Diagnosis Of Gastrointestinal Stromal Tumors Research Articles

DOG1 expression is in common human tumors: A tissue microarray study on more than 15,000 tissue samples

Abstract Introduction/Objective Introduction: DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumors (GIST) derived from Cajal cells. Methods/Case Report Methods: To systematically determine in what tumor entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Results (if a Case Study enter NA) Results: DOG1 immunostaining was found in 67 tumor types including GIST (95.7%), esophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the Papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), esophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumor entities. DOG1 expression was unrelated to histopathological parameters of tumor aggressiveness and/or patient prognosis in cancers of the breast (n=1,002), urinary bladder (975), ovary (469), endometrium (173), stomach (233), and thyroid gland (512). Conclusion High DOG1 expression was linked to estrogen receptor expression in breast cancer (p<0.0001) and absence of HPV infection in squamous cell carcinomas (p=0.0008). In conclusion, our data identify several tumor entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumors, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.

DOG1 expression is common in human tumors: A tissue microarray study on more than 15,000 tissue samples

DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumors (GIST) derived from Cajal cells. To systematically determine in what tumor entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. DOG1 immunostaining was found in 67 tumor types including GIST (95.7%), esophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the Papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), esophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumor entities. DOG1 expression was unrelated to histopathological parameters of tumor aggressiveness and/or patient prognosis in cancers of the breast (n = 1002), urinary bladder (975), ovary (469), endometrium (173), stomach (233), and thyroid gland (512). High DOG1 expression was linked to estrogen receptor expression in breast cancer (p < 0.0001) and absence of HPV infection in squamous cell carcinomas (p = 0.0008). In conclusion, our data identify several tumor entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumors, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.

Scoring systems for differentiating gastrointestinal stromal tumors and schwannomas from leiomyomas in the stomach.

There is no practical predictive model for the diagnosis of gastrointestinal stromal tumors (GISTs). To establish a practical predictive model for the diagnosis of subepithelial lesions in the stomach, we reviewed patients with GISTs (n = 89), schwannomas (n = 7), and leiomyomas (n = 28).The tumor was more frequently found along the gastric cardia in the leiomyoma group (57.1%) than in the GIST/schwannoma group (2.1%, P < .01). Contrast enhancement (57.3% vs 0%, P < .01) and intra-tumoral necrosis (34.4% vs 0.0%, P < .01) were more frequently observed in the GIST/schwannoma group than in the leiomyoma group. On endoscopic ultrasonography, 58.3% of GISTs/schwannomas showed uneven echogenicity, whereas the echogenicity was uneven in 21.4% of leiomyomas (P < .01). There were no differences between the tumor color and the presence or absence of ulcer formation, tumor bleeding, irregularity of the tumor margin, cystic spaces, and hyperechoic spots between the 2 groups. Based on these results, we developed a 2-step diagnostic algorithm for GISTs/schwannomas. The first step comprises 1 endoscopic feature: a cardiac or non-cardiac location. Tumors with a cardiac location were judged as leiomyomas and those with a non-cardiac location were judged as GISTs/schwannomas, with 96.9% sensitivity and 57.1% specificity for GIST/schwannoma diagnosis. The second step comprises a combination of endoscopic (non-cardiac location), radiologic (positive contrast enhancement and intra-tumoral necrosis), and endosonographic (uneven echogenicity) features for a total of 4 points. We assigned 1 point to each feature. Tumors with scores of 2 to 4 were judged as GISTs/schwannomas, with 81.3% sensitivity and 92.9% specificity for GIST/schwannoma diagnosis.Our predictive model will be a practical guide for the management of gastric subepithelial lesions.

Differentiating Gastrointestinal Stromal Tumors from Leiomyomas Using a Neural Network Trained on Endoscopic Ultrasonography Images

Background: Endoscopic ultrasonography (EUS) is crucial to diagnose and evaluate gastrointestinal mesenchymal tumors (GIMTs). However, EUS-guided biopsy does not always differentiate gastrointestinal stromal tumors (GISTs) from leiomyomas. We evaluated the ability of a convolutional neural network (CNN) to differentiate GISTs from leiomyomas using EUS images. The conventional EUS features of GISTs were also compared with leiomyomas. Patients and Methods: Patients who underwent EUS for evaluation of upper GIMTs between 2010 and 2020 were retrospectively reviewed, and 145 patients (73 women and 72 men; mean age 54.8 ± 13.5 years) with GISTs (n = 109) or leiomyomas (n = 36), confirmed by immunohistochemistry, were included. A total of 978 images collected from 100 patients were used to train and test the CNN system, and 384 images from 45 patients were used for validation. EUS images were also evaluated by an EUS expert for comparison with the CNN system. Results: The sensitivity, specificity, and accuracy of the CNN system for diagnosis of GIST were 92.0%, 64.3%, and 86.98% for the validation dataset, respectively. In contrast, the sensitivity, specificity, and accuracy of the EUS expert interpretations were 60.5%, 74.3%, and 63.0%, respectively. Concerning EUS features, only higher echogenicity was an independent and significant factor for differentiating GISTs from leiomyomas (p < 0.05). Conclusions: The CNN system could diagnose GIMTs with higher accuracy than an EUS expert and could be helpful in differentiating GISTs from leiomyomas. A higher echogenicity may also aid in differentiation.

Act following etiquette and change with time: analysis and discussion on the difference between the current guidelines and clinical practice of gastrointestinal stromal tumor

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the gastrointestinal tract. At present, many professional academic groups and associations at home and abroad have released guidelines for the diagnosis and treatment of GIST. In 2020, Gastrointestinal Stromal Tumor Expert Committee of China Society of Clinical Oncology (CSCO) issued the first "CSCO gastrointestinal stromal tumor diagnosis and treatment guidelines" in China. In the same year, NCCN also released the first "NCCN guideline for the diagnosis and treatment of gastrointestinal stromal tumors (first edition in 2021)" by separating GIST-related content from the guideline for soft tissue sarcoma. However, there are many inconsistencies between the guidelines' recommendation and clinical practice in China. For example, in the aspect of diagnosis, the emphasis on and implementation of molecular detection are variable, the format of molecular detection report is not unified or standardized, the selection of detection methods is inappropriate, the diagnosis of wild-type GIST is not standardized, the risk assessment is improper, and the use of EUS-FNA is relatively seldom; in the aspect of drug therapy, there are some problems, such as the lack of standardization in dose and course of targeted drugs, and off-label medication such as cross line therapy; in terms of surgical treatment, there are also some problems, such as the clinical application scenarios of laparoscopic surgery exceed the recommendations of the guidelines, and the general description of surgical intervention of advanced GIST in the guidelines cannot well guide specific clinical practice. In this context, on the one hand, clinicians need to understand the academic frontier and standardize their medical behavior with the latest guidelines; on the other hand, clinicians need to consider the scientific rationale and accessibility of treatment on some clinical problems that are not clear in the guidelines, and take whether patients can benefit the most as the criteria.

Clinicopathological characteristics and prognosis of patients with sporadic multiple primary gastrointestinal stromal tumors

Objective: To investigate the clinicopathological characteristics and prognosis of sporadic multiple primary gastrointestinal stromal tumor (GIST). Methods: A retrospective cohort study was conducted. Case inclusion criteria: (1) postoperative pathological diagnosis of GIST; (2) primary GIST with single lesion or sporadic multiple primary GIST (sporadic GIST was defined as primary GIST other than familial and syndrome-related GIST, and multiple primary GIST was defined as the number of primary GISTs in the same patient ≥ 2); (3) patients with complete clinicopathological data. Those with tumor recurrence or distant metastasis, and with other malignancies were excluded. Medical records of patients with primary GIST who underwent surgical resection in the Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2010 to December 2020 were collected. Patients were divided into sporadic multiple primary GIST group and single primary GIST group according to the number of primary GIST lesions. The clinicopathological data and prognosis of the two groups were observed and compared. Results: A total of 1200 patients with primary GIST were enrolled in this study, including 628 males (52.3%) and 572 females (47.7%), with a median onset age of 58 (19-93) years. Among them, 1165 cases (97.1%) were sporadic primary GIST with single lesion; 35 cases (2.9%) were sporadic multiple primary GIST. Among 35 cases of sporadic multiple primary GIST, 3 cases (8.6%) had acid reflux as the first symptom, which was higher than the single primary GIST group (22/1165, 1.9%) (χ(2)=7.437, P=0.006). There were no significant differences in other clinical characteristics between the two groups (all P>0.05). Patients in the sporadic multiple primary GIST group contained a total of 80 primary tumors. Compared with the single primary GIST group, the sporadic multiple primary GIST group had a higher proportion of tumors originating in the stomach [87.5% (70/80) vs. 59.1% (689/1165)], lower proportion of spindle cell in histology [85.0% (68/80) vs. 93.7% (1092/1165)], higher proportion of positive CD34 [97.5% (78/80) vs. 87.6% (1021/1165)], smaller maximum diameter [maximum diameter ≤2.0 cm: 61.2% (49/80) vs. 28.8% (335/1165)], lower mitotic rate [≤5/50 high-power fields (HPF): 93.8% (75/80) vs. 74.5% (868/1165)], lower risk of recurrence [60.0% (48/80) vs. 23.3% (271/1165)], and the differences were all statistically significant (all P<0.05). The 3-year recurrence-free survival rate in the sporadic multiple primary group and the single primary GIST group was 96.6% and 89.3% respectively (P=0.160), and the 3-year overall survival rate was 100.0% and 92.8%, respectively (P=0.088). Conclusions: The most common type of sporadic multiple primary GIST is multiple tumors originating in the stomach at the same time. Compared with primary GIST with single lesion, sporadic multiple primary GIST presents smaller maximum diameter and lower mitotic rate. The prognosis of patients between two groups is not significantly different.

The Value of Endoscopic Ultrasonography in the Endoscopic Resection of Gastrointestinal Stromal Tumors.

ObjectiveThis study aimed to explore the clinical value of endoscopic ultrasonography (EUS) in the endoscopic resection of gastrointestinal stromal tumors (GISTs).MethodsA retrospective study of 92 patients who were confirmed to have GISTs by endoscopic resection after EUS examination was conducted. The preoperative features of the EUS examination, ultrasound diagnosis, endoscopic resection methods, surgical procedures, complications, and complete degree of lesion resection were recorded. And 16 patients who were diagnosed by endoscopy and EUS and confirmed by surgical operation were included and analyzed in the subsequent part of the investigation (gastroscopy and EUS image analysis, EUS image and risk classification).ResultsThe preoperative diagnosis rate of EUS and postoperative pathological diagnosis of GISTs was 78.7% (85/108), and the presence of a non-homogeneous echo and liquid anechoic zone in GISTs often indicated higher risk (P < 0.05). There was a positive correlation between tumor size and risk (P < 0.05).ConclusionThe endoscopic resection of GISTs is feasible and safe. EUS is of great significance for the diagnosis and risk assessment of GISTs and can assist in the endoscopic resection of GISTs.

The predictive value of MSCT imaging features on the pathological risk of gastrointestinal stromal tumors

Objective To investigate the predictive value of MSCT imaging features on the pathological risk of gastrointestinal stromal tumors (GISTs). Methods The MSCT manifestations of 120 GISTs patients confirmed by operation, pathology and immunohistochemistry were analyzed retrospectively. The age of tumor onset, location, maximum diameter, morphology, growth pattern, cystic necrosis, calcification, peritumoralfat space, enhancement pattern, peritumoralor intratumoral vessels, peak period of enhancement, metastasis, and the relationship between Ki-67 proliferation index and pathological risk grade were also analyzed. Results Among 120 cases, there were 55 cases of extremely low and low risk, 28 cases of moderate risk, and 37 cases of high risk. There were significant differences in location, tumor diameter, morphology, growth pattern, cystic necrosis, peritumoral fat space, enhancement pattern, peritumoral or intratumoral vessels, peak period of enhancement, and Ki-67 proliferation index of GISTs ( P < 0.05). There was no significant difference in calcification, CT plain scan, enhanced scan (3 phase), peak value and Ap、Vp、Dp of GISTs with different risk ( P > 0.05). Conclusion There are differences in the performance of multi-layer spiral CT (MSCT) in GISTs with different risk levels. It is closely related to the classification of pathological risk. For the diagnosis of GISTs, clinical treatment plan formulation and prognosis, it has important reference value. 摘要： 目的 探讨 MSCT 影像特征对胃肠道间质瘤 (GISTs) 病理危险度的预测价值。 方法 回顾性分析120例经手 术、病理及免疫组化证实的GISTs患者的MSCT表现, 分析肿瘤的发病年龄、部位、肿瘤最大径、形态、生长方式、囊变 坏死、有无钙化、瘤周脂肪间隙、强化方式、瘤周或瘤内血管、强化峰值所在期、有无转移以及Ki-67增殖指数与病理危 险程度分级之间关系。 结果 120例病例中分别有极低度和低度危险55例, 中度危险28例, 高度危险37例。不同危 险程度GISTs在病变的部位、肿瘤最大径、形态、生长方式、囊变坏死、瘤周脂肪间隙、强化方式、瘤周或瘤内血管以及 强化峰值所在期方面均有统计学差异( P < 0.05); Ki-67增殖指数方面有统计学差异 ( P < 0.05)。而不同危险度的 GISTs在病变有无钙化及CT平扫、增强扫描 (三期) CT值、强化峰值、Ap、Vp、Dp方面无统计学差异( P > 0.05)。 结论 不同危险度的GISTs的多层螺旋CT(MSCT)表现存在差异, 且与病理危险程度分级具有密切关系, 对GISTs 的诊断、临床治疗方案制订及判断预后有重要参考价值。

A multidisciplinary approach in the diagnostic challenge of GIST.

Gastrointestinal stromal tumors (GISTs) are the most common malignant mesenchymal lesions of the gastrointestinal tract. They originate from the interstitial cells of Cajal and are characterized by overexpression of the tyrosine kinase receptor, protein product of c-KIT gene (KIT). In this retrospective study, conducted over a period of 10 years, we retrieved from our database, a total number of 57 patients, admitted and operated in the surgical department of ‘Sf. Pantelimon’ Emergency Clinical Hospital, Bucharest, for digestive tumors, histopathologically confirmed as GISTs. More than half of the cases presented as surgical emergencies and the tumors found during the surgical procedures, which proved to be GISTs, were sometimes difficult to differentiate from other mesenchymal tumors, both for the clinician and the pathologist. The diagnosis of GIST relies mostly on pathology and immunohistochemistry, but also on clinical and imagistic data. The most common emergencies were digestive hemorrhage (associated with gastric location), followed by intestinal obstruction (especially for the ileal localization). The largest dimensions corresponded to gastric location. For selected indications (upper digestive sites), upper digestive endoscopy approaches 100% sensitivity. This study focuses on diagnosis of GISTs sustained by both clinical and imagistic methods, along with histopathology and immunohistochemistry techniques, according to the World Health Organization 2019 criteria. Even though the differential diagnosis of these tumors is challenging, an interdisciplinary cooperation with a multiple approach increases the odds of a correct positive diagnosis.

Gastrointestinal Stromal Tumors-A Mini Review.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. They are potentially malignant, and have an unpredictable evolution. The origin of these tumors is in the interstitial cells of Cajal, which are cells that are interposed between the intramural neurons and the smooth muscle cells of the digestive tract. GISTs are characterized by mutations in the gene c-Kit, but also other mutations, such as those of the platelet-derived growth factor receptor alpha. The most common locations of these tumors are the stomach and small intestine, although they can occur at any level of the digestive tract and occasionally in the omentum, mesentery and peritoneum. Most cases of GISTs are sporadic, and about 5% of cases are part of family genetic syndromes. The correct diagnosis of GIST is determined by histopathological examination and immunohistochemistry. According to histopathology, there are three main types of GISTs: spindle cell type, epithelioid type and mixed type. The therapeutic management of GIST includes surgery, endoscopic treatment and chemotherapy. The prognosis of patients with GIST varies depending on a number of factors, such as risk category, GIST stage, treatment applied and recurrence after treatment.

Diagnosis of gastric submucosal tumors and estimation of malignant risk of GIST by endoscopic ultrasound. Comparison between B mode and contrast-harmonic mode

Backgroundstandard B-mode EUS assessment and EUS-guided tissue acquisition present sub-optimal diagnostic yield in the differential diagnosis of gastric submucosal tumors (SMTs). Aimsto evaluate the performances of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) to differentiate gastric SMTs and predict malignancy risk of gastrointestinal stromal tumors (GIST). Methodsa retrospective analysis was performed retrieving consecutive patients with gastric SMTs who underwent EUS between 2009 and 2014. Patients with available EUS video recordings and histological diagnosis were included. De-identified videos were presented to experts who made a diagnosis on B-mode EUS and CH-EUS. Resultsfifty-four patients (29 female, 64-year-old) were included. Final diagnoses were 40 GISTs (8 high-grade), 9 leiomyomas, 5 rare SMTs. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the differential diagnosis of GIST were 95.0% vs. 85.0%, 57.1% for both techniques, and 85.2% vs. 77.8%, respectively. The sensitivity, specificity, and accuracy of B-mode and CH-EUS for the estimation of the malignancy GISTs risk were 62.5% vs. 100%, 83.3% vs. 82.1%, and 78.9% vs. 86.1%, respectively. ConclusionsCH-EUS showed better diagnostic performance than B-mode EUS in differentiating leiomyomas and risk stratification of GIST. When considering high-grade GISTs, the addition of CH-EUS allowed an improvement in diagnostic accuracy.

Recurrent paediatric gastrointestinal stromal tumour of the stomach after 11-years follow-up period – Case report and review of the literature

Gastrointestinal stromal tumours (GISTs) are the most frequent mesenchymal tumours of the gastrointestinal tract, but they are rare in children. We report a case of a recurrent GIST that was first diagnosed in a 10 years old girl and underwent antrectomy. After 11 years, she again complained of vomiting and abdominal pain. Upper gastrointestinal endoscopy revealed a submucosal lesion in the posterior gastric wall. Computed tomography of the chest, abdomen and pelvis confirmed the absence of distant metastasis or enlarged lymph nodes. She underwent wide local excision with a safety margin and reconstruction. Pathologic examination of the excised mass confirmed the diagnosis of recurrent GIST. She is doing well without evidence of third recurrence or metastasis after 13 months of follow-up with a multidisciplinary team till present. GISTs are very uncommon in paediatric patients and patients should be managed in the context of a clinical trial and in tertiary centres familiar with the treatment of the disease.

Recent Progress and Challenges in the Diagnosis and Treatment of Gastrointestinal Stromal Tumors.

Simple SummaryGastrointestinal stromal tumors (GIST) are potentially malignant tumors and require evidence-based surgical and/or medical treatment. Laparoscopy has similar safety and prognostic outcomes to those of laparotomy and is currently a standard procedure for localized GISTs. However, surgery for gastric GISTs less than 2 cm may be re-evaluated due to the indolent nature of the GIST and other competing risks among GIST patients. A work-up with endoscopy and endoscopic ultrasonography as well as endoscopic or percutaneous biopsy is important for the preoperative diagnosis of GISTs. Medical treatment with tyrosine kinase inhibitors is the mainstay for recurrent/metastatic GISTs. The activity of an individual drug is well correlated with gene alterations, and, in the era of precision medicine, cancer genome profiling should be considered before medical treatment.Gastrointestinal stromal tumors (GISTs) are the most frequent malignant mesenchymal tumors in the gastrointestinal tract. The clinical incidence of GISTs is estimated 10/million/year; however, the true incidence is complicated by frequent findings of tiny GISTs, of which the natural history is unknown. The initial work-up with endoscopy and endoscopic ultrasonography plays important roles in the differential diagnosis of GISTs. Surgery is the only modality for the permanent cure of localized GISTs. In terms of safety and prognostic outcomes, laparoscopy is similar to laparotomy for GIST treatment, including tumors larger than 5 cm. GIST progression is driven by mutations in KIT or PDGFRA or by other rare gene alterations, all of which are mutually exclusive. Tyrosine kinase inhibitors (TKIs) are the standard therapy for metastatic/recurrent GISTs. Molecular alterations are the most reliable biomarkers for TKIs and for other drugs, such as NTRK inhibitors. The pathological and genetic diagnosis prior to treatment has been challenging; however, a newly developed endoscopic device may be useful for diagnosis. In the era of precision medicine, cancer genome profiling by targeted gene panel analysis may enable potential targeted therapy even for GISTs without KIT or PDGFRA mutations.

DOG1 expression is in common human tumours: a tissue microarray study on more than 15,000 tissue samples

DOG1 (Discovered on GIST1) is a voltage-gated calcium-activated chloride and bicarbonate channel that is highly expressed in interstitial cells of Cajal and in gastrointestinal stromal tumours (GIST) derived from Cajal cells. To systematically determine in what tumour entities and normal tissue types DOG1 may be further expressed, a tissue microarray (TMA) containing 15,965 samples from 121 different tumour types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. DOG1 immunostaining was found in 67 tumour types including GIST (95.7%), oesophageal squamous cell carcinoma (31.9%), pancreatic ductal adenocarcinoma (33.6%), adenocarcinoma of the papilla Vateri (20%), squamous cell carcinoma of the vulva (15.8%) and the oral cavity (15.3%), mucinous ovarian cancer (15.3%), oesophageal adenocarcinoma (12.5%), endometrioid endometrial cancer (12.1%), neuroendocrine carcinoma of the colon (11.1%) and diffuse gastric adenocarcinoma (11%). Low level-DOG1 immunostaining was seen in 17 additional tumour entities. In conclusion, our data identify several tumour entities that can show DOG1 expression levels at similar levels as in GIST. Although DOG1 is tightly linked to a diagnosis of GIST in spindle cell tumours, the differential diagnosis is much broader in DOG1 positive epithelioid neoplasms.

CT Image Examination Based on Virtual Reality Analysis in Clinical Diagnosis of Gastrointestinal Stromal Tumors.

With the advancement and development of medical equipment, CT images have become a common lung examination tool. This article mainly studies the application of CT imaging examination based on virtual reality analysis in the clinical diagnosis of gastrointestinal stromal tumors. Before extracting suspected lymph nodes from a CT image of the stomach, the CT image sequence is preprocessed first, which can reduce the cumbersomeness of subsequent extraction of suspected lymph nodes and speed up the subsequent processing. According to medical knowledge, CT images of the stomach show that lymph nodes mainly exist in the adipose tissue around the gastric wall, but there are no lymph nodes in the subcutaneous fat outside the chest. The most basic gray value in the image and the neighborhood average difference feature related to gray level are used as the primary features of visual attention detection. When extracting the neighborhood average difference feature, we use a 3∗3 sliding window method to traverse each point of the pixel matrix in the image, thereby calculating the feature value of each pixel in the image. After the feature extraction is completed, it is necessary to calibrate the data and make a training data set. The SP immunohistochemical staining method was used. The specimens were fixed with 10% formaldehyde, routinely embedded in paraffin, sectioned, and stained with HE. The tumor tissue was determined by immunohistochemistry, and the reagents were products of Maixin Company. All patients were followed up by regular outpatient review, letters, and visits or phone calls. The data showed that immunohistochemical tumor cells showed positive staining for CD117 (14/15, 93.3%) and CD34 (10/15, 66.7%). The results show that the application of virtual reality technology to CT imaging examination can significantly improve the diagnostic accuracy of gastrointestinal stromal tumors.

Germline mutations in MSH2 and ATM gene in patients with GIST (gastrointestinal stromal tumor) and second epitelial tumors.

e23520 Background: In adult GISTs are frequently sporadic, while rarely GISTs are linked to Carney Triad and Carney-Stratakis Syndrome and NF1. GISTs with second primary tumors are reported in 4-33% of patients in literature and genetic counseling is suggested to explore an underlying germline mutations pathway. Methods: In our Academic Hospital Centre (EURACAN member) in Florence, Italy, we are following patients with GIST and multiple primary tumors with genetic counseling (72 GISTs with second tumors/185 patients with GIST) and germline analysis of the following genetic panel is performed as clinically indicated: BRCA1, BRCA2, MUTYH, MLH1, MSH2, MSH6, CDH1, ATM, TP53, PTEN, CHECK2, PALB2, BARD1, BRIP1, BLM, RAD51C, RAD51D, XRCC2, PMS2, MRE11A, RAD50, NBN, FAM175A, EPKAM, TSK1, MEN1 by sequencing analysis with Illumina MiSeq by kit multiplicom BRCA Hereditary cancer Mastr plus, and bioinformatic analysis by software SOPHIADDM (Sophia genetics) for point genetic alterations of BRCA1 NM_007294.3, BRCA2 NM_000059.3, MUTYH NM_000249, MSH2 NM_000251, MSH6 NM_000179, CDH1 NM_00444360, ATM NM_000051, TP53 NM_000546, PTEN NM_000314, CHEK2 NM_001005735, PALB2 NM_024675, BARD1 NM_000465, BRIP1 NM_032043, BLM NM_000057, RAD51C NM_002876, RAD51D NM_001142571, XRCC2 NM_005431, PMS2 NM_000535, MRE11A NM_005590, RAD50 NM_006732, NBN NM_002485, FAM175A NM_139076, EPCAM NM_002354, STK1 NM_000455, MEN1 NM_000244 and MLPA (Multiplex Ligation-dependent Probe Amplification) test analysis for patients with kit P087-BRCA1,P045-BRCA2(CHEK2, P248-MLH1-MSH2, P003-MLH1/MSH2, P072-MSH6-MUTYH (MRC-Holland). Results: In 3 patients germline mutations have been observed: 1 patient showed the c.1192dupG, p.(Ala398Glyfs*19) pathogenic mutation in exon 7 of MSH2 gene, confirmed by Sanger Sequencing, 1 patient showed c.565-?_1130+?del mutation consisting in heterozygous 3-4-5-6 exons deletion of MSH2 gene, confirmed by MLPA analysis, and in 1 patient the following ATM alteration has been identified in heterozygosis: ATM c.5319+2T &gt; C, p.(?). In the 2 patients with Lynch syndrome with colon adenocarcinoma (MSI-H), synchronous GISTs (1 patient quadruple WT and 1 patient kit ex 11 mutated ) were diagnosed; in the patient with ATM mutation, the diagnosis of GIST (kit ex 11 mutated) occurred after prostate adenocarcinoma and before colon adenocarcinoma (MSI-H). Conclusions: Our analysis suggests that GIST diagnosis could be tumor-related to multiple hereditary tumor syndromes as Lynch Syndrome and Ataxia-Teleangectasia syndrome, the latter being linked in eterozygosis to tumor susceptibility to breast in female. This report represents a high value in terms of genetic counseling for relatives and in terms of therapeutic implications for the patients.

Second Primary Tumors in Patients with Gastrointestinal Stromal Tumors: A Single-Center Experience.

Background and Objectives: In this study, we investigated the frequency and type of second primary malignant tumors (SPMTs) accompanying gastrointestinal stromal tumors (GISTs), patient and tumor characteristics, and follow-up and survival data. Materials and Methods: We included 20 patients with SPMTs from a total of 103 patients with GISTs in a single center in Turkey. At the time of GIST diagnosis, patient age, sex, presentation symptoms, localization, pathological features of the tumor, stage, recurrence risk scoring for localized disease, treatments received, time of SPMT association, follow-up times, and survival analysis were recorded for each patient. Localization, histopathology, and stage of SPMT accompanying GISTs were also recorded accordingly. Results: SPMT was detected in 19.4% of patients with GISTs. Of the patients, 50% were men and 50% were women. The mean age at the time of diagnosis of GIST was 63.8 ± 10.81 years (range: 39–77 years). Of the GISTs, 60% were localized in the stomach, 25% in the small intestine, and 70% were at low risk. Of the SPMTs, 60% were in the gastrointestinal system. SPMTs were diagnosed as synchronous with GISTs in 50% of the patients. The mean follow-up period of the patients from the diagnosis of GIST was 45.6 (0.43–129.6) months. When the data were finalized, 5% died due to GIST, 35% died due to SPMT, and 15% died due to non-disease-related causes. Conclusions: SPMT was detected in 19.4% of patients with GISTs. GISTs were frequently located in the stomach, and most of them were at low risk. The most common SPMTs were gastrointestinal system tumors, and their coexistence was found to be synchronous. Most patients died due to SPMT during follow-up.

Jejunal GIST masquerading as an ovarian mass: A case report.

Introduction and importanceGastrointestinal stromal tumors (GIST) are rare mesenchymal tumors originating in the wall of the gastrointestinal tract. Jejunal GIST is the rarest subtype. Large GIST can present with an abdominopelvic mass which can be preoperatively misdiagnosed as a gynecological tumor.Case historyA 44-year regularly menstruating woman presented with lower abdominal pain which was diagnosed as a malignant ovarian tumor preoperatively with an MRI. However, intraoperatively, a lobulated mass was present in the abdominal cavity arising from a jejunal portion of the small intestine. With an intraoperative diagnosis of jejunal GIST, the mass was excised and jejunum anastomosed. Histopathology examination report showed GIST which was further confirmed by immunohistochemistry.DiscussionGIST presenting as a large abdominopelvic mass can mimic a gynecological tumor. Contrast-enhanced CT scan is the preferred imaging modality for the evaluation of patients with suspected GIST to determine the extent of the tumor, the presence or absence of metastatic disease alongside evaluation of the possibility of complete resection. Adjuvant imatinib therapy following complete excision can decrease the disease recurrence.ConclusionGynecologists should keep in mind that primary gastrointestinal tumors can present as a pelvic mass. A proper histopathological examination helps to confirm the diagnosis. Complete surgical removal of the tumor should be obtained as it determines the prognosis of the disease.

Gastric GIST with progressive mitotic index

Gastrointestinal stromal tumors (GISTs) account for less than 1% of gastrointestinal tumors;they are the most common mesenchymal neoplasms of the gastrointestinal(GI) tract. GISTs are usually located in the stomach,but can occur anywhere along the gastrointestinal tract.GIST ranks third as histology after adenocarcinomas and lymphomas among the gastrointestinal tract.Case presentation.The patient, aged 58 years, is transferred from the Gastroenterology Clinic with symptoms of stenosis and hemorrhage from a endophytic submucosal tumor located on the posterior gastric wall, under the eso-gastric junction, objectified endoscopically and CT scan. Laparoscopic wedge resection was performed with three linear Endo-GIA staplers. The evolution was favorable. After 7 months (without chemotherapy because pTNM was T1NoMo), the patient is sent back by the gastroenterologist for „CT scan:perigastric lymphadenopathies”. The patient was operated laparoscopically converted.We found 10 tumors with typical malignant GISTs 3-10 cm diameter,on the peritoneal serosa:in the right subhepatic space, perigastric, left interhepato-phrenic, hepato-gastric;these were excised R0; with simple evolution. The immuno-histo-chemical examination specifies the diagnosis of GIST at the first and the second operation (DOG1,CD117,CD34-positively in tumor).Ki 67 was 15% in the tumor and the mitotic index &lt;5/5 square mm at the moment of the first operation but in the metastatic tumor at the reintervention Ki 67 was 80% and mitotic index &gt;5/5 square mm.Discutions.GIST tumours can be classified into low-risk and high-risk categories of recurrence depending on size, location, capsule rupture and mitotic activity. Disseminated metastases in the abdominal cavity are the most common clinical manifestations of malignancy. Complete surgical resection is recommended if bleeding or other symptoms are present. Tumour perforation, spontaneous or produced at the time of surgical resection, should be recorded because it has a high negative prognostic value due to peritoneal contamination. The average survival rate in localized disease is 5 years but in metastatic or recurrent disease is about 10-20 months. Conclusion. Complete excision of residual metastatic lesions has been shown to be associated with a favourable prognosis, provided that the patient responds to imatinib treatment; resection of tumour recurrence is accompanied by an average survival of 15 months. Gastric GIST recurrence risk depends of localisation, tumor size, mitotic index and capsular rupture.

5-aminolaevulinic acid (5-ALA) accumulates in GIST-T1 cells and photodynamic diagnosis using 5-ALA identifies gastrointestinal stromal tumors (GISTs) in xenograft tumor models.

Gastrointestinal stromal tumor (GIST) diagnosis using conventional gastrointestinal endoscopy is difficult because such malignancies cannot be distinguished from other types of submucosal tumors. Photodynamic diagnosis (PDD) is based on the preferential uptake of photosensitizers by tumor tissues and its detection by fluorescence emission upon laser excitation. In this study, we investigated whether PDD using 5-aminolevulinic acid (5-ALA), a standard photosensitizer used worldwide, could be used for GIST diagnosis. 5-ALA is metabolized to endogenous fluorescent protoporphyrin IX (PpIX). We examined the accumulation of PpIX in GIST-T1 cells using flow cytometry and immunofluorescent staining. Furthermore, we established GIST-T1 xenograft mouse models and examined PpIX accumulation in the resultant tumors. PpIX accumulated in GIST-T1 cells and was localized mainly to lysosomes. PpIX accumulation was also observed in murine xenograft tumors. Moreover, tumor and normal tissues could be distinctly identified by relative PpIX fluorescence. Thus, our results demonstrated that PDD with 5-ALA has substantial clinical potential for GIST diagnosis.