C-kit Negative GIST

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract, originating from structures differentiating towards Cajal cells. Due to their morphology and localization, the extragastrointestinal stromal tumors (EGISTs) can be a diagnostic challenge. We investigated a series of 51 EGISTs diagnosed in our institutions, aiming to explore the immunophenotypes and to analyze the process and the utility of the antibodies required for a positive diagnosis. Immunohistochemical examinations were done for pan-cytokeratin (pan-CK), Ki67, discovered on GIST1 (DOG1) protein and platelet-derived growth factor receptor alpha (PDGFRA), as necessary...

BACKGROUND: Esophageal gastrointestinal stromal tumors (E-GISTs) are often diagnosed early due to complaints such as dysphagia and are rarely found to be huge in size. Here, we report the treatment of a case of huge E-GIST successfully resected by minimally invasive surgery after neoadjuvant imatinib therapy. CASE PRESENTATION: An 86-year-old male patient with a 3-month history of dysphagia was referred to our hospital because of a suspected mediastinal tumor on chest X-ray...

Gastric plexiform fibromyxoma is extremely rare. In our case, upper gastrointestinal endoscopy of a 41-year-old woman patient revealed a 1-cm submucosal tumor (SMT) in the greater curvature of the lower body of the stomach. On contrast-enhanced computed tomography, the tumor was hypervascular in the arterial phase with continuous enhancement in the post-venous phase. On endoscopic ultrasonography, it had a low echo pattern. The preoperative diagnosis was a gastric SMT with a rich vasculature; however because the biosy specimen did not contain tumor tissue, a malignant tumor could not be excluded...

BACKGROUND: Neurofibromatosis type 1 is an inherited cancer predisposition syndrome that is caused by a mutation in the NF1 gene that encodes neurofibromin. Patients with neurofibromatosis type 1 have a higher risk of gastrointestinal stromal tumor. This study reports the case of a patient with gastrointestinal stromal tumor who was later diagnosed to have neurofibromatosis type 1 and, unlike usual features, had some uncommon features such as occurrence at an early age and unusual site of origin...

BACKGROUND: Gastrointestinal stromal tumors (GISTs), which are the most common soft tissue tumors of the gastrointestinal tract, originate from Cajal interneurons. The main metastatic sites of GISTs are the liver and intra-abdominal cavity, and metastasis to the heart is rare. CASE PRESENTATION: The patient was a 78-year-old man who was diagnosed with a rectal GIST 20 years previously. Since then, he had undergone repeated operations for metastasis. A follow-up thoracoabdominal computed tomography scan 4 months prior to the operation revealed GIST metastasis to the left ventricular myocardium...

PURPOSE: We present a case of a gastrointestinal stromal tumor (GIST) metastasis of the rectal primary resisting chemotherapy to the right orbit 15 years after excision of the primary lesion. OBSERVATIONS: A 79-year-old man was diagnosed with rectal GIST at the age of 65 years and underwent rectal amputation. He underwent hepatectomy for GIST liver metastases at the age of 69 years and pericardiectomy for GIST pericardial metastases at 72 years of age. At the age of 79 years, positron emission tomography-computed tomography revealed the possibility of liver metastasis and metastasis to the right orbit of 10 mm in size...

PURPOSE: Evaluate ponatinib for advanced gastrointestinal stromal tumors (GIST). PATIENTS AND METHODS: This single-arm phase 2 trial enrolled patients with metastatic and/or unresectable GIST with failure of prior tyrosine kinase inhibitor (TKI) treatment into two cohorts based on presence or absence of KIT exon 11 (ex11) primary mutations. Patients initially received ponatinib 45 mg once daily. Following a temporary clinical hold in October 2013, dose reductions were implemented to reduce risk of arterial occlusive events (AOEs)...

The patient was a 43-year-old man. An upper gastrointestinal endoscopic examination revealed a gastric submucosal tumor(SMT)-like, elevated 8-mm lesion in the greater curvature of the upper body of the stomach. It was diagnosed as spindle cell tumor on the basis of biopsy findings, and a gastrointestinal stromal tumor(GIST)was suspected. Various immunohistochemical staining techniques were used; however, a definitive diagnosis could not be achieved. There was no evidence of distant metastasis even on thoracoabdominal computed tomography imaging; thus, the patient was referred to our department for definitive diagnosis and surgical treatment...

A 67-year-old male patient was referred to our department for fecal occult blood in March 2019. In April, lower intestinal endoscopic examination revealed a 25-mm pedunculated polyp in the sigmoid colon. Endoscopic mucosal resection was then performed. The pathological diagnosis was tub1-tub2 with an invasion depth of pT1b 3,000 μm, and ly0 and v1 vascular invasion. The tumor marker levels were normal, with CEA of 1.1 ng/mL and CA19-9 of 13.9 U/mL. An additional laparoscopic low anterior resection and D2 dissection were performed in June...

BACKGROUND: Schwannomas, also known as neurinomas, are tumors that derive from Schwann cells. Gastrointestinal schwannomas are extremely rare, but the stomach is the most common site. Gastric schwannomas are usually asymptomatic. Endoscopy and imaging modalities might offer useful preliminary diagnostic information. However, to diagnose schwannoma, the immunohistochemical positivity for S-100 protein is essential, whereas CD117, CD34, SMA, desmin, and DOG-1 are negative. CASE SUMMARY: A 45-year-old female was found to have a gastric mass during a medical examination, which was diagnosed as a gastric schwannoma...

Gastrointestinal stromal tumor (GIST), the most common mesenchymal tumor of the human gastrointestinal tract, differentiating toward the interstitial cell of Cajal (ICC), arises predominantly in the stomach and small intestine. Small intestinal GISTs appear to have worse prognosis than gastric GISTs. In a pilot study of a cDNA expression chip using several GISTs, we found that Cell Adhesion Molecule 1 (CADM1), which could contribute to tumor growth and infiltration, is expressed more strongly in small intestinal GISTs than gastric GISTs...

OBJECTIVES: This study aimed to report the clinicopathological features, management and long-term outcomes of patients with gastrointestinal stromal tumours (GISTs) in Oman. METHODS: This retrospective study was conducted on patients treated for GIST between January 2003 and December 2017 at three tertiary referral centres in Muscat, Oman. All patients with confirmed histopathological diagnoses of GIST and followed-up at the centres during this period were included...

We report a rare case of KIT-negative extra-gastrointestinal stromal tumor, in a 40-year-old woman. Contrast-enhanced computed tomography and magnetic resonance imaging revealed a >15-cm mass of multiple cystic lesions in the greater omentum. Histopathological findings after surgery showed a sheet-like growth of stellate tumor cells from epithelial cells, cystic degeneration, and mucus-like stroma. Immunohistochemistry was positive for discovered on GIST-1 (DOG1) but negative for CD117 (c-kit).

BACKGROUND: Leiomyosarcoma is a rare tumor that could originate from the gastrointestinal tract, uterus, kidney, retroperitoneum, and the soft tissues of the extremities. It accounts for only 1% of all gastrointestinal mesenchymal tumors and primary leiomyosarcoma of the stomach is extremely rare. Most cases reported as leiomyosarcoma of the stomach before the development of KIT immunohistochemistry might be gastrointestinal stromal tumors (GISTs) of the stomach and only 18 cases of leiomyosarcoma of the stomach have been reported since early 2000s...

The patient was a 62-year-old man diagnosed as having prostatic extra-gastrointestinal stromal tumor (EGIST) who was treated with imatinib. No recurrence or metastasis was found after a 6-month follow-up. We identified 14 cases of prostatic primary EGIST in PubMed and summarized these cases with our case. The patients' ages ranged from 31 to 78 years (average: 53.6 years), and most patients' prostate-specific antigen (PSA) concentrations were within normal limits (92.9%, 13/14). All patients underwent imaging examinations; prostatic masses measured 6 to 14...

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. Dedifferentiation in these tumours occurs rarely, and when it does occurs most commonly after prolonged treatment with imatinib. We report the case of a 64-year-old man who presented with a mass of 8×7×3 cm dimensions involving the duodenum and head of the pancreas. On histopathology, areas of anaplastic tumour cells were negative for DOG-1, c-kit, CD-34, desmin and panCK along with a molecular level study showing wild-type KIT and PDGFRA (platelet-derived growth factor receptor alpha) gene...

Gastrointestinal stromal tumors (GISTs) are common neoplasms of the gastrointestinal tract that can be treated successfully using C-kit target therapy and surgery; however, imatinib chemoresistance is a major barrier to success in therapy. The present study aimed to discover alternative pathways in imatinib-resistant GISTs. Long noncoding RNAs (lncRNAs) are newly discovered regulators of chemoresistance. Previously, we showed that the lncRNA HOTAIR was upregulated in recurrent GISTs. In this study, we analyzed differentially expressed lncRNAs after imatinib treatment and found that HOTAIR displayed the largest increase...

Desmoid tumours, also known as aggressive fibromatosis, are fibromuscular neoplasms that arise from mesenchymal cell lines. Desmoid tumours are usually benign and are locally aggressive tumours. We report a case of a 31-year-old man presenting with abdominal mass associated with dyspepsia and early satiety. CT scan demonstrated a large heterogeneous mass adherent to or arising from the jejunum. The patient underwent a successful elective exploratory laparotomy with resection of the tumour arising from the wall of the ileum with a 10 cm margin...

Gastrointestinal stromal tumors (GISTs) are the dominant mesenchymal tumors of the digestive tract. Extragastrointestinal stromal tumors (EGISTs) usually originate outside the gastrointestinal tract without connection to the gastric or intestinal wall. However, EGISTs arising from the vaginal wall are very rare. Here, we report a case of EGIST that occurred in the vagina of a 60-year-old woman. The tumor was present in the posterior vaginal wall. It was surgically excised, and histological examination revealed spindle cell morphology with up to 14 mitoses per 50 high power field (HPF) and necrosis with the tumor-negative margins...

The patient was a 77-year-old woman. She underwent a partial gastrectomy at the age of 40, and a partial colectomy at the age of 75 following a diagnosis of a carcinoid. In November 2019, a 1.5 cm mass with a clear boundary was found in the pancreatic tail, which was strongly stained uniformly. And furthermore, multiple masses between 2 cm and 3 cm with a clear boundary was found inside liver segment S1 and S6 and S7 and S8 on CT, which was strongly stained at the edge in the early phase and was seen as a low density area in the late phase...