Intratumoral Cysts Research Articles

Pituitary Adenoma with Cholesterol Clefts.

Histologically, cholesterol clefts are often observed in craniopharyngioma, Rathke's cleft cyst, and various granulomas. However, pituitary adenomas with cholesterol clefts are rare. A 46-year-old woman developed visual field disturbance. She had no history of severe headache that would suggest pituitary apoplexy. She presented with homonymous bitemporal hemianopsia and galactorrhea. Blood prolactin level was 63.1 ng/mL Other hypophysial hormone levels were within normal range. Magnetic resonance imaging revealed a pituitary tumor with intratumoral cyst. The cyst showed high intensity on T1- and T2-weighted images. The tumor was demonstrated with iso intensity on T1-weighted image and with high intensity on 12-weighted image. She underwent trans-sphenoidal surgery. The tumor was soft, with yellowish, oily fluid, probably the cyst content. By light microscopy with hematoxylin and eosin staining, a typical chromophobic adenoma of the pituitary was identified. Immunostaining revealed immunoreactivity for ACTH in several cells. Many cholesterol clefts and several hemosiderin pigment containing macrophages were observed. Electron microscopy demonstrated a pituitary adenoma with sparse and small secretory granules and numerous lysosomes. The cyst was most likely caused by focal hemorrhagic infarction, followed by the formation of cholesterol crystals, the appearance of hemosiderin containing macrophages, foreign body product cells, and accumulation of lysosomes.

Tenascin-C expression in the cyst wall and fluid of human brain tumors correlates with angiogenesis.

Tenascin-C (TN) is an extracellular matrix glycoprotein with a characteristic six-armed structure. The aim of this study was to determine whether the concentration of TN in the cyst fluid of brain tumors can be used as a marker for angiogenesis and glioma grade. We investigated the expression of TN in the cyst wall and cyst fluid of human brain tumors by immunohistochemistry, immunoprecipitation, and immunoblotting. The tumors included 12 astrocytomas (5 glioblastoma multiforme tumors, 1 anaplastic astrocytoma, 1 low-grade astrocytoma, 4 juvenile pilocytic astrocytomas, and 1 mixed glioma), 2 dysembryoplastic neuroepithelial tumors, 3 craniopharyngiomas, 2 ependymomas, 2 metastatic carcinomas, 3 arachnoid cysts, 1 glial ependymal cyst, and 1 inflammatory cyst. We detected no expression of TN in the cyst fluids of the ependymomas, craniopharyngiomas, and nonpilocytic low-grade astrocytoma. By contrast, TN was detected in the cyst fluids of all the other tumors. Results of quantitative immunoblotting using a PhosphorImager unit (Molecular Dynamics, Sunnyvale, CA) revealed that, on average, a 5-fold higher signal was observed in the glioblastoma multiforme tumors as compared with the anaplastic astrocytoma, and a 10-fold higher signal as compared with the mixed glioma, juvenile pilocytic astrocytomas, and dysembryoplastic neuroepithelial tumors. Results of TN immunohistochemistry in the astrocytomas correlated with glioma grade, with stronger staining of the hyperplastic vessels and tumor cells being observed in higher grade gliomas. No TN immunoreactivity was detected in the walls of the ependymomas, arachnoid cysts, and glial ependymal cyst that lack hyperplastic vessels, and minimal TN immunoreactivity was observed in the perivascular gliotic rim of the craniopharyngiomas. No TN was detected in the cyst fluid of these cystic processes. The presence of TN in and around the hyperplastic vessels and tumor cells present in the cyst walls of astrocytomas and its deposition in the intratumoral cyst fluid in which angiogenic factors have been detected further suggests a role for TN as an angiogenic modulator. These preliminary results suggest that immunodetection of TN in the tumor cyst fluid may indicate tumor type and grade.

Cystic meningiomas resembling glial tumors

Meningiomas can be associated with peripheral or intratumoral cysts. Meningiomas with intratumoral cysts, also called "true cystic" meningiomas, are rare and can frequently be confused with glial or metastatic tumors. We report three cases of "true cystic" meningiomas and discuss the preoperative evaluation, etiology, and surgical treatment of these cystic lesions with reference to the literature. Magnetic resonance imaging (MRI) and computed tomography (CT) studies usually display a cystic lesion close to the dura with or without enhancement of the cyst wall. Multiplanar MRI scans are very useful to show the presence of a solid tumor or some dural enhancement. Some cases of "true cystic" meningiomas however, are still erroneously preoperatively diagnosed. Complete surgical removal of the tumors and of the entire cyst wall was performed in our cases. Despite the absence of a typical ring enhancement of the cystic lesion in two cases, histopathologic studies displayed the presence of tumor cells on the cyst wall of both cases. Tumor cells can be present on the cyst wall and therefore can be one of the causes of tumor recurrence if not totally removed. Accurate preoperative radiologic diagnosis (multiplanar MR images) and intraoperative histopathologic studies are fundamental in that they will definitely influence the surgical strategy and outcome.

Cystic meningioma

Meningiomas are usually solid tumours. Cystic changes in meningiomas are rare. These cysts may occur extratumoural, peritumoural or intratumoural. Diagnostic difficulties arise in cases of cystic meningiomas. Nine cases of cystic meningiomas were operated on in the past 6 years at the department of neurosurgery University of Alexandra. The mean age of patients was 46.2 years. Male to female ratio was 1/2. Less oedema was observed in extratumoural cysts, and more oedema in intratumoural cysts. The fluid contained was dark brown or dirty yellow in intratumoural cysts (type C), xanthochromic in peritumoural cysts surrounded by tumour tissue (Type B), or clear fluid in extratumoural cysts (Type A). Based on these two observations it is proposed that the cyst fluid and peritumoral oedema may represent variable degrees of degeneration or secretion by tumour cells. Pre-operatively diagnostic criteria are presented.

Angiomyolipoma and renal cell carcinoma: US differentiation.

To analyze whether shadowing and other ultrasound (US) features were helpful for distinguishing angiomyolipoma (AML) from renal cell carcinoma (RCC). US images were reviewed of 49 patients with RCC and 35 patients with AML. Each tumor was evaluated for size, location, echogenicity, homogeneity, shadowing, hypoechoic rim, and intratumoral cysts. When available, computed tomographic (CT) scans of AMLs were analyzed for the amount of fat and soft tissue in each lesion. AMLs tended to be smaller and more frequently echogenic than RCCs, but statistically significant overlap occurred. Shadowing was seen in 12 (33%) AMLs but was not seen in RCCs. Hypoechoic rims and intratumoral cysts were seen only in RCCs (numbers were too small to perform further statistical analysis). In hyperechoic renal masses, the presence of shadowing, a hypoechoic rim, and intratumoral cysts are important findings that may help distinguish AML from RCC.

Cystic meningiomas

BACKGROUND Meningiomas are generally solid tumors and are easily diagnosed by CT scans and MRI scans. Rarely are these tumors associated with cysts that can cause a confusion in the pre- and intraoperative diagnosis. Cysts associated with meningiomas may be intratumoral or peritumoral. METHODS The authors conducted a retrospective study of the seventeen meningiomas, out of a total number of 232, which were associated with cysts. The cysts were classified based on their relationship to the tumor. The patients' sex, age group, location of the tumor, and pathological type of tumor were also analyzed. RESULTS The 17 cases of cystic meningioma formed 7.3% of the meningiomas seen between 1984 and 1993. Eleven of these were intratumoral and 6 peritumoral. One case had both intra- and peritumoral cysts. The tumors were found mostly in the fourth and fifth decades of life. Histologically, all the peritumoral cysts except one were associated with meningotheliomatous meningiomas. Tumors with peritumoral cysts were more common in males. Intratumoral cysts, more common in females, were angioblastic or meningotheliomatous on histopathology. Only one case was an anaplastic meningioma. CONCLUSION Cysts associated with meningiomas, although uncommon, are certainly not rare. The peritumoral and the intratumoral cysts form distinct subtypes needing separate consideration. Cystic meningiomas are only rarely malignant.

Neuroepithelial Tumors of the Brain Stem

Summary: We review 86 brain stem tumors that are classified into three groups according to strict pathological criteria [World Health Organization (WHO) classification] to give the elements of diagnosis and prognosis. Group I gathers 39 cases of benign tumors, usually WHO grade I pilocytic astrocytoma, involving the cervicomedullary junction, the medulla oblongata, the mesencephalon, or the 4th ventricle (with dorsal exophytosis). The duration of symptoms before diagnosis is usually >6 months. Magnetic resonance imaging (MRI) scan shows well-delimited lesions with hyposignal in Tl-weighted sequences, with signal enhancement after gadolinium injection and sometimes with intratumoral cysts. Total surgical resection is the treatment of choice. The outcome is favorable because the Group I patients have a 2-year survival rate of 70%. Group II is composed of 30 malignant tumors (WHO grades III and IV anaplastic astrocytoma and glioblastoma) that mainly involve the pons, with possible cranial and caudal extensions. The duration of symptoms before diagnosis is usually <3 months. MRI shows poorly delimited tumors with iso- and hyposignals in Tl-weighted sequences. Surgery is not considered helpful. The outcome is poor: The 2-year survival rate is ˜12%. Group III includes intermediate tumors, i.e., 17 patients with WHO grade II fibrillary astrocytoma. Depending on their location, duration of symptoms, and radiological features, these tumors behave differently. The prognosis is part of their behavior as tumors of Group I or Group II.

Cystic vestibular schwannomas: neuroimaging and growth rate.

In a series of 571 vestibular schwannomas (VS) operated on in the period 1976-1992, via the translabyrinthine approach, 23 tumours (4 per cent) from 23 patients were radiologically, peroperatively and histologically identified as cystic VS. Neuroimaging examinations (CT and MRI) revealed 15 tumours (2.6 per cent) with extracystic formations and in eight cases (1.4 per cent) intratumoural cysts. In 15 cases (65 per cent), tumours were located extracanalicularly with no involvement of the internal auditory canal (IAC). The extracanalicular tumour extension including the cystic elements ranged between 10 and 60 mm with a mean of 45 mm. In eight cases out of 23 (35 per cent) other diagnostic possibilities such as trigeminal schwannoma, epidermoid cyst and meningioma were proposed at the primary evaluation. Deformation, displacement and/or impression of the fourth ventricle was demonstrated in 17 cases (74 per cent). Three patients (13 per cent) had obstructive hydrocephalus which demanded shunt insertion. Residual tumour was detected in two patients (9 per cent). Growth rate in four cases was more than 10 times higher when compared to the annual growth rate of noncystic VS. The results of this study provide data on cystic VS attenuation demonstrated by CT or MRI which may be valuable in neuroradiological diagnosis of these cystic lesions and emphasizes that the wait-and-see policy should not be applied to the cystic variant of VS.

Hyperechoic renal tumors: anechoic rim and intratumoral cysts in US differentiation of renal cell carcinoma from angiomyolipoma.

To determine whether angiomyolipomas (AMLs) and renal cell carcinomas (RCCs) can be differentiated at ultrasonography (US), the authors retrospectively evaluated the sonographic appearances of 31 AMLs and 38 RCCs. Sonograms were evaluated by three radiologists without knowledge of histologic findings, with respect to the echogenicity of the tumor, predominant echotexture, and whether an anechoic rim was present. All patients had also undergone computed tomography (CT) to check for tumoral fat. Intratumoral fat was evident at CT in 28 of the 31 AMLs. RCCs had no fat at CT or histologic evaluation. An anechoic rim was evident in 32 of 38 (84%) RCCs, and 10 RCCs had small anechoic areas with back echo enhancement, which corresponded to intratumoral cysts or cystic necrosis at histologic evaluation. The anechoic rim and areas indicative of cysts were not found in AMLs. Demonstration of an anechoic rim and/or intratumoral cysts in a hyperechoic mass at US suggests that the tumor is an RCC.

MRI of intracranial subependymoma: report of a case

Subependymoma is a rare, benign intraventricular tumour and a case of septum pellucidum origin examined with CT and MR is reported. Well demarcated non-enhancing mass with multiple small intratumoral cysts is demonstrated on CT and MR images. The differential diagnosis from ependymoma has some therapeutic implications but may not be possible by CT or MRI.

Intraventricular neurocytoma: clinicopathological analysis of seven cases.

A retrospective analysis of seven patients with intraventricular neurocytoma is presented. Patient age at diagnosis ranged from 15 to 38 years (mean 24.6 years) and the male:female ratio was 6:1. Raised intracranial pressure due to hydrocephalus was the main cause of the clinical manifestations. An isodense mass with multiple intratumoral cysts and homogeneous contrast enhancement was the characteristic computerized tomography finding. The lesions commonly involved the lateral ventricle with or without extension to the third ventricle. Cerebral angiography showed homogeneous vascular staining in five patients. Magnetic resonance images revealed a mass isointense with the cerebral cortex on both T1- and T2-weighted images. Gadolinium-diethylenetriaminepenta-acetic acid-enhanced images showed homogeneous enhancement. Total removal of the tumor was possible in four patients. Pathologically, six cases were initially diagnosed as oligodendroglioma and the remaining case as ependymoma. However, immunohistochemical studies demonstrated strong positivity for neuron-specific enolase in all seven cases and for synaptophysin in five cases. On electron microscopy, three cases showed well-defined neurosecretory granules and 10-nm microtubules in their cytoplasm and cytoplasmic processes. One patient developed a recurrent tumor 18 months after surgery. The remaining six patients are free of recurrent tumors at 2 to 62 months after surgery. It is suggested that neurocytoma must be included in the differential diagnosis of intraventricular lesions, and that electron microscopic and immunohistochemical studies should be undertaken.

MR characteristics of meningioma subtypes at 1.5 tesla.

Analysis of MR signal characteristics and histopathologic findings confirms the strong correlation between meningioma subtype and observed signal intensity (SI) changes in 24 patients imaged at 1.5 T. On T2-weighted images, 90% of fibroblastic and transitional tumors were hypointense relative to cerebral cortex (SI intermediate greater than SI T2-weighted images); conversely, 66% of meningothelial subtypes displayed persistent hyperintensity (SI intermediate less than or equal to SI T2-weighted images), and the remaining one-third demonstrated mixed high-signal changes. Subtype specific differences in collagen distribution and cellularity, i.e., tumor geometry, appeared to account for these signal trends. Based solely on SI characteristics, correct histologic subgrouping of tumors as either fibroblastic/transitional or meningothelial/angioblastic was possible in 80% (19 of 24) of patients. Utilization of adjunctive imaging features (i.e., mass effect, peritumoral edema, intratumoral cyst formation) in conjunction with signal changes permitted a correct histologic pattern in 96% (23 of 24) of patients.

Spinal cord tumors: gadolinium-DTPA-enhanced MR imaging

To assess the utility of gadolinium-DTPA (Gd) and of MR imaging in the evaluation of spinal cord tumors, ten consecutive patients were prospectively evaluated. T1-proton density-, and T2-weighted images were obtained in sagittal or axial planes. T1-weighted images were obtained before and after intravenous administration. Five tumors were within the cervical spinal cord; 3 neoplasms were within the thoracic cord; 1 neoplasm extended from the cervical to the thoracic cord and 1 neoplasm extended from the cervical cord to the conus medullaris. Four tumors were ependymomas; 3 were astrocytomas; 1 was an hemangioblastoma, and 1 was a metastatic malignant peripheral nerve sheath tumor. The remaining patient died prior to spinal surgery and no autopsy was obtained. Of the precontrast sequences, tumors were best evaluated using T1-weighted images. Abnormal findings included cord widening, presence of a tumor mass, intratumoral or other associated cyst(s), and hemorrhage. Nevertheless, T1-weighted images obtained following the administration of GD were superior relative to all other pre- and post-contrast sequences for defining tumor margins, characterizing cyst(s) and delineating tumor masses. Based primarily on their appearance on post-contrast T1-weighted images, tumor-associated cysts could be subcategorized into 3 types: intratumoral cysts (found within the contrast-enhancing soft tissue mass); nonenhancing extratumoral cysts (found eitherrostral or caudal to the enhancing tumor mass); and enhancing extratumoral cysts (having an enhancing wall or containing an enhancing nodule).(ABSTRACT TRUNCATED AT 250 WORDS)

Cystic meningiomas in infancy

A suprasellar meningioma with multiple intratumoral cysts in a 6-month-old boy is reported. A review of literature disclosed only 11 cases so far. They showed a characteristic predominance in males and predominance of fibroblastic type on pathological examination. Intratumoral cystes are less common than peritumoral cysts. The various hypothesis regarding cyst formation are discussed.

Pharmacokinetic Study of Selective Continuous Internal Carotid CDDP Infusion in Malignant Brain Tumors

Cis-diamminedichloroplatinum (CDDP) was administered by selective continuous internal carotid infusion to nine patients with malignant brain tumors, including five glioblastomas, one mixed glioma, and three metastatic tumors. CDDP was infused through a catheter in the internal carotid artery at 100 mg/hr in all cases, except one glioblastoma case in which the lower rate of 10 mg/hr was used. The results of CDDP concentration measurements were: 1) CDDP in the blood peaked at termination of CDDP infusion and then decreased slowly, 2) CDDP infiltrated intratumoral cysts and accumulated there, 3) CDDP in the cerebrospinal fluid peaked 6-18 hours after infusion, and 4) the tumor/plasma CDDP ratio varied from 2 to 8. The size of tumors decreased moderately in three of the nine cases, but no complete response was achieved. The histological changes due to CDDP were observed in the tumor tissue and were absent in the normal brain parenchyma.

Placental alkaline phosphatase as a tumor marker for primary intracranial germinoma.

A sensitive enzyme-linked immunosorbent assay (ELISA) was used in a retrospective study of placental alkaline phosphatase (PLAP) levels in serum, cerebrospinal fluid (CSF), and intratumoral cyst fluid in primary intracranial germinoma. The ELISA showed no cross-reactivity with intestinal alkaline phosphatase except in very high concentrations, after samples had been heat-treated. Three patients with germinoma were studied for serum PLAP levels and in all the levels were elevated (3.78, 0.52, and 2.11 IU/liter). Two of the germinoma patients were studied for PLAP levels in the CSF, and both had elevated levels (0.83 and 9.83 IU/liter). The intratumoral cyst fluid in one case of germinoma was tested for PLAP and the level was found to be very high (603 IU/liter). These PLAP levels decreased concomitantly with the reduction in tumor size during irradiation. Serum PLAP levels were measured in 40 control adult male individuals and in the CSF of 20 nonpregnant patients with subarachnoid hemorrhage. The upper normal limits were 0.20 and 0.11 IU/liter in the serum and the CSF, respectively. All PLAP levels measured in the serum of patients with various brain tumors were 0.18 IU/liter or less. This study strongly suggests that PLAP is a clinically useful tumor marker for primary intracranial germinoma.

The various scintigraphic patterns of Warthin's tumor.

The authors' experience with salivary gland imaging in patients with Warthin's tumor was reviewed and the scans correlated with the pathologic findings of each tumor in an attempt to explain the scintigraphic variants found. Most Warthin's tumors show increased perfusion on imaging. The predischarge static images have a low sensitivity, detecting only 33% of the tumors. Warthin's tumors may appear hot, warm, or cold on the predischarge images but invariably become hot in the postdischarge study, for a 100% sensitivity. Many tumors reveal internal warm or cold areas. These focal defects correlate well with the presence of intratumoral cysts. The presence of these mixed lesions should not lead the physician away from the diagnosis of Warthin's tumor.

Computed tomography of germinomas in basal ganglia and thalamus.

CT findings of 6 cases with germinoma originating in the basal ganglia and thalamus are reported. The early finding of germinoma in this region on plain CT, was an irregularly defined, slightly high density area without mass effect. Repeated CT scanning showed enlarging iso-density lesion accompanied by mass effect to high. Intratumoral cysts and calcifications were frequently observed. The tumor showed mild to moderate and inhomogeneous enhancement by intravenous injection of contrast medium. A tendency to ipsilateral hemicerebral atrophy was found in one case. These findings were somewhat different from those of germinomas in the pineal and suprasellar regions. This phenomenon may be related to the anatomical difference of the brain where the tumor originated.

Cystic meningiomas—An update

Eighteen unusual cases of intracranial meningioma associated with a cyst are considered. Three patients were operated upon before the introduction of computed tomography scanning, and the discovery of a peritumoral cyst was unexpected. Among 15 patients studied with computed tomography, 8 had a peritumoral cyst, 6 had an intratumoral cyst, and I had a totally cystic meningioma (hypodense on computed tomography). Computed tomography permitted a correct preoperative diagnosis only in four cases. In six additional cases diagnosis was reached by selective angiographic studies. In the remaining cases diagnosis was impossible or incorrect. Different pathogenetic mechanisms underlie different radiologic patterns. The authors comment on the complex processes that lead to cyst formation in meningiomas and stress the necessity of an accurate preoperative study to avoid misdiagnosis.

Intramedullary spinal cord tumors: MR imaging, with emphasis on associated cysts.

Fifteen magnetic resonance (MR) imaging studies in 16 patients with intramedullary spinal cord lesions were correlated with surgical findings in all patients and with results of intraoperative spinal sonography (IOSS) in eight. Tumor extent was defined accurately in all but two patients by MR imaging; these lesions were found at surgery to have been underestimated by one to two vertebral body segments. Most tumors had lengthened T1 and T2 relaxation times. Intratumoral cysts were detected by MR imaging in one of eight cases, and rostral and caudal cysts were defined in only two of ten cases. The poor detection rate is attributed to poor spatial and contrast resolution. Preoperative MR imaging to define the extent of cord enlargement and IOSS to define cystic structures appears to be the optimal method of tumor management pending our further study.