Gastrointestinal Stromal Tumors

Survival of advanced/recurrent gastrointestinal stromal tumors treated with tyrosine kinase inhibitors in Taiwan: a nationwide registry study

BACKGROUND

Most gastrointestinal stromal tumors (GISTs) harbor c-KIT or PDGFRA mutations. Administration of tyrosine kinase inhibitors (TKIs) has significantly improved the survival of patients with GISTs. We aimed to evaluate the clinical outcome of advanced or recurrent GIST patients in Taiwan.

METHODS

Patients diagnosed between 2010 and 2020 were enrolled. The collected data included baseline characteristics, treatment pattern, treatment outcome, genetic aberrations and survival status. Progression-free survival (PFS) and overall survival (OS) were analyzed and plotted with the Kaplan-Meier method. Cox regression analysis was used to analyze the prognostic factors of survival.

RESULTS

A total of 224 patients with advanced or recurrent GISTs treated with TKIs were enrolled. All patients received imatinib treatment. Ninety-three and 42 patients received sunitinib and regorafenib treatment, respectively. The 48-month PFS and OS rates for patients treated with imatinib were 50.5% and 79.5%, respectively. c-KIT exon 9 and PDGFRA mutations were prognostic factors for a poor PFS and PDGFRA mutation was a prognostic factor for a poor OS in patients treated with imatinib in multivariate Cox regression analysis. The median PFS of patients who received sunitinib treatment was 12.76 months (95% confidence interval (CI), 11.01-14.52). Patients with c-KIT exon 9 mutations had a longer PFS than those with other genetic aberrations. The median PFS of patients treated with regorafenib was 7.14 months (95% CI, 3.39-10.89).

CONCLUSIONS

We present real-world clinical outcomes for advanced GIST patients treated with TKIs and identify mutational status as an independent prognostic factor for patient survival.

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.

Clinical course of small gastric subepithelial lesion less than 20 mm diagnosed by endoscopic ultrasound-guided fine-needle aspiration

BACKGROUND AND AIM

Gastrointestinal stromal tumors (GISTs) are treated as malignant gastric subepithelial lesions (SELs), and resection is recommended. However, small gastric SELs < 20 mm with no malignant features are monitored without histopathological examination, and the frequency of malignancy is unknown. This study aimed to clarify the clinicopathological findings and clinical course of gastric SELs < 20 mm measured by endoscopic ultrasound (EUS).

METHODS

This retrospective cohort study included consecutive patients with small gastric SELs < 20 mm diagnosed using EUS at a tertiary referral center between 2009 and 2021. The clinical course after diagnosis using EUS-guided fine-needle aspiration (EUS-FNA) was reviewed.

RESULTS

Among 333 patients with small gastric SELs, 104 patients with 105 lesions underwent EUS-FNA. The pathological diagnosis was confirmed in 87 patients. GISTs were the most common pathology (47%). Among the 87 patients, 43 underwent therapeutic interventions, including tumor resection and chemotherapy. In groups of tumor resection, the pathological tumor size on the resected specimen was significantly larger than the size measured by EUS (19.5 mm vs 15.0 mm, P < 0.001), and 37% of resected SELs were 20 mm or over. No recurrence was observed after tumor resection during a mean follow-up period of 40 months.

CONCLUSIONS

Approximately 40% of small gastric SELs were malignant tumors, such as GIST, with most of them requiring treatment. Additionally, considering that the EUS measurement is 5 mm smaller than the pathological tumor diameter, further examinations, such as systematic EUS-FNA, may be required for SEL, including those smaller than 20 mm.

The impact of gender on survival outcomes in patients with small intestinal stromal tumors: a comprehensive analysis using the SEER database

BACKGROUND

Small intestinal stromal tumors (SISTs) are a rare type of mesenchymal tumor. Gender is known to influence the incidence and prognosis of various tumors, but its role on the survival of SISTs at the population level remains unclear. Therefore, we aim to explore the relationship between gender and the prognosis of SISTs using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Data on SISTs patients from 2000 to 2019 were derived from the SEER database. Multiple imputation was used to address missing data. Kaplan-Meier analyses and Cox proportional hazard models were applied to evaluate the impact of demographic and clinical characteristics on overall survival (OS) and cancer-specific survival (CSS).

RESULTS

A total of 3513 patients with SISTs were analyzed, including 1921 males and 1592 females. Kaplan-Meier analysis coupled with log-rank testing demonstrated a significantly higher mortality rate among male patients compared to females (P < 0.001). Notably, female patients exhibited superior OS (hazard ratio [HR] 0.808, 95% confidence interval [CI] 0.724-0.902, P < 0.001) and CSS (HR 0.801, 95% CI 0.692-0.927, P = 0.003) compared to male patients. While the mean 1-year CSS rates were comparable between genders (95.3% for males vs. 96.0% for females, P = 0.332), male patients consistently showed lower mean survival rates at 3-, 5-, and 10-year intervals. Surgical intervention significantly boosted 5-year OS and CSS rates in both male and female patients (P < 0.001). Multivariate Cox regression analysis identified age, sex, grade, TNM stage, surgery, and mitotic rate as independent risk factors for OS and CSS in patients with SISTs.

CONCLUSIONS

Our findings suggest that male patients with SISTs have a higher risk of mortality compared to female patients, indicating that gender may serve as a predictive indicator for survival in this patient population.

Automated machine learning for predicting liver metastasis in patients with gastrointestinal stromal tumor: a SEER-based analysis

Gastrointestinal stromal tumors (GISTs) are a rare type of tumor that can develop liver metastasis (LIM), significantly impacting the patient's prognosis. This study aimed to predict LIM in GIST patients by constructing machine learning (ML) algorithms to assist clinicians in the decision-making process for treatment. Retrospective analysis was performed using the Surveillance, Epidemiology, and End Results (SEER) database, and cases from 2010 to 2015 were assigned to the developing sets, while cases from 2016 to 2017 were assigned to the testing set. Missing values were addressed using the multiple imputation technique. Four algorithms were utilized to construct the models, comprising traditional logistic regression (LR) and automated machine learning (AutoML) analysis such as gradient boost machine (GBM), deep neural net (DL), and generalized linear model (GLM). We evaluated the models' performance using LR-based metrics, including the area under the receiver operating characteristic curve (AUC), calibration curve, and decision curve analysis (DCA), as well as AutoML-based metrics, such as feature importance, SHapley Additive exPlanation (SHAP) Plots, and Local Interpretable Model Agnostic Explanation (LIME). A total of 6207 patients were included in this study, with 2683, 1780, and 1744 patients allocated to the training, validation, and test sets, respectively. Among the different models evaluated, the GBM model demonstrated the highest performance in the training, validation, and test cohorts, with respective AUC values of 0.805, 0.780, and 0.795. Furthermore, the GBM model outperformed other AutoML models in terms of accuracy, achieving 0.747, 0.700, and 0.706 in the training, validation, and test cohorts, respectively. Additionally, the study revealed that tumor size and tumor location were the most significant predictors influencing the AutoML model's ability to accurately predict LIM. The AutoML model utilizing the GBM algorithm for GIST patients can effectively predict the risk of LIM and provide clinicians with a reference for developing individualized treatment plans.

An Extragastrointestinal Stromal Tumor Arising From the Omentum in a Young Hispanic Male

Gastrointestinal stromal tumors (GISTs) are neoplasms arising from the bowel wall, most often in the jejunoileum of the small intestine, but rarely from extragastrointestinal locations. GISTs most often occur in patients older than 40 years of age and can present with a multitude of gastrointestinal symptoms. We present a rare case of an extragastrointestinal stromal tumor (EGIST) causing abdominal pain and melena in a 34-year-old Hispanic male. The patient presented with diffuse abdominal pain, melena, and severe anemia. Computed tomography of the abdomen revealed a large mass abutting the small bowel. The patient was taken to surgery where the mass, which appeared to be deriving from the omentum and invading the adjacent small bowel, was completely excised and found to be a spindle cell GIST. Excision margins were determined to be negative, and the patient was started on a tyrosine kinase inhibitor for maintenance therapy. The patient continues to follow up on an outpatient basis for surveillance. This case represents the rare disease entity EGIST presenting outside the typical demographics of the disease in a young patient with no identified previous genetic syndromes. Gross examination of the mass in this case was also atypical given the appearance that the mass was rooted in the omentum and invading the small bowel which would suggest the primary tumor site was extragastrointestinal. This case demonstrates the need to build a differential diagnosis that includes GIST and the ability to successfully treat this disease if it is identified early in the clinical course.

Development and validation of a preoperative risk nomogram prediction model for gastric gastrointestinal stromal tumors

BACKGROUND AND STUDY AIMS

Gastrointestinal stromal tumors (GIST) carry a potential risk of malignancy, and the treatment of GIST varies for different risk levels. However, there is no systematic preoperative assessment protocol to predict the malignant potential of GIST. The aim of this study was to develop a reliable and clinically applicable preoperative nomogram prediction model to predict the malignant potential of gastric GIST.

PATIENTS AND METHODS

Patients with a pathological diagnosis of gastric GIST from January 2015 to December 2021 were screened retrospectively. Univariate and multivariate logistic analyses were used to identify independent risk factors for gastric GIST with high malignancy potential. Based on these independent risk factors, a nomogram model predicting the malignant potential of gastric GIST was developed and the model was validated in the validation group.

RESULTS

A total of 494 gastric GIST patients were included in this study and allocated to a development group (n = 345) and a validation group (n = 149). In the development group, multivariate logistic regression analysis revealed that tumor size, tumor ulceration, CT growth pattern and monocyte-to- lymphocyte ratio (MLR) were independent risk factors for gastric GIST with high malignancy potential. The AUC of the model were 0.932 (95% CI 0.890-0.974) and 0.922 (95% CI 0.868-0.977) in the development and validation groups, respectively. The best cutoff value for the development group was 0.184, and the sensitivity and specificity at this value were 0.895 and 0.875, respectively. The calibration curves indicated good agreement between predicted and actual observed outcomes, while the DCA indicated that the nomogram model had clinical application.

CONCLUSIONS

Tumor size, tumor ulceration, CT growth pattern and MLR are independent risk factors for high malignancy potential gastric GIST, and a nomogram model developed based on these factors has a high ability to predict the malignant potential of gastric GIST.

The GIST of it all: management of gastrointestinal stromal tumors (GIST) from the first steps to tailored therapy. A bibliometric analysis

PURPOSE

Improvement of patient care is associated with increasing publication numbers in biomedical research. However, such increasing numbers of publications make it challenging for physicians and scientists to screen and process the literature of their respective fields. In this study, we present a comprehensive bibliometric analysis of the evolution of gastrointestinal stromal tumor (GIST) research, analyzing the current state of the field and identifying key open questions going beyond the recent advantages for future studies to assess.

METHODS

Using the Web of Science Core Collection, 5040 GIST-associated publications in the years 1984-2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and VOSviewer software.

RESULTS

GIST-associated publication numbers substantially increased over time, accentuated from year 2000 onwards, and being characterized by multinational collaborations. The main topic clusters comprise surgical management, tyrosine kinase inhibitor (TKI) development/treatment, diagnostic workup, and molecular pathophysiology. Within all main topic clusters, a significant progress is reflected by the literature over the years. This progress ranges from conventional open surgical techniques over minimally invasive, including robotic and endoscopic, resection techniques to increasing identification of specific functional genetic aberrations sensitizing for newly developed TKIs being extensively investigated in clinical studies and implemented in GIST treatment guidelines. However, especially in locally advanced, recurrent, and metastatic disease stages, surgery-related questions and certain specific questions concerning (further-line) TKI treatment resistance were infrequently addressed.

CONCLUSION

Increasing GIST-related publication numbers reflect a continuous progress in the major topic clusters of the GIST research field. Especially in advanced disease stages, questions related to the interplay between surgical approaches and TKI treatment sensitivity should be addressed in future studies.

Proteomic Characterization Identifies Clinically Relevant Subgroups of Gastrointestinal Stromal Tumors

BACKGROUND & AIMS

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract, and it has high metastatic and recurrence rates. We aimed to characterize the proteomic features of GIST to understand biological processes and treatment vulnerabilities.

METHODS

Quantitative proteomics and phosphoproteomics analyses were performed on 193 patients with GIST to reveal the biological characteristics of GIST. Data-driven hypotheses were tested by performing functional experiments using both GIST cell lines and xenograft mouse models.

RESULTS

Proteomic analysis revealed differences in the molecular features of GISTs from different locations or with different histological grades. MAPK7 was identified and functionally proved to be associated with tumor cell proliferation in GIST. Integrative analysis revealed that increased SQSTM1 expression inhibited the patient response to imatinib mesylate. Proteomics subtyping identified 4 clusters of tumors with different clinical and molecular attributes. Functional experiments confirmed the role of SRSF3 in promoting tumor cell proliferation and leading to poor prognosis.

CONCLUSIONS

Our study provides a valuable data resource and highlights potential therapeutic approaches for GIST.

Acute Pyelonephritis and an Incidental Diagnosis

Gastrointestinal stromal tumors (GISTs) arise from the gastrointestinal tract. In rare cases, extra-gastrointestinal stromal tumors (EGISTs) occur in the omentum, mesentery, et cetera. They are mostly asymptomatic or have unspecific symptoms. Risk stratification classification systems are based on tumor size, mitotic rate, location, and perforation. The gold standard for diagnosis is a computed tomography (CT) scan. Ultrasound/CT-guided percutaneous biopsy allows histopathology and immunochemistry results (most stain positive for CD117 (c-KIT), CD34, and/or DOG1). Mutational analysis (most are in proto-oncogene c-KIT and platelet-derived growth factor receptor A (PDGFRA)) determines appropriate therapy. Surgical resection is the gold standard of treatment, with adjuvant and neoadjuvant molecular-targeted therapies depending on recurrence risk and mutations. This report describes a rare case of GIST (omentum EGIST) with a rare presentation (acute pyelonephritis) in a 67-year-old woman. Abdominal examination showed tenderness and a positive Murphy sign on the left side. Blood analysis presented microcytic hypochromic anemia, aggravated renal function, leukocytosis, and increased C-reactive protein. Abdominal CT revealed a heterogeneous abdominal mass, and a CT-guided biopsy showed epithelioid cells positive for CD117 and DOG1, which is compatible with a GIST. The patient underwent surgery that determined the GIST's origin from the greater omentum. Histology revealed an epithelioid GIST with large dimensions and a high histologic grade. Genetic testing detected a variant in the PDGFRA gene. With a high risk of progression, the patient received a three-year course of imatinib.

Exploring Perforated Jejunal GIST: A Rare Case Report and Review of Molecular and Clinical Literature

This case report details a rare instance of a perforated jejunal gastrointestinal stromal tumor (GIST) in a 76-year-old female patient. The patient presented with acute abdominal pain and distension without any changes in bowel habits or episodes of nausea and vomiting. Initial diagnostics, including abdominal plain radiography and ultrasonography, were inconclusive; however, a computed tomography (CT) scan revealed pneumoperitoneum and an irregular fluid collection suggestive of small intestine perforations. Surgical intervention uncovered a 35 mm jejunal GIST with a 10 mm perforation. Histopathological examination confirmed a mixed cell type GIST with high malignancy potential, further substantiated by immunohistochemistry markers CD117, DOG1, and vimentin. Molecular analysis illuminated the role of key oncogenes, primarily KIT and PDGFRA mutations, emphasizing the importance of molecular diagnostics in GIST management. Despite the severity of the presentation, the patient's postoperative recovery was favorable, highlighting the effectiveness of prompt surgical and multidisciplinary approaches in managing complex GIST cases.

Advances in Drug Therapy for Gastrointestinal Stromal Tumour

INTRODUCTION

Gastrointestinal stromal tumour (GIST) is a common gastrointestinal sarcoma located in the stromal cells of the digestive tract, and molecular studies have revealed the pathogenesis of mutations in KIT and PDGFRA genes. Since imatinib opened the era of targeted therapy for GIST, tyrosine kinase inhibitors (TKIs) that can treat GIST have been developed successively. However, the lack of new drugs with satisfactory therapeutic standards has made addressing resistance a significant challenge for TKIs in the face of the resistance to first-line and second-line drugs. Therefore, we need to find as many drugs and new treatments that block mutated genes as possible.

METHODS

We conducted a comprehensive collection of literature using databases, integrated and analysed the selected literature based on keywords and the comprehensive nature of the articles, and finally wrote articles based on the content of the studies.

RESULTS

In this article, we first briefly explained the relationship between GIST and KIT/ PDGFRα and then introduced the related drug treatment. The research progress of TKIs was analyzed according to the resistance of the drugs.

CONCLUSION

This article describes the research progress of some TKIs and briefly introduces the currently approved TKIs and some drugs under investigation that may have better therapeutic effects, hoping to provide clues to the research of new drugs.

Diagnosis, Treatment, and Prognosis of Patients with Primary Familial Gastrointestinal Stromal Tumor: A Case Report and Literature Review

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the digestive tract, most of which are sporadic, and familial GISTs with germline mutations are rarely seen. Here, we report a 26-year-old female with a germline p. W557R mutation in exon 11 of the KIT gene. The proband and her father and sister presented with multifocal GIST and pigmented nevi. All 3 patients underwent surgery and imatinib therapy. To date, only 49 kindreds with germline KIT mutations and 6 kindreds with germline PDGFRA mutations have been reported. Summarizing the reported kindreds, the majority of familial GISTs manifest as multiple primary GISTs complicated with special clinical manifestations, including cutaneous hyperpigmentation, dysphagia, mastocytosis, inflammatory fibrous polyps, and large hands. Familial GISTs are generally thought to exhibit TKI sensitivity similar to that of sporadic GISTs with the same mutation.

Gastrointestinal Stromal Tumor Complicated by Fistula Formation

Gastrointestinal (GI) stromal tumors are mesenchymal tumors that may arise in any portion of the GI tract. Their clinical presentation and complications may vary but do not often present with fistulization. This case is of clinical interest because of the rarity of GI stromal tumor intestinal fistulas.

The prognostic role of gastrointestinal bleeding in patients with a primary gastrointestinal stromal tumor: a long-term follow-up study

Background

Gastrointestinal (GI) bleeding is one of the common symptoms of GI stromal tumor (GIST). Although several studies have highlighted its prognostic role, conclusions have been inconsistent. This study aimed to investigate the prognosis of GIST patients with GI bleeding.

Methods

Primary GIST patients who underwent complete resection and did not receive adjuvant imatinib therapy from January 2003 to December 2008 were reviewed. The Kaplan-Meier method was used to estimate recurrence-free survival (RFS), and multivariate analysis was performed using the Cox proportional hazard model. Propensity score matching (PSM) was conducted to reduce confounders. A systematic review of the published articles in the PubMed, Embase, Cochrane Collaboration, and Medline databases was also conducted, and the inclusion criteria were determined using PICOS (patients, intervention, comparison, outcomes, and study design) principles.

Results

In total, 84 patients presenting with GI bleeding and 90 patients without GI bleeding were enrolled in this study. The median time of follow-up was 140 months (range, 10-196 months), and 38 patients developed tumor recurrence/metastasis. For all patients, the multivariate analysis indicated that tumor location [hazard ratio (HR) =3.48, 95% confidence interval (CI): 1.78-6.82, P<0.001], tumor size (HR =1.91, 95% CI: 1.05-3.47, P=0.035), mitotic index (MI; HR =5.69, 95% CI: 2.77-11.67, P<0.001), and age (HR =2.68, 95% CI: 1.49-4.82, P=0.001) were the independent prognostic factors for poor RFS. However, GI bleeding was not associated with RFS (HR =1.21, 95% CI: 0.68-2.14, P=0.518). After PSM, 45 patients from each group were included, and it was found that GI bleeding was still not the independent prognostic factor (HR =1.23, 95% CI: 0.51-2.97, P=0.642). Moreover, the pooled results of our study and six previously reported studies showed that GI bleeding was not the independent prognostic factor (HR =1.45, 95% CI: 0.73-2.86, P=0.287).

Conclusions

In this study, tumor location, tumor size, MI, and age were independent prognostic factors in primary GIST patients who underwent radical resection. However, GI bleeding was not associated with worse RFS.

Molecular landscape and clinical significance of exon 11 mutations in KIT gene among patients with gastrointestinal stromal tumor: a retrospective exploratory study

Objective

This aim of this study was to investigate the prognostic significance of KIT exon 11 mutation subtypes in patients with GISTs.

Methods

A total of 233 consecutive patients diagnosed with GISTs at the First Affiliated Hospital of Zhengzhou University from January 2013 to August 2018 were included in this study. The prevalence and mutation landscape of exon 11 in KIT was presented. The clinicopathological characteristics and prognosis among the different mutation subtypes were analyzed. All the statistical analyses were performed by SPSS22.0.

Results

Somatic mutational analysis indicated that point mutations were the most frequently detected mutations followed by deletions & compound mutations and insertion and tandem duplication mutations in the stomach. Point mutations showed a low mitotic count and a high risk of recurrence, and deletions and compound mutations have a high mitotic count while insertions and tandem duplication mutations showed a low mitotic count with an intermediate recurrence risk. Point mutations and deletions frequently occurred in sequence region codons 550-560 of exon 11, while compound mutations, insertion, and tandem duplication were mainly detected in codons 557-559, 572-580, and 577-581, respectively. The multi-variation analysis demonstrated that tumor diameter and high recurrence risk groups had worse prognostic values. However, mutation types were not significant predictors of relapse-free survival (RFS) in GISTs. Survival analysis suggested no significant difference in RFS between the 557/558 deletion and the other deletions.

Conclusion

This study suggested that mutations in exon 11 of the KIT gene were common with intermediate/high recurrence risk in GISTs patients. Tumor diameter ≥5 cm, and deletions mutations might predict a worse prognosis.

Imatinib plasma levels in patients with gastrointestinal stromal tumour under routine clinical practice conditions

OBJECTIVES

Imatinib is the first therapeutic option for the treatment of unresectable or metastatic gastrointestinal stromal tumours. Previous studies have shown an improvement in patient survival rates following the use of imatinib. Nevertheless, adequate plasma concentrations of imatinib are necessary to achieve such improvement in survival and limit the toxicity of the drug. This study aims to analyse the influence of imatinib plasma concentrations on efficacy and safety in the treatment of gastrointestinal stromal tumour.

MATERIALS AND METHODS

This descriptive, multicentre study analysed plasma levels of imatinib in patients diagnosed with gastrointestinal stromal tumour in the period 2019-2020. An optimal therapeutic range of 750-1500 ng/mL was established for the patient stratification based on their minimum plasma concentrations measured at the steady state.

RESULTS

This study included 11 patients with metastatic disease in total, among whom only 54.5% (n  =  6) had a minimum plasma concentrations measured at the steady state value within the therapeutic range. A median progression-free survival of 7.0 months was recorded for those patients with minimum plasma concentrations measured at the steady state < 750 ng/mL, while that median progression-free survival value remained unachieved for the group with minimum plasma concentrations measured at the steady state > 750 ng/mL (p  =  0.005). The toxicity rate was 25% and 14.3% for patients with minimum plasma concentrations measured at the steady state > 1500 ng/mL and minimum plasma concentrations measured at the steady state ≤1500 ng/mL, respectively (p  =  0.66).

CONCLUSIONS

The present study aims to describe the correlation between the toxicity and effectiveness of imatinib as a function of minimum plasma concentrations measured at the steady state under routine clinical practice conditions. The results described here show the usefulness of imatinib plasma concentrations monitoring as part of the standard daily routine in our hospitals.

c-Kit Receptors as a Therapeutic Target in Cancer: Current Insights

c-Kit is a type III receptor tyrosine kinase (RTK) that has an essential role in various biological functions including gametogenesis, melanogenesis, hematopoiesis, cell survival, and apoptosis. c-KIT aberrations, either overexpression or loss-of-function mutations, have been implicated in the pathogenesis and development of many cancers, including gastrointestinal stromal tumors, mastocytosis, acute myeloid leukemia, breast, thyroid, and colorectal cancer, making c-KIT an attractive molecular target for the treatment of cancers. Therefore, a lot of effort has been put into investigating the utility of tyrosine kinase inhibitors for the management of c-KIT mutated tumors. This review of the literature illustrates the role of c-KIT mutations in many cancers, aiming to provide insights into the role of TKIs as a therapeutic option for cancer patients with c-KIT aberrations. In conclusion, c-KIT is implicated in different types of cancer, and it could be a successful molecular target; however, proper detection of the underlying mutation type is required before starting the appropriate personalized therapy.

Liver resection for metastatic GIST tumor improves survival in the era of tyrosine kinase inhibitors: a systematic review and meta-analysis

INTRODUCTION

Survival for gastrointestinal stromal tumor (GIST) has been increasing over the years after the introduction of tyrosine kinase inhibitors. However, the role of metastasectomy for GIST is still controversial. Patients are currently treated with imatinib or sunitinib in case of imatinib failures as optimal medical therapy for metastatic GIST.

METHODS

The Pubmed, EMBASE, and Cochrane Library were systematically searched. Overall survival following liver resection ± tyrosine kinase inhibitor treatment for metastatic GIST was compared to treatment with tyrosine kinase inhibitors alone.

RESULTS

Eleven studies including both randomized control trials and retrospective cohort studies were included in the final analysis with a total of 988 patients. Seven studies encompassed data on 556 patients with isolated liver metastases (219 surgery ± drug groups and 337 drug-only groups) were included. Overall survival was significantly improved in patients undergoing liver resection ± drug therapy in comparison to drug therapy alone. [HR (95%CI) = 2.10 (1.58, 2.79); p<0.00001]. Subgroup analysis showed that patients also had improved progression free survival based on 4 studies. [HR (95%CI) = 1.92 (1.43, 2.56); p<0.00001]. In case of concurrent liver and peritoneal metastases, patients showed improved overall survival with aggressive surgical approaches based on 10 studies. [HR (95%CI) = 1.90 (1.56, 2.31); p<0.00001].

CONCLUSION

This meta-analysis found that liver resection for patients with metastatic GIST regardless of peritoneal metastases improved progression free and overall survival in conjunction with tyrosine kinase inhibitors as compared with medical therapy alone. Furthermore, liver resections did not have any immediate detrimental impact on survival in the group of patients selected.

Ripretinib for the treatment of advanced, imatinib-resistant gastrointestinal stromal tumors

Discovery of constitutive activation of KIT/PDGFRA tyrosine kinases in gastrointestinal stromal tumors (GISTs) leads to the development of the targeted drug imatinib. However, the inevitable development of imatinib resistance remains a major issue. Ripretinib is a novel targeted drug that inhibits the activities of a broad spectrum of drug-resistant KIT/PDGFRA mutants. It was approved in 2020 and is currently recommended by major international guidelines as the fourth-line and beyond therapy for advanced GISTs. Emerging evidence shows that ripretinib is superior to sunitinib as a second-line treatment for KIT exon 11-mutated GISTs due to its activity against highly heterogeneous frequently occurring secondary mutations. This review summarizes current data on the use of ripretinib to treat advanced imatinib-resistant GISTs. We also propose future research directions to improve the targeted GIST treatment.

KIT and PDGFRA Mutations and Survival of Gastrointestinal Stromal Tumor Patients Treated with Adjuvant Imatinib in a Randomized Trial

PURPOSE

Limited data are available about the influence of KIT and PDGFRA mutations on overall survival (OS) of patients with gastrointestinal stromal tumor (GIST) treated with adjuvant imatinib.

PATIENTS AND METHODS

The Scandinavian Sarcoma Group XVIII/AIO multicenter trial accrued 400 patients with a high risk for GIST recurrence after macroscopically complete surgery between February 4, 2004, and September 29, 2008. The patients received adjuvant imatinib 400 mg/day for either 1 year or 3 years based on random allocation. We analyzed using conventional sequencing KIT and PDGFRA mutations centrally from 341 (85%) patients who had localized, centrally confirmed GIST, and correlated the results with recurrence-free survival (RFS) and OS in exploratory analyses.

RESULTS

During a median follow-up time of 10 years, 164 RFS events and 76 deaths occurred. Most patients were re-treated with imatinib when GIST recurred. Patients with KIT exon 11 deletion or indel mutation treated with 3 years of adjuvant imatinib survived longer than patients treated for 1 year [10-year OS 86% versus 64%, respectively; HR, 0.34; 95% confidence interval (CI), 0.15-0.72; P = 0.007], and also had longer RFS (10-year RFS 47% versus 29%; HR, 0.48; 95% CI, 0.31-0.74; P < 0.001). Patients with KIT exon 9 mutation had unfavorable OS regardless of the duration of adjuvant imatinib.

CONCLUSIONS

Compared with 1 year of imatinib, 3 years of adjuvant imatinib led to 66% reduction in the estimated risk of death and a high 10-year OS rate in the subset of patients with a KIT exon 11 deletion/indel mutation.

Prognostic Role of Preoperative Onodera's Prognostic Nutritional Index (OPNI) in Gastrointestinal Stromal Tumors: a Systematic Review and Meta-analysis

PURPOSE

The inflammatory parameters of peripheral blood are related to the prognosis of various cancers. The aim of this meta-analysis is to explore the prognostic value of preoperative OPNI in gastrointestinal stromal tumors (GIST).

METHODS

The following search strategies were used to locate all literature published up to May 1, 2022: PubMed, Web of Science, CBM, EMBASE, and Cochrane, using the keywords "Prognosis," "survival," "Nutritional Assessment," "Nutrition Index," and "PNI," "OPNI," "Gastrointestinal stromal tumor," and "GIST." Studies that did not report an associated cumulative hazard ratio (HR) of recurrence-free survival (RFS) were excluded. The pooled hazard ratio (HR) and corresponding 95% confidence intervals (CI) were calculated by a fixed-effects model. Subgroups were analyzed for heterogeneity of studies, and Egger's test was applied to assess the risk of publication bias.

RESULTS

Through the inclusion and exclusion criteria, 8 articles with a total of 2462 patients with gastrointestinal stromal tumors were selected for analysis. The HR summary of univariate analysis of RFS was 2.73 (95% CI: 2.17-3.43, P < 0.0001), and there was no heterogeneity, which indicated that the prognosis of gastrointestinal stromal tumors with low OPNI before operation was poor. Except for one article that did not give the HR of RFS under the condition of multi-factor analysis, the other 7 articles gave the HR of RFS and summarized it to 1.81 (95% CI: 1.40-3.83, P < 0.0001). Although there was slight heterogeneity in the multifactorial analysis, the publication bias risk and sensitivity assessment showed that the results were still reliable (p > 0.05).

CONCLUSION

The results of this systematic review and meta-analysis show that decreased preoperative OPNI is closely associated with poor long-term survival (RFS) in GIST patients. Monitoring OPNI in GIST patients may help with risk stratification and individualized treatment.

Surgical Management of Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors (GISTs) are considered rare, but they are one of the most common malignant mesenchymal tumors within the gastrointestinal tract, affecting 4,000 to 6,000 adults in the United States each year. Because gastrointestinal bleeding is often the initial symptom, a thorough and timely diagnostic workup is imperative to accurately diagnose a potentially deadly tumor. Endoscopic ultrasound is helpful when working through a differential diagnosis of subepithelial lesions and can help identify which mucosal layer the lesion originates from, as well as the density of the lesion; however, surgical resection is the standard of care for the treatment of a resectable nonmetastatic GIST. For recurrent GISTs, metastatic disease, or GISTs not amendable to resection, tyrosine kinase inhibitors are frequently used, with imatinib being used in the first-line setting. A multimodal treatment approach is often necessary to increase the chances of a permanent cure.

Gastrointestinal Stromal Tumours (GISTs) with KRAS Mutation: A Rare but Important Subset of GISTs

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the GI tract, usually found in the stomach, jejunum, and ileum. Typically, they are KIT or PDGFR-mutated, allowing for targetable treatments with tyrosine kinase inhibitors such as imatinib. Here, we present two KRAS-mutated wild-type gastrointestinal tumours (GISTs). Both cases occurred in the small bowel of females. Immunohistochemical studies on both tumours showed KIT and DOG-1 positivity, with SDHB retained. Molecular analysis revealed a KRAS G12D mutation and a KRAS G13D mutation, respectively. Wild-type GISTs are extremely uncommon. They typically occur in the stomach or the small bowel. KRAS is one of the genes implicated in this subset of GIST, with KRAS G12D being the most frequently encountered mutation. GIST KRAS mutations can arise alone or in conjunction with KIT, PDFRA, or BRAF mutations. Identification of these rare molecular subtypes is clinically important due to their resistance to imatinib therapy.

KIT and PDGFRA Variants and the Survival of Patients with Gastrointestinal Stromal Tumor Treated with Adjuvant Imatinib

Adjuvant imatinib improves the recurrence-free survival and overall survival (OS) of patients with gastrointestinal stromal tumors (GISTs) who have a high risk of recurrence after surgery and is now considered standard treatment. Yet, OS benefit has been demonstrated in only one randomized study, the Scandinavian Sarcoma Group XVIII/AIO trial, where patients with high-risk GISTs were allocated to either 1 year or 3 years of adjuvant imatinib. SSGXVIII/AIO is also the only randomized trial in which adjuvant imatinib duration exceeding 2 years was evaluated. In this trial, the 3-year treatment led to a 45% reduction in the risk of death during the first 10 years that followed random allocation even though some of the patients did not have GISTs at tumor histology review, had mutations now known to be imatinib-resistant or had non-localized disease at study entry. In the subgroup of patients who had KIT exon 11 deletion/indel mutation, the reduction in the risk of death was 66% in favor of the longer treatment. Proper patient selection is of crucial importance since many patients are cured with surgery. Little evidence for OS benefit is available from randomized trials for patients whose GIST harbors KIT exon 9 mutation, KIT insertion mutation, PDGFRA D842V mutation, or lacks KIT and PDGFRA mutations. Adjuvant imatinib improves OS substantially if high-risk GISTs can be identified, treatment duration is long enough, and GISTs harbor an imatinib-sensitive mutation.

Tumor Microenvironment Remodeling in Gastrointestinal Cancer: Role of miRNAs as Biomarkers of Tumor Invasion

Gastrointestinal (GI) cancers are the most frequent neoplasm, responsible for half of all cancer-related deaths. Metastasis is the leading cause of death from GI cancer; thus, studying the processes that regulate cancer cell migration is of paramount importance for the development of new therapeutic strategies. In this review, we summarize the mechanisms adopted by cancer cells to promote cell migration and the subsequent metastasis formation by highlighting the key role that tumor microenvironment components play in deregulating cellular pathways involved in these processes. We, therefore, provide an overview of the role of different microRNAs in promoting tumor metastasis and their role as potential biomarkers for the prognosis, monitoring, and diagnosis of GI cancer patients. Finally, we relate the possible use of nutraceuticals as a new strategy for targeting numerous microRNAs and different pathways involved in GI tumor invasiveness.

Relationship between multi-slice computed tomography features and pathological risk stratification assessment in gastric gastrointestinal stromal tumors

BACKGROUND

Computed tomography (CT) imaging features are associated with risk stratification of gastric gastrointestinal stromal tumors (GISTs).

AIM

To determine the multi-slice CT imaging features for predicting risk stratification in patients with primary gastric GISTs.

METHODS

The clinicopathological and CT imaging data for 147 patients with histologically confirmed primary gastric GISTs were retrospectively analyzed. All patients had received dynamic contrast-enhanced CT (CECT) followed by surgical resection. According to the modified National Institutes of Health criteria, 147 lesions were classified into the low malignant potential group (very low and low risk; 101 lesions) and high malignant potential group (medium and high-risk; 46 lesions). The association between malignant potential and CT characteristic features (including tumor location, size, growth pattern, contour, ulceration, cystic degeneration or necrosis, calcification within the tumor, lymphadenopathy, enhancement patterns, unenhanced CT and CECT attenuation value, and enhancement degree) was analyzed using univariate analysis. Multivariate logistic regression analysis was performed to identify significant predictors of high malignant potential. The receiver operating curve (ROC) was used to evaluate the predictive value of tumor size and the multinomial logistic regression model for risk classification.

RESULTS

There were 46 patients with high malignant potential and 101 with low-malignant potential gastric GISTs. Univariate analysis showed no significant differences in age, gender, tumor location, calcification, unenhanced CT and CECT attenuation values, and enhancement degree between the two groups (P > 0.05). However, a significant difference was observed in tumor size (3.14 ± 0.94 vs 6.63 ± 3.26 cm, P < 0.001) between the low-grade and high-grade groups. The univariate analysis further revealed that CT imaging features, including tumor contours, lesion growth patterns, ulceration, cystic degeneration or necrosis, lymphadenopathy, and contrast enhancement patterns, were associated with risk stratification (P < 0.05). According to binary logistic regression analysis, tumor size [P < 0.001; odds ratio (OR) = 26.448; 95% confidence interval (CI): 4.854-144.099)], contours (P = 0.028; OR = 7.750; 95%CI: 1.253-47.955), and mixed growth pattern (P = 0.046; OR = 4.740; 95%CI: 1.029-21.828) were independent predictors for risk stratification of gastric GISTs. ROC curve analysis for the multinomial logistic regression model and tumor size to differentiate high-malignant potential from low-malignant potential GISTs achieved a maximum area under the curve of 0.919 (95%CI: 0.863-0.975) and 0.940 (95%CI: 0.893-0.986), respectively. The tumor size cutoff value between the low and high malignant potential groups was 4.05 cm, and the sensitivity and specificity were 93.5% and 84.2%, respectively.

CONCLUSION

CT features, including tumor size, growth patterns, and lesion contours, were predictors of malignant potential for primary gastric GISTs.

Correlation Between Tumor Volume and Hemoglobin Level in Gastrointestinal Stromal Tumor

INTRODUCTION

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors. Anemia is a common finding in GIST, but the relationship between tumor volume and anemia severity is not well established.

METHODS

This study aimed to investigate the correlation between the severity of anemia and various factors, mainly tumor volume, in GIST patients who underwent surgical resection. The study included 20 patients with GIST who underwent surgical resection at a tertiary care center. Demographic data, clinical presentation, hemoglobin level, radiological findings, surgical procedure, tumor characteristics, pathological findings, and immunohistochemical analysis were recorded. The tumor volume was calculated from the final resected tumor dimensions.

RESULTS

The mean age of the patients was 53.8 ± 12 years. Eleven were males, and nine were females. The most common presentation was upper gastrointestinal bleeding (50%), followed by pain in the abdomen (35%). The most common tumor location was the stomach (75%). The mean hemoglobin level was 10.29 ± 1.9 g/dL. The mean tumor volume was 470.8 ± 1269.07 cc. R0 resection was achieved in 18 (90%) patients. There was no significant correlation between tumor volume and hemoglobin level (r=0.227, p=0.358).

CONCLUSION

This study found no significant correlation between tumor volume and the severity of anemia in patients with GIST. Further studies with larger sample sizes are needed to validate these findings.

Primary vulvar extragastrointestinal stromal tumor in a 77-year-old woman

Extragastrointestinal stromal tumors (EGISTs) carry the same morphological, immunohistochemical and molecular features as gastrointestinal stromal tumors (GISTs) and involve extragastrointestinal tract soft tissue. The majority of reported EGIST cases arise from intraabdominal, retroperitoneal, or pelvic soft tissue. A significant subset of such tumors originates from the gastrointestinal muscle layer, grows in an exophytic manner, then loses attachment to the gastrointestinal tract. Consequently, true EGISTs are exceedingly rare. Herein, we are reporting a case of a vulvar EGIST. A 77-year-old woman presented with a painless subcutaneous nodule on the right perineum. An excisional biopsy showed a fairly circumscribed bland spindle cell lesion in the dermis. The tumor cells were positive for CD117 and ANO1/DOG-1 and negative for smooth muscle myosin, smooth muscle actin, STAT6, low- and high-molecular-weight cytokeratins, SOX10, MART-1, CD10, S-100 protein, and estrogen and progesterone receptors. A diagnosis of EGIST was made and complete excision was recommended. Superficial/subcutaneous EGISTs are extremely rare, and it is important for dermatopathologists to be aware of this entity as it can be misdiagnosed as more common spindle cell neoplasms, both benign and malignant, including but not limited to smooth muscle neoplasms (leiomyoma/leiomyosarcoma), spindle cell melanoma, and sarcomatoid squamous cell carcinoma.

Neurofibromatosis type 1 with multiple gastrointestinal stromal tumors: A case report

BACKGROUND

Neurofibromatosis type 1 (NF1) is characterized by café-au-lait patches on the skin and the presence of neurofibromas. Gastrointestinal stromal tumor (GIST) is the most common non-neurological tumor in NF1 patients. In NF1-associated GIST, KIT and PDGFRA mutations are frequently absent and imatinib is ineffective. Surgical resection is first-line treatment.

CASE SUMMARY

A 56-year-old woman with NF1 was hospitalized because of an incidental pelvic mass. Physical examination was notable for multiple café-au-lait patches and numerous subcutaneous soft nodular masses of the skin of the head, face, trunk, and limbs. Her abdomen was soft and nontender. No masses were palpated. Digital rectal examination was unremarkable. Abdominal computed tomography was suspicious for GIST or solitary fibrous tumor. Laparoscopy was performed, which identified eight well-demarcated masses in the jejunum. All were resected and pathologically diagnosed as GISTs. The patient was discharged on day 7 after surgery without complications. No tumor recurrence was evident at the 6-mo follow-up.

CONCLUSION

Laparoscopy is effective for both diagnosis and treatment of NF1-associated GIST.

Endoscopic full‑thickness resection with clip‑ and snare‑assisted traction for gastric submucosal tumours in the fundus: A single‑centre case series

Exposed endoscopic full-thickness resection (Eo-EFTR) has been recognized as a feasible therapy for gastrointestinal submucosal tumours (SMTs) originating deep in the muscularis propria layer; however, Eo-EFTR is difficult to perform in a retroflexed fashion in the gastric fundus. As a supportive technique, clip- and snare-assisted traction may help expose the surgical field and shorten the operation time in endoscopic resection of difficult regions. However, the application of clip- and snare-assisted traction in Eo-EFTR of SMTs in the gastric fundus is limited. Between April 2018 and December 2021, Eo-EFTR with clip- and snare-assisted traction was performed in 20 patients with SMTs in the gastric fundus at The First Affiliated Hospital of Soochow University. The relevant clinical data were collected retrospectively for all of the patients and analysed. All 20 patients underwent Eo-EFTR successfully without conversion to open surgery or severe adverse events. The en bloc resection rate and R0 resection rate were both 100%. Two patients had abdominal pain and fever after the operation, and five patients had fever, which recovered with medical therapy. No complications, such as delayed bleeding or delayed perforation, were observed. The postoperative pathology indicated that 19 cases were gastrointestinal stromal tumours and one case was leiomyoma. During the follow-up, no residual tumour, local recurrence or distant metastasis was detected by endoscopy or abdominal computed tomography. In conclusion, Eo-EFTR with clip- and snare-assisted traction appears to be a relatively safe and effective treatment for gastric SMTs in the fundus. However, prospective studies on a larger sample size are required to verify the effect of the clip- and snare-assisted traction in Eo-EFTR.

Neoadjuvant versus adjuvant imatinib in primary localized gastrointestinal stromal tumor

Background

The effect of neoadjuvant therapy (NAT) with imatinib versus upfront resection (UR) followed by adjuvant therapy (AT) with imatinib on the outcomes of gastrointestinal stromal tumors (GIST) is unknown.

Methods

This is a retrospective study at a high-volume center. All the patients with primary localized GIST were identified in a hospital database from 2007 to 2021. The endpoints included local recurrence-free survival (LRFS), distance recurrence-free survival (DRFS), and overall survival (OS). Cox regression was used to perform multivariate survival analyses. The sensitivity analysis was conducted with the inverse probability of treatment weighting (IPTW) method.

Results

A total of 211 patients were included (Group A: UR + AT, n=140; Group B: NAT + resection + AT, n=71). In the entire cohort, 5-year DRFS, LRFS, and OS were 85.6%, 90.7%, and 92.5%, respectively. In the multivariate analysis, better DRFS was linked to NAT, tumor size of 5 cm, and AT. Sixteen patients (11.4%) in Group A and 1 (1.4%) in Group B had distant recurrences after AT discontinuation. The sensitivity analysis by IPTW provided approximately similar results. An interaction effect was observed between NAT and tumor location on DRFS. In non-gastric GISTs, NAT was associated with better DRFS [hazard ratio =0.131, 95% confidence interval (CI): 0.017-0.989, P=0.049], which was not the case in gastric GIST (P=0.08). NAT was not independently associated with LRFS or OS.

Conclusions

When compared to UR + AT, NAT + resection + AT may reduce the risk of distant recurrence in localized GIST and may be especially beneficial for patients with non-gastric GISTs.

CT-based assessment of sarcopenia for differentiating wild-type from mutant-type gastrointestinal stromal tumor

Non-invasive prediction for KIT/PDGFRA status in GIST is a challenging problem. This study aims to evaluate whether CT based sarcopenia could differentiate KIT/PDGFRA wild-type gastrointestinal stromal tumor (wt-GIST) from the mutant-type GIST (mu-GIST), and to evaluate genetic features of GIST. A total of 174 patients with GIST (wt-GIST = 52) were retrospectively identified between January 2011 to October 2019. A sarcopenia nomogram was constructed by multivariate logistic regression. The performance of the nomogram was evaluated by discrimination, calibration curve, and decision curve. Genomic data was obtained from our own specimens and also from the open databases cBioPortal. Data was analyzed by R version 3.6.1 and clusterProfiler ( http://cbioportal.org/msk-impact ). There were significantly higher incidence (75.0% vs. 48.4%) and more severe sarcopenia in patients with wt-GIST than in patients with mu-GIST. Multivariate logistic regression analysis showed that sarcopenia score (fitted based on age, gender and skeletal muscle index), and muscle fat index were independent predictors for higher risk of wt-GIST (P < 0.05 for both the training and validation cohorts). Our sarcopenia nomogram achieved a promising efficiency with an AUC of 0.879 for the training cohort, and 0.9099 for the validation cohort with a satisfying consistency in the calibration curve. Favorable clinical usefulness was observed using decision curve analysis. The additional gene sequencing analysis based on both our data and the external data demonstrated aberrant signal pathways being closely associated with sarcopenia in the wt-GIST. Our study supported the use of CT-based assessment of sarcopenia in differentiating the wt-GIST from the mu-GIST preoperatively.

Gestational trophoblastic neoplasia with primary lung cancer and mesenchymal tumor of sigmoid colon: a case report and literature review

BACKGROUND

Gestational trophoblastic neoplasia (GTN) is rare, and it is even rarer for GTN to merge with primary malignant tumors in other organs. Herein is described a rare clinical case of GTN combined with primary lung cancer and mesenchymal tumor of the sigmoid colon, followed with literature review.

CASE PRESENTATION

The patient was hospitalized due to diagnosis of GTN with primary lung cancer. Firstly, two cycles of chemotherapy including 5-fluorouracil (5-FU) and actinomycin-D(Act-D) was given. Laparoscopic total hysterectomy and right salpingo-oophorectomy was performed during the third chemotherapy. During the operation, a 3*2 cm nodule was removed which was protruded from the serous surface of the sigmoid colon, and the nodule was confirmed mesenchymal tumor pathologically, in accord with gastrointestinal stromal tumor. During the treatment of GTN, Icotinib tablets were taken orally to control the progression of lung cancer. After 2 cycles of consolidation chemotherapy of GTN, she received thoracoscopic lower lobe of right lung lobectomy and the mediastinum lymph nodes removal. She undertook gastroscopy and colonoscopy and the tubular adenoma of the descending colon was removed. At present, the regular follow-up is taken and she remains free of tumors.

CONCLUSIONS

GTN combined with primary malignant tumors in other organs are extremely rare in clinical practice. When imaging examination reveals a mass in other organs, clinicians should be aware of the possibility of a second primary tumor. It will increase the difficulty of GTN staging and treatment. We emphasis the importance of the collaboration of multidisciplinary teams. Clinicians should choose a reasonable treatment plan according to the priorities of different tumors.

Endoscopic Ultrasound Advanced Techniques for Diagnosis of Gastrointestinal Stromal Tumours

Gastrointestinal Stromal Tumors (GISTs) are subepithelial lesions (SELs) that commonly develop in the gastrointestinal tract. GISTs, unlike other SELs, can exhibit malignant behavior, so differential diagnosis is critical to the decision-making process. Endoscopic ultrasound (EUS) is considered the most accurate imaging method for diagnosing and differentiating SELs in the gastrointestinal tract by assessing the lesions precisely and evaluating their malignant risk. Due to their overlapping imaging characteristics, endosonographers may have difficulty distinguishing GISTs from other SELs using conventional EUS alone, and the collection of tissue samples from these lesions may be technically challenging. Even though it appears to be less effective in the case of smaller lesions, histology is now the gold standard for achieving a final diagnosis and avoiding unnecessary and invasive treatment for benign SELs. The use of enhanced EUS modalities and elastography has improved the diagnostic ability of EUS. Furthermore, recent advancements in artificial intelligence systems that use EUS images have allowed them to distinguish GISTs from other SELs, thereby improving their diagnostic accuracy.

Sunitinib versus imatinib dose escalation after failure of imatinib standard dose in patients with advanced Gastrointestinal stromal tumors - a real-world multi-center study

BACKGROUND

Whether to escalate imatinib dosage or directly switch to sunitinib in gastrointestinal stromal tumors (GISTs) failing on standard dose 400 mg/d of imatinib is still controversial.

METHODS

We evaluated progression-free survival (PFS), overall survival (OS), and time to sunitinib failure (TTSF) of patients selecting imatinib dose escalation or directly switching to sunitinib after the failure of imatinib 400 mg/d therapy from 3 tertery referring centers between January 2008 to December 2016.

RESULTS

A total of 240 patients receiving sunitinib (37.5 mg continuous daily dose or 50 mg 4 weeks on with 2 weeks off) for at least 8 weeks were examined. After failure on imatinib 400 mg/d, 100 (49.3%) patients had dose escalation to 600 mg or 800 mg per day (IM group, imatinib group), and 103 (50.7%) directly switched to sunitinib (SU group, sunitinib group). The PFS in the SU and IM groups was 12 months and 5.0 months (P < 0.001), respectively. TTSF or OS in both groups was not statistically significantly different.

CONCLUSIONS

After the progression of imatinib standard-dose treatment in recurrent/metastatic GISTs, the PFS of patients directly switching to sunitinib was significantly longer compared with the PFS of patients with imatinib dose escalation. However, when the patients continued with sunitinib therapy after the failure of IM dose escalation, TTSF and OS in the IM group were similar to those in the SU group. Further exploration of the characteristics of the population benefiting from imatinib dose escalation are warranted.

Is CT or FDG-PET more useful for evaluation of the treatment response in metastatic HER2-positive breast cancer? a case report and literature review

Response evaluation criteria in solid tumors version 1.1 (RECIST ver1.1) has been widely adopted to evaluate treatment efficacy in solid tumors, including breast cancer (BC), in clinical trials and clinical practice. RECIST is based mainly on computed tomography (CT) images, and the role of fluorodeoxyglucose-positron emission tomography (FDG-PET) is limited. However, because the rate of tumor shrinkage on CT does not necessarily reflect the potential remaining tumor cells, there may be a discrepancy between the treatment response and prognosis in some cases. Here we report a case of metastatic human epidermal growth factor receptor 2 (HER2)-positive BC where FDG-PET was preferable to CT for evaluation of the treatment response. A 40-year-old woman became aware of a lump in her right breast in September 201X. She was pregnant and underwent further examinations, including a biopsy, in November. The diagnosis was HER2-positive BC (cT2N2bM1, stage IV). Trastuzumab plus pertuzumab plus docetaxel (TPD) therapy was initiated in December 201X. CT performed in February 201X+1 showed cystic changes in the metastatic lesions in the liver, and the treatment response was stable disease (SD) according to RECIST. However, FDG-PET in March 201X+1 did not detect abnormal uptake of FDG in the hepatic lesions. The disease remained stable thereafter. Thus, tumor shrinkage may not be apparent in situations where the response to treatment results in rapid changes in blood flow within the tumor, which is associated with cystic changes. When patients with hypervascular liver metastases receive treatment with highly effective regimens, the target lesion may show cystic changes rather than shrinkage, as observed in the present case. Therefore, FDG-PET is sometimes superior to CT in judging a tumor response.

An Unusual Case of Suspected Metastatic Gastrointestinal Stromal Tumor Complicated by Streptococcus Intermedius Pyogenic Liver Disease

A gastrointestinal stromal tumor (GIST) is a mesenchymal neoplasm of the gastrointestinal tract often known to express c-KIT or platelet-derived growth factor receptor alpha (PDGFRα). Among all GI tract cancers, they account for less than 1% of cases. Most patients become symptomatic in the later stages of the tumor's course, often presenting with insidious anemia due to gastrointestinal bleeding and metastasis. The recommended management of solitary GIST is surgery, while larger or metastatic tumors that express c-KIT are managed with imatinib as either neoadjuvant or adjuvant therapy. Due to the progression of these tumors, they are at times associated with systemic anaerobic infection, which is an indication of malignancy workup. In this case report, we discuss a 35-year-old woman who was discovered to have GIST with possible hepatic metastasis complicated by pyogenic liver disease due to Streptococcus intermedius and the diagnostic challenge of differentiating between infection and tumor.

Advances of endoscopic and surgical management in gastrointestinal stromal tumors

As one of the most common mesenchymal malignancies in the digestive system, gastrointestinal stromal tumors (GISTs) occur throughout the alimentary tract with diversified oncological characteristics. With the advent of the tyrosine kinase inhibitor era, the treatment regimens of patients with GISTs have been revolutionized and GISTs have become the paradigm of multidisciplinary therapy. However, surgery resection remains recognized as the potentially curative management for the radical resection and provided with favorable oncological outcomes. The existing available surgery algorithms in clinical practice primarily incorporate open procedure, and endoscopic and laparoscopic surgery together with combined operation techniques. The performance of various surgery methods often refers to the consideration of risk evaluation of recurrence and metastases; the degree of disease progression; size, location, and growth pattern of tumor; general conditions of selected patients; and indications and safety profile of various techniques. In the present review, we summarize the fundamental principle of surgery of GISTs based on risk assessment as well as tumor size, location, and degree of progress with an emphasis on the indications, strengths, and limitations of current surgery techniques.

The prognostic significance of prognostic nutritional index in gastrointestinal stromal tumors: A systematic review and meta-analysis

BACKGROUND

Risk assessment before treatment is important for gastrointestinal stromal tumors (GISTs), which will determine the priority of surgery or preoperative treatment. The prognostic nutritional index (PNI) is an integrated parameter consisting of serum albumin and lymphocyte count. Immunonutritional status defined in this manner is well-known to be closely linked to the prognosis of several other cancers. Nevertheless, the prognostic value of PNI specifically in GISTs has not been well-established. This study aimed to verify the prognostic role of PNI in patients with GISTs.

METHODS

A comprehensive literature search was conducted on medical databases up to June, 2022, and the raw data (hazard ratios and 95% confidence intervals [CIs]) focusing on the prognostic value of PNI in patients with GISTs regarding recurrence-free survival were extracted and synthesized adopting the random-effects model. This review was registered in the PROSPERO database (CRD42022345440).

RESULTS

A total of 8 eligible studies including 2627 patients with GISTs was analyzed and the pooled results confirmed that an elevated PNI was associated with a better recurrence-free survival (hazard ratio: 0.52, 95% CI: 0.40-0.68), with a moderate heterogeneity (I-square, 38%). The findings from subgroup analysis were consistent with the overall pooled results, and a sensitivity analysis, not the subgroup analysis, identified the source of heterogeneity.

CONCLUSION

Elevated pretreatment PNI may be a useful indicator for assessing risk of recurrence in patients from China with GISTs. Studies in other countries and regions are needed to further verify the prognostic value of PNI in GISTs.

Laparoscopic resection is not superior to endoscopic resection for relative small gastric gastrointestinal stromal tumors: A propensity score-matched study

Background and Aim

Endoscopic resection (ER) and laparoscopic resection (LAP) have been recommended for the treatment of gastric gastrointestinal stromal tumors (GISTs) less than 2 cm. However, the therapeutic approach for gastric GISTs between 2 and 5 cm in diameter is still under debate. In this retrospective study, we aimed to evaluate the feasibility, efficacy, and safety of ER for gastric GISTs (2–5 cm) compared with LAP.

Methods

From January, 2011 to January, 2018, 197 patients with GISTs at our institution with tumor diameter between 2 and 5 cm were included in our study. Clinical baseline characteristics, histopathological results, and perioperative outcomes were collected and compared in all the patients. Propensity score matching (PSM) methods were used to balance baseline characteristics.

Results

There was no significant difference in age (p = 0.246), gender (p = 0.572), tumor location (p = 0.333), pathological risk classification (p = 0.543), Ki-67 index (p = 0.212), and follow-up time (p = 0.831) in the ER and LAP groups. However, significance difference was found in times to liquid diet intake (4.45 ± 1.2 vs. 5.40 ± 1.5 days, p = 0.013) and hospital stays (7.72 ± 1.1 vs. 10.01 ± 1.3 days, p &lt; 0.001). During the follow-up period, there was one recurrence in the ER group vs. two recurrences in the LAP group. After PSM, the tumor size was balanced between the two groups with 49 patients in each group. The times to liquid diet intake (4.18 ± 1.3 vs. 5.16 ± 1.6 days, p = 0.042) and hospital stay days (7.12 ± 1.1 vs. 9.94 ± 1.3, p &lt; 0.0001) were still short in the ER group.

Conclusions

ER is more associated with a quick postoperative recovery than LAP. ER could be an alternative approach for gastric GISTs (2–5 cm). However, the long-term follow-up outcomes are still unclear and random control trials are needed.

Small molecule inhibitors targeting the cancers

Compared with traditional therapies, targeted therapy has merits in selectivity, efficacy, and tolerability. Small molecule inhibitors are one of the primary targeted therapies for cancer. Due to their advantages in a wide range of targets, convenient medication, and the ability to penetrate into the central nervous system, many efforts have been devoted to developing more small molecule inhibitors. To date, 88 small molecule inhibitors have been approved by the United States Food and Drug Administration to treat cancers. Despite remarkable progress, small molecule inhibitors in cancer treatment still face many obstacles, such as low response rate, short duration of response, toxicity, biomarkers, and resistance. To better promote the development of small molecule inhibitors targeting cancers, we comprehensively reviewed small molecule inhibitors involved in all the approved agents and pivotal drug candidates in clinical trials arranged by the signaling pathways and the classification of small molecule inhibitors. We discussed lessons learned from the development of these agents, the proper strategies to overcome resistance arising from different mechanisms, and combination therapies concerned with small molecule inhibitors. Through our review, we hoped to provide insights and perspectives for the research and development of small molecule inhibitors in cancer treatment.

[Gastrointestinal stromal tumors (GIST)]

Gastrointestinal stromal tumors (GIST) are rare tumors with a varying malignancy potential, most frequently located in the stomach and the small intestine. The median age at diagnosis is around 65 years. Standard treatment of localized disease is complete surgical resection. A GIST is generally resistant to conventional chemotherapy. Most GISTs harbor tyrosine kinase activating mutations in either the KIT or PDGFRA proto-oncogene. The standard treatment of locally advanced and metastatic GIST with such mutations is the tyrosine kinase inhibitor imatinib. In cases of progressive disease after successive treatment with imatinib, sunitinib, and regorafenib, a fourth-line therapy with ripretinib was recently approved. Approved in 2020, avapritinib is the first effective targeted therapy for advanced stage GIST harboring an imatinib-resistant PDGFRA D842V mutation.

Long-term adjuvant therapy for high-risk gastrointestinal stromal tumors in the real world

PURPOSE

Three years of adjuvant imatinib is the standard therapy for gastrointestinal stromal tumors (GISTs) with high-risk features. The prognostic effects of long-term adjuvant therapy are unknown.

PATIENTS AND METHODS

The prospective registry study recruited 515 patients with high-risk GISTs between Dec. 2012 and Dec. 2015 were analyzed. The primary endpoint was recurrence-free survival (RFS), and secondary endpoints include overall survival (OS) and safety. The study was designed to compare RFS after 3.5 years of 3-year adjuvant therapy (3.0 ± 0.5 years: 3-year group) with that of more than 3.5 years (median 5.2 years: longer group).

RESULTS

Five-year RFS and 5-year OS were 68.2% (95% confidence interval [CI] 63.8-72.1) and 92.3% (95% CI 89.5-94.4), respectively. The recurrence rate during adjuvant was estimated to be 2.9/100 person-years (95% CI 2.0-4.1) and those after the end of adjuvant, which appeared similar irrespective of the adjuvant duration or reason to stop adjuvant, were estimated 12.0/100 person-years (95% CI 10.2-14.0). The 5-year RFS rates of 3-year and longer groups were 78.7% (95% CI 70.8-84.7) and 92.7% (95% CI 85.2-96.4), respectively. RFS after 3.5 years of the longer group was significantly better than that of the 3-year group (adjusted hazard ratio [HR] 0.56; 95% CI 0.39-0.78; P < 0.001).

CONCLUSION

The recurrence risk of high-risk GISTs after adjuvant therapy is similar irrespective of the adjuvant duration and imatinib adjuvant may not cure but may delay recurrence. RFS after long-term adjuvant therapy appeared better than that after 3-year adjuvant.

Complete response of advanced rectal gastrointestinal stromal tumors after imatinib treatment: A case report and literature review

RATIONALE

Patients with rectal gastrointestinal stromal tumors (GISTs) who achieve a complete response (CR) with imatinib therapy have rarely been reported in the literature. Moreover, no treatment guidelines have been established for rectal GIST patients with CR after imatinib treatment, warranting further studies.

PATIENT CONCERNS

A 51-year-old man presented to our outpatient clinic in October 2013 with complaints of difficulty to defecate and a change in stool characteristics. During digital rectal examination, a mass was palpated within 5 cm from the anal verge. Contrast-enhanced computed tomography revealed a 8.1 × 7.2-cm rectal mass with significant enhancement during the arterial phase.

DIAGNOSES

A diagnosis of GIST was established after conducting needle biopsy and immunohistochemistry staining.

INTERVENTIONS

Imatinib therapy (400 mg/d, oral administration) was immediately started. When the patient achieved clinical CR (cCR), the oncologist recommended the patient to continue imatinib treatment.

OUTCOMES

At 7 months after imatinib administration, the patient achieved cCR. As suggested by the oncologist, the patient continued to receive imatinib treatment after cCR. After 13 months, the patient spontaneously stopped imatinib. Finally, tumor recurrence was observed 7 months later.

LESSONS

Surgery remains the mainstay of treatment for advanced rectal GIST patients who achieve cCR after imatinib treatment. Close follow-up and continuous imatinib treatment are indicated in patients who cannot undergo surgery.

Clinical outcomes of endoscopic treatment for gastric gastrointestinal stromal tumors: a single-center study of 240 cases in China

BACKGROUND AND AIMS

Endoscopic resection (ER) gradually becomes an important treatment method for gastrointestinal stromal tumors (GISTs). The aim of this study is to evaluate the efficacy and safety of ER of gastric GISTs.

METHODS

This retrospective study included 240 patients with gastric GISTs who underwent ER at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from January 2010 to December 2019. The clinicopathologic, endoscopic and follow-up data of the patients were collected and analyzed.

RESULTS

The mean maximum tumor diameter was 1.67 ± 1.00 cm (range 0.2-6.5 cm), of which 156 cases (65.00%) were small gastric GISTs (tumor diameter < 2 cm). A total of 43 patients (17.92%) had perioperative bleeding, including 40 cases (16.67%) of minor bleeding and three cases (1.25%) of major bleeding. Perioperative perforation occurred in 101 patients (42.08%), of which 51 patients (21.25%) were active perforation and 50 patients (20.83%) were passive perforation. The en bloc resection rate was 97.08% (233/240), and seven cases (2.92%) had piecemeal resection. There were three cases (1.92%) of small gastric GISTs at intermediate risk and one case (0.64%) at high risk. A total of 193 patients were followed up, and no tumor residual, recurrence or metastasis occurred within a median follow-up time of 30 months (range 1-127 months).

CONCLUSIONS

Endoscopic treatment for gastric GISTs is safe and effective. Piecemeal resection does not seem to be related to the patient's prognosis. Endoscopic resection can be performed if patients are willing to remove small gastric GISTs.

Radiotherapy in the Management of Gastrointestinal Stromal Tumors: A Systematic Review

Simple Summary

Gastrointestinal stromal tumors are considered to be insensitive to radiotherapy. However, with the development of radiation techniques and the accumulation of cases, some studies have indicated that radiotherapy could help achieve objective response in advanced or metastatic gastrointestinal stromal tumors. Therefore, it is necessary to conduct a systematic review to reassess the role of radiotherapy in gastrointestinal stromal tumors. The purpose of this study was to draw the attention of scholars and clinicians to radiotherapy and promote further research on radiotherapy in gastrointestinal stromal tumors.

Abstract

Gastrointestinal stromal tumors (GISTs) are considered insensitive to radiotherapy. However, a growing number of case reports and case series have shown that some lesions treated by radiotherapy achieved an objective response. The aim of the study was to perform a systematic review of all reported cases, case series, and clinical studies of GISTs treated with radiotherapy to reevaluate the role of radiotherapy in GISTs. A systematic search of the English-written literature was conducted using PubMed, Web of Science, and Embase databases. Overall, 41 articles describing 112 patients were retrieved. The included articles were of low to moderate quality. Bone was the most common site treated by radiotherapy, followed by the abdomen. In order to exclude the influence of effective tyrosine kinase inhibitors (TKIs), a subgroup analysis was conducted on whether and which TKIs were concurrently applied with radiotherapy. Results showed that radiotherapy alone or combined with resistant TKIs could help achieve objective response in selected patients with advanced or metastatic GISTs; however, survival benefits were not observed in the included studies. Pain was the most common symptom in symptomatic GISTs, followed by neurological dysfunction and bleeding. The symptom palliation rate was 78.6% after excluding the influence of effective TKIs. The adverse reactions were mainly graded 1–2. Radiotherapy was generally well-tolerated. Overall, radiotherapy may relieve symptoms for GIST patients with advanced or metastatic lesions and even help achieve objective response in selected patients without significantly reducing the quality of life. In addition to bone metastases, fixed abdominal lesions may be treated by radiotherapy. Publication bias and insufficient quality of included studies were the main limitations in this review. Further clinical studies are needed and justified.

Clinicopathological features of Gastrointestinal Stromal Tumors and review of the literature

Objective: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasias of the gastrointestinal system (GIS). The malignancy potential of GISTs may vary ranging from indolent tumors to progressive malignant tumors. This study aims to define clinicopathological and immunohistochemical features of GISTs diagnosed in our institute with a review of the literature. Method: A total of 28 GIST cases were included in the study. The Hematoxylin&Eosin stained slides of surgical resection materials and cell blocks and immunohistochemistry performed slides were reviewed by a pathologist. The immunohistochemical expression with CD117, DOG-1, CD34, SMA, and S100 was scored between 0 and 3 points according to staining intensity. Descriptive statistics were used in the study. The demographic data, prognostic histopathological, and immunohistochemical findings are evaluated with the literature indications. Result: Eleven of the cases were male and seventeen were female. The age range was 18-88. The most common site of GISTs was the stomach, followed by the small intestine, colorectal region, and, esophagus. Twenty of the tumors were resected surgically, four were endoscopic biopsy material and four were fine-needle aspiration biopsies. The tumor size in measurable materials ranged from 0,2 to 22 cm. The mitotic count in 50 HPF ranges from 0 to 10. Seven of the GISTs were high grade and the remaining 21 were low grade. The majority of the cases were composed of spindle cells, 3 were epithelioid and 3 were the mixed type with spindle and epitheloid cells. Conclusion: A variety of criteria has been proposed to estimate the malignancy potential of GISTs and predict prognosis but definite prognostic criteria remain uncertain. Further studies with larger series of GISTs consisting of different types of biopsy materials may help define criteria to predict prognosis precisely.

Clinical sequencing of soft tissue and bone sarcomas delineates diverse genomic landscapes and potential therapeutic targets

The genetic, biologic, and clinical heterogeneity of sarcomas poses a challenge for the identification of therapeutic targets, clinical research, and advancing patient care. Because there are > 100 sarcoma subtypes, in-depth genetic studies have focused on one or a few subtypes. Herein, we report a comparative genetic analysis of 2,138 sarcomas representing 45 pathological entities. This cohort is prospectively analyzed using targeted sequencing to characterize subtype-specific somatic alterations in targetable pathways, rates of whole genome doubling, mutational signatures, and subtype-agnostic genomic clusters. The most common alterations are in cell cycle control and TP53, receptor tyrosine kinases/PI3K/RAS, and epigenetic regulators. Subtype-specific associations include TERT amplification in intimal sarcoma and SWI/SNF alterations in uterine adenosarcoma. Tumor mutational burden, while low compared to other cancers, varies between and within subtypes. This resource will improve sarcoma models, motivate studies of subtype-specific alterations, and inform investigations of genetic factors and their correlations with treatment response.