The analysis of prognostic factors of primary small intestinal gastrointestinal stromal tumors with R0 resection: A single-center retrospective study

OBJECTIVE

We aim to assess factors that affect overall survival in patients with primary small intestinal gastrointestinal stromal tumors (GISTs) who had undergone R0 resection.

METHOD

A retrospective analysis reviewed the data of 82 consecutive confirmed GIST patients at a single medical center in China from January 2012 to June 2020. The survival curve was estimated using the Kaplan-Meier method, and independent prognostic factors were confirmed using the Cox regression model.

RESULTS

A total of 82 patients were included in the study: 42 men and 40 women, the mean age was 59 years old (23-83 years old). Tumors were commonly found in the jejunum (46.3%), ileum (20.7%), and duodenum (32.9%). The median tumor size was 6.0 cm (range: 1.0-15.0 cm). The number of mitoses per one 50 high-power field was used to define the mitotic rates. In our present study, 56 patients presented a mitotic rate ≤5 (68.3%) and 26 patients showed a rate >5 (31.7%) at the time of diagnosis. All patients accepted tumor resection without lymph node resection. The positivity rate was 97.6% for CD117, 96.3% for delay of germination 1, 65.9% for CD34, 6.1% for S-100, and 59.8% for smooth muscle actin using immunohistochemistry. Tumor size, tumor rupture, Ki67 index, mitotic index, and postoperative imatinib were independent prognostic factors for small intestinal GISTs.

CONCLUSIONS

In this study, larger tumor size, high Ki67 index, high mitotic index, the occurrence of tumor rupture, and use of imatinib were independent unfavorable prognostic indicators.

CT Radiomics for the Preoperative Prediction of Ki67 Index in Gastrointestinal Stromal Tumors: A Multi-Center Study

Purpose

This study established and verified a radiomics model for the preoperative prediction of the Ki67 index of gastrointestinal stromal tumors (GISTs).

Materials and Methods

A total of 344 patients with GISTs from three hospitals were divided into a training set and an external validation set. The tumor region of interest was delineated based on enhanced computed-tomography (CT) images to extract radiomic features. The Boruta algorithm was used for dimensionality reduction of the features, and the random forest algorithm was used to construct the model for radiomics prediction of the Ki67 index. The receiver operating characteristic (ROC) curve was used to evaluate the model’s performance and generalization ability.

Results

After dimensionality reduction, a feature subset having 21 radiomics features was generated. The generated radiomics model had an the area under curve (AUC) value of 0.835 (95% confidence interval(CI): 0.761–0.908) in the training set and 0.784 (95% CI: 0.691–0.874) in the external validation cohort.

Conclusion

The radiomics model of this study had the potential to predict the Ki67 index of GISTs preoperatively.

Ki-67 labelling index is related to the risk classification and prognosis of gastrointestinal stromal tumours: a retrospective study

BACKGROUND AND AIMS

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the digestive tract with malignant potential. The current risk classification standard is unable to accurately evaluate the invasiveness and clinical outcomes of GISTs. Ki-67 labelling index (LI) may be an effective indicator in assessing tumour invasiveness and prognosis, however, its exact value in GISTs is still uncertain. The aims of our study were to evaluate the correlation of the Ki-67 LI and clinicopathological features of GISTs and to assess the potential value of the Ki-67 LI in GISTs classification and prognosis.

METHODS

The clinical, pathological and prognostic data were collected and analysed to identify the independent influential factors of GISTs risk stratification and the predictors of GISTs prognosis.

RESULTS

The Ki-67 LI was significantly associated with the clinicopathological features of tumour progression (P<0.05). It was an independent influential factor of GISTs risk classification (odds ratio: 1.322; 95% confidence interval: 1.031-1.696) (P=0.028), and the area under the curve (AUC) value of the Ki-67 LI on the discrimination ability of GISTs risk stratification was 0.906 (P<0.001). The optimal cutoff value of the Ki-67 LI was 6% (sensitivity of 87.5% and specificity of 76.2%), and patients with Ki-67 LI≥6% exhibited significantly poorer progression-free survival (PFS) than those with Ki-67 LI<6% (P<0.001). The AUC value of the Ki-67 LI for predicting PFS in postoperative patients was 0.813 (P=0.03).

CONCLUSIONS

The Ki-67 LI has appreciated value to predict the risk grade and prognosis of GISTs. Patients with Ki-67 LI≥6% are prone to recurrence and metastasis after operation and may need a close follow-up.

Ki-67 labeling index may be a promising indicator to identify "very high-risk" gastrointestinal stromal tumor: a multicenter retrospective study of 1022 patients

We sought to determine whether Ki-67 labeling index (LI) was an independent prognostic factor for gastrointestinal stromal tumor (GIST). A multicenter cohort of 1022 patients undergoing surgical resection of primary GIST between August 2004 and October 2015 was retrospectively analyzed. Immunohistochemical analysis was performed to evaluate expression of Ki-67 in their paraffin-embedded tissue samples. The optimal cutoff value of Ki-67 LI was determined as 6% by receiver operating characteristics curve analysis. Multivariate analysis showed that Ki-67 LI was a significant predictor of overall survival (OS) (hazard ratio: 1.793; 95% confidence interval, 1.240-2.593; P=.002). When stratified by modified National Institutes of Health classification, it was still independently associated with OS in high-risk and non-high-risk patients (P=.001 and P=.055, respectively). Of note, the prognostic significance of Ki-67 LI was also maintained when stratified by tumor size, mitotic index, tumor site, and histological subtype (all Ps<.05). In addition, high-risk patients with Ki-67 LI >6% exhibited a significantly poorer OS rate than those with Ki-67 LI ≤6% (53.6% versus 88.7%, respectively; P=.001). The area under the receiver operating characteristics curve for Ki-67 LI was higher than that of modified National Institutes of Health classification component in high-risk patients (P=.029). Therefore, Ki-67 LI is a promising predictor of outcome in GIST, especially in high-risk patients, and it may have important clinical utility in identifying "very high-risk" patients for rational targeted therapy.

Ki-67 Labeling Index can be used as a Prognostic Marker in Gastrointestinal Stromal Tumor: A Systematic Review and Meta-Analysis

Purpose

The aim of this study was to investigate the prognostic relevance of the Ki-67 labeling index (LI) in gastrointestinal stromal tumor (GIST) through a systematic review, meta-analysis and diagnostic test accuracy review.

Method

The study included 1,967 GIST cases from 24 eligible studies. We investigated the correlation between high Ki-67 LI and survival and the proper criteria for high Ki-67 LI. In addition, a diagnostic test accuracy review was conducted to evaluate the predictive role of high Ki-67 LI for higher risk of tumor recurrence.

Results

A high Ki-67 LI was significantly correlated with worse disease-free survival (DFS) (hazard ratio [HR] 3.658, 95% confidence interval [CI] 2.687-4.979, p<0.001) and overall survival (OS) (HR 3.730, 95% CI 2.819-4.936, p<0.001). With regard to DFS and OS, the subgroup with a cutoff value of >4% for high Ki-67 LI had a higher HR than the subgroup with a ≤4% cutoff. In the diagnostic test accuracy review, a high Ki-67 LI was significantly correlated with higher risk of tumor recurrence (pooled sensitivity = 0.44, pooled specificity = 0.87, area under the curve on the summary receiver operating characteristic curve = 0.656).

Conclusions

Our results showed that a high Ki-67 LI was significantly correlated with worse prognosis and higher risk of tumor recurrence in GIST. Further prospective studies of the prognostic role of Ki-67 LI are necessary prior to application in clinical practice.

Ki67 as a prognostic factor for long-term outcome following surgery in gastrointestinal stromal tumors

OBJECTIVE

This study aimed to examine the value of Ki67 expression along with other potential prognostic factors for predicting overall survival and disease-free survival in patients with gastrointestinal stromal tumors who underwent curative resection.

PATIENTS AND METHODS

Sixty-eight histologically confirmed and operated patients with gastrointestinal stromal tumors were included. Clinical and follow-up data were retrieved from medical records and patients were contacted at the end of the study. The effects of certain clinical and histopathological parameters on survival outcomes were examined.

RESULTS

Sixty-eight patients were followed for a mean duration of follow-up of 2923.3 patient-months. Twelve deaths (17.6%), seven metastasis (10.3%), and two local recurrences (2.9%) occurred. Overall survival was 102.5 months [95% confidence interval (CI), 88.3-116.8] and disease-free survival was 91.8 months (95% CI, 76.5-107.2). Multivariate analyses identified a high Ki67 index (≥ 10%) as an independent predictor of both poor overall survival (hazard ratio, 4.8; 95% CI 1.2-19.2; P=0.027) and poor disease-free survival (hazard ratio, 15.3; 95% CI, 4.7-50.2).

CONCLUSION

A high Ki67 expression seems to be a useful prognostic factor that would aid in predicting disease course in gastrointestinal stromal tumors. These findings deserve further investigation in larger studies.