Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gastrointestinal stromal tumors (GISTs) are rare neoplasms arising from connective tissue elements of the gastrointestinal wall. They show a great heterogeneity with respect to their histogenetic, morphologic and prognostic characteristics. GISTs are known with myoid, neural or mixed features of differentiation. Clinical findings are gastrointestinal bleeding, abdominal pain and weight loss. We report on the case of a 50-year-old male patient who presented with melena and acute anemia (hemoglobin 10.5 g/dl). Esophagogastroduodenoscopy revealed a broad-based, centrally ulcerated polypoid formation of 3 cm in the gastric corpus as the cause of the upper gastrointestinal bleeding. Multiple endoscopic biopsies were negative for neoplastic changes. Because of no tendency of healing after triple eradication therapy of Helicobacter pylori and following proton pump inhibitor medication, the patient underwent distal gastrectomy with gastrojejunostomy. GIST of combined smooth muscle and neural type was diagnosed by histological and immunohistochemical examination. The features with increased mitotic activity and cellularity were those of a borderline stromal tumor. 6 months after surgery the patient is well with no signs of residual malignancy. This case demonstrates that rare stromal neoplasms have to be taken into account in the differential diagnosis of gastrointestinal tumors even if endoscopic biopsies are negative for neoplastic changes. Because of the uncertain biological behavior of the GISTs an early surgical intervention is recommended.
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PMID:Gastric stromal tumor--a rare cause of an upper gastrointestinal bleeding. 1147 2

We describe herein an extremely unusual case of a gastrointestinal stromal tumor (GIST) of the lesser omentum. A 45-year-old man was admitted to our hospital with an intra-abdominal mass that was subsequently misdiagnosed as a submucosal tumor of the stomach. The tumor arose from the lesser omentum and was removed without difficulty. Histologically, the tumor was composed of spindle-shaped cells with an interlacing bundle pattern, and immunohistochemical examination showed that it was positive for myeloid stem cell antigen (CD34), but negative for HHF35 and S-100 protein. These findings were consistent with a GIST lacking myogenic features and neural attributes. The patient had an uneventful postoperative course, and was free of recurrence when last seen 11 months after his operation.
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PMID:Gastrointestinal stromal tumor of the lesser omentum: report of a case. 1151 Jun 10

We report herein the case of a 77-year-old woman with a gastrointestinal stromal tumor (GIST) of the duodenal ampulla. The tumor, which was removed by pancreatoduodenectomy due to its malignant potential, showed expansive growth in the muscular coat of the duodenal ampulla. Histologically, the tumor cells were spindle-shaped or round, and exhibited fascicular or storiform growth pattern with frequent mitotic figures. The immunohistochemical and ultrastructural results suggested that the tumor may have originated from the interstitial cells of Cajal in the muscular coat of the duodenal ampulla. To our knowledge, this is the first case of malignant GIST of the duodenal ampulla to be reported in Japan.
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PMID:Gastrointestinal stromal tumor of the duodenal ampulla: report of a case. 1151 Jun 12

Mutations in the c-KIT receptor occur somatically in many sporadic Gastrointestinal Stromal Tumors (GIST), and similar mutations have been identified at the germline level in kindreds with multiple GISTs. These mutations activate the tyrosine kinase activity of c-KIT and induce constitutive signaling. To investigate the function of activated c-KIT in GIST, we established a human GIST cell line, GIST882, which expresses an activating KIT mutation (K642E) in the first part of the cytoplasmic split tyrosine kinase domain. Notably, the K642E substitution is encoded by a homozygous exon 13 missense mutation, and, therefore, GIST882 cells do not express native KIT. GIST882 c-KIT protein is constitutively tyrosine phosphorylated, but tyrosine phosphorylation was rapidly and completely abolished after incubating the cells with the selective tyrosine kinase inhibitor STI571. Furthermore, GIST882 cells evidenced decreased proliferation and the onset of apoptotic cell death after prolonged incubation with STI571. Similar results were obtained after administering STI571 to a primary GIST cell culture that expressed a c-KIT exon 11 juxtamembrane mutation (K558NP). These cell-culture-based studies support an important role for c-KIT signaling in GIST and suggest therapeutic potential for STI571 in patients afflicted by this chemoresistant tumor.
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PMID:STI571 inactivation of the gastrointestinal stromal tumor c-KIT oncoprotein: biological and clinical implications. 1152 90

We present six cases of successfully resected primary tumors of the distal part of duodenum (third and fourth segment). Average age of the four male and two female patients was 59 years (47-80). Distal segmental resection were performed in four, pylorus-preserving pancreatoduodenectomy in two cases. Histologically the tumors were five adenocarcinomas, and one gastrointestinal stromal tumor. This tumor causing massive bleeding. In two patients, local lymph nodes were tumor positive, and in one patient synchronous metastasis of the greater omentum was excised during a palliative resection. There was no operative mortality. During a mean follow-up period of 17 months two patients died. Our results support the fact, that radical surgical resection of these tumors, even by segmental resection, provides a more favorable prognosis for duodenal carcinoma than for pancreatic tumors.
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PMID:[Surgical resection of tumors in the distal duodenum]. 1155 Apr 87

The reduced incidence of gastric cancer, due to a better patients surveillance and more accurate understanding of prophylactic measure, has allowed a detection of early stages as well as cancers with different origin cells. Either the difficulty of differential diagnosis or the various surgical and integrated approaches, make these neoplasm hard to enroll in standard treatment protocols. Our experience consists of 5 clinical cases with four different histology: lymphoma, leiomioma, carcinoid and gastrinoma. A rare case of secondary involvement of the stomach by an adrenal adenocarcinoma is also described. Lymphomas benefit of the surgical therapy only in early stages (IE, IIE), eventually associated to chemio- and radiotherapy, in relationship with local diffusion of the disease; gastric resection is more supported than gastrectomy. Polychemotherapy, with or without radiotherapy, is used for advanced stages (IIIE and IVE), leaving to surgery the role of controlling hemorrhagic or occlusion compliances. GIST have a different therapeutic approach: surgery represents the only choice since chemio- and radiotherapy have no benefits for the biological characteristics of such neoplasm. Surgery is the ideal choice for the carcinoids with some indications for chemio radiotherapy in the palliative surgery or in the relapsing. We emphasize the rarity of the secondary gastric neoplasm coming from the suprarenal glands. We analyze our diagnostic and therapeutic protocols, comparing them with the current literature.
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PMID:[Direct experience in the treatment of unusual, primary, and secondary malignant tumors of the stomach]. 1155 72

A 70 year-old male was seen at the hospital with the chief complaints of frequent miction and incomplete urinary retention. A hen's egg-sized firm mass was palpable in anterior wall of rectum by digital rectal examination. Intravenous urography showed severe bilateral hydronephroureter. Transrectal ultrasound, CT scan and MRI revealed a mass with 5 cm in diameter between prostate and rectum, and the margin of them were unclear. On needle biopsy of the tumor, leiomyosarcoma of the prostate was suspected. We performed radical cytectomy and created continent urinary reserver. Because the tumor and rectum could not be lysed, part of the rectum was resected. Histological examination showed gastrointestinal stromal tumor (GIST) of rectum. GIST of rectum is a rare entity, and in case of contact with the prostate, it is difficult to differentiate from leiomyosarcoma of prostate.
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PMID:[A case of gastrointestinal stromal tumor of rectum, difficult to differentiate from leiomyosarcoma of prostate]. 1159 5

A case of gastrointestinal stromal tumor (GIST) of the stomach is reported. GIST has been applied to gastrointestinal submucosal tumors mainly composed of spindle shaped cells that represent neither typical features of myogenic nor neurogenic tumors, and immunohistochemical studies are necessary for the diagnosis of GIST. The patient was a 39-year-old man and was successfully diagnosed to be GIST (uncommitted type) preoperatively by immunohistochemical studies of biopsy specimens from an ulcerative submucosal tumor with bridging folds in the fundus, approximately 3.0 cm in size. Local excision of the stomach was performed. This is the 3rd case of GIST with a preoperative diagnosis to appear in the literature in Japan. For gastroenterological surgeons, it is critical to select the most suitable surgical procedure. In the present, because the number of papers reporting GIST of the stomach is small, it is impossible to review GIST clinicopathologically. We reviewed the surgical procedure for gastric leiomyosarcomas, because of including many cases with GIST in them. Therefore, we performed 54 cases of gastric GIST in the literature, compared with 92 cases of gastric leiomyosarcoma. As a result, it was thought that local excision for gastric GIST should be preferred.
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PMID:Gastrointestinal stromal tumor of the stomach diagnosed preoperatively. 1159 31

Tyrosine kinases are enzymes that regulate mitosis, differentiation, migration, neovascularization, and apoptosis. Their spectrum and association with specific malignancies offer multiple targets for therapeutic intervention. Chronic myelogenous leukemia (CML) represents an ideal target for a therapy using a selective inhibitor of the BCR-ABL tyrosine kinase. The 2-phenylpyrimidine derivative STI571 was rationally designed to inhibit ABL and BCR-ABL tyrosine kinase activities through competitive ATP-binding pocket interactions. Phase II data demonstrate hematologic and cytogenetic responses in interferon refractory chronic-phase, accelerated-phase and blast crisis patients. However, long-term observation is needed to confirm that response data result in prolongation of survival. STI571 is being studied in other malignancies, including leukemias characterized by expression of alternate molecular forms of BCR-ABL and those expressing protein tyrosine kinases with ATP-binding pockets structurally similar to ABL, e.g. c-kit and PDGF-R. Gastrointestinal stromal tumor (GIST) cells overexpress the stem cell factor receptor CD117, the product of the proto-oncogene c-kit. Inhibition of c-kit in vivo results in an immediate metabolic change of the tumor cells, detectable by positron emission tomography. Since c-kit overexpression is inhibited in small-cell lung cancer cell lines, a study with STI571 as second-line therapy of c-kit-positive small-cell lung cancer is in progress. Clinical studies are ongoing in malignancies associated with an enhanced activity of the PDGF-R, such as highgrade glioma, prostate cancer and leukemias with rearrangements of PDGF-R. The development of selective tyrosine kinase inhibitors is considered a promising approach for the design of new drugs. Clinical responses to STI571 in various malignancies may stimulate greater interest in the clinical use of tyrosine kinase inhibitors.
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PMID:[Selective inhibition of tyrosine kinases - a new therapeutic principle in oncology]. 1160 Aug 16

A case of gastrointestinal stromal tumor (GIST) in stomach was presented. Serial barium meal x-ray examinations revealed an enlarging elevated lesion on the fornix of the stomach. Tumor volume doubling time was found to be 299 days. Microscopic and immunohistochemical studies of the resected tumor disclosed GIST, uncommitted type, low grade malignant/potentially malignant. A radiographic feature of this rare type of gastric submucosal tumor was demonstrated in this report.
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PMID:Radiographic observation of a case of gastrointestinal stromal tumor in stomach. 1168 Sep 40


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