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[en] The accuracy of preoperative MRI in detecting tumor extent has been evaluated in 35 patients with primary bone neoplasms; intra-osseous extent was measured on MR images and compared with macroslides of surgical specimens in 26 cases. An almost completely accurate prediction of tumor size was obtained with the combined employment of Spin-Echo (SE) and Short Inversion Time Inversion Recovery (STIR) sequences in the various tumors, with the exception of 2 Ewing's sarcomas. Changes in Signal Intensity (SI) and tumor morphology were identified in those cases which had undergone presurgical chemotherapy: the reduction in SI and in tumor size or the appearance of a more homogeneous signal was correlated with a positive response to cytotoxic therapy. MR imaging fully satisfies surgeon's preoperative requirements in the assessment of therapy-responding neoplasms as well as in local tumor staging in all types of neoplasms, with the exception of Ewing's sarcoma. (author). 30 refs.; 3 figs.; 1 tab
[en] To evaluate effects of a vascular-disrupting agent on rodent tumour models. Twenty rats with liver rhabdomyosarcomas received ZD6126 intravenously at 20 mg/kg, and 10 vehicle-treated rats were used as controls. Multiple sequences, including diffusion-weighted imaging (DWI) and dynamic contrast-enhanced MRI (DCE-MRI) with the microvascular permeability constant (K), were acquired at baseline, 1 h, 24 h and 48 h post-treatment by using 1.5-T MRI. [18F]fluorodeoxyglucose micro-positron emission tomography (18F-FDG μPET) was acquired pre- and post-treatment. The imaging biomarkers including tumour volume, enhancement ratio, necrosis ratio, apparent diffusion coefficient (ADC) and K from MRI, and maximal standardised uptake value (SUVmax) from FDG μPET were quantified and correlated with postmortem microangiography and histopathology. In the ZD6126-treated group, tumours grew slower with higher necrosis ratio at 48 h (P < 0.05), corresponding well to histopathology; tumour K decreased from 1 h until 24 h, and partially recovered at 48 h (P < 0.05), parallel to the evolving enhancement ratios (P < 0.05); ADCs varied with tumour viability and perfusion; and SUVmax dropped at 24 h (P < 0.01). Relative K of tumour versus liver at 48 h correlated with relative vascular density on microangiography (r = 0.93, P < 0.05). The imaging biomarkers allowed morphological, functional and metabolic quantifications of vascular shutdown, necrosis formation and tumour relapse shortly after treatment. A single dose of ZD6126 significantly diminished tumour blood supply and growth until 48 h post-treatment. (orig.)
[en] Highlights: ► miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. ► Ectopic restoration of miR-125b suppresses cell proliferation and migration in vitro. ► STAT3 is the direct and functional downstream target of miR-125b. ► STAT3 can bind to the promoter region of miR-125b and serves as a transactivator. -- Abstract: There is accumulating evidence that microRNAs are involved in multiple processes in development and tumor progression. Abnormally expressed miR-125b was found to play a fundamental role in several types of cancer; however, whether miR-125b participates in regulating the initiation and progress of osteosarcoma still remains unclear. Here we demonstrate that miR-125b is frequently down-regulated in osteosarcoma samples and human osteosarcoma cell lines. The ectopic restoration of miR-125b expression in human osteosarcoma cells suppresses proliferation and migration in vitro and inhibits tumor formation in vivo. We further identified signal transducer and activator of transcription 3 (STAT3) as the direct and functional downstream target of miR-125b. Interestingly, we discovered that the expression of miR-125b is regulated by STAT3 at the level of transcription. STAT3 binds to the promoter region of miR-125b in vitro and serves as a transactivator. Taken together, our findings point to an important role in the molecular etiology of osteosarcoma and suggest that miR-125b is a potential target in the treatment of osteosarcoma.
[en] Fifteen scalp masses consisting of five benign and ten malignant tumors were studied with ultrasound to evaluate its diagnostic role in scalp masses. Benign mass showed homogeneous echo pattern with smooth margin, Hand-Schuller-Christian disease(n=1) demonstrated solid mass in the diploic space eroding the outer table. The most of malignant tumors(9 of 10 cases) showed irregular margin, inhomogeneous echotexture, bone destruction, and intracranial extension. Dermatofibrosarcoma protuberans(n=1) revaled well defined hypoechoic solid mass with internal linear echoes. Ultrasonography considered as an initial noninvasive imaging modality for the evaluation of scalp masses
[en] Objective: To review the MR image findings in patients with neurofibromatosis type 1 (NF1) and to analyze the MR sequences and their diagnostic value so as to establish an adequate MR imaging protocol to supply the valuable imaging data for the diagnosis of NF1. Method: Thirty patients fulfilling the NIH diagnostic criteria for NF1 were examined with the following MR imaging protocol, which mainly included: Axial SE T2WI; Sagittal SE T1WI without contrast; Axial or Sagittal SE T1WI with contrast; Axial or Coronal FLAIR. At the same time the characteristics of the disease including sites, numbers, shapes, and changes of intensity and enhancement of the lesions were recorded and analyzed. Results: There were three forms of lesions being demonstrated on MRI: (1) Multiple intracranial hamartomas; Hyperintense lesions on T2WI and FLAIR images in 25 out of 30 patients (83%), which mainly located in the globus pallidum, cerebellums, and brainstems. There was no definite enhancement with Gadolinium. 20 out of 25 patients (80%) showed diffuse higher intensity in the region of hippocampus or para-hippocampus gyrus, thalamus, and around the aqueduct. (2) Optic pathway or hypothalamus glioma: Enlargement or/and elongation of the optic nerves and optic chiasms on STIR images; Masses in the region of the optic chiasm or hypothalamus with mixture high intensity on T2WI and FLAIR images. Significant and irregular enhancement was seen on SE T1WI. (3) Multiple neurofibromas in the spine: Multiple bulky tumours extending along the spinal nerves were shown on SE T2WI and STIR and STIR images with higher signals. Conclusion: MR is suitable for routine imaging investigation in diagnosis and follow-up of NF1. The MR imaging protocol for NF1 could show multiple abnormalities of NF1 better
[en] Two adult patients are described with multifocal osteolytic lesions radiologically simulating a vascular tumor. One patient had multiple bones involved. Histologically, the individual lesions had the features of the nidus of osteoid osteoma/osteoblastoma. A review of the English language medical literature yielded only one other reported case with similar features. The process is designated as osteoblastomatosis to indicate its bone-forming character, prominent osteoblast proliferation, and multiplicity. The cases are distinguished from multifocal/multicentric osteoid osteoma and osteoblastoma, and from benign and malignant vascular tumors. (orig.)
[en] Extraskeletal osteosarcoma is a rare bone-forming tumor. It accounts for 2 to 4% of all osteosarcomas and usually present later in life than osteosarcoma involving bone. The etiology is unknown, although its developments following trauma and in areas subjected to radiotherapy has been reported. When the lesion becomes calcified, its aspect is suggestive, although not pathognomonic, of this tumor. We present a case of extra skeletal osteosarcoma with the characteristic radiological findings and retroperitoneal location, which is one of the most common sites. The differential diagnosis is dicussed and the literature reviewed. (Author) 13 refs
[en] Vascular involvement in neurofibromatosis type 1 is rare but has the potential to be fatal. We report a case of a patient with spontaneous rupture of a left intercostal artery aneurysm, which presented as a massive left hemothorax and was successfully treated by transarterial coil embolization.