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81.
Rearrangements of the RET receptor tyrosine kinase gene generating RET/PTC oncogenes are specific to papillary thyroid carcinoma (PTC), the most frequent thyroid tumor. Here, we show that the RET/PTC1 oncogene, when exogenously expressed in primary normal human thyrocytes, induces the expression of a large set of genes involved in inflammation and tumor invasion, including those encoding chemokines (CCL2, CCL20, CXCL8, and CXCL12), chemokine receptors (CXCR4), cytokines (IL1B, CSF-1, GM-CSF, and G-CSF), matrix-degrading enzymes (metalloproteases and urokinase-type plasminogen activator and its receptor), and adhesion molecules (L-selectin). This effect is strictly dependent on the presence of the RET/PTC1 Tyr-451 (corresponding to RET Tyr-1062 multidocking site). Selected relevant genes (CCL20, CCL2, CXCL8, CXCR4, L-selectin, GM-CSF, IL1B, MMP9, UPA, and SPP1/OPN) were found up-regulated also in clinical samples of PTC, particularly those characterized by RET/PTC activation, local extrathyroid spread, and lymph node metastases, when compared with normal thyroid tissue or follicular thyroid carcinoma. These results, demonstrating that the RET/PTC1 oncogene activates a proinflammatory program, provide a direct link between a transforming human oncogene, inflammation, and malignant behavior.  相似文献   
82.
Rationale:Inflammatory myofibroblastic tumor (IMT) is a rare mesenchymal tumor that is prevalent among children and adolescents. Surgery is the most important therapeutic approach for IMT and complete resection is recommended. Although 50% of IMTs show anaplastic lymphoma kinase (ALK) rearrangements, crizotinib has proven an effective therapeutic approach. However, the genetic landscape of this tumor is still not fully understood and treatment options are limited, especially in the majority of ALK-negative tumors.Patient concerns:We describe the clinical case of a healthy 18-year-old female in whom a pulmonary nodule was incidentally detectedDiagnoses:Following a small increase in the size of the nodule, the patient underwent both 18FDG-PET/CT and 68Ga-PET/CT, resulting in a suspicion of bronchial hamartoma.Interventions:The patient underwent surgery and a salivary gland-like lung tumor was diagnosed.Outcomes:After surgery, the patient was referred to our cancer center, where a review of the histology slides gave a final diagnosis of ALK-negative lung IMT. Given the histology, it was decided not to administer adjuvant therapy and the patient was placed in a 3-monthly follow-up program. The patient is still disease-free 2 years post-surgery.Lessons:Although there is no standard of care for the treatment of IMT, identifying genomic alterations could help to redefine the management of patients with negative-ALK disease. Our review of the literature on IMT and other kinase fusions revealed, in addition to ALK rearrangements, the potential association of ROS1, NTRK, RET, or PDGFR beta alterations with the tumor.  相似文献   
83.
Digestive Diseases and Sciences - Mesenteric cysts are defined as a heterogeneous group of intra-abdominal cystic lesions of the mesentery or omentum that may be found in any portion of the...  相似文献   
84.
Analysis of 786 NF1 mutation-positive subjects with clinical diagnosis of neurofibromatosis type 1 (NF1) allowed to identify the heterozygous c.5425C>T missense variant (p.Arg1809Cys) in six (0.7%) unrelated probands (three familial and three sporadic cases), all exhibiting a mild form of disease. Detailed clinical characterization of these subjects and other eight affected relatives showed that all individuals had multiple cafè-au-lait spots, frequently associated with skinfold freckling, but absence of discrete cutaneous or plexiform neurofibromas, Lisch nodules, typical NF1 osseous lesions or symptomatic optic gliomas. Facial features in half of the individuals were suggestive of Noonan syndrome. Our finding and revision of the literature consistently indicate that the c.5425C>T change is associated with a distinctive, mild form of NF1, providing new data with direct impact on genetic counseling and patient management.  相似文献   
85.
Gastrointestinal stromal tumour (GIST) is a rare tumour of the gastrointestinal tract which does not generally originate in the rectum. The authors describe a case of a 70-year-old man who underwent an anterior resection of the rectum for a low-risk GIST. The patient was not given adjuvant chemotherapy with imatinib and is still disease-free 30 mo after surgery. The authors conclude that although rectal GIST is extremely uncommon, it should be included in differential diagnosis when a tumour in the rectum is detected. Biopsy of the tumour is essential, since this makes it possible to reach a sure preoperative diagnosis based on the immunohistological features of the CDl17 and CD34. Although complete surgical resection with negative tumour margins is the principal curative procedure for primary and nonmetastatic tumours, further studies are still needed for the determination of the most effective treatment strategy for patients with rectal GIST.  相似文献   
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OBJECTIVE: To evaluate the reliability of contrast-unenhanced power Doppler (CUPD) and contrast-enhanced power Doppler (CEPD) ultrasound (US) assessment of synovial vascularity of knee joint synovitis by prospective comparison with the "gold standard," arthroscopy. METHODS: A total of 18 knees of 17 patients with refractory rheumatoid and psoriatic knee joint synovitis were examined by US. Recognition of PD synovial vessel flow and its spatial arrangement in relation to the pannus/cartilage interface (P/CI) or fluid/synovium interface (F/SI) were studied by CUPD- and CEPD-US after a single intravenous bolus of galactosel palmitic acid (Levovist). Arthroscopy video recordings were reanalyzed by computer image analysis to assess synovial vascular marking. CUPD and CEPD flow signal scores were compared with each other and with corresponding vascular marking scores. Using villous vascular marking as reference, CUPD and CEPD sensitivity and specificity were measured. Interobserver variability was evaluated. RESULTS: Compared with the unenhanced PD method, contrast administration increased the PD flow signal score in 13/18 knees (72.2%), allowing increased detection of F/SI PD flow signal configuration (p < 0.018) and of the coexistence of P/CI and F/SI PD imaging (p < 0.0078). With arthroscopy as reference, contrast-enhanced PD was found to be more useful than the unenhanced method, showing more reproducible PD signal scores (p = 0.05 vs p = nonsignificant), as well as higher sensitivity (80% vs 30%), but lower specificity (62% vs 87%), in the recognition of increased vascularity of synovial villi. Interobserver agreement was 100%. CONCLUSION: The prospective comparison with arthroscopy showed the reliability of the CEPD method in synovial vessel recognition and its potential clinical usefulness in assessment of knee joint synovitis.  相似文献   
88.
Although surgery alone represents a curative approach for patients with pT3N0M0 colon cancer, about 15–20 % of these patients develop a relapse of disease. Microsatellite instability (MSI) is one of the most important molecular markers in colorectal cancer. The aim of this study was to investigate the prognostic relevance of MSI in all pT3N0M0 tumors recorded in the Cancer Registry of the Province of Modena—(Northern Italy) within the 2002–2006 period in patients who showed a relapse of disease during the 5-year period of follow-up (59 cases). They were compared to 59 controls similar in clinical and pathological features but with good prognosis. None of the subjects received adjuvant chemotherapy. MSI status was tested using BAT25, BAT26, NR24, and CAT25 fluorescent-labeled mononucleotide markers. The overall prevalence of MSI was 12.7 % (15 of 118 cases). MSI was detected mainly in mucinous adenocarcinoma (p < 0.003), in high-grade tumors (p < 0.008), in right-sided neoplasms (p < 0.005), and in patients with a better prognosis, though the difference was not statistically significant (11/59 patients ?18.6 % vs 4/59 patients ?6.7 %; OR 0.36 CI 95 % 0.11–1.15; p = 0.08). However, in multivariate analysis, MSI status becomes the strongest independent factor associated with relapse (OR 0.21, CI 95 % 0.06–0.81; p = 0.023), together with mucinous histological type (OR 0.40, CI 90 % 0.18–0.92). MSI is a relevant prognostic factor in stage pT3N0M0 colon cancer suitable to discriminate those patients with a high risk of relapse.  相似文献   
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