Well differentiated astrocytoma occurring nine years after radiation therapy for medulloblastoma.

Conventional treatment for medulloblastoma includes surgical resection followed by craniospinal irradiation, with the potential risk of subsequent radiotherapy-induced secondary neoplasms. We report a 23-year-old woman previously irradiated nine years earlier for a cerebellar medulloblastoma who developed a new enhancing lesion in the primary radiation field four weeks following completion of high dose chemotherapy with bone marrow transplantation for recurrent disease. Resection of this lesion revealed a low grade glioma with no evidence of recurrent medulloblastoma.

Management of pineal non-germinoma germ cell tumor with residual teratoma and normal alpha-fetoprotein.

A 16-year-old white male presented with multiple abnormal extraocular movements secondary to an enhancing pineal tumor. Subtotal resection of the lesion revealed a mixed malignant germ cell tumor. The preoperative serum alpha-fetoprotein (AFP) was markedly elevated at 155 IU/L. The patient subsequently received radiotherapy and adjuvant chemotherapy consisting of cisplatin rotating monthly with vincristine and cyclophosphamide, with dramatic tumor regression and return of AFP to normal. Eighteen months later the persistence of a substantial tumor mass despite a normal AFP raised concern for residual active tumor. Histological examination of the resected lesion revealed benign teratoma and fibrous tissue. Repeat management of mixed malignant germ cell tumors, which demonstrate a persistent mass following an initial response to treatment.

Arteriovenous malformation mimicking recurrent medulloblastoma.

Magnetic resonance imaging (MRI) is becoming the method of choice for evaluation of central nervous system tumors. However, the sensitivity of this modality raises concern that new lesions in patients previously diagnosed with a brain tumor may not necessarily represent recurrent disease. We report a patient previously treated with surgery, radiotherapy, and chemotherapy for a medulloblastoma who developed a new lesion in the floor of the fourth ventricle. Histologic review following excision revealed an arteriovenous malformation.

Surgery, hyperfractionated craniospinal irradiation, and adjuvant chemotherapy in the management of supratentorial embryonal neuroepithelial neoplasms in children.

Supratentorial embryonal neuroepithelial tumors are undifferentiated neoplasms. We have used this term in preference to the controversial classification primitive neuroectodermal tumors (PNET). These lesions in children are malignant neoplasms which are usually fatal within 2 years of diagnosis in spite of therapy with surgery, radiotherapy, and chemotherapy. We have adopted an aggressive approach to the treatment of these tumors with surgical resection, hyperfractionated craniospinal irradiation of 30.6-43.9 Gy followed by a tumor boost to a total dose of 50-63.7 Gy, and adjuvant chemotherapy with cyclophosphamide, vincristine, and cis-platinum. We have treated five children, aged 4-18 years, with this approach. In contrast to the results reported in the literature, four children are alive without evidence of tumor from 4.3 to 8.0 years following diagnosis. One has suffered a tumor relapse at 2.3 years following diagnosis but remains alive. The basis of our therapeutic strategy for childhood supratentorial embryonal neuroepithelial tumors and the implications of our clinical results are discussed.

Chemotherapy for pilocytic astrocytomas.

BACKGROUND: Although pilocytic astrocytomas (PA) generally are considered benign, a subset of patients with PA have disease progression despite standard treatment with surgery and radiation therapy. The authors report their experience with chemotherapy in this patient group. METHODS: The authors treated 11 patients (4 males and 7 females; median age at diagnosis, 8 years) with pathologically confirmed PA with chemotherapy. In eight patients, tumor progression or recurrence despite prior surgery and radiation therapy led to chemotherapy treatment. In three children younger than 5 years, chemotherapy was given in lieu of radiation therapy immediately after diagnosis (in one patient) or at the time of disease progression after surgery (in two patients). The authors used ten different chemotherapy regimens to treat the 11 patients. RESULTS: Chemotherapy produced clinical and radiographic improvement (R/R) in four (36%) patients, clinical stabilization and radiographic improvement (SD/R) in 1 (9%), clinical and radiographic stabilization (SD/SD) in 3 (27%), and was associated with clinical and radiographic progression (PD/PD) in 3 (27%). Three of the five patients with radiographic improvement had a greater than 75% reduction of maximal cross-sectional tumor area. Hematologic toxicity resulted in dose reductions in 43 of 110 (39%) total courses of chemotherapy. There were three hospitals admissions for fever and neutropenia and one chemotherapy-related death. CONCLUSIONS: The authors conclude that chemotherapy may benefit those with progressive inoperable PA. Chemotherapy may delay the need for radiation therapy in young patients with unresectable PA requiring treatment. PA may be a chemosensitive primary brain tumor.

False-positive MRI detection of recurrent or metastatic pediatric infratentorial tumors.

Gadolinium-DTPA enhanced MRI is the modality of choice when imaging central nervous system infratentorial tumors in the pediatric population. The detection of a new enhancing lesion following initiation of therapy is typically considered pathognomonic for recurrent or metastatic tumor. We report two pediatric patients with infratentorial central nervous system tumors who demonstrated new areas of enhancement with gadolinium-DTPA enhanced MRI following initiation of multimodality therapy. Both patients had surgical biopsy of the new lesions with histologic review failing to demonstrate viable tumor. These studies suggest caution in considering new enhancing lesions detected by MRI in a child with a brain tumor pathognomonic for new sites of active tumor.

Postradiation cerebellar necrosis mimicking tumor: MR appearance.

Cerebellar necrosis associated with therapy of primary gliomas is unusual. We present the MR findings in a patient with postradiation multifocal cerebellar necrosis mimicking tumor dissemination.

Comparison of serial PET and MRI scans in a pediatric patient with a brainstem glioma.

Profound clinical deficits may be associated with insults to the brainstem, making management of patients with brainstem gliomas very complex. Small changes in the radiographic appearance of a brainstem tumor may be associated with significant clinical deterioration. Furthermore, both magnetic resonance imaging and computed tomography are frequently unable to differentiate between therapy-related tissue reactions and progressive tumor. Two clinical scenarios particularly difficult to resolve include: (1) transient radiographic and clinical deterioration following hyperfractionated radiotherapy, and (2) clinical deterioration in a patient who has failed initial therapy, but has stable radiographic findings following a second therapy. We report a child with a pontine glioma whose tumor progression was demonstrated more convincingly with a 18F-deoxyglucose positron emission scan than with magnetic resonance imaging. PET scans may be helpful in confirming that tumor progression is responsible for clinical deterioration in a patient whose MRI scans remain stable.

Successful therapy for trilateral retinoblastoma.

Trilateral retinoblastoma, the intracranial malignancy associated with bilateral retinoblastoma, is an uncommon and clinically aggressive malignancy with a uniformly fatal outcome. Three children with newly diagnosed trilateral retinoblastoma were treated with systemic (cyclophosphamide and vincristine) and intrathecal (methotrexate, hydrocortisone, and cytarabine) chemotherapy, as well as craniospinal irradiation (one patient) in addition to therapy of the eye lesions. All three patients have had partial or complete response of the pineal tumors to chemotherapy, with no active disease eight or more years, 33 or more months, and 12 or more months, respectively, after diagnosis of the lesions.

Treatment of children with progressive or recurrent brain tumors with carboplatin or iproplatin: a Pediatric Oncology Group randomized phase II study.

PURPOSE: The Pediatric Oncology Group (POG) conducted a randomized phase II study to evaluate the activity of carboplatin and iproplatin in children with progressive or recurrent brain tumors. PATIENTS AND METHODS: The study was designed to evaluate the activity of these agents and to compare the toxicities associated with their use. Treatment consisted of carboplatin 560 mg/m2 at 4-week intervals or iproplatin 270 mg/m2 at 3-week intervals. RESULTS: The major toxicity observed was myelosuppression, particularly thrombocytopenia, for both agents. Ototoxicity (grade 1 or 2) was seen in 2.5% of patients treated with carboplatin and 1.3% of patients treated with iproplatin. The majority of patients with low-grade astrocytic neoplasms treated with carboplatin (nine of 12 patients) or iproplatin (eight of 12 patients) demonstrated tumor response or prolonged stable disease that persisted off-therapy. The duration of stable disease produced by carboplatin was particularly striking, ranging from 2 months to 68 + months (median, 40 + months). Neither drug demonstrated appreciable activity in the treatment of medulloblastoma (two of 26 responses to carboplatin, one of 14 responses to iproplatin), ependymoma (two of 17 responses to carboplatin, none of seven responses to iproplatin), high-grade glioma (two of 19 responses to carboplatin, one of 14 responses to iproplatin), or brain-stem tumors (one of 23 responses to carboplatin, none of 14 responses to iproplatin). CONCLUSION: Carboplatin is active against low-grade gliomas. Further evaluation of the role of carboplatin in the preirradiation treatment of children with low-grade gliomas of the optic pathway is currently underway in a clinical trial.

Phase III clinical evaluation of gadoteridol injection: experience in pediatric neuro-oncologic MR imaging.

Twenty-two pediatric patients with known CNS neoplasms underwent magnetic resonance (MR) imaging before and after intravenous injection of 0.1 mmol/kg gadoteridol injection as part of a Phase IIIB open label multicenter clinical trial. Intravenous administration of this neutral, nonionic contrast agent was found to be safe in children. No clinically relevant changes in vital signs or laboratory values (including complete blood count, blood chemistry, serum electrolytes, thyroid and metabolic panel and clotting function) were attributed to the administration of gadoteridol injection. There were no systemic complaints. The imaging characteristics of gadoteridol in pediatric CNS disease appeared similar to those of gadopentetate dimeglumine. Contrast enhancement was present in 17 of 22 patients (77%). The administration of gadoteridol injection provided additional clinically relevant information including improved visualization and delineation of the primary lesion, detection of additional lesions, determination of tumor recurrence and narrowing the list of differential considerations in all 17 enhancing studies as well as in 2 of 5 studies without signal intensity enhancement. The very low toxicity, inherent to this nonionic low osmolal paramagnetic contrast formulation may allow administration of increased doses at increased infusion rates for an increased number of indications with improved sensitivity.

Reversal of radiation-induced neutropenia by granulocyte colony-stimulating factor.

Myelosuppression is a common sequelae of radiotherapy, occasionally delaying the completion of treatment. In this report, we describe successful reversal of radiation-induced neutropenia in a child receiving craniospinal irradiation by granulocyte colony-stimulating factor (G-CSF). We suggest that G-CSF be considered as supportive care in patients in whom neutropenia develops during radiotherapy.

FDG-PET in pediatric posterior fossa brain tumors.

Seventeen pediatric patients with posterior fossa brain tumors were studied with 2-[18F]fluoro-2-deoxy-D-glucose (FDG) and positron emission tomography (PET). The FDG uptake was ranked by two observers, and the results were correlated with tumor histology. Increased FDG uptake was associated with more malignant and aggressive tumor types. Heterogeneity of FDG uptake was associated with previous therapy, including radiation therapy and chemotherapy. 2-[18F]Fluoro-2-deoxy-D-glucose PET will likely be an important adjunct in the management of pediatric posterior fossa tumors, much as in adult patients with brain tumors.

Inflammatory lesion mimicking a metastatic ependymoma.

A 2.5-year-old child who had undergone nearly total resection of an infratentorial ependymoma demonstrated a new enhancing lesion on the undersurface of the right cerebellar hemisphere 7 weeks after the initiation of adjuvant chemotherapy. The residual primary tumor demonstrated continued regression during chemotherapy, and magnetic resonance imaging of the spine and cytopathological examination of the cerebrospinal fluid showed no evidence for other sites of metastatic tumor. Because of the unusual anatomic and temporal characteristics of this lesion and despite radiographic criteria highly suspicious for a metastatic lesion, a biopsy was performed, revealing histological evidence of an inflammatory process.

Leptomeningeal dissemination of optic pathway gliomas in three children.

We treated three children with optic pathway gliomas who had progressive disease associated with metastatic spread to the leptomeninges. One patient had radiographic resolution of leptomeningeal disease after treatment with intravenous carmustine and oral mercaptopurine but died of progressive pulmonary fibrosis. The second patient was treated with intravenous thiotepa, and the leptomeningeal disease remained stable. The third patient was treated with intravenous vincristine sulfate, cyclophosphamide, cisplatin, and etoposide and had a significant size reduction of the leptomeningeal lesion. Although leptomeningeal dissemination is a seemingly rare event, it is important that all children with optic pathway gliomas be considered for this possibility, particularly after the onset of new, atypical neurologic symptoms.

Reversible neurotoxicity following hyperfractionated radiation therapy of brain stem glioma.

Two patients with brain stem gliomas were treated with hyperfractionated radiation therapy (HFR) (7,020 and 7,560 cGy, respectively). Despite initial clinical improvement during irradiation, both patients demonstrated clinical deterioration approximately 3 weeks after completion of radiotherapy. Cranial magnetic resonance imaging (MRI) revealed a progressive increase in distribution of abnormal brain stem signal consistent with either tumor or edema. 18FDG positron emission tomography (PET) was obtained in one patient and demonstrated a hypermetabolic lesion at diagnosis and a hypometabolic lesion at the time of clinical deterioration postirradiation. Management with a tapering dose of dexamethasone alone resulted in marked clinical (both patients) and radiographic (one patient) improvement, allowing reduction or discontinuation of this medication. These results suggest that patients with brain stem tumors demonstrating clinical and radiographic evidence of progressive tumor shortly after completion of HFR should be initially managed conservatively with dexamethasone, since these findings may be manifestations of reversible radiation-related neurotoxicity.

Feasibility and efficacy of preirradiation chemotherapy for pediatric brain tumors.

Preirradiation chemotherapy is a potentially important component of combined treatment for brain tumors; however, concerns over its side effects and antitumor activity have impeded its evaluation in clinical trials. To determine the feasibility of administering such therapy to children, we assessed the responses of 38 brain tumor patients (median age, 2 years) to 12 weeks of combination chemotherapy given after surgical resection but before irradiation. Transient myelosuppression was noted in all patients, but was not associated with infections or complications of surgical wounds. The ability of the patients to perform activities of daily life, as rated with the Karnofsky performance scale, was either improved (n = 14) or unchanged (n = 18) at the end of the evaluation period. In the remainder of the group, functional deterioration was clearly related to causes other than drug treatment. Prior chemotherapy did not compromise the delivery of radiation except for a brief interruption of spinal irradiation in 3 patients. Objective responses to chemotherapy, defined as a greater than 50% decrease in tumor masses, occurred in 16 of the 31 patients who had subtotal resections; only 6 patients in the entire group showed disease progression during the 12 weeks of drug administration. We conclude that chemotherapy of the type used in this study is well tolerated and produces beneficial effects in children with brain tumors.