Glioblastoma with adipocyte-like tumor cell differentiation--histological and molecular features of a rare differentiation pattern.

We report on three adult patients with primary glioblastomas showing prominent adipocytic (lipomatous) differentiation, hence referred to as "glioblastomas with adipocyte-like tumor cell differentiation." Histologically, the tumors demonstrated typical features of glioblastoma but additionally contained areas consisting of glial fibrillary acidic protein (GFAP)-positive astrocytic tumor cells resembling adipocytes, that is, containing large intracellular lipid vacuoles. Comparative genomic hybridization (CGH) and focused molecular genetic analyses demonstrated gains of chromosomes 7, losses of chromosomes 9 and 10, as well as homozygous deletion of p14(ARF) in one of the tumors. The second tumor showed gains of chromosomes 3, 4, 8q and 12 as well as losses of chromosomes 10, 13, 15q, 19 and 22. In addition, this tumor carried homozygous deletions of CDKN2A and p14(ARF) as well as point mutations in the TP53 and PTEN genes. The third tumor also had a mutation in the PTEN gene. None of the tumors demonstrated EGFR, CDK4 or MDM2 amplification. Taken together, our results define a rare glioblastoma differentiation pattern and indicate that glioblastomas with adipocyte-like tumor cell differentiation share common molecular genetic features with other primary glioblastomas.

Recurrent spinal arachnoid cyst in a cat.

Spinal arachnoid cysts (SACs) are uncommon expanding lesions in the spinal canal. They are rarely diagnosed in dogs, and there are only four published cases in cats. We report a case of a 12-year-old cat with recurrent signs of intermittent urinary incontinence and hind limb ataxia 2 years after surgical marsupialisation of a spinal arachnoid cyst at T11/12. Recurrence of a cyst was diagnosed by myelography. Repeated marsupialisation after laminectomy was successful and the cat recovered satisfactorily although intensive physical therapy was necessary. SACs are very rare in cats and seem to occur mainly as a secondary lesion to spinal and meningeal trauma or irritation due to bony changes of the vertebrae.

"Juxtafacet cysts", a misleading name for cystic formations of mobile spine (CYFMOS).

To present 58 cystic space-occupying formations of the spinal canal in 53 cases; these formations are called "juxtafacet cysts". Fifty-Three patients (33 women and 20 men, with an average age of 60.8 years) were evaluated retrospectively by neurosurgery. All of the patients had received simple X-P, computed tomography (CT) and magnetic resonance imaging (MRI) before surgery. The neurological findings were evaluated on admission and in a follow-up review. Surgical intervention was performed on all patients and they underwent gross-total cyst removal. During surgery, the origin of a cyst was well observed. Follow-up data ranged from 6 to 46 months. Patient outcome was graded on a scale of excellent, good, or poor. Histological findings were evaluated. In 53 patients 58 cysts were identified. Four of the patients had multiple cysts. All cysts were associated with mobile spine. Fifty-five cysts were found in the lumbo-sacral region, two cysts were found in the cervico-thoracic region and one cyst in the thoracic region. Forty-two patients presented back pain and 52 patients presented radicular pain. Four patients had a cauda equina syndrome. Sensory disturbance was observed in 24 cases and motor weakness was observed in 21 cases. Claudication was observed in 19 cases. All cases with cervico-thoracic or thoracic cysts presented myelopathy. The duration of these clinical symptoms ranged from 10 days to 10 years. After surgery there was no case of a recurrent cyst during the follow-up period. Thirty-four cases had an excellent outcome, 18 a good outcome, and one a poor outcome. Out of 58 cysts 32 were joint cysts (11 synovial cysts, 21 ganglion cysts). A further 19 were flavum cysts, one was a posterior longitudinal ligament (PLL) cyst and six others were unknown pseudo cysts. In 34 of the cysts we found hemosiderin deposits and in eight amyloid deposits. Present investigation and findings in literature show a clear comparison of these cystic formations and the mobile part of the spine. An anatomical relation to a vertebral joint ("facet") is only found in some of the cases (32 of 58). Further to that, the name "cyst" is not correct either, because most of the cystic formations are presented without a cell lining on their internal wall and therefore they are pseudo-cystic. We think that these cystic formations should be called "cystic formations of mobile spine" (CYFMOS) rather than "juxtafacet cysts". A surgical intervention is the best treatment for these cysts if they cause a compression of nerve roots or/and of the spinal cord.

[Spinal and cerebral leptomeningeal seeding from a melanocytoma of the cerebello-pontine angle]. / Spinale und zerebrale Meningeosis eines sekundär malignisierten Melanozytoms des Kleinhirnbrückenwinkels.

Meningeal melanocytoma refers to the uncommon clinical appearance of a generally benign tumour deriving from leptomeningeal melanocytes. Meningeal spread of this tumour is very rarely observed. We present the case of a 38-year-old man with meningeal melanocytoma of the cerebello-pontine angle, who showed a biphasic course of this disease, with a stable period followed by a steady progress within few months. After surgical resection of the melancytoma in the left skull base and of a first local recurrence five years later, a second local recurrence occurred 6 years after diagnosis, with intracerebral and spinal meningeal seeding. This tumor did not respond to a combined radiochemotherapy including oral temozolomide, and the patient died 5 months after starting treatment for this relapse. Secondary malignisation of the melancytoma is suggested.

A new model of reversible sinus sagittalis superior thrombosis in the rat: magnetic resonance imaging changes.

OBJECTIVE: The causes of cerebral sinus and vein occlusion and the accompanying parenchymal changes remain largely unexplained. The clinical variability and low incidence of the disease complicate systematic clinical investigations. Animal studies are indispensable; however, existing animal models of sinus thrombosis do not allow for long-term follow-up studies and are not suitable for pharmacological recanalization because sinus thrombosis is induced by ligation and injection of thrombogenic substances and does not resemble sinus thrombosis in humans. METHODS: We induced thrombosis of the superior sagittal sinus (SSS) by careful topical application of ferric chloride onto the SSS of rats, leading to highly reproducible occlusions. Magnetic resonance imaging was performed immediately after initiation of thrombosis and on postoperative Days 1, 2, and 7. Diffusion- and T2-weighted images allowed for calculation of the apparent diffusion coefficient and T2 relaxation time. Vascular status was assessed by venous magnetic resonance angiography. Neurological deficits were assessed with the rotarod test. RESULTS: Seven days after induction of thrombosis, partial recanalization (50.7% of the SSS remaining occluded) was accompanied by a resolution of early generalized changes of the apparent diffusion coefficient and of T2 relaxation time, indicating edema of the entire brain parenchyma. Compared with sham-treated animals, clinical skills in the experimental group improved over time, which was statistically independent from the degree of recanalization. Histopathological analysis revealed no signs of cerebral infarction. CONCLUSION: This is the first animal model of SSS thrombosis that offers the possibility to investigate pathophysiological aspects of the disease as well as the influence of therapy on the nature of disease progression.

April 2004: woman in her early fifties with a cervical intraspinal and extraspinal mass lesion.

April 2004: A 53-year-old woman presented with a large club-shaped intra- and extraspinal tumor of the C6 nerve root which had intradurally grown through the enlarged C5-6 neural foramen and focally infiltrated the dura mater. Microscopy revealed a melanin-pigmented tumor with spindle-shaped and epithelioid cells and scattered psammoma bodies, a so-called psammomatous melanotic schwannoma (PMS). More than half of the patients with PMS have Carney complex, a genetically heterogeneous multiple neoplasia syndrome of autosomal-dominant inheritance, which in our patient, however, could not be detected unequivocally. Prognosis of all melanotic schwannomas (MSs) is not good with local recurrences or metastases in over 40% of cases. In our case, frequent versicular nuclei with distinct nucleoli, occasional mitoses and apoptoses and increased focal MIB-1 labeling indices prompted us to diagnose a malignant PMS. However, histologic criteria for malignancy in MSs are not clearly defined and there is no reliable histopathological indicator of malignant clinical behavior in MSs. Therefore, designation of "PMS with malignant histologic features" may be more appropriate. Since tumor recurrences and metastases im MSs may occur after more than 5 years, long-term follow-up of affected patients is required. One year after operation our patient showed no signs of tumor recurrence or metastases.

Mismatch repair protein hMSH2 in primary drug resistance in in vitro human malignant gliomas.

OBJECT: The mismatch repair (MMR) system has previously been implicated in acquired chemoresistance in malignant gliomas in humans. Its impact on the primary chemoresistance in glioblastoma multiforme (GBM) has not been determined in detail, however. METHODS: The authors investigated the expression of both the MMR genes (hMSH2, hMLH1, hPMS1, hPMS2, and hMSH6) at the transcriptional level through reverse transcription-polymerase chain reaction and the hMSH2 protein through Western blot and immunohistochemical analysis of tumor tissue and primary cell cultures of 25 in vitro human de novo GBMs without prior experimental treatment. Results of these analyses were compared with data on in vitro chemoresistance to nine drugs that are in general use in glioma therapy. All MMR genes were expressed in the GBMs, with no significant difference among the individual tumors except in one respect; that is, GBMs showed either relatively high levels or barely detectable levels of hMSH2 messenger (m)RNA and protein expression. All multiresistant tumors demonstrated high hMSH2 expression, and all but two of the sensitive tumors exhibited low hMSH2 mRNA levels. CONCLUSIONS: Analysis of the data indicates that functional alterations of the MMR system are involved in the primary drug resistance in in vitro human malignant gliomas. Analysis of hMSH2 expression might therefore predict therapeutic responses in humans with GBMs.