Quantitative Evaluation of Diffusion and Dynamic Contrast-Enhanced MR in Tumor Parenchyma and Peritumoral Area for Distinction of Brain Tumors.

PURPOSE: To quantitatively evaluate the diagnostic efficiency of parameters from diffusion and dynamic contrast-enhanced MR which based on tumor parenchyma (TP) and peritumoral (PT) area in classification of brain tumors. METHODS: 45 patients (male: 23, female: 22; mean age: 46 y) were prospectively recruited and they underwent conventional, DCE-MR and DWI examination. With each tumor, 10-15 regions of interest (ROIs) were manually placed on TP and PT area. ADC and permeability parameters (Ktrans, Ve, Kep and iAUC) were calculated and their diagnostic efficiency was assessed. RESULTS: In TP, all permeability parameters and ADC value could significantly discriminate Low- from High grade gliomas (HGG) (p<0.001); among theses parameters, Ve demonstrated the highest diagnostic power (iAUC: 0.79, cut-off point: 0.15); the most sensitive and specific index for gliomas grading were Ktrans (84%) and Kep (89%). While, in PT area, only Ktrans could help in gliomas grading (P = 0.009, cut-off point: 0.03 min-1). Moreover, in TP, mean Ve and iAUC of primary central nervous system lymphoma (PCNSL) and metastases were significantly higher than that in HGG (p<0.003). Further, in PT area, mean Ktrans (p≤0.004) could discriminate PCNSL from HGG and ADC (p≤0.003) could differentiate metastases with HGG. CONCLUSIONS: Quantitative ADC and permeability parameters from Diffusion and DCE-MR in TP and PT area, especially DCE-MR, can aid in gliomas grading and brain tumors discrimination. Their combined application is strongly recommended in the differential diagnosis of these tumor entities.

Malignant gangliocytic paraganglioma of the duodenum with distant metastases and a lethal course.

Gangliocytic paraganglioma (GP) is rare and has been regarded as benign in general with a good prognosis. We present a patient with duodenal GP showing a malignant and lethal clinical course. A 47-year-old male patient was found to have a duodenal tumor and enlarged regional lymph nodes. The patient initially underwent a pancreaticoduodenectomy to resect the tumor and involved lymph nodes completely. Histological and immunohistochemical analyses showed findings typical of GP. However, the distant metastatic lesions in the liver and pelvic cavity were rapidly observed after surgery. The patient underwent chemotherapy and radiotherapy, as well as a second surgery to partly remove the metastatic mass in the pelvic cavity. The histological examination revealed no significant difference in histological features between the primary duodenal tumor and the metastatic pelvic mass. However, the patient finally died of the tumor due to the recurrence of the residual pelvic lesion and increased liver mass. To our knowledge, this is the first report of lethal GP with multifocal metastases. Our case confirms that GP should be regarded as a malignant potential tumor with behavior code of "1", rather than a benign tumor of "0".

Intraspinal dural-based primary osteoblastoma with aneurysmal bone cyst-like change.

Osteoblastoma is a benign bone-forming neoplasm that occurs commonly in the posterior elements of the spine and the sacrum. However, so far there has been no report of intradural osteoblastoma described in the literature. We present a unique case of intraspinal dural-based osteoblastoma with aneurysmal bone cyst-like change without evidence of vertebral involvement. An 11-year-old Chinese girl presented with a 3-month history of gradually progressive back pain and a weakness of both lower limbs. Thoracic MRI revealed a well-demarcated subdural mass at the T5 level with heterogeneous enhancement. Histologically, the tumor was found to be attached to the dura and composed of numerous osteoid spicules and trabecular bone with diffusely scattered osteoclast-type, multinucleated giant cells. Ectactic blood vessels and blood-filled cystic spaces were also observed. A diagnosis of primary intraspinal dural-based osteoblastoma with aneurysmal bone cyst-like change was made. To our best knowledge, this is possibly the first case of primary osteoblastoma arising from meninges. Meningeal osteocartilaginous tumors are rare, with obscure histogenesis. The differential diagnosis of osteoblastoma in unusual locations is difficult and the confirmation of diagnosis should be cautiously made. Awareness of dural-based osteoblastoma and its histological features is important to avoid a diagnostic pitfall caused by histological similarities to other intra-craniospinal lesions with osteoid differentiation or bone formation.

Sporadic meningioangiomatosis-associated atypical meningioma mimicking parenchymal invasion of brain: a case report and review of the literature.

Meningioangiomatosis is a rare hamartomatous lesion or meningiovascular malformation in brain. In extremely rare condition, meningioma may occur together with meningioangiomatosis, and only 19 cases have been described in English literature until now. We now report a case of meningioangiomatosis-associated meningioma with atypical and clear cell variant. A 34-year-old man presented a 3-month history of progressive numbness and weakness of his left lower extremity. He had no stigmata of neurofibromatosis type 2. Magnetic resonance imaging (MRI) revealed multifocal lesions in the right frontoparietal lobe. The lesions were totally removed. Microscopically, parts of lesions were atypical and clear cell meningioma corresponding to WHO grade II. The adjacent brain parenchyma showed the histological features of meningioangiomatosis. Neoplastic cells in atypical meningioma area were immunoreactive to epithelial membrane antigen (EMA) with high MIB-1 index of up to 20%. However, the spindle cells in meningioangiomatosis area were negative for EMA with low MIB-1 index of up to 1%. The diagnosis of atypical meningioma associated with sporadic meningioangiomatosis was made. To our knowledge, this is the first case of a meningioangiomatosis-associated meningioma with atypical and clear cell variant component to be described. The patient had been followed-up for 11 months without adjuvant radiotherapy or chemotherapy. No tumor recurrence was found during this period. Meningioangiomatosis-associated meningioma is more likely to occur in younger patients and histologically to mimic parenchymal invasion of brain. We suggest that postoperative radiotherapy or chemotherapy should be given careful consideration to avoid over-treatment due to erroneously interpret as malignant meningioma.

The state of the art of fetal magnetic resonance imaging.

OBJECTIVE: To assess the state of the art of fetal magnetic resonance imaging (MRI) in China. DATA SOURCES: Both Chinese and English language literatures were searched in the databases of PUBMED (1998-2005) and CNKI (1998-2005), 41 published articles about fetal MRI were selected. RESULTS: Fetal MRI can serve as an adjunct tool for ultrasonography because of its excellent soft tissue contrast, high spatial resolution, multiplanar capabilities, large field of view and simultaneous visualization of fetal and maternal structures. Since the development of ultrafast MRI sequences provides faster scan time and avoids motion artifacts, it is widely applied in detecting normal or abnormal fetal development, including the central nervous system, thoracic region, abdomen and others. In China, experience in fetal MRI has been scanty, but the technique will be extensively used in the near future because of its multi-faceted advantages. CONCLUSIONS: Compared with ultrasonography, MRI as a complementary imaging for fetal screening is prospective in China or other parts of the world because of its multiple superiorities.