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BACKGROUND A trend toward the use of prolonged postoperative chemotherapy, with radiotherapy deferred until relapse, has emerged for very young children with malignant brain tumors. This study was undertaken to determine the failure patterns among infants who receive such treatment and to evaluate their responses to first salvage therapy, particularly radiotherapy, after postoperative chemotherapy. METHODS A retrospective cohort was assembled, which comprised all children younger than 36 months with biopsy-proven malignant brain tumors diagnosed during the years 1987-1993 at 3 pediatric oncology referral centers. Fifty-eight children were treated with postoperative chemotherapy without irradiation, 40 of whom experienced relapse of their malignancy. These patients' charts were reviewed for failure patterns. Thirty-five of these children received salvage therapy. Statistical and survival analysis with the Cox proportional hazards regression model was performed. RESULTS Among the 40 children who experienced relapse, 30 of 31 (97%) with solitary disease at initial diagnosis relapsed at the primary site of disease. Thirty-seven of 39 infants (95%) developed relapse that included their primary site of disease. Sixty percent of relapses were asymptomatic and were detected by magnetic resonance imaging (MRI) surveillance rather than by clinical examination. Two-year progression free survival (PFS) after relapse for infants who received salvage therapy was 29% (standard error [SE] = 8%). For infants who received radiotherapy alone, the 2-year PFS was 21% (SE = 9%). PFS did not differ according to whether relapses were detected clinically or radiographically or treated by radiotherapy, chemotherapy, surgery, or multimodal therapy. CONCLUSIONS Relapse of brain tumors in infants after prolonged postoperative chemotherapy is largely a problem of local disease control. Salvage is possible after prolonged postoperative chemotherapy, but it yields few instances of long term, progression free survival. No therapeutic modality is superior for salvage at relapse. A strategy of reserving radiotherapy for the salvage of infants whose brain tumors relapse during postoperative chemotherapy demonstrated only limited effectiveness. Cancer 1998;83:566-574. © 1998 American Cancer Society.

Objective Magnetic resonance imaging and computed tomography provide good anatomic detail of suprasellar tumors in pediatric patients but are not able to predict histology in many cases. Proton magnetic resonance spectroscopy provides metabolic data that may add to diagnostic specificity. We preoperatively performed localized proton magnetic resonance spectroscopy on pediatric patients with suprasellar tumors and correlated the results with the histological findings. Cyst fluid obtained from patients with craniopharyngiomas was studied with high-resolution magnetic resonance spectroscopy to better understand the in vivo data. Methods Nineteen patients aged 1 to 21 years underwent spectroscopy. Surgical pathological samples were obtained from 14 patients. In each of five patients, the presence of a solid chiasmatic mass in addition to clinical evidence of neurofibromatosis Type I allowed the presumptive diagnosis of chiasmatic astrocytoma. Thus, the study population included 6 patients with craniopharyngiomas, 10 with chiasmatic/hypothalamic astrocytomas, and 3 with pituitary adenomas. The data obtained were compared with those of healthy brain from age-matched participants. Results Spectroscopy was specific for the diagnosis. All craniopharyngiomas showed a dominant peak at 1 to 2 ppm, consistent with lactate or lipids, with trace amounts of other metabolites. This was confirmed using high-resolution spectroscopy. Chiasmatic gliomas showed a profile of choline, N-acetylaspartate, and creatine, and the choline:N-acetylaspartate ratio was 2.6 +/- 1.3, compared with 0.7 +/- 0.3 for samples of healthy brain (t test, P = 0.0003). Pituitary adenomas showed only a choline peak or no metabolites at all. Conclusion Proton spectroscopy may be helpful in supplementing standard imaging for the preoperative diagnosis of three types of suprasellar tumors that are common in pediatric patients.

Pre-clinical data and adult experience suggests that topoisomerase targeted anti-cancer agents may be highly schedule dependent, and efficacy may improve with prolonged exposure. To investigate this hypothesis, 28 children with recurrent brain and solid tumors were enrolled in a phase II study of oral etoposide (ETP). Patients were prescribed ETP at 50 mg/m2/ day for 21 consecutive days. Courses were repeated every 28 days pending bone marrow recovery. Evaluation of response was initially performed after 8 weeks and then every 12 weeks either by CT or MRI. Three of 4 patients with PNET (primitive neuroectodermal tumor)/medulloblastora achieved a partial response (PR). Two of 5 with ependymoma responded, one with a complete response and one with a PR. Toxicity was manageable with only 1 admission for fever and neutropenia in 120 cycles of therapy. Five patients had grade 3 or 4 neutropenia. One had grade 4 thrombocytopenia and one grade 2 mucositis and withdrew as a result. One patient had grade 2 diarrhea. Two patients who achieved a PR had received ETP as part of prior combination chemotherapy regimens. Daily oral etoposide is active in recurrent PNET/medulloblastoma and ependymoma. Toxicity is manageable and rarely requires intervention. Daily oral etoposide in combination with crosslinking agents should be considered in future phase III trials. Determination of activity in glioma and solid tumors is not complete.

Gangliogliomas account for 1-4% of all pediatric CNS tumors. We reviewed the records of 123 patients treated at the Children's Hospital of Philadelphia between 1974 and 1995. Ninety-nine patients were eligible for review with complete medical records. The mean age was 9.5 years with 52% females. The mean follow-up was 3.7 years. The most common presenting symptom was seizures (49%). The mean length of symptoms to diagnosis was 24.4 months. Complex partial seizure was the most frequent seizure type (60%). Electroencephalograms were abnormal in 36%. The majority of gangliogliomas were in the temporal lobes (38%), with other sites in the parietal (30%) and frontal lobes (18%). All patients had abnormal nonspecific neuroimaging studies. Nine received chemotherapy, and 21 were treated with radiotherapy. Postoperatively, 78% were seizure free on no medication, 18% had improvement of seizure control, and 4% had stable seizure events. Nine died of disease. Gangliogliomas are benign tumors that frequently present with seizure disorders and nonspecific electroencephalographic and neuroimaging studies. Complete surgical extirpation of these tumors provides improved seizure control in most patients and a short course of antiepileptic medical therapy. Adjuvant therapy including radiotherapy and chemotherapy is limited to recurrent disease not amenable to reoperation.

✓ The standard follow-up care for children with cerebellar astrocytomas includes regular surveillance imaging of the brain with computerized tomography or magnetic resonance. The purpose of surveillance imaging is to detect asymptomatic tumor recurrence at an early stage and permit safer reoperation. The authors evaluated the effectiveness of an intensive surveillance program for cerebellar astrocytoma and tested different models of surveillance frequency and duration to arrive at a specific recommended program. Review of the records of 93 children with typical cerebellar astrocytomas who received follow-up care between 1975 and 1993 was performed. Immediate postoperative and surveillance images were classified as showing definite, equivocal, or no tumor based on the radiology report at the time the image was obtained. Various surveillance models were then tested for their predictive value for detecting tumor recurrence. Seventeen (18%) of the 93 children had tumor recurrence or progression. Eleven of these tumors were asymptomatic and detected only by surveillance image. Tumor recurred in only one patient with a total resection, whereas tumor progression occurred in five of 21 patients with equivocal postoperative images and in 11 of 14 patients with residual tumor. A model in which patients with possible or definite residual tumor after surgery undergo surveillance at 12, 18, 30, 42, and 66 months, and later have one additional image, yielded optimum predictive value for recurrence and/or progression with the fewest images. Patients with tumor recurrence were satisfactorily treated, and only one patient died. Children with totally resected cerebellar astrocytomas do not appear to benefit from routine surveillance, because the likelihood of recurrence is small. Surveillance is of benefit in those who may have subtotal resection based on the immediate postoperative imaging.

✓ Medulloepithelioma is an uncommon childhood tumor of the central nervous system (CNS) whose histopathological appearance has been confused with medulloblastoma and other childhood primitive neuroectodermal tumors (PNETs), but which has a vastly different clinical course. The authors have reviewed the clinical features and treatment responses of eight children with these rare tumors, the largest series to date. In this series, the medulloepitheliomas were equally distributed between supratentorial and infratentorial primary sites. Four patients underwent gross- or near-total resections, one patient's tumor was partially resected, and one patient had biopsy only. Biopsy and ablative surgery were not attempted in two children with pontine tumors. Treatment included both radiation and chemotherapy (four patients), radiation alone (one patient), chemotherapy alone (one patient), and no postoperative treatment (two patients). Six patients died with a mean survival of 10 months and two are disease free with neurological impairment. Both long-term survivors underwent gross-total resections of their tumors. Postmortem examination revealed diffuse CNS tumor dissemination in four patients. Medulloepithelioma, often confused with less aggressive PNETs, can mimic intrinsic brainstem glioma, responds poorly to treatment, and is prone to CNS dissemination at the time of tumor progression.

✓ The feasibility of radical surgery for astrocytomas of the optic chiasm/hypothalamus has been reported by several groups. Such surgery carries significant risks, however, including permanent damage to the pituitary gland, optic apparatus, hypothalamic structures, and carotid arteries. The benefits of radical surgery, both in terms of efficacy and toxicity, should, therefore, be evaluated against standard therapy, as is usually done for new chemotherapeutic protocols. To this end, a retrospective review was performed of 33 patients treated at Children's Hospital of Philadelphia between 1976 and 1991 who met criteria that would have made them eligible for radical surgery in many centers today, but were treated with either no surgery or conservative surgery (< 50% resection) or biopsy followed by adjuvant therapy with local radiation therapy (29 patients) and/or chemotherapy with actinomycin-D and vincristine (18 patients). The review encompassed all children with a globular enhancing mass of at least 2 cm in the hypothalamic/chiasmatic region, no evidence of optic nerve involvement or involvement of the optic radiations by computerized tomography or magnetic resonance imaging, and follow up of at least 3 years. All but one patient had tissue confirmation of a low-grade or pilocytic astrocytoma. Thirteen of the patients were 2 years of age or younger at diagnosis. Five individuals died: three of tumor progression, one of acute shunt malfunction, and one of intercurrent infection. The remaining 28 were alive at last follow up, a mean of 10.9 years from diagnosis. Twenty-three surviving patients have functional vision in at least one eye, 12 require no endocrine replacement, and 16 are in or have completed schooling with regular academic requirements. If radical surgery is to become standard care for children with low-grade astrocytomas of the hypothalamic/chiasmatic region, long-term survival and functional outcome will have to equal or surpass those of historical controls who were treated conservatively.

Background. Gliomas of the hypothalamus and optic pathways (H/OPG) comprise 5% of pediatric intracranial tumors, present most frequently in patients younger than age 5 years, and may have a more aggressive course in younger children. This study examined clinical characteristics and consequences of treatment of young children diagnosed with H/OPG. Methods. The authors reviewed the course, treatment, and outcomes of 46 children diagnosed with H/OPG younger than age 5 years; the median follow-up was 72 months. The median age at diagnosis was 27 months. Results. Fifteen (33%) of 46 patients had neurofibromatosis-1 (NF-1).Forty children (87%) had tumor progression in the follow-up period, and tumor growth was less common in children with NF-1. Initial therapy was limited to surgical resection in three and radiation in five children. To postpone radiation until after the age of 5 years, initial therapy was limited to chemotherapy in 32 patients. Radiation was not required in 9 of these patients and was postponed for 40 months (mean) in 17. Of the 46 children, 5 died of tumor progression, 4 became blind, and 20 of 34 evaluable patients had endocrine abnormalities. Endocrinopathy did not correlate with therapy. Ten of 17 children evaluated by questionnaire required special education. There was a trend for educational problems to occur in children who were irradiated before the age of 5 years. Conclusions. Gliomas of the hypothalamus and optic pathways and their treatment cause long term morbidity in young children. Chemotherapy postpones radiation effectively, and this delay may reduce neurologic morbidity; however, 60% of children eventually relapse. By contrast, patients with NF-1 have indolent disease. Cancer 1995;75:1051-9.

OBJECTIVE: To report four children with visual impairment associated with mutism after posterior fossa surgery. Mutism after posterior fossa surgery is a well-described phenomena, but to our knowledge, visual impairment has not been reported in association with it. METHODS: Record review of four children (age range, 3-7 yr) who underwent posterior fossa surgery (via suboccipital craniotomies) for removal of a medulloblastoma (three patients) or ependymoma (one patient). Each presented with headache, ataxia, or nausea and vomiting, but none had preoperative visual complaints other than diplopia. Postoperatively, all patients were mute, and because of apparent visual loss, neuro-ophthalmic consultation was requested. Postoperative scans and examinations were also reviewed. RESULTS: Each child was awake but appeared withdrawn without verbal output. No child blinked to threat or fixed or followed. In each case, pupillary reactivity was normal, and funduscopic examinations revealed only papilledema. One child reached for money. Within weeks or months postoperatively, the mutism spontaneously resolved, and visual behavior in general improved, roughly in parallel. During the follow-up period, papilledema resolved and the disc color was normal in each case. Magnetic resonance images obtained postoperatively revealed nothing remarkable, except surgical defects, without lesions in the retrogeniculate pathway. CONCLUSION: Impaired visual behavior, mimicking cortical visual loss, may be associated with mutism after posterior fossa surgery in children. The prognosis for recovery is excellent and parallels the return of normal speech. The mechanism is unclear.

Objectives: To estimate the rate of progression of plexiform neurofibroma after surgery and to identify prognostic factors that predict progression. Study design: A retrospective review of the inpatient and outpatient records of 121 patients, who had 302 procedures on 168 tumors over a 20-year period at a single large pediatric referral center. Data on age, location, indication for surgery, and extent of resection was analyzed for prognostic significance. Results: The overall freedom from progression was 54%. Children < 10 years old had a shorter interval of tumor control than older children ( p = 0.0004). Tumors of the head/neck/face fared worse than tumors of the extremities ( p = 0.0003). Less extensive resection predicted shorter interval to progression ( p < 0.0001). Indication for surgery was not of prognostic importance. In multivariable analysis older age and location in the extremities were predictors of a better outcome. Conclusions: Tumor progression is a serious problem for children with plexiform neurofibroma. Younger children, children with tumors of the head/neck/face, and tumors that cannot be nearly completely removed are at particular risk. These data may be useful in helping clinicians decide which patients and which tumors are most likely to benefit from surgical intervention. (J Pediatr 1997;131:678-82)

Recent technological aids and understanding of pathophysiology has made the surgery of medulloblastoma safer. The guiding principle for the neurosurgeon remains removal of bulky disease, but there is no justification for removal of small amounts of tumor from critical locations. Post-operative complications include hydrocephalus, hematoma, mutism, asceptic meningitis, gastroinstestinal hemorrhage, and cervical instability. Staging is best done preoperatively with MRI, and presence of dissemination remains the most important prognostic factor in this disease. Postoperative surveillance imaging is of questionable value.