Differential Diagnosis Of Brain Tumors Research Articles

Application of magnetic resonance spectroscopy in the differentiation of high-grade brain neoplasm and inflammatory brain lesions

This study aims at evaluating the application of magnetic resonance spectroscopy (MRS) in the differential diagnosis of brain tumors and inflammatory brain lesions. The examinations of 81 individuals, who performed brain MRS and were retrospectively analyzed. The patients with ages between 10 and 80 years old, were divided into two groups. Group A consisted of 42 individuals with diagnoses of cerebral toxoplasmosis and Group B was formed of 39 individuals with diagnosis of glial neoplasms. On analyzing the ROC curve, the discriminatory boundary for the Cho/Cr ratio between inflammatory lesions and tumors was 1.97 and for the NAA/Cr ratio it was 1.12. RMS is an important method useful in the distinction of inflammatory brain lesions and high-degree tumors when the Cho/Cr ratio is greater than 1.97 and the NAA/Cr ratio is less than 1.12. And so this method is important in the planning of treatment and monitoring of the therapeutic efficiency.

Galectin‐3: A useful biomarker for differential diagnosis of brain tumors

Galectin-3 (gal-3) is a 31 kDa beta-galactoside-binding lectin that is immunohistochemically expressed in macrophages, lymphocytes, and endothelial cells, and also in some neoplastic cells. Gal-3's expression in and significance to brain tumors has not been fully addressed. Here, we investigated its immunohistochemical expression in 409 cases of surgically resected primary brain tumors, including various glioneuronal tumors, pituitary adenomas, meningiomas and Schwannomas, among others. In normal brain tissues, gal-3 was robustly expressed in normal astrocytes, endothelial cells and macrophages. It showed consistent and diffuse positivity in 100% of the pilocytic astrocytomas, pleomorphic xanthoastrocytomas (PXA), Schwannomas, meningiomas, capillary hemangioblastomas, as well as in ependymomas, but it was completely negative in the diffuse astrocytomas, anaplastic astrocytomas, both low- and high-grades of the oligodendrogliomas, central neurocytomas, and medulloblastomas. Definitely positive but heterogeneous expression was found in various tumors including subependymal giant cell astrocytomas (SEGA), classic glioblastoma multiforme, anaplastic oligoastrocytomas, CNS primitive neuroectodermal tumors (CNS PNETs), and hemangiopericytomas. Eighty percent of small cell glioblstomas were completely negative, but 20% showed heterogeneous positivity for gal-3. Focal positivity for gal-3 was also found in dysembryoplastic neuroepithelial tumors (DNTs) and gangliogliomas, in which the positive cells were the astrocytic component. On the basis of our immunohistochemical data in conjunction with previous reports, we therefore conclude that gal-3 is differentially expressed in various brain tumors, and thereby, is a helpful biomarker in making differential diagnoses, especially in cases where a morphological diagnosis is controversial.

Méningiome kystique. À propos d'un cas et revue de la littérature

Background Cystic meningioma is a rare variety of meningioma. It represents 1,6 to 10% of intracranial meningiomas, the authors report a case of intracranial cystic meningioma with a review of literature. Case report A 46-year-old female presented with left parietooccipital headache followed by right side hemiparesis. CT scan brain showed a left parietal tumor with double solid and cystic components thought to be glioma or metastasis preoperatively. At surgery the extraaxial solid and cystic lesion had a well defined capsule that could be easily separated from the perilesional cortical surface. The tumor was totally removed. The histological study showed a cystic meningioma. Conclusion Cystic meningioma is an uncommon tumor that should be considered in the differential diagnosis of brain tumors with a cystic component.

Is There a Role for Apparent Diffusion Coefficients in the Differential Diagnosis of Brain Tumors?

We determined the potential benefits of apparent diffusion coefficient (ADC) values of enhancing-nonenhancing solid portions, cystic-necrotic areas and surrounding edema in the differential diagnosis of brain tumors. Eighty-eight patients with brain tumors: 16 low-grade gliomas, 21 high-grade gliomas, 26 metastases and 25 meningiomas were imaged prospectively in a 1.5 Tesla magnetic resonance (MR) unit. Routine MR imaging and echo-planar diffusion-weighted imaging (DWI) with b values of 0 and 1000 mm(2)/s were performed. ADC values were obtained in different tumor parts and peritumoral edema. The ADCs of contrast-enhancing tumor regions were higher in high-grade gliomas than meningiomas (p<0.05). No significant differences were found in ADCs of contrast-enhancing regions comparing other tumor groups (p≥0.05). The ADCs in non-enhancing tumor regions did not differ between low-grade and high-grade gliomas (p≥0.05). The ADCs in cystic-necrotic regions of tumors and surrounding edema were not significantly different comparing all tumor groups (p≥0.05). There were no significant differences between ADCs of contrast-enhancing and non-enhancing regions of high-grade and low-grade gliomas (p≥0.05). No significant differences were found in ADCs of contrast-enhancing and non-enhancing areas of tumors comparing to surrounding edema (p≥0.05). ADC was not found to be useful in distinguishing different tumor types and its value in the diagnosis of brain tumors is limited due to considerable overlaps.

Neuroradiological findings in atypical teratoid/rhabdoid tumor of the central nervous system

To evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) findings of atypical teratoid tumor/rhabdoid tumor (AT/RT) of the central nervous system (CNS). Twenty cases of CNS AT/RT have been found over the past 23 years in our hospital; these involving 11 boys and 9 girls whose mean age at diagnosis was 5.5 years. Their clinical data, the CT, and MRI findings were reviewed retrospectively. AT/RT was located in the cerebellum in 15 cases. Four cases arose from the supratentorial region, while only one occurred primarily in the lumbar spinal cord. Almost all cases revealed heterogeneous intensity and heterogeneous enhancement. Peripheral cystic components were common. Survival time ranged from 2 months to 3 years, with a mean survival of 11.6 months. Most cases of AT/RT are located in the cerebellum. The radiologic manifestations are non-specific. The diagnosis mainly depends on the pathologic findings. However, AT/RT should still remain in the differential diagnosis of brain tumors in young children, especially those located in the cerebellar hemisphere and with eccentric cysts.

Dynamic MRI using a field echo for brain tumors

Thirty-seven patients with brain tumors were studied by dynamic magnetic resonance imaging (MRI) using a field echo method. The tumors included nine pituitary adenomas, nine schwannomas, eight meningiomas, three gangliogliomas, two metastatic brain tumors, two malignant lymphomas and four other brain tumors, which were histologically diagnosed. Sequential images were acquired every 15 s for 5 min after administration of Gd-DTPA. With setting of a region of interest (ROI) in the tumors, the signal intensity (S.I.) ratios were calculated. The time intensity curves of the S.I. ratios were investigated. The dynamic curves of the S.I. ratio could be classified into four patterns: (1) rapid increase followed by gradual decrease (pituitary adenoma, meningioma and germinoma); (2) gradual increase followed by plateau (schwannoma); (3) rapid increase followed by gradual increase (metastatic brain tumor, malignant lymphoma and ganglioglioma); (4) no or faint enhancement (craniopharyngioma, epidermoid and cavernous angioma). Our study indicated that the tumors had the characteristic patterns of the dynamic curve of S.I. ratios. Dynamic MRI using a field echo provides useful information for the differential diagnosis of brain tumors.

Magnetization transfer imaging diagnosis of intracranial tuberculomas.

Tuberculomas (TB) can mimic brain tumors and abscesses. We performed prospective magnetization transfer ratio (MTR) analysis on 60 patients with 52 intracranial TB, 13 pyogenic abscesses and 65 tumors to determine the efficacy of magnetization transfer (MT) imaging in the differential diagnosis of brain tumors and infection. The nonenhancing cores of TB had significantly higher (P=.026) MTR (0.14+/-0.29) than necrotic components of high-grade gliomas (-0.19+/-0.22). The MTR of cores of TB were also higher than those of the cystic areas of low-grade gliomas (-0.53+/-0.32), benign (-0.09+/-0.21) and malignant (-0.07+/-0.25) tumors, and abscesses (-0.03+/-0.13), but the differences were not significant because of the small number of tumors and abscesses. There was also no significant difference between the MTR of abscesses, malignant and benign tumors. Using the criteria of MTR of necrotic center > 0.14 (mean MTR of TB) for diagnosing TB, MTR <-0.03 (mean MTR of abscesses) for diagnosing tumors and MTR between these values for diagnosing abscesses, MTI had diagnostic sensitivity of 68.42%, specificity of 80.49%, and accuracy of 76.67%. The improved diagnostic accuracy of MRI with the addition of MTR analysis from 86.67% to 91.67% and from 85.71% to 87.50% for both radiologists respectively was not significant. MTR analysis helped us to differentiate solitary TB or abscess from low-grade glioma in five patients and to diagnose multiple TB, abscesses, and metastases in four.

Diffusion-weighted echo-planar MR imaging in differential diagnosis of brain tumors and tumor-like conditions.

We assess diffusion-weighted MR images in the differential diagnosis of intracranial brain tumors and tumor-like conditions. Heavily diffusion-weighted (b = 1100 or 1200 s/mm2) axial images were obtained with single-shot echo-planar technique in 93 patients with pathologically confirmed various intracranial tumors and tumor-like conditions with diffusion gradient perpendicular to the images. We compared signal intensity of the lesions with those of gray and white matter, and cerebrospinal fluid (CSF). In 29 cases (31.1%) the lesions were isointense to gray and/or white matter. However, 5 cases (5.4%) showed extremely increased signal intensity: two epidermoid cysts; two chordomas; and one brain abscess. The entire portion of a tumor was markedly hyperintense in 10 cases (10.8%): four malignant lymphomas; four medulloblastomas; one germinoma; and one pineoblastoma. A CSF-like hypointense signal was seen in many cystic tumors, and cystic or necrotic portions of tumors. A neurosarcoid granulation was the only solid lesion showing characteristically a hypointense signal like CSF. The combination of markedly hyperintense and hypointense signals was seen generally in hemorrhagic tumors. Diffusion-weighted echo-planar MR imaging is useful in the differential diagnosis of brain tumors and tumor-like conditions, and suggests specific histological diagnosis in some cases.

201Tl SPET in the differential diagnosis of brain tumours.

The aims of this study were to assess the utility of 201Tl single photon emission tomography (SPET) in the differential diagnosis of brain tumours and to elucidate the relationship between 201Tl tumour uptake and degree of contrast-enhancement on magnetic resonance imaging (MRI). Early (15 min) and delayed (3 h) 201Tl SPET imaging and T1-weighted MRI were performed before and after Gd-DTPA enhancement in 101 (41 malignant and 60 benign) untreated brain tumours. The 201Tl uptake ratio (tumour-to-normal brain count ratio) for both the early and delayed SPET studies and the retention index (the ratio of delayed to early 201Tl uptake) were calculated. Malignant tumours were separated from benign tumours with 87% accuracy based on the assumption that tumours with a 201Tl retention index < 0.7 or no abnormal uptake are benign. Meningiomas and pituitary adenomas were differentiated from other benign tumours by their characteristic pattern on SPET. The degree of contrast-enhancement of the tumour on MRI was concordant with the early 201Tl uptake ratio for most histological types. However, schwannomas and cavernous haemangiomas showed a low 201Tl uptake ratio in spite of a high degree of contrast-enhancement on MRI. In conclusion, 201Tl SPET provides additional information that helps in the differential diagnosis of brain tumours.

Diagnostic assessment of brain tumours and non-neoplastic brain disorders in vivo using proton nuclear magnetic resonance spectroscopy and artificial neural networks.

Experiments were carried out to assess the potential of artificial neural network (ANN) analysis in the differential diagnosis of brain tumours (low- and high-grade gliomas) from non-neoplastic focal brain lesions (tuberculomas and abscesses), using proton magnetic resonance spectroscopy (1H MRS) as input data. Single-voxel stimulated echo acquisition mode (STEAM) (echo time of 20 ms) spectra were acquired from 138 subjects including 15 with low-grade gliomas, 47 with high-grade gliomas, 18 with tuberculomas, 18 with abscesses and 40 healthy controls. Two neural networks were constructed using the spectral points from 0.6 to 3.4 parts per million. In the first network construction, the ANN had to differentiate between tumours from infections, while the second network had to differentiate between all five histological classes. ANN analysis gave a histologically correct diagnosis for low- and high-grade gliomas with an accuracy of 73% and 98% respectively. None of the 62 tumours was diagnosed as an infectious lesion. Among the non-neoplastic lesions, ANN classification was correct in 89% of tuberculomas and in 83% of brain abscesses. The specificity of ANN diagnosis was 98%, 92%, 99%, and 100% for low-grade gliomas, high-grade gliomas, tuberculomas and abscesses respectively. The present data show the clinical utility of non-invasive 1H MRS by automated ANN analysis in the diagnosis of tumour and non-tumour cerebral disorders.

Tenascin in cerebrospinal fluid is a useful biomarker for the diagnosis of brain tumour.

Tenascin, an extracellular matrix glycoprotein, has been reported to be expressed predominantly on glioma tissue in the CNS, both in a cell associated and an excreted form. Recently, a highly sensitive sandwich type enzyme immunoassay for quantitative determination of tenascin was developed. In the present study, the amount of tenascin in CSF was measured. An increase of tenascin in CSF (> 100 ng/ml) was found in patients with an astrocytic tumour. The concentration was significantly higher (> 300 ng/ml) in high grade astrocytoma (anaplastic astrocytoma and glioblastoma) and a further increase (> 1000 ng/ml) was found in cases of CSF dissemination of high grade astrocytoma. On the other hand, tenascin concentrations were less than 100 ng/ml in non-astrocytic tumours and non-neoplastic neurological diseases, except meningeal dissemination of tumour cells, meningeal stimulation by infection, and subarachnoid haemorrhage. In cases of treated astrocytomas in remission, tenascin was negligible (< 100 ng/ml) in the CSF. The measurement of tenascin in CSF is useful for differential diagnosis of brain tumours and monitoring of astrocytic tumours.

Sensitivity and specificity of thallium-201 single-photon emission tomography in the functional detection and differential diagnosis of brain tumours.

The aim of this retrospective study was to assess the contribution of thallium-201 single-photon emission tomography (SPET) in the detection and differential diagnosis of brain tumours. In 90 patients 201Tl SPET was performed because of clinical or radiological suspicion of tumoral invasion, completed by technetium-99m hexamethylpropylene amine oxime and 99mTc-sestamibi SPET in some patients. For all tumours, diagnosis was based on biopsy or autopsy. Other diagnoses were made only after clinical and radiological follow-up for at least 6 months. Histologically tumours consisted of astrocytoma stage I or II (number of patients, n = 6), astrocytoma stage III (n = 8), glioblastoma multiforme (n = 14) and oligodendroglioma (n = 3), brain metastasis (n = 14), lymphoma (n = 3), meningioma (n = 3), pituitary adenoma (n = 2), pineal tumour (n = 1), colloid cyst (n = 1) and craniopharyngioma (n = 1). False-negative studies included pineal tumour (n = 1), colloid cyst (n = 1), craniopharyngioma (n = 1), astrocytomas stage I or II (n = 6) and stage III (n = 3), oligodendroglioma (n = 2) and metastasis in the brain stem (n = 1). Additional metastases approximately < 1.5 cm were not detected in two patients and 201Tl SPET underestimated tumoral extent in one patient suffering from glioblastoma multiforme (n = 1). A false-positive study was obtained in a patient with skull metastasis (n = 1). All 15 patients who were finally shown to suffer from ischaemic infarction had a normal SPET study 9-28 days after the onset of symptomatology. Of five patients with haemorrhagic infarction, studied within 2 weeks, four were false-positive. Of six patients with intracranial haemorrhage, studied 9-39 days later, one showed focal 201Tl accumulation. Two further false-positive studies consisted of angioma and epidural haematoma. Finally, SPET studies were normal in six patients with definite diagnosis of (reactive) gliosis (n = 3), Binswanger's encephalopathy (n = 1), postinfectious encephalopathy (n = 1) and multiple sclerosis (n = 1). In the patient population presented, sensitivity of 201Tl SPET for supratentorial brain tumours was 71.7% and specificity was 80.9%. Clinical information and control SPET studies in combination with early, 30-min and 3- to 4-h delayed imaging may be expected to improve on these figures. On the other hand it seems that, in addition to tumoral histology, the presence of tumours in the fossa posterior and small volumes contribute to the occurrence of false-negative 201Tl SPET studies.

Homonymous hemianopsia in brain tumors

Homonymous hemianopsia may be caused by tumors in the region of the optic tract, the lateral geniculate body, the optic radiation, and the visual cortex. Tumors are responsible for about two-thirds of the temporal lesions and about one-half to one-third of the parietal and occipital lesions. With brain tumors a chronological sequence of two groups of signs and symptoms is the rule: first the focal symptoms corresponding to the tumor lesion in a defined cerebral area, later the distant effects of the increasing volume of the tumor, which lead to the general signs of increased intracranial pressure. The different types of homonymous hemianopia in tumor lesions along the suprachiasmatic pathway (optic tract, lateral geniculate body, temporal lobe, parietal lobe, occipital lobe) are described and discussed. The general neurological signs and symptoms are briefly reviewed. Demonstration of important cerebral diagnostic examination methods (plain X-ray, electroencephalogram, computer tomogram, nuclear magnetic resonance, angiography). Differential diagnosis of brain tumors (hematomas, abscesses, granulomas, parasites etc.).

Dynamics of contrast enhancement in delayed computed tomography of brain tumors--tissue-blood ratio and differential diagnosis of brain tumors (author's transl)

Thirty-one patients with brain tumor were studied by CT delayed scan performed 60 and 120 minutes after intravenous administration of contrast medium. Dynamics of contrast enhancement (CE) in the lesion were analyzed quantitatively and qualitatively by calculating the tissue-blood ratio (TBR) at each scan. Since the individual blood contrast medium concentration had a wide range of values in spite of a settled dose given by body weight, it was necessary to calculate the TBR to analyze the intensity of CE qualitatively. Dynamics of CE are shown as relative TBR (R-TBR) which represents the ratio of TBR 60 minutes (TBR1) and 120 minutes (TBR2) after intravenous administration of contrast medium to the initial TBR (TBR0). The higher R-TBR means the higher retention of contrast medium in the tumors. R-TBR2 (TBR2/TBR0) was found to be very useful for differential diagnosis of brain tumors. The R-TBR2 could be classified into three types : less than 1.5 (type 1); 1.5 to 3.0 (type II) ; and more than 3.0 (type III). In the glioma group, 7 of 8 astrocytomas, grade 3 and 4, were type III ; and all of 3 astrocytomas grade 2, were type II . All of 7 meningiomas were type I. In 5 pituitary adenomas, 4 were type II and 1 was type I. In 4 neurinomas, 3 were type III, and 1 was type II . In 4 metastatic tumors, 2 were type II, and 2 were type III. By this method meningioma, pituitary adenoma and neurinoma may be differentiated from each other. We can also presume the degree of malignancy and its distribution in glioma. The possibility of differential tumor diagnosis and mechanism about various types of dynamics of CE are discussed.

PSYCHIATRIC PICTURE IN PONTINE TUMORS

Cushing (1927) first drew attention to the possibility of intracranial tumors in children. Bailey. et aI. (1939) also have laid stress upon their occurrence. Ford (1955) stated that a result of the slow growth of most brain tumors. the onset is usually insidious and the course slowly progressive. The usual symptoms of headache. vomiting. diplopia. reduction of vision. vertigo and unsteadiness of gait. and in most cases focal symptoms. are typical. and the diagnosis is usually made if it is thought of at all. Although a mention is made of behavior disorders as being a part of the differential diagnosis of brain tumors. reports of predominantly psychological symptomatology are not common. Tumors of the fourth ventricle are notoriously difficult to diagnose; they may manifest the clinical picture of encephalitis or gastrointestinal disease and present symptoms of neurological note only late in the course of the disease. In a recent year. we have seen two male children under four years of age who presented the symptoms of vomiting and anorexia which seemed directly related to psychological problems. These children were referred to us by pediatricians because of the