Preoperative imatinib treatment in patients with advanced gastrointestinal stromal tumors: patient experiences and systematic review of 563 patients

Neoadjuvant Imatinib in Locally Advanced Gastrointestinal Stromal Tumors (GISTs) is Effective and Safe: Results from a Prospective Single-Center Study with 108 Patients

BACKGROUND

Neoadjuvant imatinib is considered for gastrointestinal stromal tumors (GISTs) when decreased tumor size provides less extensive surgery and higher R0 resection rates. This study evaluates the effectivity and safety of neoadjuvant imatinib for large or locally advanced GIST.

PATIENTS AND METHODS

From the prospective database of the Dutch GIST Consortium, all patients who underwent surgery after neoadjuvant imatinib at our center between 2009 and 2022 were selected. Independent and blinded assessment of surgical strategy was performed by two surgeons, based on anonymized computed tomography (CT) scans before and after neoadjuvant imatinib.

RESULTS

Of 113 patients that received neoadjuvant imatinib, 108 (95%) [mean age 61.6, standard deviation (SD) 11.5, 54% male] underwent a GIST resection. Of all GISTs, 67% was localized in the stomach and 25% in the duodenum or small intestine. In 74% of the patients with GIST, a KIT exon 11 mutation was found. Decreased tumor size was seen in 95 (88%) patients. Having a KIT exon 11 mutation [odds ratio (OR) 5.64, 95% confidence interval (CI) 1.67-19.1, p < 0.01] or not having a mutation (OR 0.19, 95% CI 0.04-0.89, p = 0.04) were positive and negative predictive values for partial response, respectively. In 55 (51%) patients, there was deescalation of surgical strategy after neoadjuvant imatinib. Surgical complications were documented in 16 (15%) patients (n = 8, grade II; n = 5, grade IIIa; n = 3, grade IIIb) and R0 resection was accomplished in 95 (89%) patients. The 5-year disease-free and overall survival were 80% and 91%, respectively.

CONCLUSION

This study shows that neoadjuvant imatinib is effective and safe for patients with large or locally advanced GIST.

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.

Medical Oncological Treatment for Patients with Gastrointestinal Stromal Tumour (GIST) - a Systematic Review

BACKGROUND

Chemotherapy is ineffective in treating patients with Gastrointestinal Stromal Tumour (GIST). However, several types of tyrosine kinase inhibitors have been investigated since the approval of imatinib in 2001. The purpose of this report was to systematically review studies on the efficacy of neoadjuvant, adjuvant, and lifelong medical oncological treatment of GIST.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed throughout the review process. The protocol was submitted to the International prospective register of systematic reviews database (ID 251724). A systematic literature search was performed, including phase II- and III studies of biological treatment, reporting on treatment effect in patients with GIST.

RESULTS

Of 308 identified publications, 42 studies were included in this review.

CONCLUSION

This review gives an overview of the existing evidence for approved lines of oncological treatments and potential alternatives for patients with GIST in the neoadjuvant-, adjuvant- and life-long setting.

Computer-aided diagnosis of gastrointestinal stromal tumors: a radiomics method on endoscopic ultrasound image

PURPOSE

The purpose of our study is to propose a preoperative computer-aided diagnosis system based on a radiomics method to differentiate gastrointestinal stromal tumors (GISTs) of the higher-risk group (HRG) from those of the lower-risk group (LRG) on endoscopic ultrasound (EUS) images.

MATERIALS AND METHOD

Gastro-EUS (G-EUS) images of four different risk level GISTs were collected from 19 hospitals. The datasheet included 168 case HRG GISTs and 747 case LRG GISTs. A radiomics method with image segmentation, feature extraction, feature selection and classification was developed. Here 439 radiomics features were firstly extracted, and then, the least absolute shrinkage selection operator (lasso) model with a tenfold cross-validation and 31 bootstraps was used to reduce the dimension of feature sets. Finally, random forest was applied to establish the classification model.

RESULTS

The proposed model differentiated 32 case HRG GISTs from 149 case LRG GISTs. Result for the testing set achieved the area under the receiver operating characteristic curve of 0.839, the accuracy of 0.823, the sensitivity of 0.813 and the specificity of 0.826.

CONCLUSION

The model could increase preoperative diagnostic accuracy and provide a valuable reference for the doctors.

Combined Therapy of Gastrointestinal Stromal Tumors

Radical surgery is the mainstay of therapy for primary resectable, localized gastrointestinal stromal tumors (GIST). Nevertheless, approximately 40% to 50% of patients with potentially curative resections develop recurrent or metastatic disease. The introduction of imatinib mesylate has revolutionized the therapy of advanced (inoperable and/or metastatic) GIST and has become the standard of care in treatment of patients with advanced GIST. This article discusses the proper selection of candidates for adjuvant and neoadjuvant treatment in locally advanced GIST, exploring the available evidence behind the combination of preoperative imatinib and surgery.

The predictive value of preoperative 18F-fluorodeoxyglucose PET for postoperative recurrence in patients with localized primary gastrointestinal stromal tumour

OBJECTIVES

To assess the potential value of preoperative ¹⁸F-FDG PET to predict postoperative recurrence of solitary localized primary gastrointestinal stromal tumour (GIST) after radical resection.

METHODS

A total of 46 patients with primary GIST who received preoperative ¹⁸F-FDG PET and underwent complete resection without neoadjuvant therapy were retrospectively studied. PET findings, including ring-shaped uptake and intense uptake, were compared with Joensuu risk grades using Fisher's exact test. The prognostic value of the preoperative clinico-imaging variables-age ≥60 years, male, ring-shaped uptake, intense uptake, tumour size >5 cm, heterogeneous CT attenuation and lower gastrointestinal origin-and Joensuu high risk for recurrence-free survival was evaluated using log-rank test and multivariate Cox regression analysis.

RESULTS

Ring-shaped uptake and intense uptake were significantly associated with Joensuu high risk. Univariate analysis showed that ring-shaped uptake, intense uptake, size >5 cm and Joensuu high risk were significantly associated with inferior recurrence-free survival. Multivariate analysis showed that ring-shaped uptake (P = 0.004) and Joensuu high risk (P = 0.021) were independent adverse prognostic factors of postoperative recurrence.

CONCLUSIONS

Ring-shaped uptake on preoperative ¹⁸F-FDG PET may be a potential predictor of postoperative tumour recurrence of localized primary GISTs.

KEY POINTS

• Clinical course of resectable solitary localized primary GISTs varies widely. • Ring-shaped uptake is an independent adverse prognostic factor of postoperative recurrence. • Preoperative ¹⁸ F-FDG PET may help predict postoperative recurrence of GISTs.