[MR imaging in the diagnosis of primary and secondary cerebral infections]. / Wertigkeit der MRT in der Diagnostik primärer und sekundärer zerebraler Infektionen.

Cerebral infections may develop into a life-threatening condition. Fast and correct diagnosis is crucial for a differentiated therapy and MRI imaging is widely accepted as the method of choice. Both specific MR sequences and imaging characteristics of major cerebral infections are addressed in this overview. Furthermore, limitations and pitfalls of the method are discussed.

Outcome after whole brain radiotherapy alone in intracranial leptomeningeal carcinomatosis from solid tumors.

BACKGROUND: The purpose of the present study was to investigate outcome after whole brain radiotherapy (WBRT) alone as a palliative treatment without concomitant chemotherapy for intracranial leptomeningeal carcinomatosis (LMC). PATIENTS AND METHODS: Overall survival and treatment response were retrospectively analyzed in 27 consecutive patients with LMC from breast and lung cancer. All patients had evidence of intracranial manifestations of LMC. Seven potential prognostic factors were evaluated. RESULTS: Median overall survival (OS) for the entire group was 8.1 weeks. OS rates after 6 and 12 months were 26% and 15%, respectively. Improvement of neurological deficits was observed in 3 patients. In 3 of 4 patients with follow-up MRI studies, a decreased size of contrast-enhanced lesions was observed. Prognostic factors for improved OS on univariate analysis were absence of cranial nerve dysfunction, Karnofsky Performance Score (KPS) > 60%, and time interval > 35 months between the initial diagnosis of malignant disease and development of LMC. On multivariate analysis, absence of cranial nerve dysfunction remained the only significant prognosticator for OS (median 3.7 vs. 19.4 weeks, p < 0.001). CONCLUSION: WBRT alone is an effective palliative treatment for patients unfit/unsuitable for chemotherapy and low performance status suffering from intracranial LMC. However, prognostic factors should be considered in order to identify patients who are likely to benefit from WBRT.

Cerebral low-grade lymphoma and light chain deposition disease: exceedingly high IgG levels in the cerebrospinal fluid as a diagnostic clue.

Herein, we report the case of a 72-year-old male with an exceedingly rare manifestation of a low-grade lymphoma in the brain associated with light chain deposition disease (LCDD). The patient presented with epileptic seizures. Magnetic resonance imaging (MRI) of the brain revealed multiple hyperintense lesions in the right parietal lobe that were suspicious of vasculitis, low-grade glioma, or neurosarcoidosis. In the cerebrospinal fluid (CSF), but not in the serum, highly elevated IgG was found. A stereotactic biopsy of one cerebral lesion was performed. Histopathology revealed a low grade lymphoplasmacytic B-cell lymphoma with light chain deposition disease (LCDD). Bone marrow biopsy and laboratory workup did not show any systemic involvement. LCDD exclusively affecting the brain is an exceedingly rare finding. It can be associated with low-grade B-cell lymphoma. This is the first report of LCDD exclusively affecting the brain in an elderly patient. Compared with the two younger patients previously reported, the course of the disease was of a slow-evolving nature. In constellations of highly elevated IgG in CSF and multiple white matter lesions, LCDD should be considered as underlying pathology.

Benign meningioma developing late lung metastases: case report and review of the literature.

Here we report the case of a 65-year-old female with a histologically benign parietal falcine meningioma who developed multiple lung metastases 15 years after tumor resection. The meningioma was initially incompletely resected due to invasion of the sagittal sinus. Since it was diagnosed as a benign meningothelial meningioma Grade I WHO, the residual tumor was followed with serial imaging without adjuvant treatment. The patient subsequently developed lung lesions later identified as metastases. The lung lesions were successfully removed surgically and histologically diagnosed as meningothelial meningioma Grade I WHO. A repeat brain MRI revealed the known residual meningioma with no signs of interval tumor growth, but did demonstrate occlusion of the sagittal sinus. In the further course, the residual meningioma was completely removed. A review of the literature revealed only 15 well-documented cases of benign meningiomas that metastasized in an interval of up to 12 years after primary tumor resection. This case illustrates that histologically benign meningiomas Grade I WHO with stable disease of the primary tumor have the potential to develop hematogenous metastases even after a long time interval.

Aryl hydrocarbon receptor inhibition downregulates the TGF-beta/Smad pathway in human glioblastoma cells.

The dioxin/aryl hydrocarbon receptor (AhR) is a transcription factor, which has been attributed a role in human cancerogenesis, cell cycle progression and transforming growth factor-beta (TGF-beta) signaling. As TGF-beta is an important mediator of the malignant phenotype of human gliomas, we studied AhR expression and function in glioma cells. AhR was not only expressed in glioma cells in vitro, but was also detected in human gliomas in vivo by immunohistochemistry, with a predominantly nuclear staining in glioblastomas. The AhR agonist, 3-methylcholanthrene, induced AhR nuclear translocation and upregulated mRNA levels of the AhR target gene, cytochrome P450 1A1 (CYP1A1). Conversely, pharmacological inhibition of AhR using the novel AhR antagonist, CH-223191, or AhR gene silencing using small interfering RNA showed that constitutive AhR activity positively controls TGF-beta1, TGF-beta2 and latent TGF-beta-binding protein-1 protein levels in malignant glioma cells. Moreover, antagonism of AhR reduced clonogenic survival and invasiveness of glioma cells. In contrast, AhR regulates TGF-beta signaling negatively in non-neoplastic astrocytes. Thus, the pathogenesis of glioma formation may involve altered AhR regulation of the TGF-beta/Smad pathway, and AhR may represent a promising target for the treatment of human malignant gliomas and other diseases associated with pathological TGF-beta activity.

Histological findings on fetal striatal grafts in a Huntington's disease patient early after transplantation.

Cell transplantation is a promising therapeutic approach that has the potential to replace damaged host striatal neurons and, thereby, slow down or even reverse clinical signs and symptoms during the otherwise fatal course of Huntington's disease (HD). Open-labeled clinical trials with fetal neural transplantation for HD have demonstrated long-term clinical benefits for HD patients. Here we report a postmortem analysis of an individual with HD 6 months after cell transplantation and demonstrate that cells derived from grafted fetal striatal tissue had developed into graft-derived neurons expressing dopamine-receptor related phosphoprotein (32 kDa) (DARPP-32), neuronal nuclear antigen (NeuN), calretinin and somatostatin. However, a fully mature phenotype, considered by the expression of developmental markers, is not reached by engrafted neurons and not all types of interneurons are being replaced at 6 months, which is the earliest time point human fetal tissue being implanted in a human brain became available for histological analysis. Host-derived tyrosine hydroxylase (TH) fibers had already heavily innervated the transplants and formed synaptic contacts with graft-derived DARPP-32 positive striatal neurons. In parallel, the transplants contained a considerable number of immature neuroepithelial cells (doublecortin+, Sox2+, Prox-1+, ss3-tubulin+) that exhibited a pronounced migration into the surrounding host striatal tissue and considerable mitotic activity. Graft-derived astrocytes could also be found. Interestingly, the immunological host response in the grafted area showed localized increase of immunocompetent host cells within perivascular spaces without deleterious effects on engrafted cells under continuous triple immunosuppressive medication. Thus this study provides for a better understanding of the developmental processes of grafted human fetal striatal neurons in HD and, in addition, has implications for stem cell-based transplantation approaches in the CNS.

Intracranial arachnoid cyst associated with traumatic intracystic hemorrhage and subdural haematoma.

BACKGROUND: Brain arachnoid cysts are fluid collections of developmental origin. They are commonly detected incidentally in patients imaged for unrelated symptoms. CASE DESCRIPTION: A 15-year-old healthy boy with a recent history of head trauma experienced headache that gradually worsened over the course of 10 days. He underwent CT and MRI brain scans which revealed the presence of subdural haematoma caused by the rupture of a middle cranial fossa arachnoid cyst. This was accompanied by intracystic haemorrhage. The subdural haematoma was removed, while communication of the cyst with the basal cisterns was also performed. The postoperative course of the patient was uneventful. CONCLUSIONS: The annual haemorrhage risk for the patients with middle cranial fossa cysts remains very low. However, when haemorrhage occurs, in most occasions it can be effectively managed only with haematoma evacuation.

Primary anaplastic ganglioglioma with a small-cell glioblastoma component.

Gangliogliomas usually present as benign tumors corresponding to World Health Organization (WHO) Grade I. Very rarely, gangliogliomas show histological features of malignancy and are then classified as anaplastic gangliogliomas of WHO Grade III or IV. In most cases, anaplastic gangliogliomas developed after radiation therapy or progression from a pre-existing low-grade ganglioglioma. Here, we report the case of a 77-year-old male patient who was operated on a primary ganglioglioma with a highly anaplastic glial component corresponding to a small-cell glioblastoma. To our knowledge, this is the first reported case of a primary anaplastic ganglioglioma with a small-cell glioblastoma component.

Late cytomegalovirus polyradiculopathy following haploidentical CD34+-selected hematopoietic stem cell transplantation.

A 55-year-old man with acute myeloid leukemia in second relapse presented 4 months after haploidentical CD34+-selected hematopoietic stem cell transplantation (HSCT) with symmetric, progressive neurological deficits of the lower extremities. Although there was no molecular evidence for drug resistance in the cerebral-spinal fluid, antiviral combination therapy failed to control the rapidly progressing CMV polyradiculopathy (PRP) and encephalitis, which were confirmed by autopsy studies. Late CMV PRP as an unusual manifestation of CMV disease should be kept in mind in patients with suggestive neurological symptoms after HSCT.