Gastrointestinal stromal tumors in children and young adults: a clinicopathologic and molecular genetic study of 22 Korean cases

Research progress on the pathogenesis of the SDHB mutation and related diseases

With the improvement of genetic testing technology in diseases in recent years, researchers have a more detailed and clear understanding of the source of cancers. Succinate dehydrogenase B (SDHB), a mitochondrial gene, is related to the metabolic activities of cells and tissues throughout the body. The mutations of SDHB have been found in pheochromocytoma, paraganglioma and other cancers, and is proved to affect the occurrence and progress of those cancers due to the important structural functions. The importance of SDHB is attracting more and more attention of researchers, however, reviews on the structure and function of SDHB, as well as on the mechanism of its carcinogenesis is inadequate. This paper reviews the relationship between SDHB mutations and related cancers, discusses the molecular mechanism of SDHB mutations that may lead to tumor formation, analyzes the mutation spectrum, structural domains, and penetrance of SDHB and sorts out some of the previously discovered diseases. For the patients with SDHB mutation, it is recommended that people in SDHB mutation families undergo regular genetic testing or SDHB immunohistochemistry (IHC). The purpose of this paper is hopefully to provide some reference and help for follow-up researches on SDHB.

Treatment of Gastrointestinal Stromal Tumors (GISTs): A Focus on Younger Patients

Gastrointestinal stromal tumors (GISTs) originate from Cajal's cells and are the most common mesenchymal neoplasms of the gastrointestinal tract. GISTs in young adults, i.e., patients before the age of 40, are rare and differ from those in older patients and GISTs in children in terms of the molecular and clinical features, including the location and type of mutations. They often harbor other molecular abnormalities than KIT and PDGFRA mutations (wild-type GISTs). The general principles of therapeutic management in young patients are the same as in the elderly. Considering some differences in molecular abnormalities, molecular testing should be the standard procedure to allow appropriate systemic therapy if needed. The optimal treatment strategy should be established by a multidisciplinary team experienced in sarcoma treatment. The impact of treatment on the quality of life and daily activities, including the impact on work, pregnancy, and fertility, in this patient population should be especially taken into consideration.

Clinical features of multiple gastrointestinal stromal tumors: A pooling analysis combined with evidence and gap map

BACKGROUND

Multiple gastrointestinal stromal tumors (MGISTs) are a very rare type of gastrointestinal stromal tumor (GIST) and are usually observed in syndrome.

AIM

The paper aimed to describe the clinical and oncological features of MGISTs and to offer evidence for the diagnosis and treatment.

METHODS

Data of consecutive patients with MGISTs who were diagnosed at Peking University People’s Hospital (PKUPH) from 2008 to 2019 were retrospectively evaluated. Further, a literature search was conducted by retrieving data from PubMed, EMBASE, and the Cochrane library databases from inception up to November 30, 2019.

RESULTS

In all, 12 patients were diagnosed with MGISTs at PKUPH, and 43 published records were ultimately included following the literature review. Combined analysis of the whole individual patient data showed that female (59.30%), young (14.45%), and syndromic GIST (63.95%) patients comprised a large proportion of the total patient population. Tumors were mainly located in the small intestine (58.92%), and both CD117 and CD34 were generally positive. After a mean 78.32-mo follow-up, the estimated median overall survival duration (11.5 years) was similar to single GISTs, but recurrence-free survival was relatively poorer.

CONCLUSION

The clinical and oncological features are potentially different between MGISTs and single GIST. Further studies are needed to explore appropriate surgical approach and adjuvant therapy.

Gastrointestinal Stromal Tumours (GIST) in Young Adult (18-40 Years) Patients: A Report from the Dutch GIST Registry

Gastrointestinal stromal tumour (GIST) is a disease of older adults and is dominated by KIT/PDGFR mutations. In children, GIST is rare, predominantly occurs in girls, has a stomach location and generally lacks KIT/PDGFR mutations. For young adults (YA), aged 18 to 40 years, the typical phenotypic and genotypic patterns are unknown. We therefore aimed to describe the clinical, pathological and molecular characteristics of GIST in in YA. YA GIST patients registered in the Dutch GIST Registry (DGR) were included, and data were compared to those of older adults (OA). From 1010 patients in the DGR, 52 patients were YA (54% male). Main tumour locations were stomach (46%) and small intestine (46%). GIST genetic profiles were mutations in KIT (69%), PDGFRA (6%), SDH deficient (8%), NF1 associated (4%), ETV6-NTRK3 gene fusion (2%) or wildtype (10%). Statistically significant differences were found between the OA and YA patients (localisation, syndromic and mutational status). YA presented more often than OA in an emergency setting (18% vs. 9%). The overall five-year survival rate was 85%. In conclusion, YA GISTs are not similar to typical adult GISTs and also differ from paediatric GISTs, as described in the literature. In this series, we found a relatively high percentage of small intestine GIST, emergency presentation, 25% non-KIT/PDGFRA mutations and a relatively good survival.

Gene of the month: SDH

Succinate dehydrogenase (SDH) is a heterotetrameric nuclear encoded mitochondrial protein complex which plays a role in the citric acid cycle and the electron transfer chain. Germline mutations in SDHA are associated with Leigh syndrome. Mutations in SDHB, SDHC and SDHD are found in an increasing number of neoplasms, most notably paragangliomas and wild-type gastrointestinal stromal tumours. SDH deficiency in these tumours has important prognostic implications, and also provides a novel target for molecular therapy. In this article, we outline the structure and function of SDH and provide a summary of its role in various diseases.

Clinicopathologic features and prognosis of primary gastrointestinal stromal tumor patients under 35 years of age: A 10-year retrospective study

OBJECTIVES

To investigate gastrointestinal stromal tumor (GIST) clinicopathologic characteristics in young adults.

METHODS

Clinicopathologic data from GIST patients under 35 years diagnosed at our hospital from January 2005 to December 2014 were retrospectively collected.

RESULTS

Thirty-one (5.3%, 31/585) patients were included; 17 (54.8%) were female. The most common presentation and primary tumor site were gastrointestinal bleeding (n = 18, 58.1%) and the small intestine (n = 13, 41.9%), respectively. Fifteen (48.4%) GISTs were classified as having a high relapse risk; two (6.4%), intermediate; nine (29.0%), low; and five (16.1%), very low. All patients underwent tumor resection. With a median follow-up of 51 months for 20 (64.5%) patients, 12 (60%) were given imatinib methylate as adjuvant therapy. One (5%) patient died of peritoneal GIST dissemination, four (20%) developed abdominal recurrences, two (10%) had hepatic metastasis, and thirteen (65%) were disease free. The 5-year disease-free survival rate was 51.2%.

CONCLUSIONS

GISTs rarely occur in young adults. The most common location is the small intestine. A slight female predominance was observed in the current study. Adjuvant therapy longer than the recommended duration may be beneficial for GISTs with a high relapse risk. Combined targeted therapy and surgery is appropriate for recurrent and metastatic GISTs in select patients. J. Surg. Oncol. 2016;114:977-981. © 2016 Wiley Periodicals, Inc.

Rare Case of Primary Gastric Burkitt Lymphoma in a Child

Primary gastric tumors are very rare in children. Burkitt lymphoma is a common type of non-Hodgkin's lymphoma, and gastric Burkitt lymphoma usually occurs in the aged. When involving the gastrointestinal tract, primary gastric Burkitt lymphoma is very rare in younger childhood. Many gastric lymphomas including mucosa-associated lymphoid tissue lymphoma are associated with Helicobacter pylori infection or acute bleeding symptom. We report a seven-year-old boy who presented with only some vomiting and postprandial pain. His upper gastrointestinal endoscopy and biopsy revealed a large primary Burkitt lymphoma with no acute bleeding and no evidence of H. pylori infection. After chemotherapy, he remains in remission.

Prognosis and management of adult wild type gastrointestinal stromal tumours (GISTs): A pooled analysis and review of literature

A pooled review was performed to determine survival in adult WT GIST (Wild Type GastroIntestinal Stromal Tumours) and compare the same with pediatric WT GISTs. Electronic databases were searched using the terms "Wild type" AND "GIST". Eighty-two adult patients from 14 studies were included in the pooled analysis. Cumulative survival was greater than 50% in both age groups, hence medial survival could not be computed. Mean survival in adults was 15.7 years ± 0.78 and in children was 18.8 years ± 1.3 (p = 0.241). Median disease free survival in adults was 10 years while 5-year overall survival was 88%. There was no statistically significant difference in the survival between the two groups (p = 0.241). Overall survival in adults with WT GISTs is favourable compared to other adult GIST subtypes likely reflects a common molecular pathway similar to pediatric GIST.

Succinate dehydrogenase-deficient gastrointestinal stromal tumors

Most gastrointestinal stromal tumors (GISTs) are characterized by KIT or platelet-derived growth factor alpha (PDGFRA) activating mutations. However, there are still 10%-15% of GISTs lacking KIT and PDGFRA mutations, called wild-type GISTs (WT GISTs). Among these so-called WT GISTs, a small subset is associated with succinate dehydrogenase (SDH) deficiency, known as SDH-deficient GISTs. In addition, GISTs that occur in Carney triad and Carney-Stratakis syndrome represent specific examples of SDH-deficient GISTs. SDH-deficient GISTs locate exclusively in the stomach, showing predilection for children and young adults with female preponderance. The tumor generally pursues an indolent course and exhibits primary resistance to imatinib therapy in most cases. Loss of succinate dehydrogenase subunit B expression and overexpression of insulin-like growth factor 1 receptor (IGF1R) are common features of SDH-deficient GISTs. In WT GISTs without succinate dehydrogenase activity, upregulation of hypoxia-inducible factor 1α may lead to increased growth signaling through IGF1R and vascular endothelial growth factor receptor (VEGFR). As a result, IGF1R and VEGFR are promising to be the novel therapeutic targets of GISTs. This review will update the current knowledge on characteristics of SDH-deficient GISTs and further discuss the possible mechanisms of tumorigenesis and clinical management of SDH-deficient GISTs.

Laparoscopic resection of a rare gastrointestinal stromal tumor in children

Introduction

Gastrointestinal stromal tumors (GIST) are uncommon mesenchymal tumors of the gastrointestinal (GI) tract, accounting for 0.1% to 3% of all GI malignancies. Paediatric GIST have an annual incidence of 0.02 per million children, have a female predisposition, are usually located in the stomach (50–60%) and in up to 85% of cases CD117-cKit or PDGFRA mutation is absent, resulting in a decreased efficacy of the target therapy.

Case description

We report the case of an incidentally diagnosed gastric GIST in a 14-year-old boy with multiple malformations. Genetic tests and Kariotype resulted negative.

Recently, an abdominal US visualized an hypoechoic heterogeneous abdominal mass. The common tumor markers resulted negative and the abdominal CT-scan confirmed the presence of a solid round lesion (42×36mm) in contact with the stomach and the pancreas. Laparoscopy allowed the recognition and the removal of the nodular mass at the posterior margin of the stomach. The histopathologic and the molecular biology findings were consistent with a kit-wilde type GIST. Surgical margins were microscopically free of tumor cells.

These results justify the decision not to add other surgical or medical therapy. However, for high risk of recurrence and metastasis, a close follow-up was started.

Discussion and evaluation

GIST are asymptomatic in 10% to 30% of patients or present nonspecific symptoms and signs. These tumors present usually irregular, lobulated and ulcerated. CT-scan of the abdomen and pelvis or magnetic resonance imaging (MRI) are mandatory in the diagnostic work-up. The final diagnosis is based on histology and immunohistochemistry. Surgery is the first-line treatment in patients with localized disease.

Conclusion

Guidelines for the management of pediatric GIST are not presently available for the paucity of reports and data. However it is widely accepted that surgery is the first-line treatment and gross resection with negative microscopic margins can be considered therapeutic and lead to full remission of the pathology. Laparoscopy is a safe surgical approach for the exploration of the abdominal cavity, the evaluation of the disease and the complete removal of the tumor.

Unique case of sporadic multiple gastro intestinal stromal tumour

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and they derived from transformed neoplastic precursors of Cajal's interstitial cell (ICC).

PRESENTATION OF THE CASE

We are presenting a sporadic and exemplary case of 42 multiple GISTs in a young female patient. Our patient showed anemia for the gastric GIST bleeding and only after other tumors were instrumentally and intra-surgery discovered. The patient showed genetic mutation V559A/1676 T>C of the juxtamembrane domain of the exon 11 causing the replacement of Valine with Alanine in the 559 codon.

DISCUSSION

GISTS estimated annual incidence is 12-14 per million. Multiple GISTs associated with familiarity or hereditary syndromes are described only in few case reports and sporadic mGISTs have not been studied yet. Literature review has been done.

CONCLUSION

We are presenting a sporadic and exemplary case of 42 multiple GISTs in a young female patient localized trough out all the gastrointestinal tract. This is the only case of sporadic multiple GISTs reported in literature.

Small intestinal gastrointestinal stromal tumor in a young adult woman: a case report and review of the literature

Introduction

Gastrointestinal stromal tumor is the most common sarcoma of the gastrointestinal tract. We report a case of gastrointestinal stromal tumor in a small intestine, initially suspected for leiomyosarcoma given that gastrointestinal stromal tumors in young adult patients are limited due to their rarity.

Case presentation

A 30-year-old Caucasian ethnic Albanian woman from Kosovo presented with abdominal pain, nausea and vomiting. Subsequently, the tumor was detected in her small intestine, as an infiltrating mass approximately 10cm in diameter. The tumor was resected en bloc and duodenojejunal terminal-terminal anastomosis was performed. The tumor was a large, bulky, intramural mass, with fish-flesh to tan-brown appearance, as well as with foci of hemorrhage and necrosis. On histological examination the tumor showed transmural growth, deep infiltrative pattern and malignant feature, with mitotic count >5 per 50 high-power field, dense cellularity with plump spindle cells, and with eosinophilic cytoplasm within variably hyalinized and edematous stroma, skeinoid fibers (extracellular collagen globules) and foci of hemorrhage. In addition, the tumor was composed of areas with epithelioid morphology. The immunohistochemistry results showed high expression of proto-oncogene c-kit, CD117, CD34 and vimentin, whereas α-smooth muscle actin was focally positive. Desmin and S-100 protein were negative.

Conclusions

Gastrointestinal stromal tumor should be included in the differential diagnoses of intestinal mesenchymal tumors presenting as a single mass in young female adults. Given that gastrointestinal stromal tumors in young adults represent a more heterogeneous group than gastrointestinal stromal tumor in pediatric cases, more effort should be made to investigate its pathogenesis and potentially more specific treatment.