Management of gastrointestinal stromal tumors: looking beyond the knife. An update on the role of adjuvant and neoadjuvant imatinib therapy. J Gastrointest Cancer. 2012;43:547-552. [PMID: 22847491 DOI: 10.1007/s12029-012-9423-0]

Extra gastrointestinal stromal tumor in the recto-vesical pouch: A case report and literature review

Introduction

Extra-gastrointestinal stromal tumors (EGISTs) are rare mesenchymal tumors located outside the gastrointestinal tract, and exhibit the same phenotypic and morphological profile of gastrointestinal stromal tumors (GISTs).

Case report

We report the case of a 20-year-old male patient consulted for chronic discomfort in the hypogastric region. Abdominal ultrasound and abdomino-pelvic CT scan identified a retro-vesical mass measuring 16 × 9 cm. He underwent an exploratory laparotomy and a total resection of the mass R0. The histopathological panel of the surgical specimen confirmed the diagnosis of EGIST.

Clinical discussion

The primary localization in the recto-vesical pouch of EGIST is a very rare entity. Their clinical and radiological presentations are unusual, and their definitive diagnosis is largely based on immunohistochemistry staining.

Conclusion

the origin of extra gastrointestinal stromal tumors EGIST can remain unclear.

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Extra gastrointestinal stromal tumors (EGISTs) are very rare primary entities that develop outside the digestive tract.

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Their primary localization in the recto-vesical pouch is a very rare entity.

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Their definitive diagnosis is largely based on immunohistochemistry staining.

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The only accepted treatment for non-metastatic EGISTs is a complete surgical resection.

Diagnosis and Endoscopic Treatment of Gastrointestinal Stromal Tumors Arising from Esophagus

Aim: The primary purpose of this study was to investigate the diagnosis and endoscopic treatment of gastrointestinal stromal tumors (GISTs) arising from esophagus. Materials and Methods: From January 2013 to December 2017, 16 cases of GISTs of esophagus were retrospectively identified from a total of >3000 GISTs treated in our center. Demographic characteristics, clinical data, endoscopic therapy outcomes, histopathology, and follow-up were analyzed. Results: The mean age of the patients was 53 years (range 35-71 years), mostly female (56.3%). Seven tumors were in the lower esophagus, five in the middle esophagus, and one in the upper esophagus. The most common symptom was abdominal discomfort (8/16; 50.0%), followed by acid reflux (6/16; 37.5%). All of the patients underwent CT scan, gastroscopy, and/or endoscopic ultrasound. Two patients were diagnosed with esophageal GISTs with a preoperative endoscopic biopsy. Tumors were resected completely in all patients by endoscopic surgery. The median operating time was 85 minutes (range 28-153 minutes), and the average tumor size was 11.6 mm (range 6-21 mm). Postoperative histopathology demonstrated esophageal GISTs were positive for CD117 and CD34. The mean length of postoperative hospital stay was 4.7 days (range 2-7 days). The median postoperative follow-up duration was 28 months (range 1-59 months). Conclusion: Endoscopic treatment seems to be safe and effective for tumors size <20 mm in diameter. However, long-term prospective randomized controlled trials are further needed.

Bromodomain and extraterminal domain inhibitor enhances the antitumor effect of imatinib in gastrointestinal stromal tumours

In gastrointestinal stromal tumours (GISTs), the function of bromodomain-containing 4 (BRD4) remains underexplored. BRD4 mRNA abundance was quantified in GISTs. In the current study, we investigated the role of BRD4 in GISTs. Our results show a significant enhancement in BRD4 mRNA and a shift from very low-risk/low-risk to high-risk levels as per NCCN specifications. Overexpression of BRD4 correlated with unfavourable genotype, nongastric location, enhanced risk and decreased disease-free survival, which were predicted independently. Knockout of BRD4 in vitro suppressed KIT expression, which led to inactivation of the KIT/PI3K/AKT/mTOR pathway, impeded migration and cell growth and made the resistant GIST cells sensitive to imatinib. The expression of KIT was repressed by a BRD4 inhibitor JQ1, which also induced myristoylated-AKT-suppressible caspases 3 and 9 activities, induced LC3-II, exhibited dose-dependent therapeutic synergy with imatinib and attenuated the activation of the PI3K/AKT/mTOR pathway. In comparison with their single therapy, the combination of JQ1/imatinib more efficiently suppressed the growth of xenografts and exhibited a reduction in KIT phosphorylation, a decrease in Ki-67 and in the levels of phosphorylated PI3K/AKT/mTOR and enhanced TUNEL staining. Thus, we characterized the biological, prognostic and therapeutic implications of overexpressed BRD4 in GIST and observed that JQ1 suppresses KIT transactivation and nullifies the activation of PI3K/AKT/mTOR, providing a potential strategy for treating imatinib-resistant GIST through dual blockade of KIT and BRD4.

Laparoscopic resection of gastrointestinal stromal tumors: Does laparoscopic surgery provide an adequate oncologic resection?

Gastrointestinal stromal tumors (GISTs) are rare tumors of the GI tract. Surgical resection remains the mainstay of non-metastatic disease. However, the ability to provide an adequate oncologic resection using laparoscopic surgery is still an area of debate. This is a thorough review of the current literature, looking particularly at the use of laparoscopic surgery for larger GISTs and the long-term oncologic outcomes compared to the results of open surgery. Laparoscopic resections provide an adequate oncologic result for GISTs of all sizes, including those greater than 5 cm in size.

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.

Usefulness of laparoscopic side-to-side duodenojejunostomy for gastrointestinal stromal tumors located at the duodenojejunal junction

BACKGROUND

Surgery for gastrointestinal stromal tumor (GIST) at the duodenojejunal junction is a technically challenging and difficult procedure because of the anatomical complexity. When it comes to laparoscopic surgery, it is more challenging than open surgery. This study aimed to introduce our laparoscopic procedure and to evaluate its clinical implication by comparing with open procedures.

METHOD

Between 2003 and 2013, 19 patients underwent segmental resection for a GIST at the duodenojejunal junction: laparoscopic segmental resection with side-to-side duodenojejunostomy (n = 8) and open surgery (n = 11). Clinicopathological findings, operation details, and postoperative outcomes were compared.

RESULTS

Both groups were comparable in demographics and clinicopathological characteristics. Postoperative hospital stay of the laparoscopic group (6.3 days) was significantly shorter than the open group (15.7 days, P = 0.008) while no significant differences were observed regarding estimated blood loss, operation time, and morbidity. All patients in both groups underwent curative resection without operative mortality. Two patients experienced recurrence after open surgery whereas none of the patients after laparoscopic duodenojejunostomy had recurrence with a median follow-up period of 36 months.

CONCLUSION

Laparoscopic segmental resection with side-to-side duodenojejunostomy for a GIST at the duodenojejunal junction is a safe, feasible, and effective alternative to open approach, providing benefits of minimally invasive surgery.

Treatment Results of Small Intestinal Gastrointestinal Stromal Tumors Less than 10 cm in Diameter: A Comparison between Laparoscopy and Open Surgery

Purpose

To evaluate the technical feasibility and oncologic safety, we assessed the short-term and long-term outcomes of laparoscopic resection of the small bowel gastrointestinal stromal tumors smaller than 5 cm by comparing those of open surgery by subgroup analysis based on tumor size.

Materials and Methods

From November 1993 to January 2011, 41 laparoscopic resections were performed among the 95 patients who underwent resection of small intestine ≤10 cm in diameter. The clinicopathologic features, perioperative outcomes, recurrences and survival of these patients were reviewed.

Results

The postoperative morbidity rates were comparable between the 2 groups. Laparoscopic surgery group showed significantly shorter operative time (P=0.004) and duration of postoperative hospital stay (P<0.001) than open surgery group and it was more apparent in the smaller tumor size group. There were no difference in 5-year survival for the laparoscopic surgery versus open surgery groups (P=0.163), and in 5-year recurrence-free survival (P=0.262). The subgroup analysis by 5 cm in tumor size also shows no remarkable differences in 5-year survival and recurrence-free survival.

Conclusions

Laparoscopic resection for small bowel gastrointestinal stromal tumors of size less than 10 cm has favorable short-term postoperative outcomes, while achieving comparable oncologic results compared with open surgery. Thus, laparoscopic approach can be recommended as a treatment modality for patients with small bowel gastrointestinal stromal tumors less than 10 cm in diameter.