Meningiomas induced by high dose cranial irradiation

Radiation-Induced Meningiomas: An Exhaustive Review of the Literature

OBJECTIVE

Radiation-induced meningioma (RIM) is an uncommon late risk of cranial irradiation. We conducted an exhaustive review of individual patient data to characterize RIM.

METHODS

Using a systematic search of the PubMed database, we performed a comprehensive literature review to characterize and investigate RIM. Student t tests were used to evaluate differences between variables. A Kaplan-Meier analysis was used to assess survival. Statistical significance was assessed using a log-rank test.

RESULTS

Our analysis included 251 cases of RIM. The average age at onset for the primary lesion was 13.0 ± 13.5 years, and the average radiation dose delivered to this lesion was 38.8 ± 16.8 Gy. Secondary meningiomas could be divided into grades I (140), II (55), and III (10) tumors. Thirty patients (11.9%) had multiple lesions, and 46 (18.3%) had recurrent meningiomas. The latency period between radiotherapy for primary lesions and the onset of meningiomas was 22.9 ± 11.4 years. The latency period was shorter for patients with grade III meningioma and for those in the high-dose and intermediate-dose radiation groups who received systemic chemotherapy. Aggressive meningiomas and multiple meningiomas were more common in the high-dose and intermediate-dose groups than in the low-dose group. The 5-year and 10-year survival rates for all patients with meningioma were 77.7% and 66.1%, respectively.

CONCLUSIONS

For patients treated with cranial radiotherapy, the risk of secondary meningioma warrants a longer follow-up period beyond the standard time frame typically designated for determining the risk of primary tumor relapse.

An Overview of Anterior Skull Base Meningiomas and the Endoscopic Endonasal Approach

Meningiomas represent 30% of all primary brain tumors. Anterior skull base meningiomas represent 8.8% of all meningiomas. Surgical resection is a main treatment option for tumors that are symptomatic and/or growing. Recurrence is directly related to the extent of resection of the tumor, the dural attachment, and pathologic bone. Endoscopic endonasal approaches represent an important addition to the treatment armamentarium for skull base meningiomas. This article provides an overview of meningiomas, with a focus on those of the anterior skull base and their management.

MIB-1 labeling index predicts recurrence in intraventricular central neurocytomas

Despite the relatively low-grade of most central neurocytomas (CN), evidence suggests the existence of an aggressive subset with a propensity for recurrence. Recent studies have found the MIB-1 labeling index to be a prognostic indicator in CN. Here we review our experience with CN to analyze the relationships between extent of resection, adjuvant therapy, tumor histology, and clinical outcomes based on aggressive histology, as defined by MIB-1 labeling. A retrospective review was performed on histologically proven CN surgically resected from 1993 to 2009 at the University of California at San Francisco. Recurrence rates were analyzed using the Kaplan-Meier method with respect to MIB-1 labeling and extent of resection. All MIB-1 labeling indices were analyzed. A total of 18 patients were identified with a mean age of 30 years (range 17-58 years) and median follow-up of 40 months (5-173 months). The treatments were: gross total resection (GTR) alone (17% of patients), subtotal resection (STR) alone (50% of patients), STR plus radiotherapy (XRT: external beam or stereotactic radiosurgery: 28% of patients), or STR plus chemotherapy (5% of patients). The extent of resection and a MIB-1 labeling index >4% was predictive of recurrence (p<0.01). In the 33% of the patients in whom the tumor recurred, all had STR with MIB-1 labeling >4% with median time to recurrence of 23.5 months. The 2-year and 4-year recurrence rates in patients with MIB-1 labeling >4% were 50% and 75% respectively. No patient with a MIB-1 labeling index <4% who received STR alone had a recurrence. Thus, in patients with CN who were treated with STR, histology demonstrating a MIB-1 labeling index >4% can be a clinically useful prognostic indicator and can help guide adjuvant treatment.

Posttreatment prognosis of patients with esthesioneuroblastoma

OBJECT

There is no Class I evidence to guide the appropriate management of esthesioneuroblastoma (EN). Most data currently guiding treatment come from small- or modest-sized series gathered at individual centers that have concluded that surgery with radiotherapy is the preferred treatment. In this study, the authors summarize the published literature on treatment outcomes in patients with EN. The objective was to ascertain what variables predict prognosis in these patients and to determine the relative effect of different therapies.

METHODS

The authors identified 205 published studies containing treatment outcomes for surgery, radiotherapy, chemotherapy, or multimodal treatment. Using Kaplan-Meier analysis, the survival of patients who received surgery was compared with that in those who received surgery and radiotherapy. Additionally, Kadish staging was compared with low- and high-grade Hyams criteria to assess for subgroup prognostic significance in survival differences.

RESULTS

Nine hundred fifty-six patients met the inclusion criteria, with a median follow-up time of 3 years. Kaplan-Meier analysis demonstrated no difference in survival between patients who underwent surgery alone and those who underwent surgery plus radiotherapy at 5 years (78 vs 75%) or 10 years (67 vs 61%, respectively) (p = 0.3). Univariate analysis demonstrated worse survival in cases involving Kadish Grade C tumors, Hyams Grade 3 and 4 tumors, and in patients older than 65 years of age. Multivariate analysis demonstrated that Hyams Grade 3 and 4 lesions carried significant risk (proportional hazard = 4.83, p < 0.001) with 5- and 10-year survival of 47 and 31%.

CONCLUSIONS

A biopsy should always be obtained in cases suspected of EN because histology is a strong prognostic indicator and will help guide appropriate treatment. Unimodal surgery and combined surgery/radiotherapy appear to be of equivalent efficacy with respect to survival in patients with EN. Chemotherapy should be considered in high-grade EN.

Possible involvement of brain tumour stem cells in the emergence of a fast-growing malignant meningioma after surgical resection and radiotherapy of high-grade astrocytoma: case report and preliminary laboratory investigation

The case of a 62-year old man diagnosed with radiation-induced meningioma (RIM) after treatment for astrocytoma with an unusually short latency period of 7 months is reported. The patient first presented with a 2-month history of memory decline. Magnetic resonance imaging (MRI) showed a tumour in the left parieto-temporal lobe. Gross total resection was performed and the tumour was confirmed to be an astrocytoma. The patient received cranial radiotherapy 2 weeks later, however 7 months after radiation treatment the patient presented with headache and vomiting. MRI showed massive meningeal enhancement in the left frontal lobe, which progressively enlarged. The patient's clinical condition deteriorated and a second craniotomy was performed with complete removal of the secondary tumour, which was shown to be a malignant meningioma. Immunohistochemical staining identified CD133-positive cells in both tumours. A rare fraction of brain tumour stem cells (BTSC) was isolated from the primary astrocytoma using a serum-free culture system, suggesting that BTSC may have been involved in the rapid emergence of RIM after resection and radiation of the primary astrocytoma.

Radiation-induced meningiomas: a shadow in the success story of childhood leukemia

While the prognosis of acute childhood leukemia has improved, long-term survivors are increasingly experiencing late effects of the treatment. Cranially irradiated survivors are predisposed to the development of CNS tumors. Our aim was to describe the incidence of secondary brain tumors and to define the significance of treatment-related risk factors and host characteristics in a cohort of childhood leukemia survivors. Our cohort consisted of 60 consecutive cranially irradiated adult survivors of childhood leukemia treated in Oulu University Hospital (Oulu, Finland); MRI of the brain was performed on 49. The sites of the tumors, their histology, and details of the leukemia treatment were determined. Of the 49 patients, 11 (22%) 1-8 years of age at the time of diagnosis developed meningioma later in life, while no other brain tumors were seen. In this cohort, the development of meningioma seemed to show undisputable linkage with long latency periods (mean, 25 years; range, 14-34 years) and an increasing incidence 20 years after the treatment (47%). Three patients had multiple meningiomas, two had recurrent disease, and one had an atypical meningioma. Age at the time of irradiation, gender, or cumulative doses of chemotherapeutic agents showed no significant association with the development of meningiomas. The high incidence of meningiomas in this study was associated with long follow-up periods. Although the cohort is small, it seems probable that the increasing incidence of meningioma will shadow the future of cranially irradiated leukemia survivors. Systematic brain imaging after the treatment is therefore justifiable.

Radiation-induced meningioma

The long-term or delayed side effects of irradiation on neural tissue are now known to include the induction of new central nervous system neoplasms. However, during the first half of the 20th century, human neural tissue was generally considered relatively resistant to the carcinogenic and other ill effects of ionizing radiation. As a result, exposure to relatively high doses of x-rays from diagnostic examinations and therapeutic treatment was common. In the present article the authors review the literature relating to radiation-induced meningiomas (RIMs). Emphasis is placed on meningiomas resulting from childhood treatment for primary brain tumor or tinea capitis, exposure to dental x-rays, and exposure to atomic explosions in Hiroshima and Nagasaki. The incidence and natural history of RIMs following exposure to high- and low-dose radiation is presented, including latency, multiplicity, histopathological features, and recurrence rates. The authors review the typical presentation of patients with RIMs and discuss unique aspects of the surgical management of these tumors compared with sporadic meningioma, based on their clinical experience in treating these lesions.

Induction of gliosarcoma and atypical meningioma 13 years after radiotherapy of residual pilocytic astrocytoma in childhood

BACKGROUND

Malignant transformation of pilocytic astrocytomas in children is rare and often linked to previous radiotherapy.

METHODS AND RESULTS

We report a patient who underwent subtotal resection of a right temporal and insular pilocytic astrocytoma at age 8 in 1988 followed by high-dose radiation therapy. A local recurrence, grade WHO III, with signs of focal sarcomatous transformation, was subtotally resected 13 years later in 2001. A new and fast growing right frontal meningioma, grade WHO II, was removed in 2003. In 2004 a second glioma recurrence was partially resected, this time graded gliosarcoma WHO IV. The patient was treated thereafter with repeated courses of temozolomide. Another tumor mass reduction in 2005 was followed by stereotactic radiotherapy. Nevertheless, he deceased 3 months later.

CONCLUSION

Most of the reported cases of malignant transformation of pilocytic astrocytomas received radiation therapy beforehand. Irradiation-induced meningiomas in children are known to occur, however not following radiotherapy of low-grade hemispheric gliomas. The presented case illustrates why adjuvant radiotherapy of residual pilocytic astrocytoma in children is not recommended anymore. For children who underwent radiotherapy in the past, we recommend MRI surveillance on a yearly basis far beyond 10 years, even in those who seem to have achieved total remission.

Women with neurofibromatosis 1 are at a moderately increased risk of developing breast cancer and should be considered for early screening

BACKGROUND

Malignancy risks in patients with neurofibromatosis 1 (NF1) are increased, but those occurring outside of the nervous system have not been clearly defined.

AIM

To evaluate the risk of breast cancer in women with NF1 in a population-based study.

METHODS

The risk of breast cancer in a cohort of 304 women with NF1 aged >or=20 years was assessed and compared with population risks over the period 1975-2005 using a person-years-at-risk analysis.

RESULTS

There were 14 cases of breast cancers in the follow-up period, yielding a standardised incidence ratio (SIR) of 3.5 (95% CI 1.9 to 5.9). However, six breast cancers occurred in women in their 40s, and the SIR of breast cancer in women aged <50 years was 4.9 (95% CI 2.4 to 8.8).

INTERPRETATION

Women with NF1 aged <50 years have a fivefold risk of breast cancer, are in the moderate risk category and should be considered for mammography from 40 years of age.