Postradiation astrocytoma. Report of two cases

Hypothalamic Endocrine Tumors: An Update

The hypothalamus is the site of synthesis and secretion of a number of endocrine peptides that are involved in the regulation of hormonal activity of the pituitary and other endocrine targets. Tumors of the hypothalamus have been recognized to have both structural and functional effects including hormone hypersecretion. The classification of these tumors has advanced over the last few years, and biomarkers are now available to classify these tumors and provide accurate structure-function correlations. This review provides an overview of tumors in this region that is critical to metabolic homeostasis with a focus on advances in the diagnosis of gangliocytomas, neurocytomas, and pituicytomas that are unique to this region.

Secondary glioblastoma after treatment of intracranial germinoma - would radiation-only therapy still be safe? Case report

BACK GROUND

Intracranial germinomas are one of the most radiosensitive tumors and are curable by radiotherapy (RT) alone. RT-only therapy without chemotherapy is effective. But, as patients with germinoma can expect long-term survival, the adverse effects of RT and late sequelae in survivors are of most concern. So, recently, standard treatment protocol of combination with chemotherapy and reduced dose of RT could be widely acceptable.

CASE PRESENTATION

We report a patient with germinoma who developed RT-induced glioblastoma. He was diagnosed as biopsy-proven germinoma at the age of 12. Postoperatively, he underwent RT alone without chemotherapy and remained free of tumor without recurrence during long-term follow up. However, after almost 20 year, he developed RT-induced glioblastoma.

CONCLUSIONS

Although RT has the highest priority among treatments on intracranial germinomas, RT-only therapy with full dose for germinoma can have delayed severe complications. So, chemotherapy prior to reduced dose RT is more desirable.

Post-Radiation Gliomas

Aims and background

Radiotherapy is important in the treatment of neoplasm of the central nervous system, but various side effects, particularly neoplastic, have been described. Recently, post-radiation gliomas have been reported.

Methods

The authors review 88 cases of cerebral glioma following radiotherapy in patients operated for neoplasms of the nervous system, including 6 personal cases of post-radiation gliomas treated in the Neurosurgical Division of the Department of Neurological Sciences, “La Sapienza” University, Rome. The criteria used to define this unusual pathologic association are discussed.

Results

There was a male predominance. Post-radiation gliomas were particularly malignant, the average dose was 33 Gy, and average free latency was 9.6 years. The first disease was most frequently acute lymphatic leukemia.

Conclusions

Post-radiation gliomas have particular features but do not present a histologic or clinical behavior different from analogous spontaneous gliomas. The fact that 88 cases have been reported in recent years suggests that a thorough biological, clinical studies be carried out on this association.

A case of multiple radiation-induced gliomas 24 years after radiation therapy against pituitary adenoma

We treated a case in which multiple astrocytomas of varying grades developed in the irradiation field 24 years after radiation therapy. Differentiation from radiation necrosis based on presurgical diagnostic imaging was difficult; therefore, we feel it is essential to aggressively pursue histological diagnoses to select the optimal treatment method.

World Health Organization Grade II Oligodendroglioma Occurring after Successful Treatment for Childhood Acute Lymphoblastic Leukemia

When treating childhood acute lymphoblastic leukemia (ALL), secondary neoplasms are a significant long term problem. Radiation is generally accepted to be a major cause of the development of secondary neoplasms. Following treatment for ALL, a variety of secondary tumors, including brain tumors, hematologic malignancies, sarcomas, thyroid cancers, and skin cancers have been reported. However, oligodendroglioma as a secondary neoplasm is extremely rare. Herein we present a case of secondary oligodendroglioma occurring 13 years after the end of ALL treatment.

Malignant Astrocytoma of the Optic Nerve in a Child

Malignant gliomas of optic nerve and chiasm are rare, rapidly fatal neoplasms of adulthood. This report documents the occurrence of a malignant astrocytoma of the optic nerve in an 11-year-old boy who 9 years previously had a cerebellar medulloblastoma treated with surgery and irradiation. This malignant optic nerve glioma followed the same aggressive clinical course as that seen in adults, with death 9 months after diagnosis despite surgery and chemotherapy: Radiation may have been an important factor in the development of this malignant tumor which is almost never seen in the pediatric age group.

The etiology of low-grade gliomas: pathological and clinical considerations about radiation-induced low-grade gliomas

The only environmental factor undoubtedly linked to an increased risk of brain tumors (including gliomas) is therapeutic X-rays. We aim to conduct a detailed study of radiation-induced low-grade gliomas, in order to better understand the pathogenesis of such gliomas. Furthermore, we want do prove whether or not there are significant differences, according to clinical features and biological behavior, between this type of tumor and general low-grade gliomas. We analyzed the existent literature of low-grade radiation-induced glioma case reports and other epidemiological reports based on the experience of the senior author. We were able to collect 20 cases of such gliomas. Demographic data and previous X-ray details, along with latency intervals of all patients are provided. The amount of radiation able to cause mutations is not necessarily very high, as tumors occur even after low doses of radiation (as 3-5 GY). The incidence of this kind of tumors may be underestimated and may rise in the future. Care must be taken when observing patients who were irradiated more than 10 years before, especially in the recent years in which access to radiosurgical and radiation therapies has increased in the general population for treating many cerebral pathologies. Radiation-induced low-grade gliomas appear to be different from general gliomas only in terms of age in which they occur. In terms of clinical and biological behavior, there seem to be no differences, even though exceptional cases are reported.

Should adjuvant radiotherapy be recommended for pediatric craniopharyngiomas?

Intracranial tumors secondary to radiotherapy are rare. In this group gliomas are the rarest. Only 6 cases of glioblastoma multiforme (GBM) have been reported in patients undergoing radiotherapy (RT) for craniopharyngiomas of which only 4 have been in children less than 18 years of age. In recent years RT has become a mainstay of adjuvant therapy for recurrent or partially excised craniopharyngiomas. We report a child of 12 years who had previously undergone RT for a suprasellar craniopharyngioma and presented 10 years later with a GBM. This is the 5th pediatric case in literature demonstrating a GBM after RT for a craniopharyngioma. The implications of subjecting the pediatric population to RT for a benign lesion versus the outcome of gross total removal and management of RT induced tumors is discussed and the need to avail of safer alternatives such as stereotactic radiosurgery is stressed.

Malignant transformation of craniopharyngioma

Craniopharyngioma is a well recognised intracranial tumour; malignant transformation has been rarely described. In that case, malignant change occurred following irradiation for local recurrence and information is not provided on the biological behaviour of the tumour or the response to management. We report a further case of malignant transformation in recurrent craniopharyngioma following radiotherapy. The biological behaviour of malignant change in craniopharyngioma is uncertain so the treatment modalities require consideration of toxicity and other adverse sequelae balanced against anticipated outcome and comorbidities from previous treatments. The pathophysiology and therapeutic strategies are discussed. We review the possible pathogenic link between radiation therapy and malignant transformation.

Second primary glioblastoma multiforme following autologous hematopoietic stem cell transplantation in a patient with acute myelogenous leukemia

Glioblastoma multiforme (GM) is one of the most aggressive primary brain tumors, and has a poor prognosis despite intensive treatment. GM is also the most malignant astrocytoma, with histopathological features that include cellular polymorphism, rapid mitotic activity, microvascular proliferation, and necrosis. The causes of GM remain obscure, but several reports have shown associations between GM and genetic alterations and radiation exposure. Furthermore, high-dose chemotherapy/radiotherapy with autologous stem cell transplantation is increasingly being used to treat patients with leukemia, and patients who undergo stem cell transplantation have a higher risk of solid tumor cancer development later in life. Based on these associations, we discuss GM development in a patient who underwent chemoradiotherapy conditioning prior to stem cell transplantation.

Central nervous system germ cell tumors: classification, clinical features, and treatment with a historical overview

Central nervous system germ cell tumors are neoplasms that affect children and young adults. They are subclassified into germinoma and nongerminomatous germ cell tumors. The latter include teratoma (mature teratoma, immature teratoma, teratoma with malignant transformation), choriocarcinoma, embryonal carcinoma, yolk sac tumors, and mixtures of these entities. Germinoma with syncytiotrophoblastic giant cells is a variant of germinoma. Germinomas respond well to radiation therapy, but late sequelae due to irradiation have been reported. The results of radiation treatment alone for nongerminomatous germ cell tumor are not satisfactory. Combination radiochemotherapy has been applied, and this yields a good outcome with less toxicity for germinomas and better survival of nongerminomatous germ cell tumors. This article also discusses other issues, including the controversy regarding spinal irradiation and the treatment of recurrent disease.

Radiation-induced gliomas following radiotherapy for craniopharyngiomas: a case report and review of the literature

The aim of this study was to collect, describe and analyze the radiation-induced gliomas in craniopharyngioma patients reported in the literature up to date. Review of the relevant literature was performed. One personal illustrative case was added. Reports of 15 patients, including the presented illustrative case, were evaluated. The average age of the patients at the time of irradiation was 12.5 years. All patients underwent conventional fractionated radiotherapy with mean total radiation dose of 55Gy and an average latency period of 10.8 years. Glioma localization varied with the highest frequency of the temporal lobe involvement. All but one patient had high-grade gliomas on the histological exam. Although exceptionally rare, the radiation-induced gliomas in craniopharyngioma patients are potentially possible, long-term complications with devastating consequences in typically younger patients with long life-expectancy. The radiation-induced iatrogenic injury on one hand should provoke the research and elaboration of safer and at least, equally efficient alternative treatment modalities and on the other hand ought to prompt the investigation of the patients' risk factors predisposing the oncogenesis after irradiation.

Surgical management of craniopharyngiomas

Surgical treatment of craniopharyngiomas has been historically challenging and, despite advancements in microsurgical and skull base techniques, continues to pose a challenge to modern day surgeons. In particular, proponents of subtotal resection in conjunction with radiotherapy argue that this less aggressive approach can yield equivalent control rates with lower morbidity, while others argue that gross total resection is superior. Regardless of whether gross total or subtotal resection is the goal, surgical planning must include a thorough endocrine and neuro-ophthalmologic evaluation as well as imaging, and the approach, whether transsphenoidal or transcranial, must take into account the nature of the tumor and its location. In addition, optimal management of craniopharyngiomas must consist of an individualized and multidisciplinary approach not only including neurological surgery, but also including endocrinology, neuro-ophthalmology, neuropsychology, and, often, radiation-oncology.

Radiation-induced brain tumours after central nervous system irradiation in childhood: a review

OBJECTS

Radiation-induced cerebral tumours constitute a significant risk for subjects undergoing radiotherapy for the management of cerebral neoplasms. Age-related cerebral vulnerability could be a specific factor in the genesis of these complications.

METHODS

The pertinent literature of both paediatric and adult series has been reviewed. Three personal cases were added.

RESULTS

One hundred forty-two paediatric second brain tumours were evaluated. Out of them, 69 were malignant gliomas, 33 meningiomas, 8 sarcomatous lesions and 13 low-grade astrocytomas. The average latency period for the appearance of the second tumour was 8 years. Among the second tumours occurring in adults, meningioma is the most common. In this subgroup, the latency period ranged between 16 and 30 years.

CONCLUSION

Paediatric radiation-induced brain tumours differ from the adult counterpart for both the histological subtypes. These figures indicate a specific vulnerability of the infantile brain demonstrated by the most frequent occurrence of highly malignant lesions.

Radiation-induced malignant gliomas: is there a role for reirradiation?

PURPOSE

To review the literature regarding the role of radiotherapy (RT) in the treatment of patients with radiation-induced malignant gliomas (RIMGs).

METHODS AND MATERIALS

A PubMed search of English-language articles dealing with RIMG was performed, yielding 52 articles with 92 patients available for review.

RESULTS

Initial tumor types treated with RT included brain tumor in 37 patients (40%), acute lymphoblastic leukemia in 33 (36%), benign disease in 11 (12%), and other in 11 (12%). Median time from RT to development of an RIMG was 8.75 years (range, 2.5-61 years). The RIMG occurred within 10 years after RT in 81% of patients with acute lymphoblastic leukemia/lymphoma, 59% of patients with brain/other, and 18% of patients with benign conditions (p = 0.002). Type of RIMG was glioblastoma in 69 (75%) and anaplastic astrocytoma in 23 (25%). One-, 2-, and 5-year overall survival rates were 29.3%, 7.3%, and 0% for patients with glioblastoma and 59.7%, 30.3%, and 20.2% for patients with anaplastic astrocytoma. For the 85 patients with data regarding treatment for RIMG, 35 underwent reirradiation to a median dose of 50 Gy (range, 30-76 Gy). For patients undergoing reirradiation, 1-, 2- and 5-year overall survival rates were 58.9%, 20.5%, and 6.8%. For those not undergoing reirradiation, they were 15.1%, 3%, and 0% (p = 0.0009).

CONCLUSIONS

The RIMG appeared earlier in patients treated for leukemia and lymphoma and latest for those treated for a benign condition. Patients who underwent reirradiation for RIMG have longer survival times compared with those not receiving RT.

Diffuse high-grade gliomas as second malignant neoplasms after radio-chemotherapy for pediatric malignancies

OBJECTS

Diffuse high-grade gliomas are known to develop in children after cranial irradiation for other malignancies. Here, clinicopathological characteristics are outlined.

METHODS

Nine children received cranial irradiation and chemotherapy for medulloblastoma (n=2) or acute lymphoblastic leukemia (n=7). They developed a high-grade glioma 7-14 years thereafter. Clinical charts, radiologic findings, and pathologic specimens were reviewed. Archival material was stained immunohistochemically.

CONCLUSION

Gliomas evolving as second malignant neoplasms show peculiarities and differ in some aspects from their "spontaneous" counterparts. Most are supratentorial, contrast-enhancing, space-occupying lesions. They are composed mainly of small undifferentiated cells, which are mainly negative for glial fibrillary acidic protein and positive for microtubule associated proteins 2 (MAP2). Epidermal growth factor receptor labeling could not be detected in any of them. Ki67-labeling was usually high, whereas p53- and h-ras p21-staining was variable. The median survival was only 12 months despite intensive treatment.

Metachronous secondary atypical meningioma and anaplastic astrocytoma after postoperative craniospinal irradiation for medulloblastoma

INTRODUCTION

Malignant brain tumors have been reported to occur after childhood irradiation more frequently than in the nonirradiated population.

DISCUSSION

In this study, we report the case of a 15-year-old boy treated for medulloblastoma with surgery and craniospinal radiotherapy, who developed a meningioma 18 years after initial treatment and subsequently an anaplastic astrocytoma 23 years after primary treatment. The meningioma was resected without complications. The patient is currently alive but with recurrent astrocytoma after a complete remission on temozolomide monotherapy. Second malignancies are a rare, potentially devastating risk in cancer survivors, with risk continuing lifelong.

Radiation therapy in the management of pediatric craniopharyngiomas--a review

Craniopharyngiomas are benign suprasellar tumors that arise from epithelial remnants of the Rathke's pouch. The two standard treatment options are primary total resection or limited surgery followed by external beam radiation. The 10- and 20-year progression-free survival rates following limited surgery and radiation therapy are superior to those achieved by primary surgery alone. The side effect profiles for these two treatment approaches are different. Following total resection there is a very high incidence of panhypopituitarism requiring lifelong multiple hormone replacement therapy. The other side effects include potential damage to adjacent structures such as optic chiasm, vasculature and hypothalamus. Following limited surgery and radiation therapy the incidence of endocrine deficits is significantly lower compared to radical surgery, as is the risk of neurovascular and hypothalamic injury. Optic neuropathy and brain necrosis are rare in modern radiation therapy series. Second malignant neoplasms, although rare, can occur. In children with recurrent craniopharyngiomas following radical surgery, the recommended salvage treatment is radiation therapy, as further surgical attempts at salvage are associated with high relapse rates and increased morbidity and mortality. There have been significant technological advances in the field of radiation treatment planning and delivery that have great potential for reducing the incidence of long-term irradiation sequelae in the developing brain. The general availability of megavoltage linear accelerators and modern radiotherapy innovations such as three-dimensional conformal radiation treatment (3D CRT), stereotactic radiosurgery (SRS), stereotactic radiotherapy (SRT), and intensity modulated radiation therapy (IMRT) should further limit the rate of complications and improve cure rates in children with primary or recurrent craniopharyngioma.

Early adjuvant radiotherapy toward long-term survival and better quality of life for craniopharyngiomas--a study in single institute

OBJECTIVES

The objective of the study is to compare survival and quality of life (QoL) by the delivery time of adjuvant radiotherapy (RT), early or late, for craniopharyngiomas.

METHODS AND MATERIALS

Fifty patients received RT between 1985 and 2002. Early RT (n=25) was delivered within 3 months after initial surgery, whereas late RT (n=25) was combined with or without reoperation after progression or relapse. Radiation dose ranged from 45 to 55.8 Gy with a median of 54 Gy. The median follow-up was 130 months.

RESULTS

Progression-free survival rates at 5 and 10 years were 95.9 and 91.2%, respectively. The overall or progression-free survival was not influenced by RT time. Initial tumor size was the only prognostic factor (p=0.034) for progression-free survival in univariate analysis. Better visual acuity or field was maintained, and diabetes insipidus was partly improved with early RT, but all were deteriorated as tumor progressed without early RT. Visual functions were not worsened after late RT.

CONCLUSIONS

The survival was excellent with adjuvant RT, early or late. Poor QoL with late RT resulted from relapsed tumor and repeated surgery but was not associated with RT itself. Thus, early RT with precision technique is highly recommended for better QoL and excellent survival, unless contraindicated.

Pituitary radiotherapy

This article includes general comments about pituitary radiation, outcomes in patients who have Cushing's disease and adverse effects of treatment.

Glioblastoma in irradiated elderly patients: two case reports

We report our experience with two elderly patients with histologically proven diagnosis of glioblastoma multiforme who were treated 25 and 18 years earlier for tinea capitis and scalp cutaneous hemangioma respectively in the same areas where the glioblastoma multiforme had grown. These pathologies were benign, and nowadays can be treated with alternative approaches rather than radiotherapy. Radiotherapeutic treatment should be carefully considered before using it in young patients with benign pathologies who have a long life expectancy and subsequently a higher risk of developing radio-induced malignant lesions. Radio-induced gliomas are typical of patients younger than the ones with "spontaneous" glioblastomas; however, the subjects of our study were elderly (78 and 72 years).

Presentation and outcome of 93 cases of craniopharyngioma

We studied a series of 93 patients diagnosed with craniopharyngioma during a 15-year period with respect to presenting symptom, clinical course and management. The majority (62%) of patients were men, and had presented with neurological symptoms (75%), with headaches (82%) being the most common presenting symptom. The incidence of certain endocrine and ophthalmic symptoms varied little from that in the literature, on the other hand, the incidence of certain other symptoms did differ markedly from the literature. For example, loss of libido and amenorrhoea were seen at a much lower frequency than that stated in the literature. Hypertension, sensorimotor symptoms and urinary incontinence were not seen at all in our patients. In most cases diagnosis was made by a cranial CT scan, which is more sensitive than plain radiography for detection of enlarged sella turcica (69% vs. 24%; P < 0.001). In over 90% of cases, therapy consisted of removal of a variable portion of the tumour, with or without radiotherapy. Post-operative mortality was substantially reduced in cases treated by radiotherapy (P < 0.05). The most common post-operative complications in all cases were recurrence of disease, panhypopituitarism and diabetes insipidus.

Radiation-induced gliomas: report of 10 cases and review of the literature

BACKGROUND

Radiotherapy and more recently radiosurgery represent important therapeutic methods for the treatment of tumors and arterovenous malformations affecting the central nervous system, even though several significant side-effects have been described (radionecrosis, tumors, etc.). Gliomas induced by radiation therapy are decidedly unusual, and the first descriptions of this association only appeared in the 1960s.

METHODS

The pertinent literature was reviewed to yield 116 cases in which a glioma developed after radiotherapy for cranial pathologies (included 10 personal cases treated in our Institution). One of our patients had undergone radiosurgery for a cavernous angioma.

RESULTS

Patients who developed a radiation-induced glioma were younger, as a group, than those affected with so-called "spontaneous" gliomas. The tumor originated in the previously irradiated area, after average doses of 32 Gy and an average latency period of 9.6 years in accordance with the findings reported by the authors and in our experience as well. Radiotherapy had most frequently been performed for acute lymphoblastic leukemia. Our Case 10 is the fourth case of intracranial tumor arising after radiosurgery to be described in the literature.

CONCLUSIONS

Though rare, gliomas may represent a late complication of radiation treatment. The behavior of the radiation-induced variety of glioma does not seem to differ significantly from that of its "spontaneous" counterpart. Late complications of the radiosurgery are probably underestimated because of the relatively recent introduction of this technique. On the contrary, these should be scrupulously evaluated when deciding whether to employ this method for therapeutic purposes for relatively benign or congenital lesions (which generally affect young patients with a long life expectancy).

Gamma knife radiosurgery and its possible relationship to malignancy: a review

✓ The question has been raised recently whether gamma knife radiosurgery (GKS) can induce secondary neoplasia. Because there is little or no detailed knowledge about this potential complication, background information culled from the radiotherapy literature is reviewed as a guide to the clinical situations in which radiotherapy may induce secondary neoplastic change. Available case reports are then reviewed and discussed against the background of the current knowledge. On the basis of the review, the following suggestions are proposed on how to limiting the extent of this complication, document its frequency, and inform patients. It should be remembered that: the benefits of GKS are great; its alternatives also have risks; there often are no alternatives to GKS; follow-up documentation should be pursued more actively so that, if possible, no patient falls through the net; practitioners should be proactive in defining the problem, and genetic analysis of tumor biopsy specimens obtained in patients who will undergo or have undergone GKS should become routine; the extent of secondary neoplasia is not known; and patient information should be guided by what is known rather than by what is feared.

Craniopharyngioma: the St. Jude Children's Research Hospital experience 1984-2001

PURPOSE

To review our institution's experience in the treatment of craniopharyngioma and assess the merits of initial therapy with limited surgery and irradiation.

METHODS AND MATERIALS

The data of 30 patients (median age 8.6 years) with a diagnosis of craniopharyngioma between April 1984 and September 1997 were reviewed. Their course of treatment, neurologic, endocrine, and cognitive function, and quality of life at last follow-up were compared.

RESULTS

Fifteen patients were initially treated with surgery (8 required irradiation after relapse) and 15 with limited surgery and irradiation (2 required additional treatment for tumor progression). Only 1 patient died of tumor progression. The surgery group lost a mean of 9.8 points in full-scale IQ, and the combined-modality group lost only 1.25 points (p <0.063). Patients in the surgery group who had relapses (n = 9) lost a mean of 13.1 points (p <0.067). A loss of 10 points was considered clinically significant. The surgery group also had more frequent neurologic, ophthalmic, and endocrine complications. The mean Health Utility Index (a functional quality-of-life index) was higher for the combined-modality group (0.85) than for the surgery group (0.71; p <0.063, one-sided t test).

CONCLUSIONS

The acute neurologic, cognitive, and endocrine effects of surgery often affect long-term function and quality of life. Our experience suggests that limited surgery and radiotherapy cause lesser or comparable sequelae. Diabetes insipidus was the only endocrine deficiency that differed substantially in frequency between the two groups. Newer radiation planning and delivery techniques may make a combined-modality approach a good initial option for most patients.

Surgical outcomes in 31 patients with craniopharyngiomas extending outside the suprasellar cistern: an evaluation of the frontobasal interhemispheric approach

OBJECT

Craniopharyngiomas frequently grow from remnants of the Rathke pouch, which is located on the cisternal surface of the hypothalamic region. These lesions can also extend elsewhere in the infundibulohypophyseal axis. The aim of this study was to establish the usefulness of the frontobasal approach made through a relatively small craniotomy window for the removal of tumors protruding from the sellar-suprasellar region into the third and basal cistern.

METHODS

Thirty-one patients who were surgically treated for craniopharyngiomas extending outside the sellar-suprasellar region were evaluated. The diagnoses were established in all cases by using magnetic resonance and computerized tomography imaging. The initial symptoms and signs were increased intracranial pressure in eight, vision impairment or visual field defect in 16, hypopituitarism in 17, and psychological disturbances in three cases. All patients underwent surgery via the frontobasal interhemispheric approach, and the average follow-up period was 30 months. Total removal of the lesion was achieved in 22 cases, six patients underwent subtotal resection, and three underwent partial removal due to tumor recurrence after previous surgeries performed with or without adjunctive radiotherapy. Major complications, including impairment of the cranial nerves, were not observed in the immediate postoperative period. One patient exhibited transient memory disturbance due to infarction of the perforating vessels; after 3 months this symptom was ameliorated. None of the patients died during long-term follow up; however, four of the 22 who underwent total removal and six of the nine patients who underwent subtotal or partial removal suffered recurrence. Of the 10 patients with recurrence, six experienced a small recurrence of the lesion (average 3 months postsurgery); after gamma knife surgery (GKS), the size of two of the lesions was unchanged and in four reoperation was performed due to tumor enlargement during the follow-up period. Ultimately, a total of eight patients (four with recurrence and four who had been treated with GKS) underwent reoperation, with gross-total removal via the same approach or combined with the orbitozygomatic approach in patients with very short optic nerves. In no patient was deterioration of visual acuity and visual field observed after surgery. Although all patients except four children and one adult were receiving some form of hormone replacement therapy, their endocrine status was stably controllable.

CONCLUSIONS

In the authors' experience, the frontobasal interhemispheric approach, even made through a small craniotomy window, is a valid choice for the removal of craniopharyngiomas extending outside the sellar-suprasellar region. Via this approach, tumors can be removed without significant sequelae related to the surgical method, due to ease of preservation of the pituitary stalk, hypothalamic structures, and perforating vessels. This approach offers a safe and minimally invasive means of treating craniopharyngiomas.

Radiosurgery-induced brain tumor. Case report

The authors describe a case of glioblastoma multiforme (GBM) associated with previous gamma knife radiosurgery for a cerebral arteriovenous malformation (AVM). A 14-year-old boy had undergone radiosurgery for an AVM, which was performed using a 201-source 60Co gamma knife system at another institution. The maximum and margin radiation doses used in the procedure were 40 and 20 Gy, respectively. One year after radiosurgery, the patient noticed onset of mild left hemiparesis due to radiation necrosis. Six and one-half years after radiosurgery, at the age of 20 years, the patient experienced an attack of generalized tonic-clonic seizure. Magnetic resonance (MR) imaging revealed the existence of a brain tumor in the right parietal lobe. The patient underwent an operation and the histological diagnosis of the lesion was GBM. Ten months following the operation, that is, 99 months postradiosurgery, this patient died. To the best of the authors' knowledge, this is the first reported case of a neoplasm induced by radiosurgery for an AVM and the second case in which it occurred following radiosurgery for intracranial disease.

Pilocytic astrocytoma following radiotherapy for craniopharyngioma: case report

Administration of fractionated doses of irradiation is part of the adjutant therapy for CNS tumours such as craniopharyngiomas and pituitary adenomas. It can maximise cure rates or expand symptom-free period. Among the adverse effects of radiotherapy, the induction of a new tumour within the irradiated field has been frequently described. The precise clinical features that correlate irradiation and oncogenesis are not completely defined, but some authors have suggested that tumors are radiation induced when they are histologically different from the treated ones, arise in greater frequency in irradiated patients than among normal population and tend to occur in younger people with an unusual aggressiveness. In this article, we report a case of a papillary astrocytoma arising in a rather unusual latency period following radiotherapy for craniopharyngioma.

Radiographic incidence of multicentric malignant gliomas

BACKGROUND

Multicentric malignant gliomas are interesting yet uncommon clinical entities with an unknown rate of occurrence.

METHODS

We reviewed the computed tomography (CT) and magnetic resonance (MR) images of 100 consecutive patients with malignant gliomas to determine the incidence of multicentricity in malignant glial neoplasms.

RESULTS

Five patients had multiple lesions on their initial radiographic study (synchronous lesions) and in four patients multiplicity developed after initial diagnosis (metachronous lesions). MR imaging demonstrated one lesion not seen on CT.

CONCLUSIONS

Because synchronous or metachronous multicentricity was found in 9% of patients with malignant gliomas, treatment delivery should not be based on radiographic imaging without attempting to obtain an accurate diagnosis of the ongoing intracranial process.

A cerebral primitive neuroectodermal tumor in a squirrel monkey (Saimiri sciureus)

An adult squirrel monkey with a history of long-term exposure to microwave radiation was found at necropsy to have a malignant tumor of the right cerebral cortex. Gross examination revealed a mass with expanding borders in the right frontoparietal cortex with compression of the adjacent lateral ventricle. Microscopy revealed a tumor composed of sheets of moderate-sized cells, resembling an oligodendroglioma, with clear cytoplasm and central nuclei interrupted by delicate vasculature. Malignant features were present in the form of marked nuclear pleomorphism, frequent mitotic figures, and focal necrosis. A neuronal cell origin for this tumor was supported by immunohistochemical analysis, which revealed immunopositivity for neurofilament proteins and neuron-specific enolase. Staining for vimentin and glial fibrillary acid protein was negative, except in reactive astrocytes at the tumor margins and adjacent to intra-tumoral blood vessels. Antibody activity against Ki-67 antigen, a marker of rapidly proliferating tumor cells, and p53 oncoprotein was strongly positive, indicative of the aggressive and malignant nature of this tumor. The tumor was diagnosed as a cerebral primitive neuroectodermal tumor.

Secondary supratentorial anaplastic astrocytoma following treatment of medulloblastoma

The development of secondary tumours is a rare but well known late effect of radiation therapy of lesions in the central nervous system. Most radiation-induced tumours are of mesenchymal origin, but on rare occasions gliomas can occur. We describe a patient in whom a supratentorial anaplastic astrocytoma developed 15 years after surgery and radiotherapy for a childhood posterior fossa medulloblastoma. A concise review of the pertinent literature is given.

Glioma occurrence after sellar irradiation: case report and review

OBJECTIVE

Tumor neogenesis is an uncommon but known consequence after therapeutic irradiation of the central nervous system. Causative agents for glioma induction remain unknown, but laboratory and clinical data suggest a possible role for radiation as a promotor. In the treatment of both pituitary adenomas and craniopharyngiomas, adjunctive conventional radiation therapy has long played a role.

CLINICAL PRESENTATION

This report details two cases in which patients received standard sellar irradiation for growth hormone-secreting pituitary adenomas and later were diagnosed with gliomas, after a latency period of 11 and 18 years, respectively. Additionally, a comprehensive review of the literature with 30 reports of gliomas developing after conventional radiation for treatment of pituitary adenomas and craniopharyngiomas is presented. The mean dose for craniopharyngiomas (n = 8) was 5800 cGy, with a mean latency of 11.5 years from initial diagnosis to the eventual discovery of the gliomas. The mean dose for the treatment of pituitary adenomas (n = 24) was 5300 cGy, with a mean latency of 10.4 years.

CONCLUSION

Typical features of the resulting gliomas included presentation in young patients, histologically high grades, and occurrence within the temporal lobe. A large proportion of gliomas were associated with growth hormone-secreting adenomas. This review assesses the implication of doses of conventional radiotherapy that were previously thought to be benign and concludes that although radiation-associated gliomas are uncommon, they represent a potentially devastating long-term risk. Based on this analysis, treatment of sellar tumors with conventional fractionated radiotherapy should be carefully considered and perhaps used primarily in those cases for which radiosurgery is not appropriate.

Radiation-induced gliosarcoma. Case report and review of the literature

A 13-year-old boy presented with a cerebral gliosarcoma 12 years after having acute lymphoblastic leukemia treated by chemotherapy and central nervous system prophylaxis treated by radiation therapy (24 Gy) and intrathecal methotrexate. A review of the literature disclosed 129 possible radiation-induced gliomatous and/or sarcomatous brain tumors: namely, 89 gliomas, 36 sarcomas, and four gliosarcomas, including the present case. An analysis of these cases revealed several characteristics that differentiate them from similar spontaneous brain tumors, thus providing arguments for the carcinogenic effect of radiation therapy on intracranial tumors.

Radiation therapy of pineal region tumors: 25 new cases and a review of 208 previously reported cases

PURPOSE

Malignant pineal region tumors are rare neoplasms arising in midline structures of the brain. This report analyzes the influence of histology, tumor location, radiation dose, treatment volume, age and cerebrospinal fluid findings on freedom from relapse, freedom from spinal relapse and survival.

METHODS AND MATERIALS

Patient and treatment parameters of 25 cases of pineal region tumors managed at Stanford University are presented, and an additional 208 published cases were reviewed. Univariate and multivariate analysis were performed to delineate parameters predictive of freedom from relapse, freedom from spinal relapse, and survival for all 233 patients.

RESULTS

The 5- and 10-year freedom from relapse for Stanford patients was 63% and 46%, respectively. The 5- and 10-year survival for Stanford patients was 67% and 61%, respectively. The 5- and 10-year freedom from relapse for the total 233 cases was 66% and 61%, respectively. The 5- and 10-year survival for all patients was 74% and 68%, respectively. For the entire group, biopsy confirmed germinoma and non-biopsied tumors had superior freedom from relapse compared to non-germinoma germ cell tumors (p = 0.03, p = 0.005, respectively). Non-biopsied patients had improved survival compared to non-germinoma germ cell tumors (p = 0.004). Pineal parenchymal tumors had worse freedom from relapse compared to non-biopsied patients (p = 0.04). For patients with suprasellar tumors, germinomas were associated with improved freedom from relapse compared to non-germinoma germ cell tumors (p = 0.02). Simultaneous pineal and suprasellar tumors had superior survival compared to solitary tumors of pineal (p = 0.04), suprasellar (p = 0.03), or third ventricle location (p = 0.03). Twenty-two patients (9.4%) developed isolated spinal relapse. Five- and 10-year spinal relapse rates for all patients were 11% and 13%. Survival after spinal relapse was 19%. Pineal parenchymal tumors had lower freedom from spinal relapse compared to non-biopsied patients (p = 0.001). For tumors located in the pineal gland, germinomas and pineal parenchymal tumors had lower freedom from spinal relapse than did non-biopsied patients (p = 0.006, p = 0.004, respectively). Pineal germinomas had lower freedom from spinal relapse than germinomas with suprasellar location (p = 0.04). Univariate and multivariate analysis identified tumor histology as the most significant predictor of freedom from relapse, freedom from spinal relapse and survival.

CONCLUSION

Histologic type had the greatest impact on outcome. Treatment recommendations should be based on assessment of histologic type and extent of disease.

20-year experience in childhood craniopharyngioma

PURPOSE

The management of craniopharyngioma is controversial, and surgery alone is frequently advocated. The purpose of this study was to assess the long-term impact of various treatments in childhood craniopharyngioma.

METHODS AND MATERIALS

Sixty-one children < or = 21 years of age at diagnosis were treated for craniopharyngioma at Children's Hospital and the Joint Center for Radiation Therapy in Boston from 1970 to 1990. The median age was 7.5 years (range 10 months-21 years). There were 33 females and 28 males. The median follow-up was 10 years (range 2-20.5 years). Neuroimaging was available for detailed review in 53. Nine children were treated with radiotherapy alone, 15 were treated with surgery alone, and 37 were treated with both surgery and radiotherapy. All patients in the radiotherapy and surgery plus radiotherapy groups were treated with megavoltage radiation with a median dose of 5464 cGy.

RESULTS

All nine of the children treated with radiation therapy alone are alive; none have recurred. Nine of the 15 children treated with surgery alone have recurred (p = 0.007 Fisher exact test). Two are alive with disease, and seven are alive without disease after treatment at relapse with radiation therapy, surgery, or both. Seven of the 37 patients treated with surgery plus radiotherapy have recurred. Three of the seven patients are dead of disease, three patients are alive with disease, and one patient is alive without disease after further treatment. The 10-year actuarial overall survival was 91% for all patients. The 10-year actuarial freedom from progression for the surgery group was 31% compared with 100% for patients treated with radiation therapy only (log rank p = 0.01), and 86% for patients treated with surgery plus radiotherapy at diagnosis (p = 0.001). There were two treatment related deaths, both in the surgery plus radiotherapy group. A higher incidence of visual loss and diabetes insipidus was associated with the use of aggressive surgery. The size of the tumor at presentation correlated with an increased risk of recurrence; 5 of 6 patients with tumors > or = 5 cm experienced recurrences while only 6 of 30 recurred when the tumor was < 5 cm.

CONCLUSIONS

Overall survival in childhood craniopharyngioma is excellent. However, patients treated with surgery alone have a significantly worse freedom from progression when compared to patients treated with surgery and radiation therapy or radiation therapy alone.

Malignant hemispheric tumors in childhood

Sixty-four malignant hemispheric tumors in children less than 15 years old were treated in the pediatric neurosurgical department of the Hôpital des Enfants Malades between 1970 and 1989. (1) These tumors evolved rapidly in most cases. However the pre-operative evolution in 20% of the patients had a duration of more than 6 months, which favors the hypothesis that at least one-fifth of these tumors result from malignant transformation of a benign lesion. This observation should prompt neurosurgeons to operate on all benign hemispheric tumors as soon as they are diagnosed. (2) Five of the 64 patients had two successive malignant diseases. In four cases the other malignant disease was an acute lymphoblastic leukemia. (3) Among the malignant hemispheric tumors, the grade III and IV astrocytomas had a dismal prognosis. As it is known from previous studies that grade I and II astrocytomas have a good prognosis in children, it can be concluded that grading these tumors is essential. By contrast, almost one out of two patients with malignant ependymoma was alive 5 years after treatment. This implies that the grading of ependymomas is of modest prognostic values. (4) The harmful effect of radiotherapy was evaluated by comparing the functional outcome of children operated for a benign hemispheric tumor to that of children operated and irradiated for a malignant hemispheric tumor.

Medical risk factors and the development of brain tumors

Several diseases and medical treatments are discussed as risk factors for the development of brain tumors. A population-based case-control study in the Rhein-Neckar-Odenwald area (containing 1.3 million inhabitants) of Germany was established to investigate this question. A total of 226 patients (cases) with primary brain tumors (International Classification of Diseases, ninth edition, classes 191, 191.1, and 192.0) and 418 control subjects (controls) were interviewed using a standardized questionnaire over a period of 2 years. No association was seen for head injuries, hereditary diseases, family history, and radiographic examination of the head and teeth. However, more cases than controls had had meningitis (relative risk [RR], 2.7; 95% confidence interval [CI], 0.9 to 8.6) or epilepsy (RR, 2.6; 95% CI, 0.6 to 11.7). The RR was decreased for those who had allergic diseases (RR, 0.7; 95% CI, 0.5 to 1.0), diabetes (RR, 0.7; 95% CI, 0.3 to 1.8), and infections and colds (RR, 0.3; 95% CI, 0.1 to 0.8).