Faculty Bibliography

The 5 year survival for patients with malignant intracranial non-germinoma germ cell tumors (NGGCT) which include endodermal sinus tumors, embryonal carcinomas, choriocarcinomas and immature teratomas is less than 25% following a small resection and radiotherapy. In an effort to improve the survival of these patients, an approach using an attempt at radical resection where feasible followed by multi-modality 'sandwich' therapy (chemotherapy-radiation-chemotherapy) was used to treat 18 newly diagnosed patients between 1986 and 1994 in a multi-institution study. Fourteen patients had histologically proven NGGCT and four were presumed NGGCT because of markedly elevated concentrations of serum and/or CSF alpha fetoprotoin (AFP) and/or beta human chorionic gonadatrophin (b-HCG). The primary tumor was confined to the pineal region in 12 patients, the suprasellar region in five, and a cerebral hemisphere in one. None of the patients had central nervous system metastases at diagnosis by MRI imaging of the spine and CSF cytology. Radical surgical resection was performed initially in 11 patients (gross total -6, subtotal -5): four had a biopsy and three had no surgery. All patients then received 3 or 4 cycles of neoadjuvant chemotherapy with cisplatin (100 mg/m2/cycle) and VP-16 (500 mg/m2/cycle). Of the 12 patients with evaluable disease there were 9 responses to the neoadjuvant chemotherapy (5 CR, 4 PR); 2 patients had stable disease and I progressed during chemotherapy. Six patients with no evaluable disease after a gross total resection had a continuous complete response. Seventeen patients received radiation therapy (involved field -11, involved field + craniospinal -4, involved field + whole brain -2). Twelve patients received 4 cycles post-radiation chemotherapy with vinblastine (6.5 mg/m2/cycle). bleomycin (15 U/m2/cycle), VP-16 (300 mg/m2/cycle, carboplatin (450 mg/m2/cycle). A total of four patients have died (3-progressive/recurrent disease, 1-metabolic). Four year actuarial event-free and total survival rates are 67% and 74%. This multi-modality adjuvant therapy approach appears to dramatically improve the outcome of malignant intracranial NGGCT

We assessed the effect of cranial irradiation on hypothalamic-pituitary (HP)-adrenal function in 17 patients (12 females, 5 males) treated with cranial/ craniospinal irradiation for acute leukemia (2 patients) or tumors distant from the hypothalamus and pituitary (8 medulloblastoma, 3 astrocytoma, 3 rhabdomyosarcoma, 1 ependymoma). Estimated doses of radiation (RT) to the HP region ranged from 18 to 72 Gy. Thirteen of seventeen patients were also treated with chemotherapy. Patients were a median of 3.75 years of age (1.5-19 years) at diagnosis and were studied at a median of 5 years (0.1-20 years) after RT. Patients received corticotropin-releasing factor (oCRF, 1 microgram/kg i.v.), and sampling for cortisol and ACTH levels was performed at -15, 0, 15, 30, 60, 90 and 120 min. The-5- and 0-min levels were combined for a standardized baseline value (Base). Cortisol levels at 0, Base, 30 and 120 min, as well as the peak cortisol response, were significantly lower in the patients. Twelve of seventeen patients' peak cortisol levels fell below the normal range. The patients' mean integrated values for cortisol (area under the curve) were not, however, different from controls. The ACTH responses to oCRF did not differ between patients and controls. No relationship was observed between ACTH or cortisol responses and the time elapsed from treatment or dose of HP RT. Further, in 10 of 12 patients, 0-min dehydroepiandrosterone sulfate levels were lower than the expected normal mean levels for age, sex and pubertal status, and in 4 of these 10 patients the values were below the normal range. These data suggest that some patients treated with HP RT may be at risk for adrenal insufficiency

Recent studies have indicated that the proliferation of malignant gliomas is in part dependent on excessive activation of protein kinase C (PKC)-mediated pathways. Conversely, inhibiting PKC may provide a novel approach for blocking glioma growth. The antiestrogen tamoxifen, a moderately potent PKC inhibitor, has been shown in vitro to block the proliferation of malignant glioma cell lines at concentrations several-fold higher than those typically attained during the treatment of breast cancer; such serum concentrations may be achieved with doses > 40 mg/m2 b.i.d. The safety and efficacy of these high doses for producing disease control in patients with malignant gliomas has recently been noted anecdotally, although a rigorous study of this agent has been lacking. To address this issue, we examined the safety and efficacy of high-dose tamoxifen in a series of children with malignant gliomas that had progressed after conventional therapy. An initial group was treated with 60 mg/m2 p.o. b.i.d. and a second group with 100 mg/m2 b.i.d. Steady-state serum tamoxifen and metabolite levels were measured in most patients. Toxicity with the regimen was minimal; two patients treated at the higher dose required reduction to the lower dose because of asymptomatic prolongation of the QT interval on an electrocardiogram. Although none of the patients exhibited clear-cut tumor regression, 4 of 14 patients had stabilization of previously progressive disease for at least 3 months; the longest survivor lived for 17 months after beginning tamoxifen. The moderate efficacy of this agent in otherwise end-stage disease coupled with its low toxicity and the relative ease of oral administration provides a rationale for proceeding with larger studies of this agent in patients with malignant gliomas, possibly as a means for potentiating the effects of conventional chemotherapeutic agents, which to date have shown limited efficacy in the treatment of these tumors

The incidence of childhood brain tumors appears to be on the rise caused in part by improvements in neuroimaging and its increased availability. Current protocols for treatment of childhood brain tumors are utilizing chemotherapy more extensively in addition to and in lieu of radiotherapy to improve survival for tumors such as medulloblastoma and high grade astrocytoma, and to lessen treatment related morbidity in infants with malignant brain tumors and in older children with standard risk medulloblastomas and germ cell tumors. The increasing understanding of the molecular events that lead to oncogenesis will help unravel the causes and improve therapy for a group of illnesses that cause significant neurologic morbidity and mortality

Pallister-Hall syndrome is a human developmental disorder that is inherited in an autosomal dominant pattern. The phenotypic features of the syndrome include hypothalamic hamartoma, polydactyly, imperforate anus, laryngeal clefting, and other anomalies. Here we describe the clinical characterisation of a family with 22 affected members and the genetic mapping of the corresponding locus. Clinical, radiographic, and endoscopic evaluations showed that this disorder is a fully penetrant trait with variable expressivity and low morbidity. By analysing 60 subjects in two families using anonymous STRP markers, we have established linkage to 7p13 by two point analysis with D7S691 resulting in a lod score of 7.0 at theta = 0, near the GLI3 locus. Deletions and translocations in GLI3 are associated with the Greig cephalopolysyndactyly syndrome. Although Greig cephalopolysyndactyly syndrome has some phenotypic overlap with Pallister-Hall syndrome, these two disorders are clinically distinct. The colocalisation of loci for these distinct phenotypes led us to analyse GLI3 for mutations in patients with Pallister-Hall syndrome. We have previously shown GLI3 mutations in two other small, moderately affected families with Pallister-Hall syndrome. The linkage data reported here suggest that these larger, mildly affected families may also have mutations in GLI3

The optimum treatment of nonresectable low-grade gliomas of childhood remains undecided. There has been increased interest in the use of chemotherapy for young children, but little information concerning the long-term efficacy of such treatment. Seventy-eight children with a mean age of 3 years (range 3 months-16 years) who had newly diagnosed, progressive low-grade gliomas were treated with combined carboplatin and vincristine chemotherapy. The patients were followed for a median of 30 months from diagnosis, with 31 patients followed for more than 3 years. Fifty-eight children had diencephalic tumors, 12 had brainstem gliomas, and three had diffuse leptomeningeal gliomas. Forty-four (56%) of 78 patients showed an objective response to treatment. Progression-free survival rates were 75 +/- 6% at 2 years and 68 +/- 7% at 3 years. There was no statistical difference in progression-free survival rates between children with neurofibromatosis Type 1 and those without the disease (2-year, progression-free survival 79 +/- 11% vs. 75 +/- 6%, respectively). The histological subtype of the tumor, its location, and its maximum response to chemotherapy did not have an impact on the duration of disease control. The only significant prognostic factor was age: children 5 years old or younger at the time of treatment had a 3-year progression-free survival rate of 74 +/- 7% compared with a rate of 39 +/- 21% in older children (p < 0.01). Treatment with carboplatin and vincristine is effective, especially in younger children, in controlling newly diagnosed progressive low-grade gliomas