Gastrointestinal stromal tumors: current diagnosis, biologic behavior, and management

Transvaginal resection of a gastrointestinal stromal tumor of the rectum: a case report

BACKGROUND

The most common curative treatment for gastrointestinal stromal tumors (GISTs) is local excision. For rectal GISTs, however, local excision is difficult because of the anatomical features of the rectum. The optimal surgical approach is still under debate, and less invasive methods are desired. We herein report a case of transvaginal resection of a rectal GIST in a young woman.

CASE PRESENTATION

A 21-year-old woman was diagnosed with a resectable GIST in the anterior rectal wall and underwent transvaginal tumor resection. The posterior vaginal wall was incised, revealing the tumor fully covered by the rectal mucosa. The rectal adventitia and muscular layer were incised, and the tumor was resected en bloc without rupture. The postoperative course was favorable, and the patient was discharged on postoperative day 12. No findings consistent with recurrence were present 6 months postoperatively.

CONCLUSION

Transvaginal tumor resection is a treatment option as a minimally invasive procedure for GISTs in the anterior rectal wall in female patients.

Surgical management of a locally advanced jejunal stromal tumor: A case report of a challenging condition

INTRODUCTION AND IMPORTANCE

Locally advanced jejunal stromal tumors stand as a captivating and relatively rare entity, garnering attention for several reasons. Their inaccessible location by conventional endoscopy poses a diagnostic challenge. Further, treatment decisions necessitate a multidisciplinary approach, compounded by the absence of high-level evidence studies.

CASE PRESENTATION

A 54-year-old patient was admitted to our surgical department with abdominal pain and chronic anemia. Abdominal CT imaging confirmed the presence of a non-metastatic sizable jejunal tumor. The patient underwent laparotomy, revealing a locally advanced jejunal tumor contracting the ileum and the ascending colon. A monobloc oncological resection was performed, followed by the restoration of digestive continuity. Anatomopathological analysis delineated a locally advanced Stromal Tumor with a high risk of recurrence. The patient underwent a course of tyrosine kinase inhibitors for 3 years, with no reported recurrence during the subsequent 3-year follow-up.

DISCUSSION

Locally advanced jejunal stromal tumors are rare. Most patients present with unspecific symptoms. Diagnosis remains challenging due to their intricate anatomical location. Decisions regarding management must be deliberated within a multidisciplinary framework, tailored to each patient's unique characteristics. While combined therapeutic modalities have demonstrated efficacy in recent studies, prudence is advised given the heightened incidence of both short and long-term complications.

CONCLUSION

In the absence of randomized controlled trials, the management of locally advanced jejunal stromal tumors underscores the imperative of multidisciplinary collaboration in treatment deliberations. A wide, sometimes mutilating excision is only permissible if it is complete.

Prognostic importance of mitosis quantification and PHH3 expression in oral epithelial dysplasia

Oral epithelial dysplasia (OED) is diagnosed and graded using a range of histological features, making grading subjective and challenging. Mitotic counting and phosphohistone-H3 (PHH3) staining have been used for the prognostication of various malignancies; however, their importance in OED remains unexplored. This study conducts a quantitative analysis of mitotic activity in OED using both haematoxylin and eosin (H&E)-stained slides and immunohistochemical (IHC) staining for PHH3. Specifically, the diagnostic and prognostic importance of mitotic number, mitotic type and intra-epithelial location is evaluated. Whole slide images (WSI) of OED (n = 60) and non-dysplastic tissue (n = 8) were prepared for analysis. Five-year follow-up data was collected. The total number of mitosis (TNOM), mitosis type and intra-epithelial location was manually evaluated on H&E images and a digital mitotic count performed on PHH3-stained WSI. Statistical associations between these features and OED grade, malignant transformation and OED recurrence were determined. Mitosis count increased with grade severity (H&E: p < 0.005; IHC: p < 0.05), and grade-based differences were seen for mitosis type and location (p < 0.05). The ratio of normal-to-abnormal mitoses was higher in OED (1.61) than control (1.25) and reduced with grade severity. TNOM, type and location were better predictors when combined with histological grading, with the most prognostic models demonstrating an AUROC of 0.81 for transformation and 0.78 for recurrence, exceeding conventional grading. Mitosis quantification and PHH3 staining can be an adjunct to conventional H&E assessment and grading for the prediction of OED prognosis. Validation on larger multicentre cohorts is needed to establish these findings.

Concurrence of Adenomyoepithelioma of the Breast and Gastrointestinal Stromal Tumor of the Stomach: A Case Report and Review of the Literature

Adenomyoepithelioma (AME) of the breast and gastrointestinal stromal tumors (GISTs) are rare benign (primarily) tumors observed in the breast and gastrointestinal tract, respectively. The coexistence of both of these rare tumors is extremely rare; therefore, the author describes the clinical presentation and pathophysiological findings of such a unique case in this study. A 56-year-old female patient with no medical history presented with a substantial right breast lump, severe nausea, and vomiting, and suffered from iron deficiency anemia. Radiological observation and a right breast excisional biopsy diagnosed the patient with AME associated with ductal carcinoma in situ (DCIS). Endoscopy and a CT scan of the stomach revealed the existence of GIST. This is the first reported case of concurrence of a huge mass of AME and GIST in a patient. Histological and immunohistochemistry tests using p63, SMA, calponin, and Ki67 markers for the breast tumor and DOG-1, CD34, and CD117 markers for the gastric tumor revealed the non-invasive benign state. The patient had a right breast mastectomy with a negative resection margin. AME of the breast and GIST pose diagnostic challenges due to their erratic morphological characteristics and can cause misinterpretation drawn solely from radiological tests. Effective and accurate diagnostics require assessing the histological and immunohistochemistry findings of the tumor to identify the invasiveness of the neoplasm and the associated risk levels. This report, thus, creates awareness among clinicians and pathologists for the consideration of such possibilities and, therefore, conducts the necessary diagnostics and prophylactic treatments.

Is single incision laparoscopic surgery (SILS) for gastric gastrointestinal stromal tumor (GIST) dependent on the location of the tumor?

BACKGROUND

We compared the surgical outcomes of single-incision laparoscopic surgery (SILS) and conventional laparoscopic surgery (CLS) for gastric gastrointestinal stromal tumor (GIST).

METHODS

We performed single-incision gastric wedge resection on prospectively-enrolled 15 consecutive patients with gastric GIST between November 2020 and April 2022 in a single tertiary center. The early perioperative outcomes of these patients were compared to those of patients who underwent CLS. The indications did not differ from those for conventional laparoscopic procedures for gastric GIST.

RESULTS

In total, 30 patients were assigned to the SILS (n = 15) and CLS (n = 15) groups. There were no significant differences in the estimated blood loss and intraoperative blood transfusion between the SILS and CLS groups. There were no intraoperative complications or conversions to multiple-port or open surgery in the SILS group. Proximally located tumors were more commonly treated with CLS than with SILS (P = 0.045). GISTs located in the greater curvature were more commonly treated with SILS than with CLS, although the difference was not statistically significant (P = 0.08). The mean incision length in the SILS group was 4.1 cm shorter than that in the CLS group (3.2 ± 0.7 and 7.3 ± 5.2 cm, respectively, P = 0.01). The postoperative analgesic dose was significantly lower in the SILS than in the CLS group (0.4 ± 1.4 and 2.1 ± 2.3, respectively P = 0.01). Also, the duration of postoperative use of analgesic was shorter in SILS than in CLS (0.4 ± 0.7 and 2.0 ± 1.8, respectively, P = 0.01). There were no significant differences in the early postoperative complications between the groups.

CONCLUSIONS

SILS is as safe, feasible, and effective for the treatment of gastric GIST as CLS with comparable postoperative complications, pain, and cosmesis. Moreover, SILS can be considered without being affected by the type or location of the tumor.

Gastrointestinal Stromal Tumors: Recurrence and Survival Analysis of 49 Patients

Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor originating from the gastrointestinal tract and have a broad spectrum of clinicopathological features affecting disease management regarding the treatment modalities. Methods: A retrospective study of 49 patients who underwent surgery for gastrointestinal tumors between 2008 and 2016 was conducted. Clinical, pathological, and immunohistochemical features of patients with and without recurrence were statistically analyzed. Results: Twenty-nine (59.1%) patients had gastric; 16 (32.6%) had small intestinal; 3 (6.1%) had mesenteric; and 1 (2.2%) had rectal GISTs. Microscopic tumor necrosis and tumor ulceration were also significant for disease recurrence (P = 0.005, P = 0.049). High-risk patients according to Miettinen's risk classification were more likely to develop a recurrence (P < 0.001). Additionally, high-grade tumors were also a risk factor for recurrence (P < 0.001). Ki-67 levels were available in 40 patients and the mean Ki-67 level was 16.8 in patients with recurrence, which was a significant risk factor in regression analysis (HR: 1.24, 95%, CI: 1.08-1-43). Five-year disease-free survival rates of non-gastric and gastric GISTs were 62.3% and 90%, respectively (P = 0.044). Conclusion: Larger tumors and higher mitotic rates are more likely to develop recurrence. High Ki-67 levels were also associated with recurrence.

Primary extragastrointestinal stromal tumors of the prostate: A case report and literature review

Gastrointestinal stromal tumors (GISTs) are the main stromal tumors of the digestive tract. Extragastrointestinal stromal tumors (EGISTs) typically originate outside the gastrointestinal tract; are not associated with the stomach or intestinal walls; and are mainly derived from the mesentery, peritoneum, posterior peritoneum, bladder, and scrotum. However, EGISTs from the prostate are rare. Here, we present a case of EGIST that passed off in the prostate of a 62-year-old man. The patient undergoes transrectal guided trans-perineal prostate puncture, and pathological reports suggest a GIST. Tumor cells are spindle-shaped, and no obvious neoplastic necrosis is seen in the sections. Immunohistochemical results are robustly positive for CD117, DOG-1, and CD34 expression. The patient had a good prognosis after treatment with imatinib, no recurrence and no metastases after six months of follow-up, and the prognosis was good. This article also provides a literature review and discussion of the treatment of EGISTs.

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.

Long-term prognosis of small gastric gastrointestinal stromal tumors with high histological grade: a longitudinal nested cohort study

BACKGROUND AND AIMS

Gastrointestinal stromal tumors (GIST) are mostly seen in the stomach. Clinical data on GISTs ≤ 2 cm with > 5 mitosis/50 HPFs are limited. This study aimed to analyze small GISTs with high histological grades to gain a more comprehensive understanding of their clinical characteristics with long-term follow-up.

METHODS

This was a nested cohort study of patients with gastric GISTs ≤ 2 cm and > 5 mitosis/50 HPFs. Individuals with endoscopically resected gastric specimens diagnosed as GISTs between January 2008 and July 2019 were enrolled. We analyzed baseline clinicopathological characteristics, perioperative characteristics, risk of recurrence, and metastasis during follow-up.

RESULTS

A total of 55 patients diagnosed with gastric GISTs ≤ 2 cm and > 5 mitosis/50 HPFs were enrolled. The mean tumor size was 1.6 ± 0.4 cm (median 1.7 cm, range 0.8-2.0 cm). ESD was performed in 33 patients (60.0%) and EFTR in 22 patients (40.0%). Mean mitotic figures were 8.9/50 HPFs. Postoperative bleeding in one patient (1.8%) was the only severe adverse event. The mean follow-up period was 61.2 ± 33.9 months (median 53 months, range 13-133 months). Five patients (5/55, 9.1%) received additional therapies, including partial gastrectomy and adjuvant Imatinib. Only two patients (2/55, 3.6%) showed signs of recurrence. We observed no significant difference regarding baseline clinical characteristics and recurrence among GISTs with mitosis < 10/50 HPF and ≥ 10/50 HPF. No patient had signs of metastasis during follow-up.

CONCLUSION

Endoscopic resection of gastric GISTs ≤ 2 cm with > 5 mitosis/50 HPFs has a low risk of recurrence and metastasis in the long term. Endoscopic resection of GISTs is safe and feasible.

Gastrointestinal stromal tumor in the fourth portion of the duodenum does not express the CD117: A case report

Introduction

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract.

Presentation of case

54-year-old woman with a history of phyllodes tumor of the left breast he patient was admitted to our hospital for management of retroperitoneal soft tissue tumor, attached to the fourth portion of the duodenum, opposite the head of the pancreas. The patient underwent a large excision of the tumor, the duodenojejunal flexure, and the third and fourth portions of the duodenum along with the head of the pancreas. The histopathological examination confirmed the presence of a spindlecell mesenchymal proliferation. These cells do not express CD117, but they express DOG1. A PDGFRA mutation was identified later. The final diagnosis was duodenal GIST.

Discussion

few cases of GIST in the fourth portion of the duodenum had been reported in the literature. PDGFRA mutation is identified as GISTs tumorigenesis to 15% of cases, and the diagnosis of GISTs is not based solely on the expression of the protein Kit.

Conclusion

the molecular biology examinations are very helpful in the direction of the correct diagnosis in case of negative staining for CD117.

Laparoscopic resection of a gastrointestinal stromal tumor that recurred more than 15 years after surgery using lighted ureteral catheters: A case report

A 69-year-old woman underwent abdominoperineal resection for a gastrointestinal stromal tumor (GIST) of the rectum 15 years ago. She received adjuvant chemotherapy for 8 years. Seven years later, abdominal computed tomography revealed a soft-tissue shadow in the left lower abdomen, and fluorodeoxyglucose uptake was observed at the same site on positron emission tomography. The recurrence of GIST was suspected, and laparoscopic resection was performed. Laparoscopy showed that the tumor was located at the retroperitoneum near to the descending colon and invaded the left ovarian vessels. It also made contact with the left ureter; however, lighted ureteral catheters enabled us to identify and preserve the left ureter. An immunohistochemical examination revealed the recurrence of GIST. Recurrence may become apparent 15 years or more after GIST surgery, and, thus, a long-term follow-up is required. Lighted ureteral catheters were useful for identifying the ureter and preventing ureteral injury in a recurrent case suspected of invading the ureter.

The Diagnosis of Small Gastrointestinal Subepithelial Lesions by Endoscopic Ultrasound-Guided Fine Needle Aspiration and Biopsy

Endoscopic ultrasonography (EUS) has been widely accepted in the diagnosis of all types of tumors, especially pancreatic tumors, lymph nodes, and subepithelial lesions (SELs). One reason is that the examination can provide a detailed observation, with tissue samples being immediately obtained by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). Many SELs are detected incidentally during endoscopic examinations without symptoms. Most SELs are mesenchymal tumors originating from the fourth layer, such as gastrointestinal stromal tumors (GISTs), leiomyomas, and schwannomas. GISTs are potentially malignant. Surgical treatment is recommended for localized GISTs of ≥20 mm. However, the indications for the diagnosis and follow-up of GISTs of <20 mm in size are controversial. There are several reports on the rapid progression or metastasis of small GISTs. Therefore, it is important to determine whether a SEL is a GIST or not. The main diagnostic method is EUS-FNA. Recently, endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) using a new biopsy needle has been reported to obtain larger tissue samples. Additionally, various biopsy methods have been reported to have a high diagnostic rate for small GISTs. In local gastric SELs, regardless of the tumor size, EUS can be performed first; then, EUS-FNA/B or various biopsy methods can be used to obtain tissue samples for decision-making in relation to therapy and the follow-up period.

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.

Recurrence of gastric gastrointestinal stromal tumor 12 years after repeat hepatectomies for liver metastases: report of a case

No consensus has been reached on the postoperative treatment and follow-up duration for high-risk malignant gastrointestinal stromal tumor (GIST). We herein report a case of recurrent liver metastasis from gastric GIST in a patient who had been receiving adjuvant chemotherapy with imatinib mesylate for 10 years. A 78-year-old woman underwent local gastrectomy for a 20-cm gastric GIST with a mitotic index of 25/50 high-power fields (HPF) 17 years before. Partial hepatectomy for recurrent liver metastases was repeatedly performed 14 and 12 years before. After the second hepatectomy, postoperative adjuvant chemotherapy with imatinib mesylate was given for 10 years, during which no recurrence was observed. Two years after the completion of adjuvant chemotherapy, computed tomography revealed a 2-cm hepatic tumor; thus, laparoscopic partial hepatectomy was performed. Histopathological findings revealed a liver metastasis of gastric GIST with a mitotic count of 20/50 HPF and MIB-1 labeling index of 20%. Mutation analysis of the KIT gene revealed an exon 11 mutation. The patient is currently undergoing postoperative adjuvant chemotherapy with imatinib mesylate. The combination of surgery and long-term adjuvant chemotherapy for high-risk malignant GIST and liver metastases may be effective to achieve a good prognosis.

Robot-assisted thoracoscopic esophagectomy for gastrointestinal stromal tumor of the esophagus: A case report

Introduction

A gastrointestinal stromal tumor (GIST) often arises in the stomach and small intestine, while esophageal GIST is rare. The first-choice treatment is surgical resection, but there is no standard technique. Herein, we describe our experience in the treatment of esophageal GIST and discuss the usefulness of robotic esophagectomy.

Presentation of case

The patient was a 60-year-old woman, who was diagnosed with a 30 mm GIST in the middle thoracic esophagus. We underwent robot-assisted thoracoscopic esophagectomy in the prone position. The duration of the thoracoscopic part was 69 min and the total operation time was 319 min. Total blood loss was 135 ml. The patient's postoperative course was uneventful after surgery and the patient was discharged home in good condition on the 18th postoperative day.

Discussion

The prognosis of esophageal GIST was less favorable compared with gastric GIST, and due to the anatomical peculiarities of the esophagus, which surgical procedure should be performed is still under debate. Robotic surgery has several technological advantages as it provides a three-dimensional view, ten times magnification, tremor control, and ambidexterity. Therefore, Robotic-assisted minimally invasive esophagectomy (RAMIE) allows achieving for safe R0 resection of esophageal GIST.

Conclusion

RAMIE may be useful for esophageal GIST because it facilitates safe and minimally invasive surgery in a limited space of the thoracic cavity.

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There is no standard technique due to the anatomical peculiarities of the esophagus.

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We think McKeown's procedure in the prone position has some advantages from others.

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Robot surgery has a three-dimensional view, tremor control, and ambidexterity.

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RAMIE would be useful techniques in a limited space of the thoracic cavity.

A Case of Liver Metastasis from Small Intestinal Gastrointestinal Stromal Tumor 25 Years after Surgery including Autopsy Findings

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor in the digestive tract. Recurrences may occur even after radical resection; however, recurrence later than 10 years after surgery is rare. We report a case of GIST with recurrence of liver metastasis 25 years after surgery. A 56-year-old man complained of sudden epigastric pain and was transferred to the emergency department. He had undergone partial resection of the small intestine for leiomyosarcoma 25 years previously. Abdominal computed tomography showed multiple liver tumors with massive hemorrhage. Ultrasound-guided percutaneous biopsy was performed for the 15-mm hepatic tumor in segment 2. Pathological findings revealed proliferation of spindle-shaped atypical cells, and immunostaining for c-kit and CD34 was both positive; the patient was therefore diagnosed with GIST. He then underwent chemotherapy for 7 years but died of multiple organ failure due to GIST. Autopsy revealed GIST occupying the entire liver with peritoneal dissemination, and minute lung metastases that could not be identified by CT were also detected. This case is interesting in considering the recurrence of GIST, and we will report it together with the literature review.

Gastrointestinal stromal tumors (GISTs) and synchronous intra-abdominal malignancies: case series of a single institution's experience

Background: Gastrointestinal stromal tumors (GISTs) quite often co-exist with other primary tumors, as seen in up to 33% of cases. In the literature such occurrences have primarily been described through case reports and rarely through case series, which is not sufficient to prove if there is an association between these two entities.

Materials and Methods: We conducted a retrospective study using medical and pathological records from sixty-nine patients who underwent surgical treatment for GIST in a single university surgical department between 2011 and 2019. Seven cases of GIST accompanying a synchronous primary tumor were identified and included in the study.

Results: Survival analysis comparing the overall survival of patients with single GIST versus patients with concurrent GIST and another primary tumor, has shown no statistically significant difference between these two groups (p = 0.19). However, when comparing the recurrence rate, patients with synchronous GISTs and another primary tumor have a statistically significant increased possibility for recurrence (p = 0.02). Statistical analysis comparing the size of GISTs between the two groups has shown that patients with single GIST have larger tumors than patients with synchronous tumors (p = 0.048).

Conclusions: The synchronous occurrence of GISTs and other intra-abdominal tumors is more common than previously considered, though it is not yet clear if there is a causal association for the concomitant occurrence. Further studies are required to elucidate the genetic and molecular mechanisms of carcinogenesis and progression associating GIST and synchronous tumors.

Metastatic gastrointestinal stromal tumor: A regional cancer center experience of 44 cases

BACKGROUND

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. Historically, a poor prognosis for metastatic disease has been reported with systemic chemotherapy. Significant advances have been made in the last decade, since the introduction of different tyrosine kinase inhibitors (TKIs). Unfortunately, even though the TKIs have been used for a long time, there are very few published data of the experience of TKI therapy in metastatic GIST from India.

MATERIALS AND METHODS

Patients diagnosed with metastatic GIST from January 2005 to October 2016 at our center, who received first-line therapy with imatinib 400 mg/day, were reviewed retrospectively. Patients' profile, response to treatment, toxicity of TKI therapy, time to progression, and survival were evaluated.

RESULTS

Of the 44 metastatic GIST patients, 23 (52.2%) were males. Median age at diagnosis was 48 years. The most common presenting symptom was an abdominal pain (52%), followed by weight loss (23%). Most frequently affected metastatic site was liver (57%), followed by peritoneum (16%), and lungs (4.5%). Metastases to both liver and peritoneum were found in 10 patients (22.5%). All patients were initially treated with imatinib at a dose of 400 mg/day. Disease stabilization was documented in 21 cases (48%), and 13 patients (29%) achieved a partial response. TKI therapy was well-tolerated in most cases. Median progression-free survival (PFS) was 26 months, and estimated median survival was 48 months. Patients with lung metastases have a significantly inferior median PFS and overall survival, in comparison to patients with other metastatic sites (P < 0.05).

CONCLUSIONS

Imatinib therapy was well tolerated and induced a sustained clinical benefit in more than half of the patients with metastatic GIST. Lung metastases seemed to be a poor prognostic factor in this patient population.

Retrospective Comparison of Endoscopic Full-Thickness Versus Laparoscopic or Surgical Resection of Small (≤ 5 cm) Gastric Gastrointestinal Stromal Tumors

AIM AND BACKGROUND

The aim of this study was to compare the efficacy and safety between endoscopic full-thickness resection (EFR) and laparoscopic or surgical resection methods for gastric gastrointestinal stromal tumor (GIST) in size of 5.0 cm or less. Gastric GISTs are common, and resection is the most effective treatment.

METHOD

We retrospectively reviewed 216 resections of gastric GISTs in size of up to 5.0 cm at our center from 2009 to 2017.Eligible resection cases were divided into EFR (n = 85), laparoscopic(n = 64), and surgical (n = 67) groups. The clinical records, patient demographic, symptoms, perioperative data, pathological findings, and long-term follow-up outcomes were collected and compared statistically.

RESULTS

No tumor rupture or recurrence occurred in the three groups. The prevalence of complications was significantly lower in EFR (5.9%) than both laparoscopic (7.8%) and surgical group (16.4%) (P < 0.01). In EFR group, the R0 resection rate (95.3%) was significantly lower than in the laparoscopic group and surgical group (100%) (P < 0.001). The hospital cost (OR = 62.79, CI: 12.954-304.363, P < 0.0001) were significantly lower in the EFR than in the laparoscopic group. The hospital cost (OR = 39.032, CI: 8.045-189.371, P < 0.0001) and post-operative diet time (OR = 2.779, CI: 1.225-6.304, P < 0.05) were also significantly lower in the EFR than in the surgical group.

CONCLUSION

EFR was a feasible treatment for gastric GISTs of size of ≤ 5.0 cm with an acceptable complete resection rate. In addition, EFR had significantly fewer postoperative complications, shorter length of hospital stay, and lower cost.

Application of A Convolutional Neural Network in The Diagnosis of Gastric Mesenchymal Tumors on Endoscopic Ultrasonography Images

Background and Aims: Endoscopic ultrasonography (EUS) is a useful diagnostic modality for evaluating gastric mesenchymal tumors; however, differentiating gastrointestinal stromal tumors (GISTs) from benign mesenchymal tumors such as leiomyomas and schwannomas remains challenging. For this reason, we developed a convolutional neural network computer-aided diagnosis (CNN-CAD) system that can analyze gastric mesenchymal tumors on EUS images. Methods: A total of 905 EUS images of gastric mesenchymal tumors (pathologically confirmed GIST, leiomyoma, and schwannoma) were used as a training dataset. Validation was performed using 212 EUS images of gastric mesenchymal tumors. This test dataset was interpreted by three experienced and three junior endoscopists. Results: The sensitivity, specificity, and accuracy of the CNN-CAD system for differentiating GISTs from non-GIST tumors were 83.0%, 75.5%, and 79.2%, respectively. Its diagnostic specificity and accuracy were significantly higher than those of two experienced and one junior endoscopists. In the further sequential analysis to differentiate leiomyoma from schwannoma in non-GIST tumors, the final diagnostic accuracy of the CNN-CAD system was 75.5%, which was significantly higher than that of two experienced and one junior endoscopists. Conclusions: Our CNN-CAD system showed high accuracy in diagnosing gastric mesenchymal tumors on EUS images. It may complement the current clinical practices in the EUS diagnosis of gastric mesenchymal tumors.

The Two Challenges in Management of Gastric Glomus Tumors

Gastric glomus tumors (GGTs) are rare gastrointestinal lesions originating from the neuromuscular arterial canal or vascular lumen which share many overlapping features with other stromal lesions. Despite most cases of GGTs being benign, there is a lack of reliable histological features predictive of tumor behavior. We present a case of a 42-year-old male who was determined to have a GGT via histological diagnosis and underwent surgical wedge resection. This case highlights the importance of establishing an accurate diagnosis and the various factors that must be taken into consideration to best determine malignant potential and management options.

Diagnosing Gastric Mesenchymal Tumors by Digital Endoscopic Ultrasonography Image Analysis

Gastric mesenchymal tumors (GMTs) are incidentally discovered in national gastric screening programs in Korea. Endoscopic ultrasonography (EUS) is the most useful diagnostic modality for evaluating GMTs. The differentiation of gastrointestinal stromal tumors from benign mesenchymal tumors, such as schwannomas or leiomyomas, is important to ensure appropriate clinical management. However, this is difficult and operator dependent because of the subjective interpretation of EUS images. Digital image analysis computes the distribution and spatial variation of pixels using texture analysis to extract useful data, enabling the objective analysis of EUS images and decreasing interobserver and intraobserver agreement in EUS image interpretation. This review aimed to summarize the usefulness and future of digital EUS image analysis for GMTs based on published reports and our experience.

Laparoscopic versus Open Resection for Gastric Gastrointestinal Stromal Tumors: A Meta-analysis

We conducted our meta-analysis to compare outcomes between laparoscopic resection and open resection for gastric gastrointestinal stromal tumors (GISTs) from all published comparative studies in the literature. Databases, including PubMed, Embase, Cochrane Library, Ovid, Web of Science, and CNKI, were searched to identify studies comparing outcomes after laparoscopic resection and open resection for gastric GISTs. The meta-analysis was performed by RevMan 5.1. Eleven comparative studies comprising 495 patients were identified. Patients undergoing laparoscopic resection of gastric GISTs were found to have similar operative time (weighted mean difference [WMD], 2.29; 95% confidence interval [CI], -16.01 to 11.43; P = 0.74) and complications rate (odds ratio [OR], 0.76; 95% CI, 0.36 to 1.58; P = 0.46). Less intraoperative blood loss (WMD, -55.91; 95% CI, -90.26 to -21.56; P = 0.001), earlier passing first flatus (WMD, -0.89, 95% CI, -1.60 to -0.18; P = 0.01), earlier having the first liquid diet (WMD, -1.54; 95% CI, -2.44 to -0.64; P = 0.0008), and shorter hospital stay (WMD, -4.25; 95% CI, -5.63 to -2.88; P < 0.00001) were observed in the laparoscopic resection group. The recurrence rate was higher in the group of open resection compared with the group of laparoscopic resection (OR, 0.26; 95% CI, 0.09 to 0.75; P = 0.01). Laparoscopic resection is safe and efficient in the treatment of patients with gastric GISTs as compared with open resection procedure. Laparoscopic resection may be a preferred treatment for gastric GISTs.

Retrospective Analysis of Chilean and Mexican GI Stromal Tumor Registries: A Tale of Two Latin American Realities

PURPOSE

Like other malignancies, GI stromal tumors (GIST) are highly heterogeneous. This not only applies to histologic features and malignant potential, but also to geographic incidence rates. Several studies have reported GIST incidence and prevalence in Europe and North America. In contrast, GIST incidence rates in South America are largely unknown, and only a few studies have reported GIST prevalence in Latin America.

PATIENTS AND METHODS

Our study was part of a collaborative effort between Chile and Mexico, called Salud con Datos. We sought to determine GIST prevalence and patients' clinical characteristics, including survival rates, through retrospective analysis.

RESULTS

Overall, 624 patients were included in our study. Our results found significant differences between Mexican and Chilean registries, such as stage at diagnosis, primary tumor location, CD117-positive immunohistochemistry status, mitotic index, and tumor size. Overall survival (OS) times for Chilean and Mexican patients with GIST were 134 and 156 months, respectively. No statistically significant differences in OS were detected by sex, age, stage at diagnosis, or recurrence status in both cohorts. As expected, patients categorized as being at high risk of recurrence displayed a trend toward poorer progression-free survival in both registries.

CONCLUSION

To the best of our knowledge, this is the largest report from Latin America assessing the prevalence, clinical characteristics, postsurgery risk of recurrence, and outcomes of patients with GIST. Our data confirm surgery as the standard treatment of localized disease and confirm a poorer prognosis in patients with regional or distant disease. Finally, observed differences between registries could be a result of registration bias.

Pelvic Gastrointestinal Stromal Tumor With Pulmonary Metastasis

Extragastrointestinal stromal tumors (EGISTs) comprise a small portion of gastrointestinal stromal tumors. Metastasis normally occurs to nearby organs. However, metastasis to the lungs is uncommon in EGISTs. Furthermore, recurrence of the EGIST in a new location years later has not been documented. We present this case to highlight this behavior of EGISTs in hopes to better understand this rare type of neoplasm.

Duodenojejunal intussusception secondary to primary gastrointestinal stromal tumor: A case report

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Gastrointestinal stromal tumor (GIST) in the third portion of the duodenum is rare.

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Intussusception and obstruction caused by GIST are uncommon.

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Adult intussusception usually requires surgical resection.

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If the location, tumor size, and resection margin of duodenal GIST are adequate for limited resection, it seems to be better than pancreaticoduodenectomy.

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Elderly patients can have improved quality of life with minimally invasive surgery.

Introduction

Gastrointestinal stromal tumors (GISTs) in the third portion of the duodenum are rare. Intussusception and obstruction are rarely caused by GISTs because of their tendency to grow in an extraluminal manner. Herein, we report a case involving segmental duodenectomy in a patient with duodenojejunal intussusception secondary to a primary GIST.

Presentation of case

A 91-year-old woman with a history of iron-deficiency anemia presented with vomiting and anorexia. Preoperative imaging suggested duodenojejunal intussusception secondary to a GIST in the third portion of the duodenum. Segmental duodenectomy with end-to-end duodenojejunostomy without reduction of the intussusception was performed. At 6 months after the surgery, the patient’s anemia had improved and she had no abdominal symptoms.

Discussion

Adult intussusception requires surgical resection because most of the patients have intraluminal lesions. The location in relation to the Vater papilla, tumor size, and resection margin should be considered when selecting the type of surgical resection for duodenal GIST. Limited resection appears to be better than pancreaticoduodenectomy with respect to postoperative complications. Considering the age and performance status of this patient, a less invasive maneuver was selected.

Conclusion

Duodenal GISTs can be a rare cause of intussusception. Thus, a limited surgical resection procedure should be considered in such cases.

[Multiple gastrointestinal stromal masses in the small bowel detected in a patient with peritonitis]

Nous rapportons une observation d'un cas de tumeur stromale gastro-intestinale à localisation multiple au niveau du grêle découverte dans un contexte de péritonite. La particularité de ce cas tient à la découverte en per-opératoire de masses tumorales multifocales grêliques, évoquant à la tomodensitométrie en post opératoire des tumeurs stromales gastro-intestinales. Ce tableau clinique de péritonite ne permettait en aucun cas d'évoquer une origine tumorale.

Digital image analysis-based scoring system for endoscopic ultrasonography is useful in predicting gastrointestinal stromal tumors

BACKGROUND

When gastric mesenchymal tumors (GMTs) measuring 2-5 cm in size are found, whether to undergo further treatment or not is controversial. Endoscopic ultrasonography (EUS) is useful for the evaluation of malignant potential of GMTs, but has limitations, such as subjective interpretation of EUS images. Therefore, we aimed to develop a scoring system based on the digital image analysis of EUS images to predict gastrointestinal stromal tumors (GISTs).

METHODS

We included 103 patients with histopathologically proven GIST, leiomyoma or schwannoma on surgically resected specimen who underwent EUS examination between January 2007 and June 2018. After standardization of the EUS images, brightness values, including the mean (T_mean), indicative of echogenicity, and the standard deviation (T_SD), indicative of heterogeneity, in the tumors were analyzed.

RESULTS

Age, T_mean, and T_SD were significantly higher in GISTs than in non-GISTs. The sensitivity and specificity were almost optimized for differentiating GISTs from non-GISTs when the critical values of age, T_mean, and T_SD were 57.5 years, 67.0, and 25.6, respectively. A GIST-predicting scoring system was created by assigning 3 points for T_mean ≥ 67, 2 points for age ≥ 58 years, and 1 point for T_SD ≥ 26. When GMTs with 3 points or more were diagnosed as GISTs, the sensitivity, specificity, and accuracy of the scoring system were 86.5%, 75.9%, and 83.5%, respectively.

CONCLUSIONS

The scoring system based on the information of digital image analysis is useful in predicting GISTs in case of GMTs that are 2-5 cm in size.

Malignant Extra-Gastrointestinal Stromal Tumor of the Mesentery

Gastrointestinal stromal tumors (GISTs), the commonest mesenchymal tumors of gastrointestinal tract are often described to take origin from the interstitial cells of Cajal (ICC) or its precursor cells. Rarely these tumors do arise in structures other than the alimentary tract like omentum, mesentery, retroperitoneum, etc., of varying malignant potential and are known as extra-gastrointestinal stromal tumors (eGISTs).

This is a case report of a 70-year-old female with multicentric malignant eGISTs arising in the mesentery of ileum. On laparotomy, a large mass of 20 × 15 cm was found in the small bowel mesentery without involvement of the adjacent ileum, with multiple other small nodules resembling lymph nodes, present adjacent to it. Histopathological study of the excised lump, confirmed the mass to be malignant eGIST without involvement of the adjacent ileum, with cluster differentiation (CD)117 positive and of high-risk stratification. The mesenteric nodule was confirmed on histopathology to be malignant eGIST, similar to that of that of the primary, without any lymphoid tissue. Adjuvant imatinib mesylate treatment was started immediately postoperation with the patient doing well at 1 year of follow-up. We report this case, due to the rare occurrence of multifocal malignant eGISTS of small bowel mesentery, which is yet to be reported. The existing literature is unclear regarding the clinicopathology and management of multifocal malignant stromal tumors of the mesentery.

Endoscopic features of gastrointestinal stromal tumor in the small intestine

Background/Aims

Gastrointestinal stromal tumor (GIST) is one of the most common types of submucosal tumors (SMTs). Because of GIST’s malignant potential, it is crucial to differentiate it from other SMTs. The present study aimed to identify characteristic endoscopic findings of GISTs in the small intestine.

Methods

We reviewed the clinicopathological and endoscopic findings of 38 patients with endoscopically or surgically resected SMTs in the small intestine. SMTs were classified into GIST and non-GIST groups, and clinicopathological and endoscopic findings were compared between the 2 groups.

Results

Fifteen patients had GIST and 23 patients had other types of SMTs in the small intestine. Comparison of the endoscopic findings between the 2 groups revealed that dilated vessels in the surrounding mucosa were significantly more in number in the GIST group than in the non-GIST group (P<0.05). However, there were no other differences in endoscopic findings between the 2 groups. Among patients with GISTs, the presence of dilated vessels in the surrounding mucosa was not associated with bleeding risk, tumor size, or metastasis rate at diagnosis.

Conclusions

Dilated vessels in the surrounding mucosa, identified during balloon-assisted endoscopy, may be a diagnostic indicator for GIST in the small intestine. However, its clinical significance should be further analyzed.

New frontiers in the medical management of gastrointestinal stromal tumours

The tyrosine kinase inhibitor (TKI) imatinib has radically changed the natural history of KIT-driven gastrointestinal stromal tumours (GISTs). Approved second-line and third-line medical therapies are represented by the TKIs sunitinib and regorafenib, respectively. While imatinib remains the cardinal drug for patients with GISTs, novel therapies are being developed and clinically tested to overcome the mechanisms of resistance after treatments with the approved TKI, or to treat subsets of GISTs driven by rarer molecular events. Here, we review the therapy of GISTs, with a particular focus on the newest drugs in advanced phases of clinical testing that might soon change the current therapeutic algorithm.

Nonovarian Mimics of Ovarian Malignancy

Once a pelvic mass is identified on an ultrasound examination, the first step in the differential diagnostic work up is to determine its origin. Most lateral pelvic masses in women are ovarian in origin, and the distinction between ovarian and nonovarian mimics of ovarian cancer is critical for appropriate clinical and surgical management. Adnexal masses detected on ultrasound can be further characterized by magnetic resonance imaging (MRI) when needed. Superior contrast resolution, multiplanar imaging, characteristic signal intensity of common pathology such as dermoid tumors or endometriomas allows one to accurately evaluate adnexal tumors with supplemental use of MRI. Commonly encountered extraovarian abnormalities that mimic ovarian malignancies are categorized as being either predominantly cystic or solid. The common causes of such extraovarian lesions that mimic ovarian pathology include fallopian tube diseases, paroaovarian cysts, peritoneal inclusion cysts, and a pedunculated or a broad ligament fibroid. Less common causes of cystic and solid nonovarian mimics of ovarian malignancy include mucocele of the appendix, lymphocele, spinal meningeal cysts, extraovarian endometriomas, extraovarian fibrothecomas, and gastrointestinal stromal tumors (Table 1). Identifying a normal appearing ovary is the key in distinguishing an extraovarian pelvic mass from an ovarian tumor. This becomes particularly challenging in postmenopausal women with atrophic ovaries. In this scenario, MRI comes into use by identifying small atrophic ovaries more often than ultrasound is able to. Extraovarian lesions typically displace the pelvic sidewall vasculature medially, ureters tend to be compressed, encased or medially displaced, enhancement matches pelvic arteries and may be associated with engorged mesenteric vessels compared to gonadal vessel engorgement seen with ovarian tumors.

A new nomogram for recurrence-free survival prediction of gastrointestinal stromal tumors: Comparison with current risk classification methods

BACKGROUND

This study aimed to build a new risk stratification nomogram for gastrointestinal stromal tumors (GISTs) focused on a popular factor Ki-67 to enable individualized and precise predictions of the most suitable candidates for imatinib therapy.

METHODS

We retrospectively collected clinicopathologic data of the patients diagnosed with GISTs from January 1998 to December 2015 at Southern Medical University Nanfang Hospital as the experiment group. And patients with GISTs at the Sun Yat-sen University Cancer Center from January 2007 to December 2012 were included as the validation group. The nomogram was built using Kaplan-Meier method and the Cox proportional hazards regression model. The receiver operating characteristic (ROC) curves were established to compare the discriminative ability of the new nomogram with other risk stratification systems, including the modified National Institute of Health (modified NIH) criteria, Armed Forces Institute of Pathology (AFIP) criteria, Memorial Sloan Kettering Cancer Center (MSKCC) prognostic nomogram, and contour maps.

RESULTS

In univariate analysis, the tumor size, site, mitotic count, tumor rupture and Ki-67 labeling index were significant factors (all P < 0.05) and included in the Cox model to build our nomogram. According to the ROC curve, our new nomogram showed the largest AUC value (0.778) compared with that of the other classification methods (contour maps, AUC = 0.743; AFIP, AUC = 0.719; MSKCC, AUC = 0.712; and modified NIH, AUC = 0.719).

CONCLUSION

Our new nomogram exhibits an excellent performance and might become a potential risk stratification to support therapeutic decision-making for GISTs.

Minimally Invasive Intragastric Approach to Gastroesophageal Junction Disease

BACKGROUND

A minimally invasive intragastric approach to the gastroesophageal junction (GEJ) allows resection of intramural disease while avoiding disruption of the lower esophageal sphincter and vagus nerves. Few surgeons use this approach; thus little is known regarding its indications, feasibility, technical aspects, complication profile, and long-term outcomes. This study reviewed the experience with this technique.

METHODS

A retrospective review was performed of a prospectively maintained, Institutional Review Board-approved database covering the period from January 1, 2005 to August 1, 2017. Indications, operative details, postoperative complications, and outcomes were assessed.

RESULTS

There were 12 patients identified. The mean age of these patients was 51.9 years. The indications for resection included 10 symptomatic leiomyomas, one gastrointestinal stromal tumor, and three cancers of the GEJ. Mean and median length of stay were 4.9 and 2.5 days, respectively. There were two postoperative esophageal leaks managed with laparoscopic repair. Of the 3 patients with cancer, 2 underwent an R0 resection, whereas 1 patient underwent an R1 resection. There were no other complications or recurrences. Mean follow-up was 6.0 years (range, 0.5 to 12.6 years); no patients had stricture or symptomatic gastroesophageal reflux on long term follow-up.

CONCLUSIONS

Resection of selected intramural GEJ disorders through a minimally invasive transgastric approach can be performed safely with acceptable morbidity and good long-term results. The approach allows preservation of the lower esophageal sphincter and vagus nerves, a potential advantage compared with other surgical alternatives to resection in this region.

Gastrointestinal stromal tumors: A clinical and histopathological presentation of 27 cases

OBJECTIVE

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that express type 3 tyrosine kinase receptors and are thought to develop from the neoplastic transformation of the interstitial Cajal cells. The present study was performed to morphologically and immunohistologically evaluate GISTs, to compare their qualities using a GIST risk categorization system, and to identify the diagnostic and prognostic parameters of GISTs.

MATERIAL AND METHODS

A total of 27 patients with GISTs underwent treatment and were followed up at the Gaziosmanpaşa Taksim Training and Research Hospital. Descriptive statistics was used to calculate the mean and median values. Survival analysis was performed by the Kaplan-Meier method. The analyses were performed using the SPSS version 22.0 software.

RESULTS

The mean follow-up time was 3.5 (5 months to 13 years) years. The mean age was 60.4 (29-82) years. The tumors were localized in the stomach (62.9%), extraintestinal areas (14.8%), intestine (7.4%), esophagus (7.4%), and rectum (7.4%). Twenty-four patients were classified according to the Fletcher system. Of these patients, 7 (25.9%) were classified as very low risk, 8 (29.6%) as low risk, 7 (25.9%) as intermediate risk, and 2 (7.4%) as high risk. Twenty-four patients underwent surgery. Of the 3 patients who did not undergo surgery, 1 had metastatic disease at the time of diagnosis, and 2 had mini- or micro-GISTs in the stomach. On endoscopic surveillance, all tumors remained stable. Three out of the 27 patients were lost to follow-up. Two patients developed recurrence, and 1 patient died of GIST.

CONCLUSION

We analyzed the clinical and pathological characteristics of GIST. The most common site of tumor origin was the stomach. The size, mitotic index, and Ki-67 values were to be found high in intermediate- and high-risk groups and metastatic diseases.

Laparoscopic Surgery for Large Gastric Submucosal Tumors

BACKGROUND

In general, laparoscopic resection for gastric gastrointestinal stromal tumors (GISTs) >5 cm is not recommended. However, there is a lack of evidence to support this recommendation.

PATIENTS AND METHODS

This study included 108 patients who underwent laparoscopic surgery for gastric GISTs. Of the 108 patients, 23 had GISTs>5 cm. The aim of this study is to evaluate the oncological safety of laparoscopic surgery for large gastric GISTs. In addition, we performed a rapid systematic review of laparoscopic surgery for large gastric GISTs.

RESULTS

In our cases, all patients were performed R0 resection without capsular rupture and surgical margins were negative on pathologic examination. In all studies, en bloc resection was achieved without capsular rupture in all patients. The average positive surgical margins rate was 1.6% in total reports.

CONCLUSIONS

The laparoscopic approach for large gastric GISTs>5 cm has been proposed as safe when performed by experienced surgeons.

Submucosal tunnel endoscopic resection for extraluminal tumors: a novel endoscopic method for en bloc resection of predominant extraluminal growing subepithelial tumors or extra-gastrointestinal tumors (with videos)

BACKGROUND AND AIMS

The management of subepithelial tumors with a predominant extraluminal growth pattern or extra-GI tumors can be challenging and traditionally requires a surgical resection that is not only invasive but may carry a significant risk of morbidity and mortality. We aimed to assess the feasibility, safety, and efficacy of a novel endoscopic technique termed submucosal tunnel endoscopic resection for extraluminal tumors (STER-ET).

METHODS

We prospectively enrolled patients who underwent STER-ET for GI subepithelial tumors with a predominant extraluminal growth pattern or extra-GI tumors located at the level of cardia or the proximal part of the lesser curvature of the stomach seen on cross-sectional imaging between January 2016 and March 2017.

RESULTS

Eight patients underwent STER-ET. The mean (± standard deviation) tumor size was 2.8 ± 0.6 cm and 2.3 ± 0.8 cm in longest and shortest dimension, respectively. The average procedure time was 67 ± 4.4 minutes. The rates of curative en bloc resection and en bloc retrieval was 100% and 87.5%, respectively. On final histology, 6 tumors were GI stromal tumors, 1 was a schwannoma, and 1 was a foregut cyst. Five patients had capnoperitoneum during the procedure and required abdominal decompression. One patient had a small mucosotomy successfully treated with a hemostatic clip. There were no major adverse events or deaths. The median length of hospital stay was 3 days. There was no residual tumor on surveillance imaging after a mean follow-up period of 10.0 ± 2.1 months.

CONCLUSIONS

STER-ET is a novel technique that appears to be safe and effective in achieving a curative resection for GI subepithelial tumors with a predominantly extraluminal growth pattern or extraluminal tumors in a selected group of patients. However, larger studies are required to validate our finding.

Surgical Management of Gastric Gastrointestinal Stromal Tumours: Comparison of Outcomes for Local and Radical Resection

Gastrointestinal stromal tumours (GISTs) most commonly originate from the stomach. Their treatment is dependent on size and whether they are symptomatic. Curative treatment requires surgery, which may be preceded by neoadjuvant imatinib if it is felt that this will aid in achieving clear (R0) resection margins. The aim of this study was to evaluate outcomes from patients that underwent a "local" organ-preserving operation, with those that required a more radical resection, and the influences on selecting a more radical resection. A retrospective review of patients undergoing surgery for symptomatic gastric GISTs from a single institution over 9 years was carried out. Patients were divided into three cohorts dependent on whether they had a "local" resection, "anatomical" resection, or "extended" resection. 71 patients were included. Overall, 5-year survival was 92%. Operating time, blood loss, and length of stay were significantly lower in the group undergoing local resection (p < 0.05). Tumour size was also smaller in the local group (median 4 cm versus 5 cm p < 0.05). Tumour location also influenced the type of surgery performed, with tumours at the cardia, gastroesophageal junction, and antrum all having "anatomical" resections. Lymphadenectomy did not appear to impact on outcomes. These findings indicate that local excision, where possible, does not impair oncological outcomes.

Gastrointestinal stromal tumours: advances in surgical and pharmacological management options

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract. The stomach is most commonly affected. Advances in immunopathology have identified a mutation in the c-KIT proto-oncogene, leading to the development of the tyrosine-kinase inhibitor Imatinib as targeted therapy for advanced disease. Surgery, however, remains the only curative treatment of resectable primary GIST. This review article aims at reviewing the management of primary GISTs, investigating recurrences, exploring the role of surgery in metastatic disease and looking into combined surgery and molecular therapy for GISTs.

Clinicopathological features, surgical strategy and prognosis of duodenal gastrointestinal stromal tumors: a series of 300 patients

BACKGROUND

The relatively low incidence of duodenal gastrointestinal stromal tumors (GISTs) and the unique anatomy make the surgical management and outcomes of this kind of tumor still under debate. Thus, this study aimed to explore the optimal surgical strategy and prognosis of duodenal GISTs.

METHODS

A total of 300 cases of duodenal GISTs were obtained from our center (37 cases) and from case reports or series (263 cases) extracted from MEDLINE. Clinicopathological features, type of resections and survivals of duodenal GISTs were analyzed.

RESULTS

The most common location of duodenal GISTs was descending portion (137/266, 51.5%). The median tumor size was 4 cm (0.1-28). Most patients (66.3%) received limited resection (LR). Pancreaticoduodenectomy (PD) was mainly performed for GISTs with larger tumor size or arose from descending portion (both P < 0.05). For both the entire cohort and tumors located in the descending portion, PD was not an independent risk factor for disease-free survival (DFS) and disease-specific survival (DSS) (both P > 0.05). Duodenal GISTs were significantly different from gastric GISTs with respect to tumor size, mitotic index and NIH risk category (all P < 0.05). The DFS and DSS of duodenal GISTs was significantly worse than that of gastric GISTs (both P < 0.05).

CONCLUSIONS

LR was a more prevalent surgical procedure and PD was mainly performed for tumors with larger diameter or located in descending portion. Type of resection was not an independent risk factor for the prognosis of duodenal GISTs. Prognosis of duodenal GISTs was significantly worse than that of gastric GISTs.

Clinical Presentation and Treatment of Gastrointestinal Stromal Tumors

Aims and background

Gastrointestinal stromal tumors (GISTs), although rare, are the most common mesenchymal neoplasms affecting the gastrointestinal tract. We present our experience in the treatment of localized and metastatic disease and a review of literature.

Patients and methods

Nine patients were observed from April 2002 to July 2004. Eight tumors were in the gastric area and J was in the small bowel. In 5 cases, complete surgical removal was performed, and none of these patients underwent adjuvant therapy. The remaining 4 cases, with locally advanced or recurrent disease, were treated with imatinib.

Results

The patients with localized disease treated only by surgery did not relapse. In the patients with locally advanced or metastatic disease treated by imatinib, we observed 3 partial responses, and one case was not assessable because he had no measurable disease. In 2 of 3 responders, it was possible to perform a new radical surgery.

Conclusions

Our series is too small to draw any conclusion. According to our review of the literature, surgery remains the standard treatment for non-metastatic GISTs. Imatinib mesylate represents a major breakthrough in the treatment of advanced GISTs and is the first effective systemic therapy for the disease.

Challenging Diagnosis of Ileal Gastrointestinal Stromal Tumor Presenting with Obscure Digestive Bleeding

We report a case of a patient observed in emergency condition for recurrent episodes of massive obscure gastrointestinal bleeding that required surgical control. At laparotomy we found an ileal mass with the characteristics of a gastrointestinal stromal tumor (GIST) at histopathological analysis. GISTs should always be considered as a possible cause of obscure gastrointestinal bleeding, although they are often difficult to diagnose preoperatively. Laparotomy is sometimes the only way to obtain a diagnosis. Starting from this case, we reviewed the literature about GISTs, focusing our attention on their diagnosis and the possible surgical and nonsurgical therapies.

Molecularly Targeted Therapy and Radiotherapy in the Management of Localized Gastrointestinal Stromal Tumor (GIST) of the Rectum: A Case Report

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. The main treatment for localized gastrointestinal stromal tumors is surgical resection. These tumors respond poorly to conventional cytotoxic chemotherapy agents and to radiotherapy. Imatinib mesylate, a small-molecule kinase inhibitor, has proved useful in the treatment of recurrent or metastatic GISTs and is now being tested in the adjuvant and neoadjuvant setting. The role of radiotherapy in the management of patients with GIST is currently restricted to symptomatic palliation.

We present the case of a 54-year-old man affected by rectal GIST extending to the anal canal, with constipation, hematochezia, and anal pain. He received imatinib, 400 mg orally per day, for a week before and during radiation therapy. Irradiation was delivered to the gross tumor volume by 3D conformal therapy. The planned total dose was 50.4 Gy in fractions of 1.8 Gy daily. We observed a partial clinical response 3 weeks after the end of combination treatment. The patient then underwent a sphincter-saving surgical procedure. There was no perioperative morbidity and a complete pathological response was obtained.

At the present time, the role of radiotherapy in the management of patients with GIST is restricted to symptomatic palliation. The introduction of molecularly targeted therapy combined with radiation therapy could improve the outcomes for patients diagnosed with GIST.

Gastrointestinal Stromal Tumors (GISTs): From Science to Targeted Therapy

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. GISTs represent a distinct category of tumors characterized by oncogenic mutations of the KIT receptor tyrosine kinase in a majority of patients. KIT is useful not only for the diagnosis but also for targeted therapy of this disease. Imatinib, a tyrosine kinase inhibitor, is widely used in advanced and metastatic GISTs. This agent revolutionized the treatment strategy of advanced disease and is being tested in the neoadjuvant and adjuvant settings with encouraging results. New therapeutic agents like sunitinib have now been approved, enriching the treatment scenario for imatinib-resistant GISTs. The present review reports on the peculiar characteristics of this disease through its biology and molecular patterns, focusing on the predictive value of KIT mutations and their correlation with clinical outcome as well as on the activity of and resistance to approved targeted drugs.