Faculty Bibliography

The Pallister-Hall syndrome (PHS) was initially described as the congenital hypothalamic 'hamartoblastoma' syndrome in 1980. Cardinal manifestations of the syndrome consist of a hypothalamic hamartoma and extracranial abnormalities, initially thought to be fatal in the perinatal period. The original pathologic description of these hypothalamic lesions were from infants who died in the perinatal period and revealed small cells of variable density which resembled primitive undifferentiated germinal cells and appeared to invade the hypothalamic nuclei, suggesting a neoplastic potential. Hypothalamic lesions have now been removed from older infants and children with this syndrome and reveal a more mature histologic appearance typical of a hypothalamic hamartoma. We present 2 new cases of PHS who underwent surgery and demonstrate the maturational nature of the hypothalamic lesion and the phenotypic variability of the syndrome

Pathological and clinical data from 56 patients operated on for craniopharyngioma since 1981 were analyzed to determine the utility of dividing patients with this tumor into distinct clinical groups based on recognized pathological type and to determine the prognostic import of brain invasion. Of the tumors in the 30 adult patients, 66% were adamantinomatous, 28% were squamous papillary, and the remainder were mixed. However, of the tumors in the 26 children, 96% were adamantinomatous and none were pure squamous papillary (P < 0.01). Forty-six percent of the children compared with 17% of the adults had brain invasion (P < 0.01). Brain invasion was present in 37% of the adamantinomatous but in only 13% of the squamous papillary tumors. Seventy-seven percent of the children underwent gross total resection (GTR) compared with 27% of the adults (P < 0.01). Sixty-three percent of the squamous papillary tumors underwent GTR compared with 54% of the adamantinomatous and mixed tumors. Follow-up ranged from 7 to 187 months (mean, 49 mo). After subtotal resection, with or without radiation therapy, 58% of the tumors recurred compared with 17% recurrence after GTR (P < 0.01), with a mean time to recurrence of 34 months. In both tumor histological types, subtotal resection was associated with a higher rate of tumor recurrence compared with gross total resection. Among the subtotally resected craniopharyngiomas, 2 of the 3 (67%) squamous papillary and 11 of the 21 (52%) adamantinomatous and mixed tumors recurred. In contrast, among the totally resected tumors, none of the 5 squamous papillary and only 5 of the 25 (20%) adamantinomatous and mixed tumors recurred. There were no significant differences in Karnofsky performance status score, mortality rate, or visual and endocrine outcomes when comparing patients based on histological tumor type. When controlling for age and extent of resection, we found that brain invasion had no significant effect on recurrence rate in totally resected tumors. Based on the limited number of patients in this series, we conclude as follows. 1) Contrary to previous reports, squamous papillary craniopharyngiomas, like adamantinomatous tumors, may recur when subtotally resected. 2) For both tumor variants, the most significant factor associated with craniopharyngioma recurrence is the extent of surgical resection rather than histopathological subtype. 3) Contrary to prior hypotheses, brain invasion in totally resected tumors does not predict higher recurrence. 4) GTR is associated with a significantly lower recurrence rate and can be achieved without sacrificing functional outcome

We conducted a retrospective analysis of the cases of 122 children operated on for various brain tumors, to determine the incidence and natural history of postoperative diabetes insipidus (DI), and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). Abnormalities of water homeostasis were observed in 15 patients (12%). DI, with or without SIADH, was observed in 10 patients (8%), while SIADH alone was seen in five (4%). DI was permanent in five subjects (50%), whereas SIADH resolved completely in all affected individuals. Parenteral desmopressin (dDAVP) was an effective mode of therapy in the postoperative period. The effect did not correlate with a dosage strictly based on body weight

Moyamoya disease is a cerebrovascular disease characterized radiologically by progressive narrowing and occlusion of the arteries contributing to the circle of Willis and its branches. There is formation of an exuberant collateral network of blood vessels at the base of the brain, which is thought to arise in response to chronic ischemia. Clinically, the course is variable, with patients having repeated transient ischemic attacks, strokes, migraine, and seizures. Effective treatment is not available. The etiology and pathophysiology of moyamoya disease are largely unknown. Two patients with arteriographically proven moyamoya disease were identified. Both patients were symptomatic before age 5 years. Despite successful encephaloduroarteriosynangiosis revascularization procedures, they continued to experience an inexorable downhill course. A calcium channel blocker (nicardipine HCl) was introduced in order to prevent further symptoms. After the introduction of nicardipine, no further strokes occurred in either patient. There were no further episodes of transient ischemic attacks, seizures, or headache in one patient and decreased frequency in the other. In patients with moyamoya disease, nicardipine may have a beneficial effect on cerebral hemodynamics and may prevent ischemic sequelae by optimizing existing collateral circulation

PURPOSE: Very young children with CNS primitive neuroectodermal tumors (PNETs) and ependymomas have a poor prognosis and commonly have impairment of growth and cognitive abilities, in part resulting from radiotherapy. Thus, an intensive chemotherapeutic regimen was used to treat children less than 18 months of age at diagnosis. PATIENTS AND METHODS: Children were treated on a Childrens Cancer Group (CCG) protocol with an eight-drug chemotherapeutic regimen (vincristine, carmustine, procarbazine, hydroxyurea, cisplatin, cytarabine, prednisone, and cyclophosphamide) following surgery and postoperative staging. Delayed or reduced-volume radiotherapy was to be administered to all patients, but, in fact, was omitted in most cases. RESULTS: On central review of pathology, 82 children had diagnosis concordant with study entry criteria. Of these, 46 (56%) had posterior fossa (PF) PNET, eight (10%) had pineal PNET, 11 (12%) had nonpineal supratentorial PNET, 15 (18%) had ependymoma, and two had rhabdoid tumors. Fifty percent of tumor resections were complete, as verified by postoperative computed tomographic (CT) scan, and 23% of patients had metastatic disease at the time of diagnosis. Objective tumor response was documented following two cycles of chemotherapy in 28% of assessable patients. Toxicity of chemotherapy was primarily hematopoietic. Five children died of chemotherapy-related complications. Radiotherapy was administered to only nine patients before tumor progression. The 3-year progression-free survival (PFS) rates for PF PNET, pineal PNET, supratentorial nonpineal PNET, and ependymoma are 22% (SE = 6%), 0%, 55% (16%), and 26% (11%), respectively. The 3-year PFS rate for those children without metastatic disease was 29% (6%), as compared with 11% (6%) for those with metastatic disease. The only independent predictors of PFS were metastasis stage and location of the tumor within the pineal region. The median time to progression was 6 months. Twenty-four children completed the chemotherapeutic regimen without tumor progression; 19 are event-free survivors more than 2 years from diagnosis, only three of whom received radiation therapy. CONCLUSION: While overall survival in this group of very young patients is poor, a subset of children who have received only chemotherapy as adjuvant treatment remain free from tumor recurrence

Recurrence is the most common complication of all forms of treatment of craniopharyngioma. Reoperation is the preferred treatment for unsuspected residual tumor after primary radical resection. Surgical resection can be curative in the majority of recurrences, especially those with solid tumor. Scarring from previous surgery, particularly following primary radical removal, may increase the technical difficulty of surgery. Although most patients will have a reasonable functional outcome, the morbidity following operation for recurrence is greater than primary surgery with some degree of new deficit being common. Adjuvant irradiation, interstitial irradiation or bleomycin, and serial aspiration of cystic tumors have lower cure rates than surgical resection but may have lower morbidity in selected patients. They are potential adjuvant or second-line treatments for subsequent recurrence

Patients with medulloblastoma frequently present with hydrocephalus. While not all patients with medulloblastoma will continue to suffer from hydrocephalus after tumor resection, there is a significant proportion who will require a permanent shunt. We have retrospectively reviewed a group of children with medulloblastoma not shunted preoperatively, and have identified several characteristics which are associated with a requirement for permanent shunt. We studied 42 patients and found that 17 patients (40%) required permanent shunts within 4 weeks of craniotomy. The shunted patients were younger (5.4 +/- 2.9 vs. 10.0 +/- 5.7 years; p < 0.01), had larger ventricles (p < 0.05), and had more extensive tumors (Chang's stage T3 and T4; p < 0.01). These variables were all independently significant. In addition, we found that the patients requiring postcraniotomy shunts had a much higher rate of morbidity including a postoperative pseudobulbar syndrome. Of interest, we found that none of our patients without the above characteristics required a shunt. In particular, we found that no patient older than 10 years required a shunt. Thus, we conclude that younger patients with moderate to severe preoperative hydrocephalus and extensive tumors may benefit from perioperative CSF diversion. Other patients not meeting the above criteria can probably be safely managed with perioperative corticosteroids alone