose twice daily proton pump inhibitor (PPI) therapy presented to the clinic for evaluation of worsening reflux. She also endorsed epigastric discomfort, chronic cough, and laryngitis. Her last upper endoscopy in 2015 was normal. Upper endoscopy was completed, which revealed the presence of a single pedunculated polyp measuring 1.2 cm in the gastric antrum near the pylorus. Polyp was removed with hot snare cautery and the residual defect was closed with clips. Given the endoscopic appearance, the lesion was initially thought to be hyperplastic. On pathologic review, the architecture and immunohistochemical profile was most consistent with an IFP. On follow-up several weeks later, the patient had improved reflux and abdominal pain symptoms and was then weaned off of her PPI without return of symptoms after several months. DISCUSSION: Although IFPs were initially postulated to be robust host responses to local injury with resultant inflammation, recent evidence has shown that IFP proliferation is driven by an activating mutation in the platelet derived growth factor receptor alpha (PDGFRA), which is suggestive of a neoplastic and possibly insidious etiology. While most are found incidentally and there are no guidelines on surveillance of these lesions, any large polyp in the stomach should be removed to reduce the risk of progression to malignancy. Furthermore, polyp removal may result in symptom improvement. Whether our patient’s symptom resolution was placebo-driven or actually a result of the IFP removal, our patient demonstrated a remarkable improvement exclusively with IFP polypectomy.

Contrast Enhanced Endoscopic Ultrasound Imaging for Gastrointestinal Subepithelial Tumors.

Subepithelial tumors are divided into benign subepithelial and potentially malignant gastrointestinal stromal tumors. It is difficult to distinguish between these tumor types. Contrast-enhanced harmonic endoscopic ultrasound is reportedly useful for diagnosing subepithelial tumors, can be safely and easily performed by understanding the principle and method, and can be used to distinguish between tumor types with high sensitivity on the basis of differences in contrast effect. The generated image shows a hyper-enhancement pattern in gastrointestinal stromal tumors (sensitivity, 78%–100%; specificity, 60%–100%; accuracy, 60%–100%) and hypo-enhancement pattern in benign subepithelial tumors. Contrast-enhanced harmonic endoscopic ultrasound can be used to estimate the malignancy potential of gastrointestinal stromal tumors by evaluating the uniformity of the contrast and the blood vessels inside the tumor, with abnormal intra-tumor blood vessels, heterogeneous enhancement, and non-enhancing spots suggesting malignancy. Contrast-enhanced harmonic endoscopic ultrasound has a higher sensitivity than other imaging modalities for the detection of vascularity within gastrointestinal stromal tumors. Additionally, it has been reported that treatment effects can be estimated by evaluating the blood flow in the gastrointestinal stromal tumor before and after treatment with tyrosine kinase inhibitors using contrast-enhanced ultrasound. However, there will be subjective-bias and the results depends on the performer’s skill.

Differentiation of large (≥5 cm) gastrointestinal stromal tumors from benign subepithelial tumors in the stomach: Radiologists’ performance using CT

PurposeTo identify significant CT findings for the differentiation of large (≥5cm) gastric gastrointestinal stromal tumors (GIST) from benign subepithelial tumors and to assess whether radiologists’ performance in differentiation is improved with knowledge of significant CT criteria. Materials and methodsOne-hundred twenty patients with pathologically proven large (≥5cm) GISTs (n=99), schwannomas (n=16), and leiomyomas (n=5) who underwent CT were enrolled. Two radiologists (A and B) retrospectively reviewed their CT images in consensus for the location, size, degree and pattern of enhancement, contour, growth pattern and the presence of calcification, necrosis, surface ulceration, or enlarged lymph nodes. CT findings considered significant for differentiation were determined using uni- and multivariate statistical analyses. Thereafter, two successive review sessions for the differentiation of GIST from non-GIST were independently performed by two other reviewers (C and D) with different expertise of 2 and 9 years using a 5-point confidence scale. At the first session, reviewers interpreted CT images without knowledge of significant CT findings. At the second session, the results of statistical analyses were provided to the reviewers. To assess improvement in radiologists’ performance, a pairwise comparison of receiver operating curves (ROC) was performed. ResultsHeterogeneous enhancement, presence of necrosis, absence of lymph nodes, and mean size of ≥6cm were found to be significant for differentiating GIST from schwannoma (P<0.05). Non-cardial location, heterogeneous enhancement, and presence of necrosis were differential CT features of GIST from leiomyoma (P<0.05). Multivariate analyses indicated that absence of enlarged LNs was the only statistically significant variable for GIST differentiating from schwannoma. The area under the curve of both reviewers obtained using ROC significantly increased from 0.682 and 0.613 to 0.903 and 0.904, respectively, with information of the significant CT findings differentiating GISTs from non-GISTs (P<0.001). ConclusionNon-cardial location, heterogeneous enhancement, presence of necrosis, larger lesion size, and absence of lymphadenopathy are highly suggestive CT findings for large GISTs in differentiation from schwannomas or leiomyomas. Regardless of radiologists’ expertise, diagnostic performance in differentiation can be significantly improved with knowledge of these CT findings.

707 Is Esophago-Gastro-Duodenoscopy Prior to Roux-en-Y Gastric Bypass Mandatory?

Surgical resection for benign subepithelial tumors near the gastroesophageal junction is difficult, often leading to esophagectomy. Here we demonstrate the feasibility of a novel technique of dual endoscopic resection using retroflexed standard adult upper endoscope and second smaller caliber (baby) endoscope to resect benign GE junction leiomyomas (26 cm size) in four patients. Maneuvering the small caliber endoscope allowed offaxis retraction of the mass while the adult endoscope was used to carry out the dissection from the submucosal tissue. Our experience highlights the feasibility of this minimally invasive approach by enabling triangulation using endoscopic tools.

605 Dual-Scope Endoscopic Resection of Benign GE Junction Tumors (With Video)

Surgical resection for benign subepithelial tumors near the gastroesophageal junction is difficult, often leading to esophagectomy. Here we demonstrate the feasibility of a novel technique of dual endoscopic resection using retroflexed standard adult upper endoscope and second smaller caliber (baby) endoscope to resect benign GE junction leiomyomas (26 cm size) in four patients. Maneuvering the small caliber endoscope allowed offaxis retraction of the mass while the adult endoscope was used to carry out the dissection from the submucosal tissue. Our experience highlights the feasibility of this minimally invasive approach by enabling triangulation using endoscopic tools.

607 Etamis: Transanal Minimally Invasive Surgical Submucosal Excision of a Large, Circumferential, Rectal Adenoma With Endoscopic Visualization

Surgical resection for benign subepithelial tumors near the gastroesophageal junction is difficult, often leading to esophagectomy. Here we demonstrate the feasibility of a novel technique of dual endoscopic resection using retroflexed standard adult upper endoscope and second smaller caliber (baby) endoscope to resect benign GE junction leiomyomas (26 cm size) in four patients. Maneuvering the small caliber endoscope allowed offaxis retraction of the mass while the adult endoscope was used to carry out the dissection from the submucosal tissue. Our experience highlights the feasibility of this minimally invasive approach by enabling triangulation using endoscopic tools.