Expression and significance of vascular permeability factor in tumour infiltrating lymphocytes of brain metastases

Correlation Analysis between Retention of Gd-DTPA in the Cystic Area of Brain Metastasis and MRI Signs

Objective

The aim of this study is to investigate gadolinium-diethylenetriaminepentacetate (Gd-DTPA) retention in the cystic area of brain metastasis and its correlation with MRI signs.

Methods

Clinical and MRI data of 76 patients with brain metastasis in the cystic area were collected. The contrast signal intensity (CSI) of the cystic area and edema area in the plain scan, enhanced scan, and plain scan after enhancement within 1 month (hereafter referred to as “enhanced plain scan”) were analyzed to determine whether Gd-DTPA was retained in these areas. The lesions with higher CSI values on the enhanced plain scan were classified as the Gd-DTPA retention group and the remaining lesions as the Gd-DTPA-free group. The two groups were compared to determine significant differences in primary lesion type, tumor size, tumor location, capsule wall thickness and morphology, peritumoral edema, and renal function.

Results

A total of 123 lesions were detected. The CSI of the enhanced plain scan exceeded that of the plain scan and enhanced scan in the cystic area (P < 0.05). There were 54 lesions (43.9%) with Gd-DTPA retention in the cystic area and 69 lesions (56.1%) without Gd-DTPA retention. Significant differences were observed in tumor size and cystic wall thickness between the two groups (P < 0.05), while no significant differences in primary lesion type, cystic wall shape, peritumoral edema, or function were observed.

Conclusion

The retention of Gd-DTPA was found in the cystic area of some brain metastases, which was correlated with tumor size and cystic wall thickness.

The value of DTI: achieving high diagnostic performance for brain metastasis

BACKGROUND

The evaluation of brain metastases generally requires post-contrast MRI exam, but some patients have contraindication to contrast medium administration.

PURPOSE

To investigate the value of the MRI diffusion tensor imaging (DTI) for detection of metastatic brain tumor.

MATERIALS AND METHODS

We retrospectively analyzed the MRI data from 23 patients (13 males and 10 females) with brain metastases. The MRI protocol consisted in T1WI, T2WI, post-contrast 3DT1WI and DTI images (b = 1000) sequences. The brain metastatic lesions were counted in each of these sequences. We compared the advantages and limitations of different sequences in the brain metastases detection. The number of metastatic lesions identified on the contrast-enhanced 3DT1WI image is used as the reference. FA values were measured in the intratumoral, adjacent peritumoral and distant peritumoral edema area (PTEA) of brain metastasis, and the differences were statistically analyzed.

RESULTS

DTI can detect more brain metastatic lesions rather than T1WI and T2WI. The number of brain metastases on DTI is similar to post-contrast 3D T1WI. There is no statistical difference in the FA value change between the adjacent and distant PTEA.

CONCLUSION

The DTI original image can be used as an alternative examination for patients with contraindications to contrast-enhanced MRI. It has high sensitivity to intratumoral hemorrhage, which has advantage to detect brain metastatic lesions as compared with T1WI or T2WI images.

Cerebellar swelling after surgery for medulloblastoma with leptomeningeal dissemination in children. A case based-update

OBJECT

Despite the improvement in the overall management of medulloblastomas in recent years, certain phenomena and in particular postoperative cerebellar swelling remain an enigma. This rare complication, little described in the literature, is nonetheless life threatening for the patients.

CASE REPORTS

We report our experience about two children who developed severe cerebellar swelling with hydrocephalus and upward herniation soon after a gross total resection of a fourth ventricle medulloblastoma by a telo-velar approach. Despite rapid management of ventricular dilation and optimal medical intensive treatment of intracranial hypertension, both children died quickly after the surgery. Pathological examination analyses were in favour of anaplastic/large cell medulloblastoma.

DISCUSSION

Diffuse cerebellar swelling with upward herniation may occur postoperatively in young children with anaplastic/large cell medulloblastoma with leptomeningeal spread. In the literature, only 4 cases have been so far described with delayed onset of symptoms. Two children survived with an aggressive management (decompressive surgery and early radio-chemotherapy).

CONCLUSION

Cerebellar swelling is an unrecognised and sudden complication of posterior fossa surgery for metastatic anaplastic medulloblastoma with leptomeningeal dissemination in young children. An initial less invasive surgical approach could be considered in such cases, in order to prevent this complication with potentially tragic issue, and which cannot be managed with a CSF shunt alone.

Delayed diffuse cerebellar swelling after resection of medulloblastoma: case report and review of literature

INTRODUCTION

Delayed diffuse cerebellar swelling is a rare life-threatening complication following medulloblastoma resection.

PRESENTATION

We present our experience of managing a 4-year-old who developed diffuse cerebellar swelling with upward herniation 41 days after resection of a large cell anaplastic medulloblastoma.

CONCLUSION

Emergency chemotherapy alone was sufficient in promoting regression of swelling and recovery from coma. Reports of similar cases are scant. Chemotherapy may be a critical component of treatment.

Reenlargement of radiation necrosis after stereotactic radiotherapy for brain metastasis from lung cancer during bevacizumab treatment

We describe a 55-year-old man who received stereotactic radiotherapy (SRT) for the treatment of brain metastasis from lung adenocarcinoma. Fourteen months after SRT, right-sided hemiparesis developed, and magnetic resonance imaging revealed progression of perifocal edema and an enhanced lesion. Cerebral radiation necrosis was diagnosed, and treatment with bevacizumab was initiated. The lesion clearly responded to bevacizumab therapy, but reenlarged 8 months later and was surgically resected. Histopathological analysis of the resected specimen revealed large areas of necrosis; however, viable tumor cells were detected in the necrotic areas. Reenlargement of the necrotic lesion was attributed to the recurrence of lung cancer.

Pattern analysis accounts for heterogeneity observed in MRI studies of tumor angiogenesis

MRI is a method of choice for assessing anatomical structures or angiogenesis-related parameters noninvasively during tumor progression. Typically, tumor tissue displays a high degree of heterogeneity that can be evaluated using pattern analysis (PA), which comprises shape and texture analysis. This work aims at implementing PA methods to study angiogenesis in a murine tumor model and testing its sensitivity with regard to detecting changes elicited by administration of a drug. Twelve balb/c-nude mice were injected subcutaneously with 10(6) C51 cells (colon carcinoma). A first group (N = 6) of animals was treated with dimethyloxalylglycine, a drug known to stabilize hypoxia-inducible-factor-α, which among other functions, is involved in angiogenesis. The second group (N = 6) was treated with saline. MRI experiments assessing tumor blood volume and permeability-maps (K(trans) ) were performed immediately before and 6 days after drug treatment. Data have been analyzed using standard histogram analysis and PA. Standard histogram analysis did not reveal any difference between the two groups, neither before nor after the treatment. In contrast, PA revealed significant differences between drug and placebo treated mice in the texture of the TBV and K(trans) maps after drug treatment, but not with regard to tumors shapes. The results indicated that in view of the heterogeneity of tumor tissue, standard histogram analysis appears insensitive in picking-up differences in response to treatment, while PA appears to be particularly sensitive to changes in texture.

Very early expression of vascular endothelial growth factor in brain oedema tissue associated with brain contusion

BACKGROUND

Brain oedema associated with cerebral contusion can be life-threatening. Mechanisms of the development of brain oedema are still unclear.

METHOD

We investigated the expression of vascular endothelial growth factor (VEGF) and its receptor VEGFR-2 (KDR/Flk-1) in the contusional brain tissue obtained during neurosurgery from 5 patients.

FINDINGS

VEGF is expressed in some but not all the astrocytes, and KDR/Flk-1 is expressed in vascular endothelial cells in the con-tusional tissue as early as 3 hours after onset.

CONCLUSION

The results suggested that the VEGF is induced in the contusional tissue in the very early period after onset, and that it increases capillary permeability via KDR/Flk-1 resulting in vasogenic type brain oedema.