Faculty Bibliography

OBJECT: Controversy persists concerning the optimal treatment of craniopharyngiomas in children, and no standard outcome metric exists for comparison across treatment modalities, nor is there one that adequately reflects the multisystem dysfunction that may arise. METHODS: The authors retrospectively analyzed the records of 86 consecutive children who underwent a uniform treatment paradigm of attempted radical resection performed by a single surgeon. Excluding 3 perioperative deaths and 3 patients with inadequate follow-up, 80 children (34 girls and 46 boys; mean age 9.56 years; mean follow-up 9.6 years) composed the study group (53 primary and 27 previously treated/recurrent tumors). Building on existing classification schemes proposed by De Vile for hypothalamic dysfunction and Wen for overall functional outcome, the authors devised a more nuanced classification system (Craniopharyngioma Clinical Status Scale [CCSS]) that assesses outcome across 5 axes, including neurological examination, visual status, pituitary function, hypothalamic dysfunction, and educational/occupational status at last follow-up (there is a 4-tiered grading scale in each domain, with increasing values reflecting greater dysfunction). RESULTS: There was a significant increase in pituitary dysfunction following treatment-consistent with the high rates of diabetes insipidus and hypopituitarism common to the surgical management of craniopharyngiomas-and less dramatic deterioration in hypothalamic function or cognitive domains. Significant improvement in vision was also demonstrated, with no significant overall change in neurological status. Preoperative CCSS scores predicted postoperative outcome better than clinical characteristics like patient age, sex, tumor size, and the location or presence of hydrocephalus. CONCLUSIONS: Preoperative CCSS scores predicted outcome with higher accuracy than clinical or imaging characteristics. In lieu of randomized trials, the CCSS may provide a useful outcome assessment tool for comparison across treatment paradigms and surgical approaches. Long-term follow-up is critical to the analysis of outcomes of craniopharyngioma treatment, given the often-delayed sequelae of all therapies and the high recurrence rates of these tumors

BACKGROUND: The treatment of central nervous system (CNS) germ cell tumors (GCT) remains controversial. The purpose of this study was to demonstrate efficacy of a chemotherapy only strategy, with less morbidity, when compared to regimens with irradiation. METHODS: Between January 2001 and December 2004 newly diagnosed patients with CNS GCT were treated with one of two risk-tailored chemotherapy regimens. Twenty-five patients aged 4 months to 24.5 years were stratified: Regimen A consisted of 4-6 cycles of carboplatin/etoposide alternating with cyclophosphamide/etoposide for low risk (LR) localized germinoma with normal cerebrospinal fluid (CSF) and serum tumor markers. Regimen B consisted of 4-6 cycles of carboplatin/cyclophosphamide/etoposide for intermediate-risk (IR) germinoma with positive human chorionic gonadotrophin-beta (HCGbeta) and/or CSF HCGbeta <50 mIU/ml and high-risk (HR) biopsy-proven non-germinomatous malignant elements (MMGCT) or elevated serum/CSF alpha-fetoprotein and/or HCGbeta serum/CSF >50 mIU/ml. RESULTS: Eleven patients were classified as LR, 2 IR, and 12 HR. Seventeen (68%) patients achieved complete radiographic and marker responses after two courses and 19 (76%) after four courses of chemotherapy. Eleven patients relapsed at a mean of 30.8 months; eight of them subsequently received irradiation. The 6-year event free and overall survival for the 25 patients was 45.6% and 75.3%, respectively. CONCLUSION: These intensive chemotherapy regimens proved less effective than irradiation containing regimens. Our results indicate that, at the present time, standard treatment for CNS GCT continues to include irradiation either alone or combined with chemotherapy for pure germinomas and with chemotherapy for those with MMGCT

OBJECT: Optimal treatment of primary and recurrent craniopharyngiomas remains controversial. Radical resection and limited resection plus radiation therapy yield similar rates of disease control and overall survival. The data are much less clear for recurrent tumors. The authors report their experience with radical resection of both primary and recurrent craniopharyngiomas in children and compare the outcomes between the 2 groups. METHODS: A retrospective analysis was performed in 86 children younger than 21 years of age who underwent a total of 103 operations for craniopharyngioma between 1986 and 2008; these were performed by the senior author. The goal was resection with curative intent in all patients. Two patients were lost to follow-up and were excluded from analysis. The mean age at the time of surgery was 9.6 years, and the mean follow-up was 9.0 years. RESULTS: All 57 children with primary tumors underwent gross-total resection (GTR). A GTR was achieved in significantly fewer children with recurrent tumors (18 [62%] of 29). There were 3 perioperative deaths (3%). Tumor recurred after GTR in 14 (20%) of 71 patients. Overall survival and progression-free survival were significantly better in patients with primary tumors at time of presentation to the authors' institution. There were no significant differences in the neurological, endocrinological, visual, or functional outcomes between patients with primary and those with recurrent tumors. Factors negatively affecting overall survival and progression-free survival include subtotal resection (recurrent tumors only), tumor size >or= 5 cm, or presence of hydrocephalus or a ventriculoperitoneal shunt. Prior radiation therapy and increasing tumor size were both risk factors for incomplete resection at reoperation. CONCLUSIONS: In the hands of surgeons with experience with craniopharyngiomas, the authors believe that radical resection at presentation offers the best chance of disease control and potential cure with acceptable morbidity. While GTR does not preclude recurrence and is more difficult to achieve in recurrent tumors, especially large and previously irradiated tumors, radical resection is still possible in patients with recurrent craniopharyngiomas with morbidity similar to that of primary tumors

A choroid plexus papilloma is a rare CNS neoplasm arising from the neuroepithelial lining of the choroid plexus. A third ventricular location of a choroid plexus papilloma is rare compared with the more common sites in the lateral and fourth ventricles. Cystic choroid plexus papilloma represents an infrequent subtype that may present diagnostic ambiguity. The authors present a case of cystic choroid plexus papilloma within a cavum septum pellucidum that radiographically mimicked neurocysticercosis

OBJECT: The choice of surgical approach during resection of a thalamic juvenile pilocytic astrocytoma (JPA) is dictated by the location of the displaced normal thalamus and posterior limb of the internal capsule (PLIC). Diffusion tensor (DT) imaging and white matter tractography can identify the location of the PLIC in relation to the tumor and may be useful in planning the operative trajectory. METHODS: Diffusion tensor imaging was used to localize the PLIC on preoperative MR imaging in 6 children undergoing resection of thalamic JPAs. After review of the standard T2-weighted MR imaging sequences, the anticipated position of the PLIC was determined. This result was compared with the location of the PLIC determined by a blinded radiologist with the use of DT imaging. The utility of DT imaging in determining the surgical approach to a thalamic JPA, degree of resection, and neurological outcomes were all evaluated. RESULTS: Diffusion tensor imaging confirmed the expected location of the PLIC as approximated on conventional T2-weighted images in all 6 cases. In 1 patient in particular, unexpected medial deviation of the PLIC was identified, and this proved useful in tailoring the approach to a more lateral trajectory. Gross-total resection of all cystic and solid tumor components was confirmed on postoperative imaging in all cases. All patients experienced mild to moderate worsening of neurological status immediately following resection, but 4 of 6 patients were back to their preoperative baseline at 6-month follow-up. CONCLUSIONS: Diffusion tensor imaging and white matter tractography successfully identified the white matter fibers emanating from the precentral gyrus within the PLIC in children with thalamic JPAs prior to surgery. Diffusion tensor imaging served as a valuable tool for stereotactic planning of operative approaches to thalamic JPAs. Localizing the position of the PLIC helped minimize potential neurological morbidity and facilitated gross-total resection