Metastatic pattern and prognosis of gastrointestinal stromal tumor (GIST): a SEER-based analysis. Clin Transl Oncol. 2019;21:1654-1662. [PMID: 30905025 DOI: 10.1007/s12094-019-02094-y]

Understanding Gastric GIST: From Pathophysiology to Personalized Treatment

Background: Gastric gastrointestinal stromal tumors (GISTs) represent a subset of gastrointestinal tumors predominantly found in the stomach. Despite their rarity, these tumors carry significant implications for patient health and management. GISTs are potentially malignant tumors with unpredictable progression. They originate from the interstitial cells of Cajal, which are positioned between the intramural neurons and the smooth muscle cells of the digestive tract. These tumors are characterized primarily by mutations in the c-Kit gene, as well as other mutations such as those in the platelet-derived growth factor receptor alpha (PDGFRA) gene. Methods: Our comprehensive search across five databases initially yielded 2976 articles. After eliminating 197 duplicates, we screened the titles and abstracts of 2779 articles, excluding 2692 for not meeting the inclusion criteria. During the full-text screening, 16 more articles were excluded. Ultimately, 71 papers met the inclusion criteria and were included in our analysis. Results: Due to differences in study designs, inclusion criteria for patients, and reported outcomes, a meta-analysis was not conducted. The accurate diagnosis of GIST is established through histopathological examination and immunohistochemistry. Histopathologically, GISTs are classified into three main types: spindle cell, epithelioid, and mixed. The therapeutic management of GIST involves surgery, endoscopic treatment, and chemotherapy. Conclusions: The prognosis for GIST patients depends on various factors, including risk category, disease stage, applied treatments, and recurrence post-treatment. A significant recent advancement comes from artificial intelligence, which can be increasingly involved in both the diagnosis and treatment of this tumor.

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.

A nomogram for predicting liver metastasis in patients with gastric gastrointestinal stromal tumor

BACKGROUND

Liver metastasis (LIM) is an important factor in the diagnosis, treatment, follow-up, and prognosis of patients with gastric gastrointestinal stromal tumor (GIST). There is no simple tool to assess the risk of LIM in patients with gastric GIST. Our aim was to develop and validate a nomogram to identify patients with gastric GIST at high risk of LIM.

METHODS

Patient data diagnosed as having gastric GIST between 2010 and 2019 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into training cohort and internal validation cohort in a 7:3 ratio. For external validation, retrospective data collection was performed on patients diagnosed as having gastric GIST at Yunnan Cancer Center (YNCC) between January 2015 and May 2023. Univariate and multivariate logistic regression analyses were used to identify independent risk factors associated with LIM in patients with gastric GIST. An individualized LIM nomogram specific for gastric GIST was formulated based on the multivariate logistic model; its discriminative performance, calibration, and clinical utility were evaluated.

RESULTS

In the SEER database, a cohort of 2341 patients with gastric GIST was analyzed, of which 173 cases (7.39%) were found to have LIM; 239 patients with gastric GIST from the YNCC database were included, of which 25 (10.46%) had LIM. Multivariate analysis showed tumor size, tumor site, and sex were independent risk factors for LIM (P < .05). The nomogram based on the basic clinical characteristics of tumor size, tumor site, sex, and age demonstrated significant discrimination, with an area under the curve of 0.753 (95% CI, 0.692-0.814) and 0.836 (95% CI, 0.743-0.930) in the internal and external validation cohort, respectively. The Hosmer-Lemeshow test showed that the nomogram was well calibrated, whereas the decision curve analysis and the clinical impact plot demonstrated its clinical utility.

CONCLUSION

Tumor size, tumor subsite, and sex were significantly correlated with the risk of LIM in gastric GIST. The nomogram for patients with GIST can effectively predict the individualized risk of LIM and contribute to the planning and decision making related to metastasis management in clinical practice.

Utility of Clinical Next Generation Sequencing Tests in KIT/PDGFRA/SDH Wild-Type Gastrointestinal Stromal Tumors

Objective: The vast majority of gastrointestinal stromal tumors (GISTs) are driven by activating mutations in KIT, PDGFRA, or components of the succinate dehydrogenase (SDH) complex (SDHA, SDHB, SDHC, and SDHD genes). A small fraction of GISTs lack alterations in KIT, PDGFRA, and SDH. We aimed to further characterize the clinical and genomic characteristics of these so-called "triple-negative" GISTs. Methods: We extracted clinical and genomic data from patients seen at MD Anderson Cancer Center with a diagnosis of GIST and available clinical next generation sequencing data to identify "triple-negative" patients. Results: Of the 20 patients identified, 11 (55.0%) had gastric, 8 (40.0%) had small intestinal, and 1 (5.0%) had rectal primary sites. In total, 18 patients (90.0%) eventually developed recurrent or metastatic disease, and 8 of these presented with de novo metastatic disease. For the 13 patients with evaluable response to imatinib (e.g., neoadjuvant treatment or for recurrent/metastatic disease), the median PFS with imatinib was 4.4 months (range 0.5-191.8 months). Outcomes varied widely, as some patients rapidly developed progressive disease while others had more indolent disease. Regarding potential genomic drivers, four patients were found to have alterations in the RAS/RAF/MAPK pathway: two with a BRAF V600E mutation and two with NF1 loss-of-function (LOF) mutations (one deletion and one splice site mutation). In addition, we identified two with TP53 LOF mutations, one with NTRK3 fusion (ETV6-NTRK3), one with PTEN deletion, one with FGFR1 gain-of-function (GOF) mutation (K654E), one with CHEK2 LOF mutation (T367fs*), one with Aurora kinase A fusion (AURKA-CSTF1), and one with FANCA deletion. Patients had better responses with molecularly targeted therapies than with imatinib. Conclusions: Triple-negative GISTs comprise a diverse cohort with different driver mutations. Compared to KIT/PDGFRA-mutant GIST, limited benefit was observed with imatinib in triple-negative GIST. In depth molecular profiling can be helpful in identifying driver mutations and guiding therapy.

Effects of surgical management for gastrointestinal stromal tumor patients with liver metastasis on survival outcomes

Purpose

To investigate the effect of surgical resection on survival in gastrointestinal stromal tumors synchronous liver metastasis (GIST-SLM) and to develop clinically usable predictive models for overall survival (OS) and cancer-specific survival (CSS) in patients.

Methods

We identified patients in the SEER database diagnosed with GISTs from 2010 to 2019. We used propensity score matching (PSM) to balance the bias between the Surgery and No surgery groups. Kaplan-Meier(K-M) analysis was used to detect differences in OS and CSS between the two groups. The nomogram to predict 1, 3, and 5-year OS and CSS were developed and evaluated.

Results

After PSM, 228 patients were included in this study. There were significant differences in 1, 3, and 5-year OS and CSS between the two groups (OS: 93.5% vs. 84.4%, 73.2% vs. 55.3%, 60.9% vs. 36.9%, P=0.014; CSS: 3.5% vs.86.2%,75.3% vs.57.9%, 62.6% vs. 42.9%, P=0.02). We also found that patients who received surgery combined with targeted therapy had better OS and CSS at 1, 3, and 5 years than those who received surgery only (OS: 96.6% vs.90.9%, 74.9% vs. 56.8%, 61.7% vs. 35.5%, P=0.022; CSS: 96.6% vs. 92.1%, 77.4% vs.59.2%,63.8% vs. 42.0%, P=0.023). The area under the curve (AUC) was 0.774, 0.737, and 0.741 for 1, 3, and 5-year OS, respectively, with 0.782 and 0.742 for 1, 3, and 5-year CSS. In the model, C-index was 0.703 for OS and 0.705 for CSS and showed good consistency.

Conclusion

Surgical treatment can improve the OS and CSS of patients with GIST-SLM. In addition, the combination with chemotherapy may be more favorable for the long-term survival of patients. Meanwhile, we constructed the nomograms for predicting OS and CSS at 1, 3, and 5-year, and validated them internally. Our model can contribute to clinical management and treatment strategy optimization.

The long-term efficacy of imatinib with hepatic resection or other local treatment for gastrointestinal stromal tumours liver metastases：a retrospective cohort study

BACKGROUND

The liver is the most common site of metastasis from gastrointestinal stromal tumours (GISTs). We aimed to evaluate imatinib (IM) combined with hepatic resection (HR) or other local treatments such as radiofrequency ablation (RFA) and transarterial chemoembolization (TACE), compared to IM monotherapy in long-term survival benefits in patients suffering from GIST liver metastases.

METHODS

Our research encompassed 238 patients diagnosed with liver metastases of GISTs from January 2002 to April 2022 at the XXX Hospital of XXX University. The oncological outcomes of concern included overall survival (OS), progression-free survival (PFS) and liver-specific PFS.

RESULTS

Of all 238 patients, 126 were treated with IM alone (IM group), 81 with IM combined with HR (IM+HR group), and 31 with IM combined with RFA/TACE (IM+RFA/TACE group). The median follow-up time was 44.83 months. The median OS in the IM group was 132.60 months and was not reached in either the IM+HR group or the IM+RFA/TACE group. The 10-year OS rate in the IM+HR group was significantly superior to the IM group and the IM+RFA/TACE group (91.9% vs. 61.1% vs. 55.2%, respectively, P=0.015), and the liver-specific PFS (P=0.642) and PFS (P=0.369) in the three groups showed a beneficial trend in the combined treatment group. Multivariate analyses showed that age ≤60 years (HR 0.280, P<0.001) and IM+HR (HR 0.361, P=0.047) were independently associated with better OS. Achieving no evidence of disease (NED) through surgical intervention was independently correlated with enhanced OS (HR 0.099, P=0.034), liver-specific PFS (HR 0.388, P=0.014), and PFS (HR 0.402, P=0.004).

CONCLUSIONS

In patients with GIST liver metastases, IM combined with HR might improve OS in selected patients compared with IM alone and IM combined with RFA/TACE. Achieving NED status with surgical treatment of patients results in significant prolonging of OS, liver-specific PFS and PFS.

Beyond squamous cell carcinoma: MRI appearance of uncommon anal neoplasms and mimickers

Anal cancer is an uncommon malignancy. In addition to squamous cell carcinoma, there are a variety of other less common malignancies and benign pathologies that may afflict the anal canal, with which abdominal radiologists should be familiar. Abdominal radiologists should be familiar with the imaging features that can help distinguish different rare anal tumors beyond squamous cell carcinoma and that can aid in diagnosis therefore help steer management. This review discusses these uncommon pathologies with a focus on their imaging appearance, management, and prognosis.

Development and validation of a prognostic nomogram for gastrointestinal stromal tumors in the postimatinib era: A study based on the SEER database and a Chinese cohort

BACKGROUND

After the standardization, recording and follow-up of imatinib use that significantly prolongs survival of gastrointestinal stromal tumors (GISTs), a comprehensive reassessment of the prognosis of GISTs is necessary and more conductive to treatment options.

METHODS

A total of 2185 GISTs between 2013 and 2016 were obtained from the Surveillance, Epidemiology, and End Results database and comprised our training (n = 1456) and internal validation cohorts (n = 729). The risk factors extracted from univariate and multivariate analyses were used to establish a predictive nomogram. The model was evaluated and tested in the validation cohort internally and in 159 patients with GIST diagnosed between January 2015 and June 2017 in Xijing Hospital externally.

RESULTS

The median OS was 49 months (range, 0-83 months) in the training cohort and 51 months (0-83 months) in the validation cohort. The concordance index (C-index) of the nomogram was 0.777 (95% CI, 0.752-0.802) and 0.7787 (0.7785, bootstrap corrected) in training and internal validation cohorts, respectively, and 0.7613 (0.7579, bootstrap corrected) in the external validation cohort. Receiver operating characteristic curves and calibration curves for 1-, 3-, and 5-year overall survival (OS) showed a high degree of discrimination and calibration. The area under the curve showed that the new model performed better than the TNM staging system. In addition, the model could be dynamically visualized on a webpage.

CONCLUSION

We developed a comprehensive survival prediction model for assessing the 1-, 3- and 5-year OS of patients with GIST in the postimatinib era. This predictive model outperforms the traditional TNM staging system and sheds light on the improvement of the prognostic prediction and the selection of treatment strategies for GISTs.

Gastrointestinal stromal tumors of the upper GI tract: population-based analysis of epidemiology, treatment and outcome based on data from the German Clinical Cancer Registry Group

BACKGROUND

Gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors. They are most frequently located in the stomach but are also found in the esophagus and the gastroesophageal junction (GEJ). Information regarding the prognostic factors associated with upper gastrointestinal GIST is still scarse.

METHODS

In this study, datasets provided by the German Clinical Cancer Registry Group, including a total of 93,069 patients with malignant tumors in the upper GI tract (C15, C16) between 2000 and 2016 were analyzed to investigate clinical outcomes of GIST in the entire upper GI tract.

RESULTS

We identified 1361 patients with GIST of the upper GI tract. Tumors were located in the esophagus in 37(2.7%) patients, at the GEJ in 70 (5.1%) patients, and in the stomach in 1254 (91.2%) patients. The incidence of GIST increased over time, reaching 5% of all UGI tumors in 2015. The median age was 69 years. The incidence of GIST was similar between males and females (53% vs 47%, respectively). However, the proportion of GIST in female patients increased continuously with advancing age, ranging from 34.7% (41-50 years) to 71.4% (91-100 years). Male patients were twice as likely to develop tumors in the esophagus and GEJ compared to females (3.4% vs. 1.9% and 6.7% vs. 3.4%, respectively). The median overall survival of upper gastrointestinal GIST was 129 months. The 1-year, 5-year, and 10-year OS was 93%, 79%, and 52% respectively. Nevertheless, tumors located in the esophagus and GEJ were associated with shorter OS compared to gastric GIST (130 vs. 111 months, p = 0.001). The incidence of documented distant metastasis increased with more proximal location of GIST (gastric vs. GEJ vs. esophagus: 13% vs. 16% vs. 27%) at presentation.

CONCLUSION

GIST of the esophagus and GEJ are rare soft tissue sarcomas with increasing incidence in Germany. They are characterized by worse survival outcomes and increased risk of metastasis compared to gastric GIST.

Update of epidemiology, survival and initial treatment in patients with gastrointestinal stromal tumour in the USA: a retrospective study based on SEER database

OBJECTIVES

An updated epidemiological analysis of gastrointestinal stromal tumour (GIST), the change of cancer-specific survival (CSS) and patterns of initial treatment are of interest.

DESIGN

A retrospective study using data from the Surveillance, Epidemiology and End Results (SEER) database.

SETTING AND PARTICIPANTS

A total of 5625 patients with GIST diagnosed between 2010 and 2019 were identified.

PRIMARY OUTCOME MEASURES

Age-standardised incidence rate (ASIR) and annual prevalence rate were calculated. SEER combined stage, period CSS rate and initial treatment were summarised. All the data were calculated by SEER*Stat software.

RESULTS

From 2010 to 2019, the ASIR of GIST increased from 0.79 to 1.02 per 100 000 person-years, with an increase of 2.4% annually. The increase was across age and sex subgroups. The prevalence trend was similar with the ASIR trend in each subgroup. The stage distributions were similar between different age groups, but varied among different primary tumour sites. More importantly, a stage shift from regional stage to localized stage at diagnosis was found, which may result in the improvement of CSS over years. Overall, the 5-year CSS rate of GIST was approximately 81.3%. Even for metastatic GIST, the rate exceeded 50%. Surgery was the most common treatment regimen for GIST, followed by surgery and systemic treatment. Whereas approximately 7.0% patients were undertreated, which was more pronounced among patients with distant and unknown stages.

CONCLUSIONS

The findings of this study suggest an improving early detection of GIST and an improving ability of accurate staging. Though most patients are effectively treated and perform good survivals, approximate 7.0% patients may be undertreated.

A New Online Dynamic Nomogram: Construction and Validation of a Predictive Model for Distant Metastasis Risk and Prognosis in Patients with Gastrointestinal Stromal Tumors

BACKGROUND

Gastrointestinal stromal tumor (GIST) is the most common sarcoma of the digestive tract, among which patients with distant metastases tend to have a poor prognosis. This study aimed to develop a model for predicting distant metastasis in GIST patients and to develop two models for monitoring overall survival (OS) and cancer-specific survival (CSS) in GIST patients with metastasis. This would allow us to develop an optimal, individualized treatment strategy.

METHODS

We reviewed demographic and clinicopathological characteristics data from 2010 to 2017 of patients diagnosed with GIST in the Surveillance, Epidemiology, and End Results (SEER) database. The data of the external validation group was reviewed from the Forth Hospital of Hebei Medical University. Univariate and multivariate logistic regression analyses were used to confirm the independent risk factors for distant metastasis in the GIST patients, and univariate and multivariate Cox regression analyses were performed to identify the independent prognostic factors for OS and CSS in the GIST patients with distant metastasis. Subsequently, three web-based novel nomograms were developed, which were evaluated by the receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

Of the 3639 patients who met the inclusion criteria, 418 (11.4%) had distant metastases. The risk factors for distant metastasis in GIST patients included sex, primary site, grade, N stage, tumor size, and mitotic count. For OS, the independent prognosis factors for GIST patients with metastasis included age, race, marital, primary site, chemotherapy, mitotic count, and metastasis at the lung, and for CSS, age, race, marital, primary site, and metastasis at the lung were the independent prognosis factors. Three web-based nomograms were constructed based on these independent factors, respectively. The ROC curves, calibration curves, and DCA were performed in the training, testing, and validation sets which confirmed the high accuracy and strong clinical practice power for the nomograms.

CONCLUSION

Population-based nomograms can help clinicians predict the occurrence and prognosis of distant metastases in patients with GIST, which may be helpful for clinicians to formulate clinical management and appropriate treatment strategies.

A Rare Case of Breast Metastatic Gastrointestinal Stromal Tumor

Gastrointestinal stromal tumor (GIST) is one of the most common spindle cell neoplasms of the alimentary system, and can arise anywhere along the gastrointestinal tract (GI). Its incidence rate is up to 22 cases per million, with a minor geographic variation. GIST is thought to originate from interstitial cell of Cajal, and its pathogenesis is related to molecular defects, such as KIT receptor tyrosine kinase or platelet-derived growth receptor alpha gene activation. While the majority of GISTs are known to show a benign disease course, metastases of high-grade forms to different organ systems have been seldom reported. We present a case with an unprecedented metastasis of GIST to the breast. The patient is a 62-year-old female with a history of the primary resection of GIST from the small intestine. Her disease course was initially complicated by multiple metastases, solely localized to the liver for which she had a living-donor liver transplant. The tumor harbored both KIT exon 11 and exon 17 mutation. Fourteen months post-transplant, the patient was found to have metastatic GIST on her breast biopsy. GIST metastasis to the breast is extremely rare. A consideration of this spindle cell neoplasm as a differential is recommended when clinical suspicion arises. The pathophysiology, current diagnostic tool, grading system, and treatment of this tumor are discussed.

Ten-Year Survivorship in Patients with Metastatic Gastrointestinal Stromal Tumors

INTRODUCTION

Patients developing metastatic gastrointestinal stromal tumors (mGIST) have heterogenous disease biology and oncologic outcomes; prognostic factors are incompletely characterized. We sought to evaluate predictors of 10-year metastatic survivorship in the era of tyrosine kinase inhibitor (TKI) therapy.

METHODS

We reviewed patients with mGIST treated at our Comprehensive Cancer Center from 2003 to 2019, including only patients with either mortality or 10 years of follow-up. Ten-year survivorship was evaluated with logistic regression.

RESULTS

We identified 109 patients with a median age of 57 years at mGIST diagnosis. Synchronous disease was present in 57% (n = 62) of patients; liver (n = 48, 44%), peritoneum (n = 40, 37%), and liver + peritoneum (n = 18, 17%) were the most common sites. Forty-six (42%) patients were 10-year mGIST survivors. Following mGIST diagnosis, radiographic progression occurred within 2 years in 53% (n = 58) of patients, 2-5 years in 16% (n = 17), and 5-10 years in 16% (n = 17), with median survival of 32, 76, and 173 months, respectively. Seventeen (16%) patients had not progressed by 10 years. Fifty-two (47%) patients underwent metastasectomy, which was associated with improved progression-free survival (hazard ratio 0.63, p = 0.04). In patients experiencing progression, factors independently associated with 10-year survivorship were age (odds ratio [OR] 0.96, p = 0.03) and time to progression (OR 1.71/year, p < 0.001).

CONCLUSIONS

Ten-year survivorship is achievable in mGIST in the era of TKIs and is associated with younger age and longer time to first progression, while metastasectomy is associated with longer time to first progression. The role of metastasectomy in the management of patients with disease progression receiving TKI therapy merits further study.

Umbilical metastasis as an initial presentation of gastrointestinal stromal tumour diagnosed on aspiration cytology

Umbilical metastasis is a rare event, with a majority being adenocarcinomas. Metastatic squamous cell carcinoma, small cell carcinoma, lymphoma, melanoma, and rarely malignant mesenchymal tumours like leiomyosarcoma can occur as umbilical nodules. These often emerge during a known malignancy, but once in a while they may be an initial presentation of an undetected tumour. An extensive literature search failed to reveal a case of gastrointestinal stromal tumour (GIST) with umbilical metastasis as an initial presentation. We believe that this is an exceptional phenomenon. The diagnosis may easily be missed considering the rarity of this occurrence. A history of primary diagnosis of GIST, when available, is helpful. Here we present cytological findings of metastatic GIST presenting as an umbilical lump, where the diagnosis was reached with the help of limited immunocytochemistry. A timely diagnosis is valuable for locating the primary and initiating surgical management, which may have survival benefits for the patient.

Hepatic metastases in gastrointestinal stromal tumors: oncologic outcomes with curative-intent hepatectomy, resection of treatment-resistant disease, and tyrosine kinase inhibitor therapy alone

BACKGROUND

Hepatic resection for metastatic GIST (mGIST) is often performed with either curative-intent or for tyrosine kinase inhibitor (TKI)-resistant lesions. The efficacy of hepatectomy for treatment-resistant lesions (TRL) is uncertain.

METHODS

We reviewed patients with liver-mGIST treated from 2003 to 2018. Oncologic outcomes including overall (OS), post-operative progression-free survival (PFS), and post-progression OS were evaluated using Kaplan-Meier and Cox proportional hazards modeling.

RESULTS

We identified n = 91 patients; 31 (34%) underwent curative-intent hepatectomy, 60 (66%) were initially managed with TKI alone, and 17 (19%) had resection of a TRL. The median follow-up for resected patients was 102 months (range 5-209 months) with 23 (25%) managed with a major hepatectomy. Patients having curative-intent hepatectomy had 72% 10-year OS following diagnosis of liver-mGIST, compared with 58% (P = 0.50) for TRL resection and 41% (P = 0.01) for non-resected patients. Curative-intent hepatectomy (HR 0.39, P = 0.03) and age (HR 1.04, P = 0.004) were independently associated with 10-year OS, but not TRL resection. TRL resection was not associated with improved post-progression OS compared to second-line TKI therapy (HR 0.61, P = 0.21).

CONCLUSIONS

Curative-intent hepatectomy is associated with improved OS in liver-mGIST. The oncologic benefit of resecting treatment-resistant liver-mGIST compared to second-line TKI therapy alone remains unclear in the era of multi-line TKI therapy.

Application of ultrasonography in predicting the biological risk of gastrointestinal stromal tumors

OBJECTIVES

To explore and establish a reliable and noninvasive ultrasound model for predicting the biological risk of gastrointestinal stromal tumors (GISTs).

MATERIALS AND METHODS

We retrospectively reviewed 266 patients with pathologically-confirmed GISTs and 191 patients were included. Data on patient sex, age, tumor location, biological risk classification, internal echo, echo homogeneity, boundary, shape, blood flow signals, presence of necrotic cystic degeneration, long diameter, and short/long (S/L) diameter ratio were collected. All patients were divided into low-, moderate-, and high-risk groups according to the modified NIH classification criteria. All indicators were analyzed by univariate analysis. The indicators with inter-group differences were used to establish regression and decision tree models to predict the biological risk of GISTs.

RESULTS

There were statistically significant differences in long diameter, S/L ratio, internal echo level, echo homogeneity, boundary, shape, necrotic cystic degeneration, and blood flow signals among the low-, moderate-, and high-risk groups (all p < .05). The logistic regression model based on the echo homogeneity, shape, necrotic cystic degeneration and blood flow signals had an accuracy rate of 76.96% for predicting the biological risk, which was higher than the 72.77% of the decision tree model (based on the long diameter, the location of tumor origin, echo homogeneity, shape, and internal echo) (p = .008). In the low-risk and high-risk groups, the predicting accuracy rates of the regression model reached 87.34 and 81.82%, respectively.

CONCLUSIONS

Transabdominal ultrasound is highly valuable in predicting the biological risk of GISTs. The logistic regression model has greater predictive value than the decision tree model.

Surgical resection of intraorbital metastasis of a gastrointestinal stromal tumor resistant to chemotherapy

Purpose

We present a case of a gastrointestinal stromal tumor (GIST) metastasis of the rectal primary resisting chemotherapy to the right orbit 15 years after excision of the primary lesion.

Observations

A 79-year-old man was diagnosed with rectal GIST at the age of 65 years and underwent rectal amputation. He underwent hepatectomy for GIST liver metastases at the age of 69 years and pericardiectomy for GIST pericardial metastases at 72 years of age. At the age of 79 years, positron emission tomography-computed tomography revealed the possibility of liver metastasis and metastasis to the right orbit of 10 mm in size. Magnetic resonance imaging revealed a well-circumscribed mass of 10 mm × 12 mm in the deep medial rectus muscle of the right orbit, which was referred to our department for ophthalmic examination. The latter revealed only mild abduction disorder in the right eye. Although chemotherapy was initiated, the tumor gradually increased, causing exophthalmos in the right eye, visual field impairment due to optic nerve exclusion, and decreased visual acuity. Due to repeated multiple metastases, the patient underwent right orbital exenteration and free flap reconstruction at the age of 83 years for radical cure. Pathological examination revealed c-Kit positive, CD34 positive, S100 protein minority positive, MIB-1 positive rate of 10% or more, and α-SMA negative, and the diagnosis was intraorbital metastasis of GIST.

Conclusions and importance

Orbital metastases in GISTs are extremely rare, and there is no established standard treatment. Therefore, a comprehensive decision must be made based on the final treatment goal and the patient's background when selecting treatment.

Clinical Trial Eligibility Criteria and Recently Approved Cancer Therapies for Patients With Brain Metastases

Brain metastases cause significant morbidity and mortality in patients with advanced cancer. In the era of precision oncology and immunotherapy, there are rapidly evolving systemic treatment options. These novel therapies may have variable intracranial efficacy, and patients with brain metastases remain a population of special interest. Typically, only patients with stable, asymptomatic and/or treated brain metastases are enrolled in clinical trials, or may be excluded altogether, particularly in the setting of leptomeningeal carcinomatosis. Consequently, this leads to significant concerns on the external validity of clinical trial evidence to real-world clinical practice. Here we describe the current trends in cancer clinical trial eligibility for patients with brain metastases in both early and late phase trials, with a focus on targeted and immunotherapies. We evaluate recent newly FDA approved therapies and the clinical trial evidence base leading to approval. This includes analysis of inclusion and exclusion criteria, requirements for baseline screening for brain metastases, surveillance cerebral imaging and incorporation of trial endpoints for patients with brain metastases. Finally, the use of alternative sources of data such as real-world evidence with registries and collaborative studies will be discussed.

[A CASE OF PRIMARY ADRENAL LYMPHOMA SUSPECTED AS ADRENAL METASTATIC TUMOR FROM GASTROINTESTINAL STROMAL TUMOR]

We present a case of 75 year's old man for whom small bowel resection was performed for a small intestinal tumor diagnosed as a gastrointestinal stromal tumor (GIST) with KIT exon 11 mutation and intermediate Miettinen risk. Computed tomography (CT) 18 months after surgery showed a right adrenal mass measuring 20 mm in size. Imatinib therapy couldn't show the tumor shrinkage, and the adrenal mass increased up to 37 mm in size 3 months later. He was referred to our department for further examination and treatment. We diagnosed this adrenal tumor as imatinib resistant GIST or adrenal primary malignancy and performed retroperitoneal laparoscopic right adrenalectomy. The pathological diagnosis was diffuse large B-cell lymphoma (DLBCL) not GIST and PET-CT revealed systemic metastasis of DLBCL one month later after surgery. Six courses of R-CHOP therapy achieved a complete response.

Gastroduodenal intussusception as a rare cause of pancreatitis in a young female Ugandan: A case report

Introduction and importance

Gastroduodenal intussusceptions are rare and usually secondary to gastric lesions acting as the lead point. Gastrointestinal stromal tumors (GISTs) commonly occur in the stomach (40–60%). Other gastric tumors include; adenocarcinomas, leiomyomas, lymphomas among others. When gastric tumors act as lead points in gastroduodenal intussusception, pancreatitis may arise due to compression of the ampulla of Vater or pancreatic head. Gastroduodenal intussusception may mimic other inflammatory upper gastrointestinal conditions leading to delays in early diagnosis and timely intervention.

Case presentation

A twenty three year old female with gastroduodenal intussusception secondary to a gastric body GIST with associated pancreatitis. This gastroduodenal mass was initially diagnosed as a pancreatic head echo-complex mass by ultrasound. Confirmatory preoperative diagnosis was made after doing contrasted abdominal computed tomography (CT) scan and upper gastrointestinal endoscopy. Open gastric wedge resection was done. Patient had uneventful recovery and was discharged on the fifth postoperative day.

Clinical discussion

Gastroduodenal intussusceptions have non-specific clinical features that may lead to delays in making the correct diagnosis. CT scan is a good imaging modality for diagnosing this condition but access is limited in low resource settings. Resection of the organic cause after reducing the intussusception leads to resolution of the symptoms caused by the intussusception, the GIST and the resultant pancreatitis.

Conclusion

Gastroduodenal intussusception is rare and may present with nonspecific clinical features. Pancreatitis may arise due to the compression effects on the ampulla of Vater or pancreatic head. A high index of suspicion is key in making a timely diagnosis.

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Gastroduodenal intussusception is rare and may cause pancreatitis by it's direct pressure effects on the ampulla of vater.

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This condition may mimic pancreatitis leading to a delay in early surgical intervention.

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Abdominal ultrasound scan in experienced hands, abdominal CT scan with or without Oesophagogastroduodenoscopy is diagnostic.

Humeral metastasis as the only recurrence of a 5-year resected gastrointestinal stromal tumor: a case report

INTRODUCTION

Gastrointestinal stromal tumors represent the most frequently encountered primary mesenchymal tumors. Whereas the liver and the peritoneum are known to be the preferential metastasis sites, no therapeutic standard has yet been established for the management of bone metastases because of their very low incidence. We report a unique example of a single humerus metastasis of a jejunal gastrointestinal stromal tumor.

CASE PRESENTATION

We report the case of a 72-year-old European woman whose jejunal gastrointestinal stromal tumor was resected in 2013 and treated during the following 3 years with imatinib (400 mg daily). In 2018, she developed a single humeral bone lesion that was identified as a gastrointestinal stromal tumor metastasis. After 7 months of imatinib intake, reconstructive surgery was performed. Pathologists confirmed the satisfactory histological regression and assessed the complete tumor resection. The patient is still on imatinib maintenance therapy, with no recurrence reported so far. She fully recovered the upper limb function after following an appropriate rehabilitation program.

DISCUSSION

Current literature and published case reports indicate that bones are one of the rarest locations of gastrointestinal stromal tumor metastasis (about 1%), with occurrence mainly in the spine. Patients initially diagnosed with gastrointestinal stromal tumor of the small intestine and stomach are more likely to suffer from bone metastasis, compared with other gastrointestinal stromal tumor locations. The median overall survival rate is higher for patients with isolated bone metastasis compared with those having liver metastasis. Metastasis occurs on average 4 years after the primary, but it may take up to 20 years, emphasizing the need for long-term clinical and radiological monitoring. Although specific guidelines for such cases have not yet been established, we suggest that a multimodal concerted approach involving surgery or radiotherapy associated with tyrosine kinase inhibitor intake should be considered.

CONCLUSION

Bones are one of the rarest locations of gastrointestinal stromal tumor metastasis. A multidisciplinary collaboration was set up to allow conservative surgery of our patient after several months of imatinib treatment. A year and a half later, the patient is still in complete remission. This specific case supports the concept of an intermediate stage between local and oligometastatic disease that should be managed with a curative aim, as much as possible.

Metastatic Liver Tumors in Surgical Pathology: Impact of Contemporary Diagnostic and Therapeutic Paradigms in a Tertiary Care Center

We analyzed metastatic liver tumors received in the department of pathology in a tertiary care center over a 3-year period. There were 509 metastatic liver tumors; counterintuitively, there were as many resections (235 cases) as biopsies (274 cases). This unexpected finding reflects contemporaneous organ-specific paradigms for diagnosis and management of metastatic liver disease in oncologic practice, and the association of our practice with a National Cancer Institute-designated comprehensive cancer center with expertise and specialization in liver surgery. We receive a large number of resections for metastatic liver tumors because metastasectomy from a variety of primary tumors is associated with improved overall, and in many instances, disease-free, long-term survival. Metastatic colorectal carcinomas, metastatic neuroendocrine tumors, and metastatic gastrointestinal stromal tumors constituted 78% of resections because the largest body of literature and cumulative experience exists for these lesions. In contrast, breast carcinomas and pancreatic carcinomas, which are the next common metastatic liver tumors were biopsied but rarely resected, because metastasectomy is not the standard of care for these tumors. Immunohistochemistry was performed in less than a quarter of the total number of cases (23%), because the primary tumor site was known in the vast majority of cases. Of the 42 cases with unknown primary tumor, it was elucidated in 50% of the cases by immunohistochemical and clinical work-up. Of the cases with known primary tumor, immunohistochemistry was performed mostly in metastatic breast, colon, and lung carcinomas. In these cases, biomarker analyses provided additional information relevant to clinical management.

Imatinib-resistant gastrointestinal stromal tumors in the era of second- and third-line tyrosine kinase inhibitors: Does surgical resection have a role?

BACKGROUND

Imatinib resistance is associated with a poor prognosis in patients with gastrointestinal stromal tumors. Although novel tyrosine kinase inhibitors have improved outcomes in imatinib-resistant gastrointestinal stromal tumors, the role of resection remains unclear. We sought to investigate factors predictive of overall and progression-free survival in patients with imatinib-resistant gastrointestinal stromal tumors.

METHODS

A query of our prospectively maintained Comprehensive Cancer Center registry was performed from 2003 to 2019 for patients with imatinib-resistant gastrointestinal stromal tumors. Clinicopathologic characteristics and medical and surgical treatments were collected; overall survival and progression-free survival after imatinib-resistance were analyzed with Kaplan-Meier and Cox proportional hazards modeling.

RESULTS

A total of 84 patients developed imatinib resistance at a median age of 59 years. Median time to imatinib resistance after diagnosis and overall survival after imatinib resistance was 50 and 51 months, respectively. After being diagnosed with imatinib resistance, 17 (20%) patients underwent resection. On multivariable analysis, resection after imatinib resistance was independently associated with improved progression-free survival (hazard ratio 0.50; P = .027) but not overall survival (hazard ratio 0.62; P = .215). Similar findings were found on subgroup analysis of patients treated with second-line sunitinib (n = 71).

CONCLUSION

Long-term survival can be achieved in patients who develop imatinib-resistant gastrointestinal stromal tumors. Surgical resection of imatinib-resistant gastrointestinal stromal tumors is associated with improved progression-free survival and should be considered in selected patients.

Surgical Management of Metastatic Gastrointestinal Stromal Tumors

OPINION STATEMENT

Treatment with the tyrosine kinase inhibitor (TKI), imatinib is the standard first-line treatment for metastatic gastrointestinal stromal tumors (GISTs). Unfortunately, acquired c-kit mutations cause secondary resistance to imatinib in a median of 18-24 months. Sunitinib and regorafenib are multi-kinase inhibitors that can be used as second-line or third-line therapy in imatinib-resistant or -intolerant GISTs, respectively. Ripretinib (a switch-control tyrosine kinase inhibitor) has recently been approved for fourth-line treatment in metastatic GIST. The TKI avapritinib has been approved for metastatic GIST harboring the imatinib-resistant PDGFRA exon 18 mutation. Although TKI therapies have revolutionized the treatment of metastatic GISTs, they cannot cure metastatic GISTs. Therefore, cytoreductive surgery is of considerable interest and has been accordingly investigated. Retrospective non-randomized studies demonstrated the feasibility and safety of continuous TKI therapy and surgical resection. Most studies demonstrate response to TKI therapy, completeness of resection, extent of disease, and surgical complexity as predictors of outcomes. Most TKIs can be stopped shortly before surgery and restarted shortly after. There is no known survival benefit from debulking operations or R2 resections and this should not be considered. However, debulking/palliative surgery may be necessary for patients with complications of hemorrhage, pain, or intestinal obstruction. SDH-deficient GISTs have an indolent natural history despite metastatic disease and may be another uncommon subgroup that would benefit from surgical debulking (R2 resection). At the time of operation, care should be taken to avoid tumor rupture. After surgical resection, patients should resume tyrosine kinase inhibitor (TKI) therapy as soon as possible and be monitored for disease progression. In all patients with metastatic GIST, the decision to pursue metastasectomy for GIST should be made in a multidisciplinary setting and be individualized according to patient age, comorbidities, functional status, symptoms, mutation status, extent of disease, completeness of resection, TKI response, and goals of the patient.

Gastrointestinal stromal tumor with multisegmental spinal metastases as first presentation: A case report and review of the literature

BACKGROUND

Gastrointestinal stromal tumor (GIST) usually originates in the stomach, followed by the small intestine, rectum, and other parts of the gastrointestinal tract. The most common sites of metastasis are the liver and peritoneum, whereas spinal metastases from GIST are extremely rare.

CASE SUMMARY

We found a case of GIST with the first presentation of multilevel spinal metastases involving the thoracic and lumbar vertebrae. A 61-year-old Chinese man presented to our clinic because of pain in his lower back and hip for 10 d without cause. Subsequently, computed tomography (CT) and magnetic resonance imaging (MRI) revealed abnormal signals in the vertebral appendages of T12 and L4 accompanied by spinal canal stenosis, which was considered as tumor metastasis. As there were no metastases to vital organs, posterior thoracic and lumbar spinal decompression + adnexal mass resection + pedicle internal fixation was adopted to achieve local cure and prevent nerve compression. The results of histopathological studies were consistent with the metastasis of GIST. No local recurrence or new metastases were found at the 6-mo follow-up at the surgical site. The patient has no neurological symptoms at present. It is worth mentioning that a rectal mass was found and surgically removed 1 mo after the patient was discharged from hospital, and the pathological diagnosis of the mass was GIST.

CONCLUSION

By reviewing 26 previously reported cases of spinal metastasis in GIST, it was found that spinal metastasis of GIST has become more common in recent years, so the possibility of early spinal metastasis should be recognized. CT and MRI are of great value in the diagnosis of spinal metastatic tumors, and pathological biopsy is the gold standard for the diagnosis of metastatic tumors. It is safe and feasible to treat isolated spinal metastasis in GIST by excising metastatic masses, decompressing the spinal canal, and stabilizing the spine.

A novel nomogram for predicting liver metastasis in patients with gastrointestinal stromal tumor: a SEER-based study

Background

Liver metastasis (LIM) of gastrointestinal stromal tumor (GIST) is associated with poor prognosis. The present study aimed at developing and validating nomogram to predict LIM in patients with GIST, thus helping clinical diagnosis and treatment.

Methods

The data of GIST patients derived from Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2016, which were then screened by univariate and multivariate logistic regression for the construction of LIM nomogram. The model discrimination of LIM nomogram was evaluated by concordance index (C-index) and calibration plots, while the predictive accuracy and clinical values were measured by decision curve analysis (DCA) and clinical impact plot. Furthermore, we validated predictive nomogram in the internal testing set.

Results

A total of 3797 patients were enrolled and divided randomly into training and validating groups in a 3-to-1 ratio. After logistic regression, the significant variables were sex, tumor location, tumor size, N stage and mitotic rate. The calibration curves showed the perfect agreement between nomogram predictions and actual observations, while the DCA and clinical impact plot showed the clinical utility of LIM nomogram. C-index of the nomogram was 0.812. What’s more, receiver operating characteristic curves (ROC) also showed good discrimination and calibration in the training set (AUC = 0.794, 95% CI 0.778–0.808) and the testing set (AUC = 0.775, 95% CI 0.748–0.802).

Conclusion

The nomogram for patients with GIST can effectively predict the individualized risk of liver metastasis and provide insightful information to clinicians to optimize therapeutic regimens.

Bone Metastases of Gastrointestinal Stromal Tumor: A Review of Published Literature

Background

With the occurrence and improvement of immunohistochemistry and other pathological diagnostic techniques, gastrointestinal stromal tumor (GIST) has been gradually recognized. With the prolonged survival of patients with GISTs, reports about the bone metastasis of GIST increased. However, the knowledge of GISTs is rather limited due to its very low incidence.

Methods

Cochrane and Medline database (via PubMed) were searched in July 2019 with related keywords to acquire the literature related to the bone metastasis of GIST. Then, the literature was reviewed and references were also scanned to identify the possible related reports. Study data comprising age, sex, primary location, metastasis interval time, immunohistochemistry index, management and prognosis were recorded and analyzed.

Results

Forty-five patients with bone metastases of GIST, with a mean age of 61.09 years, were included. The small intestine and stomach were the most common primary sites, followed by the rectum. Patients with small intestine primary sites had bone metastases that occurred earlier than the bone metastases stomach and rectum primary sites. The spine was the most common site of bony metastases. The mean survival time after GIST diagnosis was more than 64.02 months. Patients younger than 60 years old had a worse prognosis than those older than 60 years old. Furthermore, patients with spinal involvement had a worse prognosis than those without spinal involvement. Surgical interventions combined with targeted therapies guaranteed a better prognosis.

Conclusion

Bone metastasis of GIST, which mainly occurs in the spine, is rather rare. Patients with GISTs of the small intestine and stomach suffered from bone metastasis more frequently and earlier than patients with GISTs in other primary sites. Age, sex, primary tumor location, treatment mode for the primary lesions and metastases, and spine involvement may be potential factors that affect the prognosis of GIST patients with bone metastases.

Stereotactic ablative radiotherapy for bone metastasis of gastrointestinal stromal tumor: Case report and review of the literature

Background

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. These tumors are rare and only make bone metastases at a rate of 5%.

Case summary

A 31-year-old male with a GIST presented with solitary bone metastasis at the right iliac bone. We performed stereotactic ablative radiotherapy (SABR) and achieved excellent local control. Herein, our case is presented, and a short review of the literature is carried out.

Conclusion

SABR should be considered as a treatment option in GIST with bone metastasis.

The epithelioid gastrointestinal stromal tumor with pulmonary metastasis: A rare case report and literature review

RATIONALE

Available literature states that the histological subtype of the gastrointestinal stromal tumor (GIST) with pulmonary metastasis is often spindle cell type. To our knowledge, this is the first report of the GIST with pulmonary metastasis of very uncommon epithelioid subtype.

PATIENT CONCERNS

We report a 63-year-old male presenting with the symptom of bloodstained sputum without obvious inducement. The patient had no chest pain, low back pain, fatigue, fever or night sweats symptoms.

DIAGNOSES

Combined chest digital radiography and the history of the patient who presented with the colon GIST of the epithelioid subtype two years ago that the mass may be a metastasis tumor. Combined with morphological and immunohistochemical staining results, a pathological diagnosis of the GIST with pulmonary metastasis was considered.

INTERVENTIONS

Right lobectomy and partial upper lobectomy were performed.

OUTCOMES

The patient had not experienced any noticeable symptom and recurrent tumors at 6 months follow-up.

LESSONS

We report a rare case of the GIST with pulmonary metastasis of epithelioid subtype. This case is of great significance to the pathologist's clinical work. For pathologists, if an epithelioid tumor in the lung is found, it is necessary to check whether the gastrointestinal tract also has the tumor, which may be an epithelioid GIST with pulmonary metastasis.

Establishment and Verification of Synchronous Metastatic Nomogram for Gastrointestinal Stromal Tumors (GISTs): A Population-Based Analysis

Aim

Assess the risk of synchronous metastasis and establish a nomogram in patients with GISTs.

Methods

Surveillance, Epidemiology and End Results database (2004-2014) was accessed. With the logistic regression model as the basis, a nomogram was constructed.

Results

7,256 target patients were contained in our study. The nomogram discrimination for mGIST prediction revealed that tumor size contributed most to synchronous metastasis, followed by lymph nodes, extension, pathologic grade, tumor location, and mitotic count. C-index values of predictions were 0.821 (95% CI, 0.805-0.836) and 0.815 (95% CI, 0.800-0.831), and Brier score were 0.109 and 0.112 in training and validation group, respectively. The value of area under the ROCs were 0.813 (p < 0.001) in the primary cohort and 0.819 (p < 0.001) in the validation cohort. Through the calibration curves (as seen in the figures), nomogram prediction proved to have excellent agreement with actual metastatic diseases.

Conclusion

A new nomogram was created that can evaluate synchronous metastatic diseases in patients with GISTs.