1/6. Gastrointestinal stromal tumour of the colon presenting with intestinal obstruction.Gastrointestinal Stromal Tumours are the commonest mesenchymal tumors of the gastrointestinal tract, the stomach and small intestine being the favored sites. They rarely occur in the colon and rectum and esophagus. The diagnosis is difficult, especially in the rarer sites, since there are no pathognomic features to suggest GIST on preoperative clinical examination and investigations, and only a detailed histopathological analysis of the specimen reveals their true nature. The case of a young female patient who presented with intestinal obstruction due a GIST of the transverse colon is reported. The relevant literature is briefly reviewed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/6. A case of a gastrointestinal stromal tumour presenting as acute abdomen.BACKGROUND: Gastrointestinal stromal tumour (GIST) has many modes of presentation. This is the first reported GIST presenting as an acute abdomen. methods: A man presented with signs and symptoms suggestive of acute appendicitis. Examination under anaesthesia revealed a mass. At laparotomy a strangulated mass was found originating from the greater curve of the stomach. Subsequent histopathology confirmed this to be a gastrointestinal stromal tumour, probably of a benign nature. Post-operative investigations did not show any metastatic spread. CONCLUSIONS: GISTs arise from the gastrointestinal tract, omentum, and mesentery. Presentation is generally non-specific and it is rare for them to present acutely. Management should include staging to exclude any metastatic spread.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/6. Spontaneous rupture of recurrent gastrointestinal stromal tumor associated with neurofibromatosis type 1.The incidence of gastrointestinal stromal tumor (GIST) among neurofibromatosis type 1 (NF-1) patients is approximately 3.9-25%, and this relationship is generally considered to be non-coincidental. We report a patient with NF-1 who underwent laparotomy 3 times due to recurrent intra-abdominal tumor rupture with internal bleeding in the space of 13 years. The pathologic diagnoses were schwannoma, malignant peripheral nerve sheath tumor and GIST. Because of the similar histologic features of these tumors, we considered them to be of the same nature. Immunohistochemical staining can help in the differential diagnosis. We suggest that NF-1 patients with gastrointestinal symptoms receive further survey to rule out GISTs.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/6. Response evaluation in gastrointestinal stromal tumours treated with imatinib: misdiagnosis of disease progression on CT due to cystic change in liver metastases.Imatinib is a highly effective treatment for patients with metastatic gastrointestinal stromal tumours (GIST). In most instances, response to imatinib treatment is assessed with CT. We present two cases where CT demonstrated the appearance of new low density liver lesions after 8-12 weeks of imatinib treatment. While this finding is consistent with progressive disease due to new lesions appearing at a previously uninvolved site, we hypothesise that the appearance of new liver lesions is in fact due to cystic change within previously occult, solid metastases. These untreated solid metastases were not visible on conventional portal phase CT due to their small size and vascular nature. Our hypothesis is supported by the observation that extrahepatic sites of disease had reduced in size over the same period of imatinib treatment and by the subsequent disease outcomes of these two cases. One patient, who continued imatinib because of significant symptomatic improvement despite the CT findings, remained stable on the same dose of imatinib for 18 months. The other patient, whose disease progressed when imatinib was withdrawn, had a dramatic response to treatment when imatinib was restarted at the same dose 2 years later. It is important that radiologists and oncologists who are involved in the management of GIST recognize that the appearance of new, low-density liver lesions on CT may represent a response to treatment. This finding must be correlated with symptomatic response and with tumour sites outside the liver before erroneously withdrawing effective imatinib treatment.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/6. Primary gastrointestinal stromal tumor in the retroperitoneum.Gastrointestinal stromal tumor (GIST) is the most frequent non-epithelial neoplasm in the gastrointestinal tract. GIST has received much attention both for its clinical significance and biological nature, while the retroperitoneal condition identical to GIST has been rarely described. Presented herein is a case of GIST arising from the retroperitoneum in a 67-year-old man. The solid tumor measuring 4 cm was uncovered in the retroperitoneum, between the abdominal aorta and inferior vena cava, on computed tomography. The patient underwent surgical excision of the tumor. Histological examination showed proliferating spindle cells in the clearly demarcated tumor; immunoreactivity for Kit and CD34 in tumor cells confirmed the diagnosis of GIST. The histological origin of GIST is suggested to be gastrointestinal pacemaker cells, because they share specific immunoreactivity for CD117/Kit, which is also relevant to pathogenesis of GIST. The present case was a rare primary GIST in the retroperitoneum with typical immunopathological features.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/6. hypothyroidism after sunitinib treatment for patients with gastrointestinal stromal tumors.BACKGROUND: Sunitinib malate is an oral tyrosine kinase inhibitor recently approved for the treatment of gastrointestinal stromal tumors and renal cell carcinoma. Because the ret proto-oncogene is also inhibited by this agent, clinical evaluation of thyroid function was performed. OBJECTIVE: To describe the prevalence and clinical presentation of thyroid dysfunction related to sunitinib therapy. DESIGN: Prospective, observational cohort study. SETTING: Tertiary care hospital. patients: 42 patients treated for a median of 37 weeks (range, 10 to 167 weeks). MEASUREMENTS: Following analysis of serial thyroid-stimulating hormone (TSH) measurements collected prospectively during a clinical trial of sunitinib, the authors determined the proportion of patients with thyroid dysfunction. RESULTS: Abnormal serum TSH concentrations were documented in 26 of 42 patients (62%): 15 (36%) developed persistent, primary hypothyroidism; 4 (10%) developed isolated TSH suppression; and 7 (17%) experienced transient, mild TSH elevations. The risk for hypothyroidism increased with the duration of sunitinib therapy. Six of 15 (40%) hypothyroid patients had suppressed TSH concentrations before developing hypothyroidism, suggesting thyroiditis. Two hypothyroid patients evaluated with thyroid ultrasonography had no visualized thyroid tissue despite normal baseline thyroid function. LIMITATIONS: The exploratory nature of this study precluded more frequent biochemical and sonographic analysis that may better define the mechanism of sunitinib-associated thyroid dysfunction. CONCLUSION: hypothyroidism is a frequent complication of sunitinib therapy. Regular surveillance of thyroid function is warranted in patients receiving the drug. Although the mechanism by which this complication occurs is unknown, the observations of preceding TSH suppression and subsequent absence of visualized thyroid tissue in some patients suggest that sunitinib may induce a destructive thyroiditis through follicular cell apoptosis. This provides a rationale for further investigation of sunitinib treatment in patients with advanced thyroid cancer.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |