Gastrointestinal Stromal Tumors of the Stomach: Is There Any Advantage of Robotic Resections? A Systematic Review and Meta-Analysis.

Background: The role of robotic surgery for gastrointestinal stromal tumor (GIST) resection remains unclear. This systematic review and meta-analysis aimed to investigate the outcomes of robotic versus laparoscopic surgery in patients requiring surgery for gastric GISTs. Methods: MEDLINE, EMBASE, and the Cochrane databases were searched from inception to September 4, 2023. Two independent reviewers conducted a systematic review of the literature to select all types of analytic studies comparing robotic versus laparoscopic surgery for GISTs and reporting intraoperative, postoperative, and/or pathological outcomes. Results: Overall, 4 retrospective studies were selected, including a total of 264 patients, specifically 111 (42%) in the robotic and 153 (58%) in the laparoscopic group. Robotic surgery was associated with longer operating time (+42.46 min; 95% confidence interval [CI]: 9.34, 75.58; P=0.01; I2: 85%) and reduced use of mechanical staplers (odds ratio [OR]: 0.05; 95%CI: 0.02, 0.11; P<0.00001; I2: 92%;) compared with laparoscopy. Although nonsignificant, conversion to open surgery was less frequently reported for robotic surgery (2.7%) than laparoscopy (5.2%) (OR: 0.59; 95%CI: 0.17, 2.03; P=0.4; I2: 0%). No difference was found for postoperative and oncological outcomes. Conclusions: Robotic surgery for gastric GISTs provides similar intraoperative, postoperative, and pathological outcomes to laparoscopy, despite longer operative time.

Utilization of Neoadjuvant Therapy for Localized Gastric Gastrointestinal Stromal Tumors and the Association with Survival.

BACKGROUND: For gastric GISTs, neoadjuvant imatinib is most often reserved for tumors near the gastroesophageal junction, multi-visceral involvement, or limited metastatic disease. Whether localized gastric GISTs benefit from neoadjuvant therapy (NAT) remains unknown. We sought to examine factors associated with NAT utilization for localized gastric GISTs and evaluate implications on survival. METHODS: The National Cancer Database identified patients with localized gastric GISTs treated with NAT (2010-2020), excluding tumors extending beyond the gastric wall, located in the cardia, or with metastatic disease. Multivariable logistic regression assessed characteristics of NAT use. After 1:1 propensity score matching, Kaplan-Meier methods and multivariable Cox regression assessed overall survival (OS). RESULTS: Of 7,203 patients, 762 (10.6%) received NAT followed by resection. On multivariable analysis, increasing tumor size was associated with NAT use (<2.0cm vs 2.0-5.0cm OR:2.03, 95%CI 1.19-3.47, p=0.010; vs >5cm OR:16.87, 95%CI 10.02-28.40, p<0.001). After propensity score matching, 1,506 patients remained. Median OS for NAT was 46.0 months vs 43.0 months for resection (p=0.059) which was independently predictive of improved survival (HR:0.89; 95%CI 0.80-0.99, p=0.041). Subgroup analysis by tumor size showed no survival differences for tumors <2.0cm or 2.0-5.0cm. Median OS was higher for tumors >5.0cm treated with NAT (NAT:45.4 months [IQR 29.5-65.9]. vs upfront resection:42.3 months [26.9-62.8]) and associated with improved survival on multivariable analysis (HR:0.88; 95%CI 0.78-0.99, p=0.040). CONCLUSION: Although patients who received NAT had improved survival, this was primarily due to tumors >5.0cm. Expanding NAT selection criteria to include localized gastric GISTs >5.0cm may improve outcomes and warrants investigation through clinical trials.

Manipulated overlapping reactivation of multiple memories promotes explicit gist abstraction.

Sleep is considered to promote gist abstraction on the basis of spontaneous memory reactivation. As speculated in the theory of 'information overlap to abstract (iOtA)', 'overlap' between reactivated memories, beyond reactivation, is crucial to gist abstraction. Yet so far, empirical research has not tested this theory by manipulating the factor of 'overlap'. In the current study, 'overlap' itself was manipulated by targeted memory reactivation (TMR), through simultaneously reactivating multiple memories that either contain or do not contain spatially overlapped gist information, to investigate the effect of overlapping reactivation on gist abstraction. This study had a factorial design of 2 factors with 2 levels respectively (spatial overlap/no spatial overlap, TMR/no-TMR). Accordingly, 82 healthy college students (aged 19 ∼ 25, 57 females) were randomized into four groups. After learning 16 pictures, paired with 4 auditory cues (4 pictures - 1 cue) according to the grouping, participants were given a 90-minute nap opportunity. Then TMR cueing was conducted during N2 and slow wave sleep of the nap. Performance in memory task was used to measure gist abstraction. The results showed a significant main effect of TMR on both implicit and explicit gist abstraction, and a marginally significant interaction effect on explicit gist abstraction. Further analyses showed that explicit gist abstraction in the spatial overlap & TMR group was significantly better than in the control group. Moreover, explicit gist abstraction was positively correlated with spindle density. The current study thus indicates that TMR facilitates gist abstraction, and explicit gist abstraction may benefit more from overlapping reactivation.

A Gastrointestinal Stromal Tumor (GIST) and a Pseudocyst of the Pancreas: A Peculiar Case of Both Co-existing in the Same Patient.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal (GI) tract, typically originating from the interstitial cells of Cajal. The clinical presentations are variable according to their size and shape but rarely present as a palpable abdominal mass. Pancreatic pseudocysts are common complications of chronic pancreatitis characterized by fluid collections surrounded by a non-epithelialized wall of fibrous and granulation tissue. Patients may present with non-specific symptoms like abdominal pain, nausea, and vomiting and they generally have a history of acute pancreatitis. Small pseudocysts often resolve spontaneously, but larger ones often become symptomatic and may lead to complications. It is rare to find both a GIST of the stomach and a pseudocyst of the pancreas in the same patient. We present a unique case of a giant GIST and a pancreatic pseudocyst in a 72-year-old male who was experiencing abdominal pain and distension. Imaging revealed a massive lesion originating from the posterior gastric wall, which resembled a pseudocyst, along with a distinct cystic lesion adjacent to the pancreatic body. During surgical exploration, a complex interplay of both pathologies was discovered, requiring a comprehensive resection approach. The successful outcome highlights the importance of careful evaluation and personalized management in such rare cases.

A diagnostic challenge of KIT p.V559D and BRAF p.G469A mutations in a paragastric mass.

A patient with gastrointestinal stroma tumor (GIST) and KIT p.V559D and BRAF p.G469A alterations was referred to our institutional molecular tumor board (MTB) to discuss therapeutic implications. The patient had been diagnosed with B-cell chronic lymphocytic leukemia (CLL) years prior to the MTB presentation. GIST had been diagnosed 1 month earlier. After structured clinical annotation of the molecular alterations and interdisciplinary discussion, we considered BRAF/KIT co-mutation unlikely in a treatment-naïve GIST. Discordant variant allele frequencies furthermore suggested a second malignancy. NGS of a CLL sample revealed the identical class 2 BRAF alteration, thus supporting admixture of CLL cells in the paragastric mass, leading to the detection of 2 alterations. Following the MTB recommendation, the patient received imatinib and had a radiographic response. Structured annotation and interdisciplinary discussion in specialized tumor boards facilitate the clinical management of complex molecular findings. Coexisting malignancies and clonal hematopoiesis warrant consideration in case of complex and uncommon molecular findings.

A Rare Case of Colonic Gastrointestinal Stromal Tumor.

Gastrointestinal stromal tumors (GISTs) are a type of mesenchymal tumor of the gastrointestinal tract that originate anywhere in the gastrointestinal tract, with the colon and appendix being the least recorded sites of occurrence. The following case report is that of a colonic GIST in a 53-year-old male and its histologic type. Included are notes on the recent additions and updates in the risk stratification of GISTs occurring in unusual sites with the relevant immunohistochemistry.

The effect of temporal context on memory for art.

Although considerable research has been done on memory for temporal information, as well as on the relationship between context and cognition, not much is known about the influence of temporal context on memory formation and retention. In this study, given that our sample comes from a largely Roman Catholic population, we used religious practices that occur throughout the calendar year to operationalize temporal context into two religious seasons (Lent and Ordinary Time). In addition, we used religious art to assess experience and memory as a function of whether there was temporal congruity or incongruity. This allowed us to explore different levels of memory representation; namely, memory for perceptual details of the art, memory for more inferential understanding of the art, and autobiographical memory for the initial experience of the art. Participants viewed 22 representational and abstract artworks during either Lent or Ordinary Time. After viewing, memory was tested at immediate, 1-day, and 7-day delays. We expected that the congruent temporal context (i.e., Lent) would lead to more activated semantic knowledge, which would then aid memory encoding and retention. This was the case only for perceptual details of the art. In addition, during Lent, forgetting followed a more linear pattern. These results suggest that priming semantic knowledge through temporal context leads encoding to focus on low-level information, as opposed to the processing of more complex information. Overall, these findings suggest that temporal context can influence cognition, but to a limited extent.

Acute abdomen due to perforated jejunal gastrointestinal stromal tumor: A case report.

INTRODUCTION: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors, with jejunal GISTs being particularly uncommon. Jejunal GISTs causing perforation and acute diffuse peritonitis is rare. CASE PRESENTATION: A 53-year-old female with a history of hypertension presented with severe, acute abdominal pain and vomiting. Examination revealed abdominal distension, tenderness, and guarding, with imaging suggestive of gastrointestinal perforation. Emergency laparotomy revealed a 9 cm × 8 cm mass with perforation in the jejunum, which was resected which on histopathological examination confirmed a low-grade GIST. The postoperative course was complicated by a wound infection, managed with antibiotics and secondary suturing. At one-year follow-up, the patient remained disease-free without the need for adjuvant therapy. CLINICAL DISCUSSION: The most common symptoms of jejunal GISTs include vague abdominal pain or discomfort, early satiety, obstruction or hemorrhage. Preoperative diagnosis and confirmation of GIST is difficult due to nonspecific symptoms and none of the radiographic procedures can establish the diagnosis with certainty. The surgical excision of the tumor along with infiltrated tissues is the treatment of choice for GIST. CONCLUSION: This case underscores the necessity of considering GISTs in differential diagnoses of acute abdomen and the critical role of prompt surgical management and multidisciplinary care in achieving favorable outcomes.

An ultrasound based method for predicting the malignant potential of primary gastrointestinal stromal tumors preoperatively.

OBJECTIVE: Gastrointestinal stromal tumors (GISTs) are difficult to identify the risk level accurately without surgical pathological confirmation. The purpose of our study was to propose a noninvasive prediction method for predicting the malignant potential of GISTs preoperatively by using contrast-enhanced ultrasound (CEUS) with gastric distention. METHODS: We reviewed 47 GISTs who underwent CEUS from April 2017 to August 2023 retrospectively, all the lesions were certificated by pathology after surgery. The age of the patient, size of the lesion, shape, necrosis, calcification in the lesion, perfusion parameters including arrival time (AT), peak intensity (PI), time to peak (TTP), and area under the curve (AUC) of the lesion and surrounding normal tissue were analyzed. Logistic regression analyses were performed. Of the 47 GISTs, 26 were high-risk and 21 low-risk tumors respectively. RESULTS: Compared with low-risk GISTs, high-risk GIST had faster AT (7.7s vs. 11.5s, p < 0.05), higher PI (15.2dB vs. 12.5dB, p < 0.05), and larger size (4.4 cm vs. 2.2 cm, p < 0.001). In multivariate logistic regression, AT, PI, and size were significant features. The corresponding regression equation In (p/(1-p)=-5.9 + 4.5 size + 4.6 PI + 4.0 AT). CONCLUSION: The size, AT, and PI of the GISTs on CEUS can be used as parameters for a noninvasive risk level prediction model of GISTs. This model may help identify the different risk levels of GISTs before surgery.

Pilot Study by Liquid Biopsy in Gastrointestinal Stromal Tumors: Analysis of PDGFRA D842V Mutation and Hypermethylation of SEPT9 Presence by Digital Droplet PCR.

Tissue biopsy remains the standard for diagnosing gastrointestinal stromal tumors (GISTs), although liquid biopsy is emerging as a promising alternative in oncology. In this pilot study, we advocate for droplet digital PCR (ddPCR) to diagnose GIST in tissue samples and explore its potential for early diagnosis via liquid biopsy, focusing on the PDGFRA D842V mutation and SEPT9 hypermethylated gene. We utilized ddPCR to analyze the predominant PDGFRA mutation (D842V) in surgical tissue samples from 15 GIST patients, correlating with pathologists' diagnoses. We expanded our analysis to plasma samples to compare DNA alterations between tumor tissue and plasma, also investigating SEPT9 gene hypermethylation. We successfully detected the PDGFRA D842V mutation in GIST tissues by ddPCR. Despite various protocols to enhance mutation detection in early-stage disease, it remained challenging, likely due to the low concentration of DNA in plasma samples. Additionally, the results of Area Under the Curve (AUC) for the hypermethylated SEPT9 gene, analyzing concentration, ratio, and abundance were 0.74 (95% Confidence Interval (CI): 0.52 to 0.97), 0.77 (95% CI: 0.56 to 0.98), and 0.79 (95% CI: 0.59 to 0.99), respectively. As a rare disease, the early detection of GIST through such biomarkers is particularly crucial, offering significant potential to improve patient outcomes.

Endoscopic resection for esophageal gastrointestinal stromal tumors: a multi-center feasibility study.

Background: Esophageal gastrointestinal stromal tumors (E-GISTs) are highly uncommon and have not been thoroughly examined. Objectives: The objective of this multi-center study was to assess the viability of endoscopic resection (ER) in the treatment of E-GISTs and to explore its clinical implications. Design: This was a multi-center retrospective study. Consecutive patients referred to the four participating centers. Methods: E-GISTs among the consecutive subepithelial tumors (SETs) treated by ER methods were enrolled from April 2019 to August 2022. Clinicopathological, endoscopic, and follow-up data were collected and analyzed. Results: A total of 23 patients with E-GISTs were included for analysis, accounting for 1.9% of all the esophageal SETs (1243 patients). The average size of the tumor lesions was 2.3 cm (range 1.0-4.0 cm). We observed that tumors larger than 2.0 cm were more likely to grow deeper, with a statistically significant difference (p < 0.001). End bloc resection was achieved in all 23 patients. The mean operation time was 53.6 min (range 25-111 min). One patient experienced significant intraoperative bleeding, which was promptly managed endoscopically without necessitating surgery. The average hospital stay was 4.5 days (range 3-8 days). The overall median follow-up period was 31 months (range 13-47 months). No tumor recurrence, residual tumor, distal metastasis, or death was observed during the follow-up period. Conclusion: Based on our limited data, our study indicates that ER may be a feasible and effective option for treating esophageal GISTs measuring 4 cm or less. We suggest submucosal tunnel endoscopic resection as the preferred approach, as all E-GISTs in our study were situated in the muscularis propria layer. Additionally, tumors larger than 2 cm were more prone to deeper growth or extraluminal extension.

Gastrointestinal Stromal Tumour of the Appendix: A Very Rare Entity.

A 74-year-old man who presented with upper abdominal pain was found to have an incidental appendiceal mass on cross-sectional imaging. He underwent a laparoscopic appendicectomy with histopathological examination confirming a completely resected appendiceal gastrointestinal stromal tumour (GIST). Appendiceal GISTs are rare. Therefore, there is limited evidence to guide risk stratification and management with extrapolation of prognosis from data on GISTs at other sites. This paper highlights the rarity of these tumours and presents another case which correlates well with the existing but limited literature. There is a need to maintain a registry of this rare disease entity with the maintenance of longer-term follow-up data.

Gastrointestinal stromal tumor of the duodenum presenting with shock and massive upper and lower gastrointestinal bleeding: a case report and review of the literature.

BACKGROUND: Due to rarity of duodenal GISTs, clinicians have few information about its clinical features, diagnosis, management and prognosis. CASE REPORT: We report a case of promptly diagnosed duodenal GIST in a 61-year-old Egyptian man presented shocked with severe attack of hematemesis and melena. Upper gastroduodenal endoscopy was done and revealed a large ulcerating bleeding mass at first part of duodenum 4 hemo-clips were applied with good hemostasis. An exploratory laparotomy and distal gastrectomy, duodenectomy and gastrojejunostomy were performed. The morphology of the mass combined with immunohistochemistry was consistent with duodenal gastrointestinal stromal tumours (GISTs) of high risk type. The patient is on amatinib one tablet daily and he was well with no evidence of tumor recurrence. CONCLUSION: despite being rare, emergency presentation with sudden severe, life-threatening hemorrhagic shock duodenal GISTs might be a cause of potentially lethal massive combined upper and lower gastrointestinal bleeding which is the key feature of this rare and challenging tumor.

Working memory limitations constrain visual episodic long-term memory at both specific and gist levels of representation.

Limitations in one's capacity to encode information in working memory (WM) constrain later access to that information in long-term memory (LTM). The present study examined whether these WM constraints on episodic LTM are limited to specific representations of past episodes or also extend to gist representations. Across three experiments, young adult participants (n = 40 per experiment) studied objects in set sizes of two or six items, either sequentially (Experiments 1a and 1b) or simultaneously (Experiment 2). They then completed old/new recognition tests immediately after each sequence (WM tests). After a long study phase, participants completed LTM conjoint recognition tests, featuring old but untested items from the WM phase, lures that were similar to studied items at gist but not specific levels of representation, and new items unrelated to studied items at both specific and gist levels of representation. Results showed that LTM estimates of specific and gist memory representations from a multinomial-processing-tree model were reduced for items encoded under supra-capacity set sizes (six items) relative to within-capacity set sizes (two items). These results suggest that WM encoding capacity limitations constrain episodic LTM at both specific and gist levels of representation, at least for visual objects. The ability to retrieve from LTM each type of representation for a visual item is contingent on the degree to which the item could be encoded in WM.

Gastric Schwannoma in an Octogenarian: A Case Report and Review of the Literature.

Gastric schwannomas are an exceedingly rare tumor arising from the myenteric plexus of the gastrointestinal enteric nervous system. These schwannomas are most commonly benign and reported to occur in female patients with a mean age of 58 at presentation. They are most often discovered incidentally, but can occasionally present with abdominal discomfort, obstructive symptoms, or GI bleeding. Frequently, the initial clinical consideration is for a gastrointestinal stromal tumor, which is much more common. A definitive diagnosis is made with microscopic imaging and immunohistochemical staining. Complete surgical resection, typically performed laparoscopically, is the most definitive and usually curative treatment, requiring no further follow-up. Herein, we present the first and only case of gastric schwannoma in an octogenarian and discuss an update on current diagnostic and therapeutic options.

Metachronous Gastrointestinal Stromal Tumors of Different Histologies: An Unusual Case.

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors accounting for only a small fraction of all primary malignant tumors of the gastrointestinal tract. Histologically, GISTs are classified as epithelioid, spindle type, or mixed. We present a case of a 66-year-old male incidentally noted to have a pedunculated gastric mass along the lesser curvature of the stomach during a laparoscopic Nissen fundoplication and hiatal hernia repair. A wedge resection was performed and the pathology demonstrated a 3.7 cm GIST of epithelioid type. Four years after the initial surgery, a jejunal mass was identified via CT enterography as part of a workup for ongoing iron deficiency anemia. A laparoscopic small bowel resection was performed, and the pathology revealed a new primary 3.2 cm GIST of the spindle cell subtype. Three years after surgery, surveillance imaging is negative for any recurrence. This appears to be the first report of the occurrence of metachronous primary GISTs of different histologic subtypes, separated by location.

Arbutus unedo L. Fractions Exhibit Chemotherapeutic Properties for the Treatment of Gastrointestinal Stromal Tumors.

Novel treatments in gastrointestinal stromal tumors (GISTs) are essential due to imatinib resistance and the modest results obtained with multi-target tyrosine kinase inhibitors. We investigated the possibility that the hydroalcoholic extract from the leaves of Arbutus unedo L. (AUN) could harbor novel chemotherapeutics. The bio-guided fractionation of AUN led to a subfraction, FR2-A, that affected the viability of both imatinib-sensitive and -resistant GIST cells. Cells treated with FR2-A were positive for Annexin V staining, a marker of apoptosis. A rapid PARP-1 downregulation was observed, although without the traditional caspase-dependent cleavage. The fractionation of FR2-A produced nine further active subfractions (FRs), indicating that different molecules contributed to the effect promoted by FR2-A. NMR analysis revealed that pyrogallol-bearing compounds, such as gallic acid, gallic acid hexoside, gallocatechin, myricetin hexoside, and trigalloyl-glucose, are the main components of active FRs. Notably, FRs similarly impaired the viability of GIST cells and peripheral blood mononuclear cells (PBMCs), suggesting a non-specific mechanism of action. Nevertheless, despite the lack of specificity, the established FRs showed promising chemotherapeutic properties to broadly affect the viability of GIST cells, including those that are imatinib-resistant, encouraging further studies to investigate whether pyrogallol-bearing compounds could represent an alternative avenue in GISTs.

Life-threatening gastrointestinal bleeding in a case of neurofibromatosis 1 and gastrointestinal stromal tumour managed with surgical intervention as a case report.

A 63-year-old patient with skin neurofibromas since birth was brought to emergency in a critical state due to massive bleeding per rectum. After stabilization and massive transfusion, the patient underwent Gastro-Intestinal (GI) endoscopy and abdominal computed tomography. A mass was identified in the jejunum. On laparotomy, multiple neurofibromas were seen in the jejunum. The segment with bleeding tumour was resected. Histopathology revealed benign spindle cell neoplasm, a gastrointestinal stromal tumour. The patient recovered and was discharged on day 15.

Exploring Gastric Perforation as an Uncommon yet Critical Complication of Gastrointestinal Stromal Tumors.

Hollow viscus perforation poses a significant diagnostic and therapeutic dilemma for the majority of clinicians. It is vitally important that in cases of gastrointestinal perforation, the tissue that was perforated is always evaluated, since a malignant tumor can cause this complication as a presentation form. Here, we present the case of a patient whose first manifestation of a malignant gastric tumor was its perforation and the presence of septic shock secondary to this. This case exemplifies the importance of innovative thinking in facilitating a comprehensive diagnostic and therapeutic strategy, leading to the timely identification and management of a malignant tumor by the oncology team; such interventions not only enhance patient outcomes but also mitigate morbidity and mortality rates.

Intracystic gastrointestinal stromal tumor developed in the round ligament of the liver.

A 44-year-old woman was referred to our hospital for the examination and treatment of a presumed gallbladder tumor. Both ultrasound and computed tomography showed an intracystic tumor but failed to point out the discontinuity between the cystic lesion and the gallbladder. Magnetic resonance imaging, however, could clearly depict the presumed intracystic tumor and the discontinuity between the gallbladder and the target lesion. Both contents of the gallbladder and the cystic lesion showed hypo and hyper intense patterns, though both with slightly different intensities, on T1- and T2-weighted images, respectively. Under the preoperative diagnosis of early gallbladder cancer despite these image findings, laparoscopic cholecystectomy was attempted to the patient. Laparoscopic observation, however, revealed that the target lesion was not continuous with the gallbladder and was located in the round ligament of the liver. Intraoperative findings led us to do cholecystectomy and resection of the adjacent cystic tumor. The intracystic tumor was 3 cm in size and had minute solid component inside the cyst wall. Pathological study of the presumed gallbladder cancer showed epithelioid cells and spindle cells growing in sheet like and storiform fashions, respectively. Cystic walls mainly consisted of hypo cellular fibrous components. Immunohistochemical staining of the tumor was positive for CD117 and negative both for desmin and S100, leading to the diagnosis of gastrointestinal stromal tumor. MIB-1 labelling index of the gastrointestinal stromal tumor was 8%. The patient recovered uneventfully and has been well without any recurrences for 3 months.