Supratentorial Low-grade Astrocytoma Research Articles

Malignant transformation in low-grade astrocytoma for long-term monitoring.

Malignant transformation (MT) of low-grade astrocytoma (LGA) produces a poor prognosis in benign tumors. Currently, variables linked with MT of LGA have proven equivocal. The present study aims to evaluate the risk variables, indicating that LGA gradually differentiates to malignant astrocytoma. Retrospective cohort analysis of LGA patients was performed. Both univariate and multivariate studies were used to discover variables connected to MT using the Cox regression method. As a result, the cumulative incidence of MT for each covariate survival curve was built after the final model. In the current study, 115 individuals with LGA were included in the analysis, and MT was found in 16.5% of cases. In the case of MT, 68.4% of patients progressed to glioblastoma, whereas 31.6% progressed to anaplastic astrocytoma. Significant factors included supratentorial tumor (hazard ratio (HR) 3.41, 95% CI 1.18-12.10), midline shift > 5 mm (HR 7.15, 95% CI 2.28-34.33), and non-total resection as follows: subtotal resection (HR 5.09, 95% CI 0.07-24.02), partial resection (HR 1.61, 95% CI 1.09-24.11), and biopsy (HR 2.80, 95% CI 1.18-32.52). In individuals with LGA, MT dramatically altered the disease's natural history to a poor prognosis. The present study's analysis of the clinical features of patients indicated supratentorial LGA, a midline shift greater than 5 mm, and the degree of resection as risk factors for MT. The more extensive the resection, the greater the reduction in tumor load and MT. In addition, more molecular study is necessary to elucidate the pathophysiology of MT.

Subventricular zone predicts high velocity of tumor expansion and poor clinical outcome in patients with low grade astrocytoma

ObjectiveThe aim of this study is to clarify the association between subventricular zone (SVZ) involvement and velocity of diametric expansion(VDE) in patients with low-grade astrocytoma and also assessed the clinical outcome of those patients. Materials and MethodsA total of 168 adult patients with newly diagnosed supratentorial low-grade astrocytoma were studied retrospectively. ResultsThere were 73 patients had SVZ involvement. Patients with SVZ involvement(7.16 ± 6.53 mm/y) had a higher VDE than patients without SVZ involvement(4.38 ± 5.35 mm/y). VDE was modeled as a categorical variable(＜4, ≥4 and, ＜8, ≥8 and, ＜12, ≥12 mm/y). Logistic regression showed that SVZ involvement was associated with high VDE after adjusting by confounding variables. On the univariate analysis, the results showed that tumor involved with SVZ, VDE ≥ 4 mm/y, VDE ≥ 8 mm/y, and VDE ≥ 8 mm/y were significant predictors of a shorter OS, progression-free survival (PFS) and malignant progression-free survival (MFS)(all p ＜0.05). The categorical variables of VDE (＜4 mm/y, ≥4 mm/y and, ＜8 mm/y, ≥8 mm/y and, ＜12 mm/y, ≥12 mm/y) were adjusted by confounding variables in multivariate analysis, respectively. The results indicated that VDE ≥ 8 mm/y, VDE ≥ 12 mm/y were worse prognostic factors for OS, while VDE ≥ 4 mm/y, VDE ≥ 8 mm/y and VDE ≥ 12 mm/y were related to shorter PFS and MFS. In addition, SVZ involvement was prognostic factors in predicting OS and PFS except MFS. ConclusionOur results demonstrated that SVZ involvement predicted high VDE and worse clinical outcome, and high VDE was associated with poor prognosis in patients with low-grade astrocytoma.

Improved survival in the largest national cohort of adults with cerebellar versus supratentorial low-grade astrocytomas

Low-grade gliomas (LGGs) are indolent tumors that have the potential to dedifferentiate into malignant high-grade tumors. Recent studies have demonstrated that cerebellar low-grade tumors have a better prognosis than supratentorial tumors, although no study has focused on the risk factors for poor prognosis in cerebellar LGGs in adults. The authors of the current study aimed to address both of these concerns by using a large cohort derived from a national cancer registry and a smaller cohort derived from their institution's experience. Adults with diagnosed Grade I and Grade II gliomas of the cerebellum were identified in the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate Cox proportional hazard models were used to predict rates of survival, and the log-rank test was applied to evaluate differences in Kaplan-Meier survival curves. An institutional cohort was created by isolating all patients whose surgical pathology revealed an LGG of the cerebellum. Excluded from analysis were patients in whom a glioma was first diagnosed under the age of 18 years and those whose tumors could not be definitively determined to arise from the cerebellum. Results Data from the local cohort (11 patients) demonstrated that the most common presenting symptom was headache, which occurred in more than 70% of the cohort. Approximately half of the patients in this cohort had symptomatic improvement after treatment. from the SEER cohort (166 patients) revealed that adults with Grade I gliomas were slightly younger than those with Grade II tumors (p < 0.01), but no other demographic differences were observed. Patients with Grade I tumors were twice as likely to undergo gross-total resection (54% vs 21%), and those with Grade II gliomas were much more likely to receive postoperative radiation (3% vs 48%). Five-year survival was greater in the patients with Grade I gliomas than in those with Grade II lesions (91% vs 70%). Multivariate analysis revealed that an age ≥ 40 years (HR 7.30, 95% CI 3.55-15.0, p < 0.0001) and Grade II tumors (HR 2.76, 95% CI 1.12-6.84, p = 0.028) were risk factors for death, whereas female sex was protective (HR 0.28, 95% CI 0.14-0.59, p < 0.001). Log-rank tests revealed that a cerebellar location was protective (p < 0.0001), but this relationship was only true for Grade II tumors (p < 0.0001). Survival in patients with Grade I gliomas was not different based on the various lesion locations (p = 0.21). Taken together, adults with cerebellar WHO Grade I and II astrocytomas have a much more favorable survival curve than those with similar supratentorial tumors. Research demonstrates that the primary driver of this phenomenon is the improved survival in patients with cerebellar Grade II gliomas.

Is the Early Postoperative Radiotherapy Beneficial in Patients with Primary Supratentorial Low-grade Astrocytoma?

Is the Early Postoperative Radiotherapy Beneficial in Patients with Primary Supratentorial Low-grade Astrocytoma?

Surgical treatment of patients with low-grade astrocytomas and medically intractable seizures.

Low-grade astrocytomas can present with seizures that respond poorly to antiseizure medications, with a consequent reduction in the quality of life, because of both seizures and the medication's side-effects. We report our experience with operative treatment of such patients. Five patients (two children and three adults) with supratentorial low-grade astrocytomas associated with severe seizures were operated on. We followed the effects of the operation on post-operative neurological deficit, seizure frequency and the quality of life. No serious neurological complications followed the operations. The patients were followed for a median period of 12 months (6-46). Post-operatively, three of the patients became seizure-free, one experiences only auras, and one had a great reduction in seizure frequency and severity. All patients reported great improvement in their quality of life. Resections of low-grade astrocytomas in patients with medically intractable seizures are safe procedures that effectively control seizures in the majority of patients, resulting in significant improvement in the patients' quality of life.

Analysis of Prognostic and Survival Factors Related to Treatment of Low-Grade Astrocytomas in Adults

Prognostic factors for low-grade astrocytomas have been proposed, but optimal treatment remains controversial. Eighty-eight consecutive adult patients with supratentorial low-grade astrocytomas were retrospectively reviewed to determine specific factors influencing outcome. All underwent craniotomy (43 radical resections, 45 nonradical resections). Sex, age at diagnosis, preoperative Karnofsky performance status (KPS), tumor location, estimated extent of resection, radiation, chemotherapy, histological type, p53 status, MIB-1 staining and the apoptotic index were assessed as parameters for prognostic significance. KPS (p = 0.03), tumor location (p < 0.001), extent of surgical resection (p < 0.001) and radiotherapy (p = 0.01) were significantly assoicated with longer survival rates by univariate analysis. Multivariate analysis also showed a significant correlation between radiation therapy after surgical removal and survival time (p < 0.001). p53 status was not of importance in determining the necessity for radiotherapy. Radical surgical removal is the most important factor in the management of low-grade astrocytomas. Radiation therapy appears to be effective in improving the prognosis regardless of the extent of surgical resection or the p53 status.

Concomitant chemoradiotherapy for incompletely resected supratentorial low-grade astrocytoma in children: preliminary report.

In incompletely resected low-grade supratentorial astrocytoma, long-term survival is poor; the effect of any additional treatment to surgery still remains poorly defined. The aim of this study was to evaluate the response, the survival, and the benefit of concomitant chemoradiotherapy in eight children who had incompletely resected supratentorial low-grade astrocytoma. There were six boys and two girls, aged 4-15 years. Four tumors were in the cerebral hemispheres, one in the hemisphere and thalamus, two in the third ventricle and/or thalamus, and one in the basal ganglia. Partial resection of the tumor was performed in four patients, biopsy in four; the extent of surgery was additionally evaluated with computed tomographic (CT) and/or magnetic resonance imaging (MRI) studies. A tumor dose of 50-56 Gy was delivered postoperatively in 1.8-2.1 Gy daily fractions five times per week. Chemotherapy was intercalated concomitantly in the radiotherapy protocol: cisplatin 20 mg/m2/2 weeks intravenously (IV) and vincristine 1.5 mg/m2/week IV (up to a maximum dose of 2 mg) were planned, starting on day 1 of irradiation. There were one to three cisplatin applications and one to seven vincristine applications. Seven patients are alive 5.5-11.5 years (median, 8 years) after therapy. Six of seven are without evidence of tumor on CT and/or MRI. A residual mass is still visible in one patient, 11.5 years after therapy. He was treated at the age of 4; he is handicapped due to mental retardation and severe neurological impairment. One patient died 5 years after chemoradiotherapy, due to secondary glioblastoma multiforme, without recurrence at the site of the first tumor. Chemotherapy was discontinued in two patients because of severe nausea and vomiting; there was no hematologic or neurologic toxicity. In view of the encouraging results, all patients with incompletely resected supratentorial low-grade astrocytomas will be treated as above.

Prognostic factors for supratentorial low grade astrocytomas in adults.

The principal prognostic factors and effect on survival were retrospectively evaluated in 56 adult patients with supratentorial low grade astrocytomas treated between 1967 and 1993. Fifteen factors were evaluated with uni- and multivariate analysis to investigate their importance in predicting the length of survival. The median patient age at presentation was 42 years and the median survival was 5.0 years. The following characteristics were associated with improved patient survival by univariate analysis (p < 0.01): Age group, preoperative Karnofsky scale, and extent of surgery. Age group and Karnofsky scale were significant by multivariate analysis, but not the extent of surgery. Thus the usefulness of cytoreductive surgery in the management remains unclear, but the extent of surgery is determined by the characteristics of the tumor and the potential of the patient. Since 93% of our patients received postoperative radiotherapy, the effect of adjuvant irradiation could not be determined.

Preoperative history and postoperative survival of supratentorial low-grade astrocytomas

The preoperative history and postoperative course of histologically verified 348 low-grade and 383 anaplastic astrocytomas have been reviewed. In 71.2 and 48.0% of patients epilepsy was the initial symptom of a suspected astrocytoma, and the history was longer than 3 years in 28.1 and 19.5% of cases, respectively. Before the advent of CT, angiography was performed because of a suspected tumour 2-9 years before surgery in 34 cases. The second angiography years later demonstrated the tumour which in 18 cases at surgery proved to be low-grade astrocytoma or anaplastic astrocytoma in 16 cases. During the last 10 years CT or MRI demonstrated a low-density lesion in 21 patients years before surgery. Operation was postponed for different reasons. Ten tumours appeared at 'delayed' surgery as low-grade, but 11 as anaplastic astrocytoma. In the same period 29 further patients were operated on after a history of seizures, longer than 3 years. Histology showed anaplastic astrocytoma in 10 cases also. Malignant transformation occurred nearly in half of the patients during the observation period. This strongly suggests that dedifferentiation is a spontaneous process, an intrinsic feature of astrocytomas and does not depend on any kind of external stimulus. Another 51 patients' surgery was performed following a shorter (1-24 months) history of epilepsy. The 5-year survival rate was 44 and 39.5%. Median survival times (53.5 and 51 months) did not show a significant difference between the two groups, but the total survival, including second survivals after reoperation displayed a significant difference (57.5 vs 67.5 months) in favour of patients with a shorter history of seizures. These experiences confirm the difficulties in decision of the time of surgery. Considering the frequent malignant transformation among patients with a long history of seizures, followed by a relatively shorter survival, it may be supposed that an early radical removal in suitable cases might prevent the late dedifferentiation and recurrence.

Supratentorial low grade astrocytoma: prognostic factors, dedifferentiation, and the issue of early versus late surgery

BACKGROUNDA retrospective study of patients with low grade astrocytoma was carried out because the best management of such patients remains controversial. Prognostic factors were identified by multivariate analysis. Special attention...

O-11-174 - Supratentorial low-grade astrocytoma: Prognostic factors, deffirentiation and the issue of early versus late surgery

O-11-174 - Supratentorial low-grade astrocytoma: Prognostic factors, deffirentiation and the issue of early versus late surgery

5-year survival and clinical prognostic factors in progressive supratentorial diffuse "low-grade" astrocytoma: a retrospective analysis of 46 cases.

In order to study survival and identify prognostic factors in progressive supratentorial low grade astrocytoma, 46 cases of diffusely growing glioma (1982-1989), in which stereotactic biopsy revealed a diagnosis of astrocytoma grade II according to Kernohan, were evaluated. Only patients with definite tumour growth on consecutive CT scans were included. All patients received a full course of fractionated radiotherapy. All tumour biopsy specimens were re-evaluated according to both the Kernohan and Daumas-Duport grading systems. Follow-up for at least 5 years showed a median survival of 47.5 months (1 year 71%, 5 year 41%). In Cox' multivariate analysis 4 factors turned out to give the best fitting prognostic model for survival: age, duration of symptoms, pre-operative neurological examination and CT-contrast enhancement. Numerical scoring was performed by giving either 1 or 0 for: age > or < 40 years, symptom duration < or > 1 year, presence or absence of focal deficit, and presence or absence of CT-contrast enhancement. Combining these factors in a score ranging from 0-4 resulted in 3 distinct groups with respect to median survival (< 2:66.5 months, 2:40 months, > 2:10 months, P = 0.0015). Although 17 cases with Kernohan grade II were upgraded using Daumas-Duport criteria (13 grade III, 4 grade IV), these cases did not form a separate survival-group. Additional parameters are needed to assess prognosis by neuropathological means, as some "low-grade" tumours are less benign than others, giving rise to a variable natural history.

Variations in the natural history and survival of patients with supratentorial low-grade astrocytomas.

Data from 55 consecutive patients with low-grade astrocytomas treated between 1982 and 1990 were analyzed to determine specific outcome factors, including time to recurrence, incidence of anaplastic transformation, and survival. Gender, type of symptoms, contrast enhancement, and timing of radiation therapy were not significant in determining outcome. Patients who had symptoms for > 2 years and underwent gross-total resection of the tumor, with age as a continuous variable, were associated with significantly longer time to recurrence and survival. Within the population of patients with low-grade astrocytomas, patients with chronic epilepsy clearly had the best prognoses. There were no tumor recurrences or deaths in 27 patients with chronic epilepsy, regardless of the extent of surgery and without the use of radiotherapy. Ten-year survival was 100% for 31 patients who underwent gross-total tumor resection, regardless of the length of preoperative symptoms. Immediate postoperative radiotherapy did not prolong the time to recurrence, reduce the incidence of transition to more malignant tumors at recurrence, or increase the length of survival when compared with delayed radiotherapy. Because recurrence with a high-grade lesion caused 92% of the mortality in our series, the benefit in patients who underwent aggressive surgery seems to result from a significant decrease in the risk of recurrence when compared with patients who underwent anything less than gross-total resection. Our data also suggest that variability in the natural history of low-grade astrocytomas has a strong influence in determining survival and that tumors associated with chronic epilepsy are much less likely to become more malignant over time.

Low grade supratentorial astrocytomas. Management and prognostic factors

The authors examined the principal prognostic factors for supratentorial low grade astrocytomas and the effects of treatment on survival time. Fifty-eight patients, 32 males and 26 females, treated from January 1970 through December 1990 are reported. Thirty-five patients underwent surgery, of whom three died. Among the survivors there were 7 gross total resections, 13 subtotal resections, and 12 partial resections. Of the 23 remaining patients, diagnosis was obtained by stereotactic biopsy. Twenty-five patients were irradiated and eight received chemotherapy. The histologic material, originally graded 1 or 2 according to Kernohan's system, was reviewed using the St. Anne-Mayo Clinic system, with which there were 18 Grade 3 tumors. Six patients had pilocytic astrocytomas (mean age, 18 years), of which three astrocytomas could be removed, and the patients were well 128, 152, and 254 months, respectively, after diagnosis. Among the other three patients, one with a hypothalamic localization refused any form of treatment and died rapidly. The remaining two patients also had deep-seated tumors and were irradiated: one died 17 months later, and the other remained relapse free 56 months after diagnosis. The 49 patients with ordinary astrocytomas who survived surgery (mean age, 37 years) had a median survival time of 64 months and 5- and 10-year survival rates of 54.6% and 34.1%, respectively. Patients with Grade 1 or 2 tumors had a median survival time of 108.6 months, compared with 39.4 months for patients with Grade 3 tumors. Gross total and subtotal resections were significantly associated with longer survival time only in patients with Grade 1 and 2 tumors: in this group, the 5- and 10-year survival rates were 87.5% and 68.2%, respectively, when tumor was completely resected, instead of 57% and 31.2% in patients with incomplete or no surgical resection. There was a trend suggesting that antimitotic drugs and X-ray therapy could benefit patients with Grade 3 tumors. The importance of an accurate histologic grading system and a gross total resection of Grade 1 and 2 astrocytomas is emphasized.

Supratentorial low-grade astrocytoma. Correlation of computed tomography findings with effect of radiation therapy and prognostic variables

In supratentorial low-grade astrocytoma, radiation therapy effects and prognostic factors, especially with respect to computed tomography (CT) findings, are not yet well established. A retrospective analysis of 119 patients with this disease (histologically confirmed ordinary astrocytoma) therefore was conducted. Between 1965 and 1989, 101 patients received postoperative radiation therapy, whereas 18 patients received surgery alone. Radiation was directed to the tumor plus a 1- to 3-cm margin in almost all cases; the dose range was 41 to 66 Gy (mean, 57 Gy). CT scan was performed before treatment on 74 patients. Postoperative survival rates were compared by both univariate and multivariate analyses. The 5- and 10-year survival rates for the irradiated group were 60% and 41%, respectively, which were significantly better than those for the surgery-alone group (37% and 11%, P = 0.048). Among various potential prognostic factors for the irradiated patients, only a lower age was associated with a better prognosis. Sex, tumor site (deep-seated or not), extent of surgery, radiation dose and field, and adjuvant chemotherapy did not influence the prognosis significantly. Among various CT findings, a clear tumor margin, a maximum tumor area less than 25 cm2, presence of a cyst, and lack of mass effect were associated with a better prognosis on univariate analysis (P = 0.02-0.12), but contrast enhancement was not related to prognosis. On multivariate analysis, however, mass effect was the only significant factor. Radiation therapy appears definitely to be effective in improving the prognosis for low-grade astrocytoma. Younger age, and the absence of mass effect determined by CT, were associated significantly with a better prognosis.

Supratentorial low-grade astrocytomas in adults.

One hundred seventy-nine adult patients with supratentorial low-grade astrocytomas were treated during a 10-year period. Retrospectively, a series of nine factors were evaluated with simple and multivariate analysis to determine their importance in predicting length of survival. Four appear highly significant (P < 0.005): age, preoperative Karnofsky Performance Scale score, histological grade, and type of surgical removal. Eighty percent of patients with total removal were alive at 5 years compared with 50% with incomplete surgery and 45% with biopsy. For the group under study, the mean time for recurrence was 52 months. For patients surviving for more than 1 year, the chance of being recurrence free went from 75% at 3 years to 25% at 10 years. Among the entire population, the influence of radiotherapy was not obvious: 65% of patients were alive at 5 years without radiotherapy compared with 55% with radiotherapy. A significant difference appeared only for patients older than 40, with incomplete removal (P < 0.05); this difference did not apply to younger patients. The need for postoperative radiotherapy in all patients with subtotal removal, irrespective of their age, has not been demonstrated by this study.

Supratentorial Low-Grade Astrocytomas in Adults

ONE HUNDRED SEVENTY-NINE adult patients with supratentorial low-grade astrocytomas were treated during a 10-year period. Retrospectively, a series of nine factors were evaluated with simple and multivariate analysis to determine their importance in predicting length of survival. Four appear highly significant (P < 0.005): age, preoperative Karnofsky Performance Scale score, histological grade, and type of surgical removal. Eighty percent of patients with total removal were alive at 5 years compared with 50% with incomplete surgery and 45% with biopsy. For the group under study, the mean time for recurrence was 52 months. For patients surviving for more than 1 year, the chance of being recurrence free went from 75% at 3 years to 25% at 10 years. Among the entire population, the influence of radiotherapy was not obvious: 65% of patients were alive at 5 years without radiotherapy compared with 55% with radiotherapy. A significant difference appeared only for patients older than 40, with incomplete removal (P < 0.05); this difference did not apply to younger patients. The need for postoperative radiotherapy in all patients with subtotal removal, irrespective of their age, has not been demonstrated by this study.

Hemispheric supratentorial low-grade astrocytoma.

The records of 57 patients who were operated on at the Beilinson Medical Center from 1970 through 1982 for supratentorial low-grade astrocytomas were reviewed. The management of these patients was correlated with survival. Our study demonstrates that a younger age at onset and a negative radionuclide uptake on isotope scan, were the most important factors associated with a better survival rate. Extensive tumor resection combined with radiation therapy also exercised a beneficial effect in prolonging survival.

The Treatment of Low Grade Cerebral Astrocytomas by Radiotherapy in Queensland

The records of 108 adult patients with supratentorial low grade astrocytoma presenting between 1/1/80 and 31/12/87 were examined for the following factors which might affect survival: patient age, extent of surgical resection, site of tumour, tumour grade, radiation field size and radiation dose. Univariate analysis showed that patient age, field size and radiation dose were significant prognostic factors, but with multivariate analysis only patient age and radiation field size were significant independent variables. It is possible that field size is a proxy variable for tumour size.

Early prognosis of supratentorial grade 2 astrocytomas in adult patients after resection or stereotactic biopsy

50 adult supratentorial low-grade astrocytomas operated upon between 1984 and 1988 were analysed retrospectively with respect to postoperative condition and progression-free survival. Pilocytic lesions were excluded. In 32 instances the tumour was macroscopically completely removed and partially in 4. In 14 cases a stereotactic biopsy was performed only. 10 patients received postoperative radiotherapy with 55 to 65 Gy. 1 patient died perioperatively from pulmonary embolism. 39 patients could resume their previous activities after discharge from the hospital, 10 were significantly disabled by neurological deficit, reduced neuropsychological performance or medically intractable epilepsy. Postoperatively, most patients required continuous anti-epileptic medication, 10 recurrences or tumour progressions of incompletely removed or merely biopsied lesions were observed within the mean follow-up period of 22 months. All recurrences after gross total removal, that were reoperated, had progressed to a malignant glioma. Of the prognostic tumour characteristics analysed, a histologically well-delineated tumour demarcation was most clearly associated with a favourable prognosis. Concerning treatment modalities, gross total resection was associated with a favourable prognosis. Radiotherapy was associated with an unfavourable outcome but this is probably due to selection of otherwise unfavourable cases.