Epidemiology, natural history, and optimal management of neurohypophyseal germ cell tumors.

OBJECTIVE: Intracranial germ cell tumors (iGCTs) often arise at the neurohypophysis, their second most common origination, following the pineal region. Neurohypophyseal iGCTs present with stereotypical symptoms, including pituitary dysfunction and visual field deficit, due to their suprasellar location. The goal of this study was to present a large, longitudinal single-institution experience with neurohypophyseal iGCTs to better understand their natural history and identify opportunities for further improvement in treatment outcomes. METHODS: This is a retrospective, single-institution cohort study of neurohypophyseal iGCTs treated between 1988 and 2017, with a focus on the epidemiology, presentation, natural history, and treatment. RESULTS: Thirty-five neurosurgically managed patients met inclusion criteria; the median age was 18 years (3 months to 49 years), and 74% of patients were male (n = 26). Thirty-one tumors were germinomas, and 4 were nongerminomatous iGCTs. Presenting symptoms included pituitary insufficiency in 76% (n = 25), visual deficit in 45% (n = 15), and diabetes insipidus (DI) in 61% (n = 20) of patients. Index symptoms included isolated DI in 10 (36%), isolated hormone deficiency in 14 (50%), and concomitant DI and hormone deficiency symptoms in 4 (14%). Radiographic diagnostic latency was common, occurring at a median of 363 days (range 9-2626 days) after onset of the first symptoms and was significantly associated with both DI and hormone deficiency as the index symptoms (no DI vs DI: 360 vs 1083 days, p = 0.009; no hormone deficiency vs hormone deficiency: 245 vs 953 days, p = 0.004). Biochemical abnormalities were heterogeneous; each pituitary axis was dysfunctional in at least 1 patient, with most patients demonstrating at least 2 abnormalities, and pretreatment dysfunction demonstrating a nonsignificant trend toward association with long-term posttreatment hormone supplementation. Among germinomas, whole-brain or whole-ventricle radiotherapy demonstrated significantly improved progression-free and overall survival compared with local therapy (p = 0.009 and p = 0.004, respectively). CONCLUSIONS: Neurohypophyseal iGCTs are insidious tumors that may pose a diagnostic dilemma, as evidenced by the prolonged latency before radiographic confirmation. Serial imaging and close endocrine follow-up are recommended in patients with a characteristic clinical syndrome and negative imaging, due to the propensity for radiographic latency. Pretreatment biochemical abnormalities may indicate higher risk of posttreatment pituitary insufficiency, and all patients should receive careful endocrine follow-up. Local radiotherapy is prone to treatment failure, while whole-ventricle treatment is associated with improved survival in germinomas.

Is the blood-brain barrier really disrupted in all glioblastomas? A critical assessment of existing clinical data.

The blood-brain barrier (BBB) excludes the vast majority of cancer therapeutics from normal brain. However, the importance of the BBB in limiting drug delivery and efficacy is controversial in high-grade brain tumors, such as glioblastoma (GBM). The accumulation of normally brain impenetrant radiographic contrast material in essentially all GBM has popularized a belief that the BBB is uniformly disrupted in all GBM patients so that consideration of drug distribution across the BBB is not relevant in designing therapies for GBM. However, contrary to this view, overwhelming clinical evidence demonstrates that there is also a clinically significant tumor burden with an intact BBB in all GBM, and there is little doubt that drugs with poor BBB permeability do not provide therapeutically effective drug exposures to this fraction of tumor cells. This review provides an overview of the clinical literature to support a central hypothesis: that all GBM patients have tumor regions with an intact BBB, and cure for GBM will only be possible if these regions of tumor are adequately treated.

Maintaining clinical tissue archives and supporting human research: challenges and solutions.

CONTEXT: The increasing number of requests for use of clinically archived tissue in translational research poses unique challenges. Conflicts may arise between pathologists who are responsible for overseeing and preserving the tissues and investigators who need these materials for research purposes. OBJECTIVES: To evaluate the status of our institution's Tissue Registry Archive and to develop updated written policies and procedures to support a new modern and robust tracking system with features of a library loan system. DESIGN: An observational study was performed. RESULTS: We found the existing process for managing loans of tissue (slides and paraffin blocks) to be insufficient for the complexity and volume of this task. After extensive customization, a new tracking system was implemented in January 2008. Analysis of the first year of the system's use (2008) showed that of the 206,330 slides and 51,416 blocks loaned out in 2008, 92% and 94%, respectively, were returned by the due date. These rates were markedly improved from those before the new system: 61% and 47%, respectively, in 2005. Material permanently "lost" in 2008 represented only 0.02% of slides and 0.05% of blocks, none of which was the only diagnostic material for the case. CONCLUSIONS: With expanding needs for archived tissues for clinical care and growing demands for translational research, it is essential that pathology departments at institutions with large tissue-based research endeavors have a tracking and management system in place to meet clinical, educational, and research needs, as well as legal requirements.

Panel review of anaplastic oligodendroglioma from European Organization For Research and Treatment of Cancer Trial 26951: assessment of consensus in diagnosis, influence of 1p/19q loss, and correlations with outcome.

The diagnosis of anaplastic oligodendroglioma (AOD) or anaplastic oligoastrocytoma (AOA) is subject to interobserver variation. The aim of this study was to estimate consensus in typing and grading of these tumors using tumor material collected in a large prospective randomized phase III study and to correlate the consensus diagnosis with the 1p/19q status of the tumors and the clinical outcome. The available pathology material of the first 150 patients, randomized into the European Organization for Research and Treatment of Cancer Trial 26951, was reviewed by an independent panel of 9 neuropathologists. The presence of deletions of 1p and 19q was assessed by fluorescence in situ hybridization with locus-specific probes. The panel reached consensus on the diagnosis of AOD in 52% of the tumors that had been diagnosed as AOD by the local pathologists, whereas only 8% of the local diagnosis of AOA was confirmed with consensus. The concordance on the panel diagnosis of AOD was high (intraclass correlation = 86%). The survival curves for AOD with 1p/19q loss, AOD without these losses, and AOA without 1p/19q loss ran separately in this order. The absence of necrosis and the presence of endothelial abnormalities were correlated with better outcomes. In multivariate analysis, patients' age, 1p/19q loss, and necrosis were identified as independent prognostic factors.

Assessment and prognostic significance of mitotic index using the mitosis marker phospho-histone H3 in low and intermediate-grade infiltrating astrocytomas.

Distinguishing between grade II and grade III diffuse astrocytomas is important both for prognosis and for treatment decision-making. However, current methods for distinguishing between grades based on proliferative potential are suboptimal, making identification of clear cutoffs difficult. In this study, we compared the results from immunohistochemical staining for phospho-histone H3 (pHH3), a specific marker of cells undergoing mitosis, with standard mitotic counts (number of mitoses/10 high-power fields) and MIB-1 labeling index values for assessing proliferative activity. We tested the relationship between pHH3 staining and tumor grade and prognosis in a retrospective series of grade II and III infiltrating astrocytomas from a single institution. The pHH3 index (per 1000 cells), MIB-1 index (per 1000 cells), and number of mitoses per 10 high-power fields were determined for each of 103 cases of grade II and III diffuse astrocytomas from patients with clinical follow-up. pHH3 staining was found to be a simple and reliable method for identifying mitotic figures, allowing a true mitotic index to be determined. The pHH3 mitotic index was significantly associated both with the standard mitotic count and with the MIB-1 index. Univariate analyses revealed that all 3 measurements of proliferation were significantly associated with survival. However, the pHH3 mitotic index accounted for a larger proportion of variability in survival than standard mitotic count or MIB-1/Ki-67 labeling index. After adjusting for age, extent of resection, and performance score, the pHH3 mitotic index remained an independent predictor of survival. Thus, pHH3 staining provides a simple and reliable method for quantifying proliferative potential and for the stratification of patients with diffuse astrocytomas into typical grade II and III groups. These results also suggest that pHH3 staining may be a useful method in other neoplasms in which accurate determination of proliferation potential is relevant to tumor grading or clinical treatment decision-making.