C-kit Negative GIST

A 87-year-old female was pointed out wall thickness in the upper part of gastric body for examination of anemia. The mass had a contrast effect, some of it protruded outside the wall, and the surrounding lymph nodes were enlarged. Upper endoscopy showed irregular ulcerative lesion with submucosal volume from posterior wall to the greater curvature in the upper part of gastric body. Biopsy was performed, and GIST of stomach was diagnosed. Surgery was performed for the GIST of the stomach. During open surgery, invasion of pancreatic tail was observed, therefore proximal gastrectomy with D1 lymph node dissection and distal pancreatectomy were performed...

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) of the stomach is an uncommon mesenchymal neoplasm. We present a case of gastric submucosal tumor (SMT) where the final diagnosis was IMT. CASE PRESENTATION: A 69-year-old man presented with a 24-mm SMT on the posterior wall of the middle third of the stomach that was detected by screening upper gastrointestinal endoscopy. Abdominal contrast-enhanced computed tomography showed that the tumor was well-enhanced...

Gastric leiomyosarcoma is extremely rare. In this paper, we present a case of primary gastric leiomyosarcoma located in the fundus/cardia region. The tumoral spindle cells show diffusely moderate nuclear atypia, with focally marked atypia and rare mitotic figures. Additionally, the tumoral cells exhibit positive immunoreactivity to smooth muscle actin and desmin while testing negative for CD117 (c-kit). The tumor was successfully resected through a laparoscopic partial gastrectomy, and the patient experienced a full recovery...

BACKGROUND: An Inflammatory myofibroblastic tumor (IMT) is a rare intermediate malignancy characterized by myofibroblast proliferation and inflammatory cell infiltration. Various organs are the primary sites of origin. However, primary tumors originating in the stomach tend to be extremely rare, making the diagnosis difficult. Herein, we present a case of IMT originating in the stomach that was effectively managed using inverted laparoscopic endoscopic cooperative surgery (LECS). CASE PRESENTATION: A 47-year-old male who was admitted to the hospital because of a submucosal tumor that was discovered during upper gastrointestinal endoscopy...

BACKGROUND: Neoadjuvant imatinib is considered for gastrointestinal stromal tumors (GISTs) when decreased tumor size provides less extensive surgery and higher R0 resection rates. This study evaluates the effectivity and safety of neoadjuvant imatinib for large or locally advanced GIST. PATIENTS AND METHODS: From the prospective database of the Dutch GIST Consortium, all patients who underwent surgery after neoadjuvant imatinib at our center between 2009 and 2022 were selected...

BACKGROUND: Neurofibromatosis type 1 (NF1) is known to be associated with the frequent occurrence of unique gastrointestinal stromal tumors (GISTs), preferably occurring in the small intestine, with no mutations in the c-kit proto-oncogene or platelet-derived growth factor receptor-alpha (PDGFRA), with a high tendency for multifocal development, indolent nature, with low proliferation activity and favorable prognosis. CASE PRESENTATION: A woman in her forties visited her local doctor complaining of menstrual pain; a large mass was detected in her lower abdomen, and she was referred to our hospital...

The dedifferentiation of the gastrointestinal stromal tumors (GISTs) has been reported in a small number of cases, usually under the pressure of the tyrosine kinase inhibitor (TKI) treatment. Herein, we described a de novo dedifferentiated GIST with the SDH deficiency in a 32-year-old Chinese woman. The tumor was located on the lesser curvature of the gastric antrum, measuring 4.1x9.1 cm2 . Microscopically, the tumor was composed of 2 distinct morphological populations, mild epithelioid cells arranged in the multinodular growth pattern and hyperchromatic spindle cells arranged in the fascicular or sheet-like architecture...

INTRODUCTION AND IMPORTANCE: Extrahepatically growing hepatocellular carcinoma (HCC) account for only 0.3 %-2.4 % of all hepatocellular carcinoma cases. We present the rare case of a patient in whom endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) was used to distinguish an extrahepatically growing HCC from a gastric submucosal tumor. CASE PRESENTATION: The patient was a 44-year-old man who underwent an esophagogastroduodenoscopy (EGD) and was found to have a submucosal tumor (SMT)...

Extragastrointestinal stromal tumors (EGISTs) carry the same morphological, immunohistochemical and molecular features as gastrointestinal stromal tumors (GISTs) and involve extragastrointestinal tract soft tissue. The majority of reported EGIST cases arise from intraabdominal, retroperitoneal, or pelvic soft tissue. A significant subset of such tumors originates from the gastrointestinal muscle layer, grows in an exophytic manner, then loses attachment to the gastrointestinal tract. Consequently, true EGISTs are exceedingly rare...

BACKGROUND: Anaplastic lymphoma kinase (ALK) overexpression and gene alterations have been detected in several mesenchymal tumors, with significant implications for diagnosis, therapy and prognosis. However, few studies have investigated the correlation between ALK expression status and clinicopathological characteristics in patients with gastrointestinal stromal tumors (GISTs). METHODS: A total of 506 GIST patients were enrolled. Sanger sequencing was employed to detect c-KIT and PDGFRA gene mutations...

Dear editor, 50 years-old female with personal history of mutation of the gene BRCA1 and previous prophylactic double anexectomy consulted for rectal bleeding without pain since two weeks. A blood test was performed, with hemoglobin levels of 13.1g/dl and without iron deficiency. In the anal inspection there were neither external hemorrhoids nor anal fistulas, so a colonoscopy was requested. In the colonoscopy, all the colon mucosa was normal but, in the rectal retroflexion, apart from internal engorged hemorrhoids, surrounding the 50% of the anal opening an erythematous and indurated mucosa was found (figure 1)...

BACKGROUND: The current treatment paradigm of imatinib-resistant metastatic gastrointestinal stromal tumor (GIST) does not incorporate KIT/PDGFRA genotypes in therapeutic drug sequencing, except for PDGFRA exon 18-mutant GIST that is indicated for avapritinib treatment. Here, circulating tumor DNA (ctDNA) sequencing was used to analyze plasma samples prospectively collected in the phase III VOYAGER trial to understand how the KIT/PDGFRA mutational landscape contributes to tyrosine kinase inhibitor (TKI) resistance and to determine its clinical validity and utility...

BACKGROUND: Imatinib is the first-line adjuvant treatment for gastrointestinal stromal tumors (GISTs). Considering that some studies have suggested that imatinib (IM) plasma trough levels (Cmin ) change with time, the aim of this study is to assess the changes in IM Cmin in patients with GIST in a long-term study and to elucidate the relationships between clinicopathological features and IM Cmin . METHODS: In 204 patients with intermediate- or high-risk GIST who were taking IM, IM Cmin was analyzed...

AIM: This study investigates the clinicopathological features and prognostic genic biomarker factors of primary retroperitoneal extra-gastrointestinal stromal tumors (EGISTs). METHODS: The clinicopathological data of six patients with primary retroperitoneal EGIST were analyzed, including cell type (epithelioid or spindle), mitoses, and the presence of intratumoral necrosis and hemorrhage. Mitoses were counted and summed from 50 high power fields (HPFs). Mutations of exons 9, 10, 11, 13, 14, and 17 of the C-kit genes and those of exons 12 and 18 of the PDGFRA gene were examined...

Approximately 40 families with multiple gastrointestinal stromal tumors (GISTs) and germline c-kit gene mutations have been reported. Three knock-in mouse models have been generated, and all the models showed a cecal GIST. In the present study, we established a cell line derived from cecal GIST in a familial GIST model mouse with KIT-Asp818Tyr. Since the established cells showed spindle-shaped morphology with atypical nuclei, and since immunohistochemistry revealed that they were positive for α-SMA but negative for KIT, CD34 and desmin, the phenotypes of the cells were reminiscent of dedifferentiated GIST-like ones but not the usual GIST-like ones...

Upper GI bleeding from GIST is rare in Africa. The C-kit-negative variant is uncommon worldwide. We report a case of a 42-year-old woman managed for upper GI bleeding secondary to stomach GIST, negative for CD117 but positive for DOG 1 and CD 34. The 1-year postsurgery review is uneventful.

Schwannoma of the ascending colon is an extremely rare neoplasm that is often discovered incidentally in the asymptomatic older population on surveillance colonoscopy. We present the case of a symptomatic 22-year-old male presenting with one month of discomfort in the right lower abdominal quadrant, abdominal bloating, and hematochezia. A sessile polyp measuring 0.5 cm was identified in the ascending colon on the colonoscopy. The polyp was completely resected using cold snare polypectomy. Histological examination of the resected polyp with hematoxylin-eosin staining revealed small nodules of bland spindle cells with focal nuclear condensation...

INTRODUCTION: Melena is a common symptom of schwannoma of the small intestine, a rare type of tumor. Even more rare is schwannoma of the small intestine that requires a massive blood transfusion due to hemorrhage. Herein, we report such a case successfully treated with surgical resection. PRESENTATION OF CASE: A 72-year-old woman presented to the previous hospital with melena. The patient was taking antiplatelet drugs for a previous cerebral infarction. The patient had progressive anemia due to continuous melena...

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors, but are the most common mesenchymal tumors of the gastrointestinal tract. The risk classification of GISTs is based on the tumor size, mitotic index, tumor site, and presence of tumor rupture. Recurrence in the very-low-risk group is extremely rare. We herein report a case of liver metastases 2 years after resection of a very-low-risk duodenal GIST. CASE PRESENTATION: A 57-year-old woman presented to the hospital for evaluation of melena...

GIST is a rare soft tissue sarcoma, for which KIT and DOG1 are used as highly sensitive diagnostic markers. Other diagnostic markers include CD34, protein kinase C θ, deficiency of succinate dehydrogenase complex subunit B, carbonic anhydrase II, and type I insulin-like growth factor receptor. We investigated the role of TNS2 as a diagnostic biomarker by using immunohistochemistry in 176 GISTs and 521 other sarcomas. All GISTs expressed TNS2, with intermediate or high expression in 71.4% of samples. The majority (89...