Retroperitoneal Extragastrointestinal Stromal Tumors Have a Poor Survival Outcome: A Multicenter Observational Study

Clinicopathological characteristics and long-term prognosis of peritoneal and retroperitoneal gastrointestinal stromal tumors

BACKGROUND

Peritoneal and retroperitoneal gastrointestinal stromal tumors (PRGISTs) are exceedingly uncommon, and their clinicopathological characteristics and long-term prognosis remain unreported. Therefore, our objective is to analyze these aspects of patients with PRGISTs using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Patients diagnosed with PRGISTs and small intestine stromal tumors (SISTs) between 2000 and 2019 were included in the study. Differences between groups were compared using Chi-square tests. Kaplan-Meier analysis and Cox proportional hazards models were used to evaluate overall survival (OS) and cancer-specific survival (CSS).

RESULTS

A total of 3817 patients were enrolled, with 3513 diagnosed with SISTs and 304 with PRGISTs. Compared to SISTs, PRGISTs patients were older, with larger tumors, higher mitotic rates, and greater risk of lymph node (5.3%) and distant (30.6%) metastasis (P < 0.001). Multivariate analysis identified N stage and mitotic rate as risk factors for distant metastasis in PRGISTs. In comparison to SISTs, PRGISTs patients exhibited a significantly worse OS (hazard ratio [HR] 1.83, 95% confidence interval [CI] 1.57-2.15, P < 0.001) and CSS (HR 2.11, 95% CI 1.73-2.58, P < 0.001). Subgroup analyses by age, sex, surgical status, chemotherapy, and marital status consistently demonstrated poorer OS and CSS for PRGISTs patients compared to SISTs patients (P < 0.05). The 1-, 3-, 5-, and 10-year OS rates for PRGISTs patients were 77.9%, 61.6%, 51.6%, and 32.8%, respectively, with corresponding CSS rates of 84.5%, 71.7%, 63.3%, and 49.0%. Multivariate Cox regression analysis identified age, race, surgical status, and mitotic rate as risk factors influencing OS, while race, surgical status, and mitotic rate were identified as risk factors affecting CSS.

CONCLUSIONS

In comparison to SISTs, PRGISTs patients exhibit distinct clinicopathological features and have a worse prognosis. However, surgical intervention can improve the prognosis of PRGISTs patients.

Investigation of unfavorable prognostic factors for survival in Chinese patients with gastric gastrointestinal stromal tumors

Background

Gastrointestinal stromal tumor (GIST) was very rare in the gastrointestinal (GI) tract. Most GISTs were asymptomatic at early stage. Therefore, it was of great significance to explore the prognostic factors of patients with GIST. This investigation aimed to assess the unfavorable prognostic factors for overall survival (OS) and disease-free survival (DFS) in 106 Chinese patients with GISTs.

Methods

A total of 106 Chinese patients, including 68 women and 38 men, with confirmed gastric GIST treated at the General Hospital of Ningxia Medical University in China from 2012 to 2018 were included. Kaplan-Meier analysis and Cox regression models were applied to evaluate the unfavorable prognostic risk factors for survival.

Results

Kaplan-Meier analysis demonstrated that blood type A was significantly related to poor OS (P=0.01), and tumor invasion, higher Ki-67 index, synchronous gastric cancer (GC), and tumor necrosis were significantly associated with poor DFS (all P<0.05). Multivariate analysis further demonstrated that blood type A was a significant independent prognostic factor with both OS and DFS (both P<0.05). Synchronous GC and age ≥60 years were also significant independent prognostic factor for DFS (both P<0.05).

Conclusions

Blood type A, age ≥60 years, and synchronous GC were unfavorable prognostic factors for survival in Chinese patients with gastric GISTs. The mechanism underlying the prognostic role of these factors warrants further investigation.

Gastrointestinal Stromal Tumors (GISTs) Mimicking Primary Ovarian Tumors or Metastasizing to the Ovaries: A Systematic Literature Review

Background: Gastrointestinal stromal tumors (GISTs) are a rare neoplasm, sometimes mimicking primary ovarian tumors (OTs) and/or metastasizing to the ovaries (M-OT). We performed a systematic literature review (SLR) of OTs and M-OTs, investigating differences in recurrence-free and overall survival. Methods: Our SLR was performed according to PRISMA guidelines, searching in Pubmed, Scopus, and Web of Science databases from inception until 21 April 2024. Results: Overall, 59 OTs (Group 1) and 21 M-OTs (Group 2) were retrieved. The absence of residual disease after surgery was achieved significantly in a higher percentage of patients with Group 1 GISTs (91.5%) compared with Group 2 GISTs (57.1%). Chemotherapy was more frequently administered to Group 2 patients (33% vs. 0%). Recurrence and deaths for disease were significantly more frequent in Group 2 than Group 1 cases (54.5% vs. 6.8%, and 37.5% vs. 9.8%, respectively). Conclusions: GISTs can rarely mimic primary ovarian cancers or even more rarely metastasize to the ovaries. Group 1 GISTs occurred in younger women, were not associated with elevated tumor markers, and had a better prognosis. In contrast, Group 2 GISTs occurred in older women, may exhibit elevated tumor markers, and presented a worse prognosis. However, no significant statistical difference for survival between the two studied groups was detected. Computed tomography scans can define the size of GISTs, which correlate to stage and prognostic risk classes. The gold standard treatment is complete surgical resection, which was achieved in almost all cases of Group 1 GISTs and in half of Group 2. Histopathology and immunohistochemistry are essential for the final diagnosis and guide chemotherapy treatment.

Survival analysis of extragastrointestinal stromal tumors based on the SEER database: a population-based study

BACKGROUND

Extragastrointestinal stromal tumors (EGISTs) are rare mesenchymal neoplasms that originate outside the gastrointestinal tract. However, the population-level survival analysis of EGIST remains poorly grasped. Therefore, we aimed to analyze the survival of EGIST patients using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

All patients diagnosed with GIST and EGIST between 2000 and 2019 were identified through utilization of the SEER database. Missing data were handled using multiple imputation methodology. Kaplan-Meier analyses and Cox proportional hazard models were employed to assess the influence of demographic and clinical characteristics on both overall survival (OS) and cancer-specific survival (CSS).

RESULTS

A total of 13,330 patients were enrolled in the study, comprising 12,627 diagnosed with GIST and 703 with EGIST. EGIST patients demonstrated significantly poorer OS [hazard ratio (HR) 1.732, 95% confidence interval (CI) 1.522-1.970, P < 0.001] and CSS (HR 2.167, 95% CI 1.821-2.577, P < 0.001) compared to GIST patients. The mean 1-year, 3-year, 5-year, and 10-year OS rates for EGIST patients were 78.3%, 61.9%, 50.5%, and 32.5%, respectively, with corresponding mean CSS rates of 84.3%, 70.8%, 61.3%, and 46.5%. Multivariate Cox regression analysis identified age, race, sex, grade, size, and surgical type as independent risk factors for OS in EGIST patients, while age, sex, year of diagnosis, grade, surgical type, and radiation therapy were identified as independent risk factors for CSS. Patients with EGIST who underwent surgical treatment exhibited significantly higher 5-year OS rates (49.0% vs. 39.9%, P = 0.035) and CSS rates (63.9% vs. 53.0%, P = 0.028) compared to those who did not undergo surgery.

CONCLUSIONS

EGIST patients have a poorer prognosis compared to GIST patients; however, surgical treatment has been shown to improve the prognosis.

Retroperitoneal extra gastrointestinal stromal tumor: A case report

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors. Researchers do not know precisely what leads to GISTs, but genetic mutations play an important role. These mutations have no apparent cause. GISTs are usually asymptomatic tumors, although GI bleeding and weight loss can occur. CT is preferred for investigating potential GISTs.

CASE PRESENTATION

A 36-year-old unmarried Syrian female came to the hospital complaining of recurrent abdominal pain. CT revealed a large mass occupying a significant portion of the left hypochondrium and the lower part of the epigastrium. The tumor exceeded the median line to the right, pressing on the mesenteric vessels and the intestinal loops below. Immunohistochemistry results showed moderate positivity to CD117 and CD34, which were compatible with the diagnosis of GIST. The entire mass was excised. Physicians performed CT follow-ups every three months for 18 months, and no evidence of recurrence was observed.

DISCUSSION

Extragastrointestinal GISTs are a rare subtype of GISTs that occur outside the GI tract. GISTs previously used to be misdiagnosed as leiomyoma, leiomyosarcoma, leiomyoblastoma, and schwannoma. Treatment depends on surgery with adjuvant therapy tyrosine kinase inhibitors. Follow-up is recommended as the risk of recurrence is high.

CONCLUSION

We recommend that GIST, as an extremely rare tumor, should be considered in the differential diagnoses of masses that occur in the extra-intestinal region. Usually, patients need surgery with lymph node resection. However, this was not needed in our case.

Primary extra-gastrointestinal stromal tumor of retroperitoneum: Clinicopathologic characteristics and prognosis of six cases

Aim

This study investigates the clinicopathological features and prognostic genic biomarker factors of primary retroperitoneal extra-gastrointestinal stromal tumors (EGISTs).

Methods

The clinicopathological data of six patients with primary retroperitoneal EGIST were analyzed, including cell type (epithelioid or spindle), mitoses, and the presence of intratumoral necrosis and hemorrhage. Mitoses were counted and summed from 50 high power fields (HPFs). Mutations of exons 9, 10, 11, 13, 14, and 17 of the C-kit genes and those of exons 12 and 18 of the PDGFRA gene were examined. Follow-up was performed via telephone, and all outpatient records were reviewed. The last follow-up date was February 2022, the median follow-up was 27.5m and the postoperative status, medication, and survival of the patients were recorded.

Result

The patients were treated with radical intent. Four cases (patients 3, 4, 5, and 6) underwent multivisceral resection for encroachment on the adjacent viscera. The postoperative pathological results demonstrated that all biopsy specimens were negative for S-100 and desmin, and positive for DOG1 and CD117. Additionally, four patients (case 1, 2, 4, and 5) were positive for CD34, four (case 1, 3, 5, and 6) were positive for SMA, four (case 1, 4, 5, and 6) had >5/50 HPFs, and three (case 1, 4, and 5) had Ki67 >5%. According to the modified National Institutes of Health (NIH) guidelines, all patients were graded as high-risk cases. By exome sequencing, exon11 mutations were detected in the six patients, while exon10 mutations were detected in two cases (patients 4 and 5). The median follow-up time was 30.5 (11-109) months, with only one fatality at 11 months.

Conclusion

Retroperitoneal EGIST is a rare mesenchymal tumor that is difficult to distinguish from other retroperitoneal tumors. To diagnose this highly malignant tumor, low-threshold suspicion is necessary, and Kit and PDGFRA gene mutations should be routinely tested to confirm the diagnosis and guide subsequent treatment.

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.

Clinical Features of Extragastrointestinal Stromal Tumor Compared with Gastrointestinal Stromal Tumor: A Retrospective, Multicenter, Real-World Study

Objective

This study aimed to compare the tumor characteristics and long-term outcomes between EGIST and GIST. The confounding function was applied to improve the result credibility in the case of small sample size. Design, Setting, and Participants. This cohort study enrolled 55 patients with EGIST who underwent surgery and were selected from four high-volume hospitals in China and 221 GIST patients who were collected from one of the four hospitals between January 2006 and September 2017. We used propensity score matching (PSM) and subgroup analysis to compare EGIST with GIST in terms of prognosis. The confounding function was used for sensitivity analysis to reduce unmeasured confounding.

Results

We matched 43 patients in each of the GIST and EGIST groups by PSM. We compared EGIST data with GIST data to explore the prognostic factors between them. In the multivariate Cox regression model, tumor location of EGIST was negatively correlated with overall survival (after PSM: HR, 4.32; 95% CI, 1.22–15.26) or disease-free survival (after PSM: HR, 9.79; 95% CI, 2.22–43.31), which was also intuitively shown in the Kaplan–Meier survival curves (all P values < 0.05). In the subgroup analysis, EGIST with high risk factors had a worse prognosis than GIST. In unmeasured confounding analysis, the overall curve tends to show all combinations of c(0) of c(1) up to 2.0, none of which would bring the corrected relative risk to 1 for OS and DFS. Conclusions and Relevance. EGIST was associated with worse prognosis compared with GIST patients, particularly in EGIST patients with high risk factors, while there was a similar prognosis without those high risk factors.