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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Five patients with eighth nerve, one with ninth nerve and one with cervical neuromas were studied with PET and [18F] fluorodeoxyglucose (FDG). Four of the patients had had surgery prior to the PET study, and six patients had subsequent surgery. All tumors were well-visualized on the PET images. Only one patient with bilateral acoustic neuroma exhibited tumor recurrence or growth after the PET study; these two lesions showed the highest FDG uptakes in the PET studies (tumor-to-cerebellum ratio of 0.93-0.98). All other tumors were relatively hypometabolic (tumor-cerebellum ratios of 0.43-0.65) and showed no tumor growth or recurrence during follow-up periods ranging from 5 to 8 yr. These results suggest that PET-FDG may be of value in the evaluation of cranial and spinal schwannomas.
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PMID:PET-fluorodeoxyglucose of cranial and spinal neuromas. 143 51

The CT findings of 207 acoustic neuroma in cerebellopontine angle from 204 cases verified by operation and pathology were analysed. The following characteristics are found helpful to determine the nature of the tumor: (1) on plain scan the tumor either presents as a homogeneous isodense or slightly hypodense lesion, or as a hypodense and isodense mixed density lesion. (2) The margin of the lesion is not well defined before contrast enhancement, and it becomes clearly marginated with smooth or lobulated contour after enhancement. (3) The enhancement of a solid tumor is homogeneous or slightly inhomogeneous, but in a tumor with cystic change the enhancement is inhomogeneous or ring-like (single ring or multiple rings). (4) The center of tumor growth is located at the inner outlet of internal auditory canal. (5) The tumor attaches to the petrous bone with an acute angle. (6) The internal auditory canal is enlarged or eroded. In the differential diagnosis, usually meningioma should be considered, if the tumor is solid; and cholesteatoma and arachnoid cyst should be ruled out, if the tumor is mainly cystic.
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PMID:[CT diagnosis of acoustic neuroma of cerebellopontine angle (analysis of 204 cases)]. 278 69

Twenty-three elderly patients with acoustic neuroma have been followed conservatively (no treatment) for a mean of 3.8 years. Five patients subsequently required ventricular shunting. Two patients required partial excision of their tumors (one previously treated by shunting). Eleven patients who have required no treatment have no significant complaints. There was significant variation in tumor growth rates making predictability for surgical intervention hazardous. A mean growth rate of 0.22 cm/year was noted. Our statistics suggest tumor removal in healthy patients with larger tumors at time of presentation; in other patients, conservative follow-up may be more appropriate.
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PMID:Radiologic assessment of acoustic neuroma in the elderly. Is no treatment good treatment? 298 Apr 46

The diagnosis of acoustic neuroma is being made more easily with the advent of late-generation, high-resolution computed tomography. It is known that acoustic tumor growth in the elderly is often slow. On the other hand, it is believed that an acoustic tumor can grow very rapidly in the young. A case of acoustic neuroma in a young man with computed tomographic evidence of extremely rapid growth over a period of fifteen months is presented.
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PMID:Acoustic tumor in a young adult: documented growth rate. 359 16

BACKGROUND Understanding the tumor growth rate is very important when considering strategies for the treatment of an acoustic neuroma, although the natural course of acoustic neuromas has not been reviewed in detail. METHODS The clinicopathologic features and the postoperative growth of tumors were evaluated in 32 patients with acoustic neuromas. This study was undertaken to assess the variability of the growth potential of cells within an acoustic tumor and to determine the relationships between the growth rate and the clinicopathologic characteristics of the patients with acoustic neuromas, including age at surgery, gender, tumor location and preoperative size, the duration of the symptoms, the presence of cystic regions, the presence of Antoni type A and B cells, the tumor cell density, tumor vascularity, mitotic rate, the presence of hyaline degeneration and hemosiderin deposition, nucleolar organizer regions (NORs), and the level of proliferating cell nuclear antigen (PCNA). RESULTS The growth patterns of the tumors were divided into three groups according to their growth rate: a regression group, a "no-growth" group (growth rates from 0-0.11 cm/year) and a progression group (growth rates from 0.19-1.72 cm/year). An additional operation was required in all patients whose growth rate was more than 0.38 cm/year. A statistical study on the factors associated with an increased growth rate showed that the three histopathologic factors most significantly associated with a postoperative growth rate were hyaline degeneration (p < 0.05), cell density (p < 0.005), and PCNA labeling index (p < 0.005). CONCLUSIONS These results strongly suggest that acoustic tumors can be subdivided into several groups, based upon different biologic activities and tumor growth rates.
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PMID:Clinicopathologic growth factors of acoustic neuromas. 748 32

Due to improved diagnostic techniques, acoustic neuromas more frequently are detected at an early stage. Subsequent treatment depends on such factors as expected tumor growth rate, tumor size, and patient age. The natural history of acoustic neuromas is still uncertain: This study was performed to examine possible correlations among tumor size, patient age, signs and symptoms, and duration of symptoms. The study included 164 patients with an acoustic neuroma who were treated at University Hospital Nijmegen, The Netherlands, over a period of 13 years. Comparisons were made between the findings of this study and the reports in the literature. No support was found for any of the correlations mentioned in other studies, and no relationships could be demonstrated between the parameters evaluated in this study. The authors therefore recommend that treatment policies be based only on well-established correlations.
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PMID:Acoustic neuroma: correlation among tumor size, symptoms, and patient age. 760 73

The emergence of magnetic resonance imaging with gadolinium has dramatically enhanced our ability to accurately detect the presence of acoustic tumors as small as 2 mm in diameter. Early diagnosis and improved surgical techniques continue to reduce the morbidity associated with surgical removal of these lesions. There exists, however, a select group of patients in whom no treatment may be the most appropriate management. Since 1979, a total of 51 patients with radiographic evidence of an acoustic neuroma have been prospectively followed for tumor growth and progression of symptoms. Patients were chosen for this conservative approach on the basis of age, medical condition, tumor size, audiometric data, and patient preference. This study reveals that a significant number of patients with acoustic tumors can be safely followed with regular imaging studies and may never require treatment. Discussed are tumor growth rates, epidemiology, and the impact of these factors on patient management.
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PMID:The natural history of untreated acoustic neuromas. 807 58

Vestibular schwannoma (VS) growth potentials were studied in an in situ model, in which the cycling cellular fraction was determined immunohistochemically by applying the mouse monoclonal Ki-67 antibody, and the tumor ploidy was estimated by DNA flow cytometry in a consecutive series of 124 VSs. The tumors were classified according to the average number of positively stained nuclei in 10 high-power fields into three groups: 28 highly (> 10), 33 moderately (> 5-10) and 63 low proliferating (< or = 5). The intratumoral proliferative variation was studied in 10 tumors. Only slight variation in the number of the positively stained nuclei were observed. Six of seven tumors removed because of macroscopically documented growth by computed tomography (CAT) scan were moderately or highly proliferative. Proliferation of VS was correlated to prospectively registered clinical data. A statistically significant relation was found between VS proliferation and the prediagnostic duration of symptoms (p = 0.0001). The proliferative status was unrelated to age, sex, and tumor size. Flow-cytometric determination of DNA index of the 124 tumors revealed 12 tetraploid (DNA index = 2), 110 diploid (DNA) index = 1) and two nondiploid tumors. A statistically significant relation was noted between tumor ploidy and proliferation status expressed by Ki-67 (p = 0.024). The tetraploid tumors showed significantly lower proliferation compared with the diploid tumors. Tumor ploidy was statistically unrelated to age, sex, tumor size, and duration of symptoms. The results of this study provide a link between the immunohistochemical, flow cytometric findings, and clinical data, which could probably be relevant in identifying patients at risk for rapid tumor growth and tumor recurrences, because a rapid test for cell proliferation is now available.
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PMID:Growth of vestibular schwannomas: in situ model employing the monoclonal antibody Ki-67 and DNA flow cytometry. 872 66

A digital image analysis system was used in a retrospective analysis of MRI findings in 9 patients with acoustic neuroma. Maximum and minimum tumor diameters and surface area were measured and tumor volume was calculated. All studies included intravenous injection of gadolinium (Gd-DTPA or DOTA) and axial and coronal sections. Tumoral growth rate was analyzed using the increase in tumor size ( T) tumor area doubling time (ADT), and tumor volume doubling time (VDT). The purpose of this study was to document the growth rate of acoustic neuromas with periodic MRI. In an era in which preservation of hearing and the facial nerve is a goal of acoustic neuroma surgery, knowledge of tumor growth rate should improve patient care.
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PMID:[An analysis of the tumor growth rate in neuroma of the VIII cranial nerve using a digital image analysis system]. 1050 91

Many authors have recently reported hearing preservation for approximately two-thirds of acoustic neuroma patients. The results have driven them to recommend early surgery for all patients whose hearing might be saved. Inversely, other authors advocate that MRI-screening may be beneficial in some patients and suggest surgery only in case of tumor growth or progressive hearing loss. In order to facilitate therapeutic decision making, we reviewed the techniques and results in the main papers dealing with hearing preservation in the course of acoustic neuroma surgery published since 1990. This analysis showed that the average percentage of useful hearing preservation is about 31%. It is however difficult to compare the different series due to the different methodologies used. This emphasizes the need for standardization of hearing selection and reporting criteria to a) identify factors predictive of success (tumor characteristics, preoperative hearing, monitoring, surgical pathways), and b) elaborate well accepted decisional guidelines (early surgery or MRI screening), notably for small and non-symptomatic tumors which show increasing prevalence.
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PMID:[Hearing preservation in vestibular schwannoma surgery: indications, techniques and results in the literature since 1990]. 1101 73


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