Preclinical validation of a novel therapeutic strategy for choroid plexus carcinoma.

Choroid plexus carcinoma (CPC) is a rare infantile brain tumor with an aggressive clinical course that often leaves children with debilitating side effects due to aggressive and toxic chemotherapies. Development of novel therapeutical strategies for this disease have been extremely limited owing to the rarity of the disease and the paucity of biologically relevant substrates. We conducted the first high-throughput screen (HTS) on a human patient-derived CPC cell line (Children Cancer Hospital Egypt, CCHE-45) and identified 427 top hits highlighting key molecular targets in CPC. Furthermore, a combination screen with a wide variety of targets revealed multiple synergistic combinations that may pave the way for novel therapeutical strategies against CPC. Based on in vitro efficiency, central nervous system (CNS) penetrance ability and feasible translational potential, two combinations using a DNA alkylating or topoisomerase inhibitors in combination with an ataxia telangiectasia mutated and rad3 (ATR) inhibitor (topotecan/elimusertib and melphalan/elimusertib respectively) were validated in vitro and in vivo. Pharmacokinetic assays established increased brain penetrance with intra-arterial (IA) delivery over intra-venous (IV) delivery and demonstrated a higher CNS penetrance for the combination melphalan/elimusertib. The mechanisms of synergistic activity for melphalan/elimusertib were assessed through transcriptome analyses and showed dysregulation of key oncogenic pathways (e.g. MYC, mammalian target of rapamycin mTOR, p53) and activation of critical biological processes (e.g. DNA repair, apoptosis, hypoxia, interferon gamma). Importantly, IA administration of melphalan combined with elimusertib led to a significant increase in survival in a CPC genetic mouse model. In conclusion, this study is, to the best of our knowledge, the first that identifies multiple promising combinatorial therapeutics for CPC and emphasizes the potential of IA delivery for the treatment of CPC.

Final results of the Choroid Plexus Tumor study CPT-SIOP-2000.

INTRODUCTION: Standards for chemotherapy against choroid plexus tumors (CPT) have not yet been established. METHODS: CPT-SIOP-2000 (NCT00500890) was an international registry for all CPT nesting a chemotherapy randomization for high-risk CPT with Carboplatin/Etoposide/Vincristine (CarbEV) versus Cyclophosphamide/Etoposide/Vincristine (CycEV). Patients older than three years were recommended to receive irradiation: focal fields for non-metastatic CPC, incompletely resected atypical choroid plexus papilloma (APP) or metastatic choroid plexus papilloma (CPP); craniospinal fields for metastatic CPC/APP and non-responsive CPC. High risk was defined as choroid plexus carcinoma (CPC), incompletely resected APP, and all metastatic CPT. From 2000 until 2010, 158 CPT patients from 23 countries were enrolled. RESULTS: For randomized CPC, the 5/10 year progression free survival (PFS) of patients on CarbEV (n = 20) were 62%/47%, respectively, compared to 27%/18%, on CycEV (n = 15), (intention-to-treat, HR 2.6, p = 0.032). Within the registry, histological grading was the most influential prognostic factor: for CPP (n = 55) the 5/10 year overall survival (OS) and the event free survival (EFS) probabilities were 100%/97% and 92%/92%, respectively; for APP (n = 49) 96%/96% and 76%/76%, respectively; and for CPC (n = 54) 65%/51% and 41%/39%, respectively. Without irradiation, 12 out of 33 patients with CPC younger than three years were alive for a median of 8.52 years. Extent of surgery and metastases were not independent prognosticators. CONCLUSIONS: Chemotherapy for Choroid Plexus Carcinoma is feasible and effective. CarbEV is superior to CycEV. A subset of CPC can be cured without irradiation.

Delayed Granulocyte Colony-Stimulating Factor (G-CSF) Administration after Chemotherapy Reduces Total G-CSF Doses without Affecting Neutrophil Recovery in a Randomized Clinical Study in Children with Solid Tumors.

The use of G-CSF after myelotoxic chemotherapy accelerates neutrophil recovery reducing the risk of febrile neutropenia. Current guidelines recommend initiating G-CSF 24 hours after myelotoxic chemotherapy. However, the optimal timing of post-chemotherapy G-CSF administration has not been elucidated. Our previous work in murine models demonstrated that the reappearance of myeloid progenitors does not occur in bone marrow until 3-4 days after completion of chemotherapy suggesting that delayed G-CSF administration may be equally efficacious compared to current practice. We conducted a prospective, randomized, crossover study to compare the absolute neutrophil count (ANC) recovery after chemotherapy and a delayed G-CSF administration to a standard G-CSF administration schedule with early G-CSF start. A total of 21 children with solid tumors who received 2 identical cycles of myelotoxic chemotherapy were randomized to start receiving G-CSF either 24 hours after completion of chemotherapy or on the day that their ANC dropped below 1,000/mm3. There was no significant difference in the time to neutrophil recovery (ANC > 1,000/mm3 post nadir) between the two G-CSF administration schedules: 16.0 ± 0.5 days in the standard group compared to 16.7 ± 0.4 days in the delayed group (p = 0.36). The total number of G-CSF doses given, however, was significantly less in the delayed group: 6.7 ± 0.6 compared to 10.5 ± 0.6 doses in the standard group (p < 0.0001). Our data show that a delayed administration of post chemotherapy G-CSF resulted in a significant reduction in the number of G-CSF injections without compromising the G-CSF effects on neutrophil recovery.

Structure-based design generated novel hydroxamic acid based preferential HDAC6 lead inhibitor with on-target cytotoxic activity against primary choroid plexus carcinoma.

Histone deacetylase 6 (HDAC6) is an attractive target for cancer therapeutic intervention. Selective HDAC6 inhibitors is important to minimise the side effects of pan inhibition. Thus, new class of hydroxamic acid-based derivatives were designed on structural basis to perform preferential activity against HDAC6 targeting solid tumours. Interestingly, 1-benzylbenzimidazole-2-thio-N-hydroxybutanamide 10a showed impressive preference with submicromolar potency against HDAC6 (IC50 = 510 nM). 10a showed cytotoxic activity with interesting profile against CCHE-45 at (IC50 = 112.76 µM) when compared to standard inhibitor Tubacin (IC50 = 20 µM). Western blot analysis of acetylated-α-tubulin verified the HDAC6 inhibiting activity of 10a. Moreover, the insignificant difference in acetylated-α-tubulin induced by 10a and Tubacin implied the on-target cytotoxic activity of 10a. Docking of 10a in the binding site of HDAC6 attributed the activity of 10a to π-π stacking with the amino acids of the hydrophobic channel of HDAC6 and capture of zinc metal in bidentate fashion. The therapeutic usefulness besides the on-target activity may define 10a as an interesting safe-lead inhibitor for future development.

Myc and Loss of p53 Cooperate to Drive Formation of Choroid Plexus Carcinoma.

Choroid plexus carcinoma (CPC) is a rare brain tumor that occurs most commonly in very young children and has a dismal prognosis despite intensive therapy. Improved outcomes for patients with CPC depend on a deeper understanding of the mechanisms underlying the disease. Here we developed transgenic models of CPCs by activating the Myc oncogene and deleting the Trp53 tumor suppressor gene in murine neural stem cells or progenitors. Murine CPC resembled their human counterparts at a histologic level, and like the hypodiploid subset of human CPC, exhibited multiple whole-chromosome losses, particularly of chromosomes 8, 12, and 19. Analysis of murine and human CPC gene expression profiles and copy number changes revealed altered expression of genes involved in cell cycle, DNA damage response, and cilium function. High-throughput drug screening identified small molecule inhibitors that decreased the viability of CPC. These models will be valuable tools for understanding the biology of choroid plexus tumors and for testing novel approaches to therapy. SIGNIFICANCE: This study describes new mouse models of choroid plexus carcinoma and uses them to investigate the biology and therapeutic responsiveness of this highly malignant pediatric brain tumor.

Neoadjuvant chemotherapy reduces blood loss during the resection of pediatric choroid plexus carcinomas.

OBJECT Choroid plexus carcinomas (CPCs) are rare brain tumors originating from the ventricular choroid plexus. They account for 2%-4% of all pediatric brain tumors and are most frequently seen in very young children. This pediatric proclivity, in combination with a marked vascularity, renders an aggressive resection a difficult and often dangerous endeavor. Blood losses of several total blood volumes in small children are not uncommon, sometimes forcing the neurosurgeon to abort the procedure, often leaving residual tumor. Great extent of tumor resection is an accepted beneficial factor for overall survival. Therefore, a second resection usually follows the administration of adjuvant chemotherapy. Second-look surgery appears to be associated with markedly decreased blood loss. Histological examination of specimens obtained at a second intervention shows decreased vascularity and fibrotic changes in tumor tissue. At the Hospital for Sick Children in Toronto, this empirical finding led to the strategy of neoadjuvant chemotherapy to minimize blood loss and maximize cytoreduction. The authors undertook this study to assess the potentially beneficial effect of neoadjuvant chemotherapy on blood loss during surgery for CPCs. METHODS In this retrospective cohort review, the demographic, clinical, and treatment parameters of 22 consecutive patients diagnosed with CPC are presented. All underwent surgical treatment at the Hospital for Sick Children from 1982 to 2013. Special attention was given to the impact of neoadjuvant chemotherapy on extent of resection and intraoperative blood loss. Extent of resection was calculated based on perioperative neuroimaging, and amount of blood loss was estimated based on transfusion parameters and perioperative changes in hematocrit. RESULTS Ten patients did not receive neoadjuvant chemotherapy, and 12 were treated with 2-5 cycles of ICE (ifosfamide, carboplatin, etoposide) chemotherapy in a neoadjuvant fashion. The 22 patients included in the study underwent a total of 37 tumor resection surgeries. In all of the cases in which neoadjuvant chemotherapy was used, at least a near-total resection (> 95% of tumor volume) was achieved. Patients who underwent gross-total resection had prolonged overall survival. Of the 37 resections, 18 were performed after chemotherapy. Mean blood loss in the neoadjuvant chemotherapy group was 22% of total estimated blood volume as opposed to 96% in patients without preoperative chemotherapy. CONCLUSIONS In children with CPC, the administration of neoadjuvant chemotherapy decreases intraoperative blood loss and increases extent of resection with a significant positive effect on overall survival.

The role of chemotherapy and surgical removal in the treatment of Choroid Plexus carcinomas and atypical papillomas.

INTRODUCTION: We performed a retrospective study on clinical assessment, tumor location, radiological imaging, histopathological characteristics, and therapeutic management of 7 patients affected by choroid plexus carcinoma (CPC) or atypical choroid plexus papilloma (ACPP) who have been observed in the last 12 years. METHODS: Four patients fulfilled the criteria for classification as ACPP and three cases as CPC. The median age of the patients at the diagnosis was 42 months (range 3-190 months). Except one older patient (15 years old), all patients were younger than 3 years of age. In all patients affected by ACPP, a total surgical resection was achieved. Two children relapsed 12 and 8 months following radical removal. Both of them underwent adjuvant chemotherapy (carboplatin, cyclophosphamide, etoposide, doxorubicin, and methotrexate); a complete remission was maintained in all cases. In all three patients with CPC, it was impossible to achieve complete resection at first surgery. The response to chemotherapy was variable: in one case, it was complete with complete remission following 6 months; in one case, it was partial with reduction on volume (the patient underwent second-look surgery with complete resection); in the third case, there was no response and the patient progressed and finally died with metastatic disease, 8 months after chemotherapy was started. For children with CPC, the OS was 75% at 6 years. RESULTS: In our series, surgery associated with chemotherapy led to long-term survival in 4/4 patients affected by ACPP and 2/3 patients affected by CPC. Clinical results achieved in our series confirm that our therapeutic regimen is feasible and efficient as a possible adjuvant treatment for both CPC and ACPP. It also suggests that surgery has a pivotal role in the management of most children affected by CPTs.

Neoadjuvant chemotherapy for brain tumors in infants and young children.

OBJECT: Because of their large size and high vascularity, complete removal of brain tumors in infants and young children is often difficult. In most cases the degree of resection is associated with prognosis. Neoadjuvant chemotherapy may facilitate resection by reducing the vascularity of the tumor. The authors evaluated the effectiveness of neoadjuvant chemotherapy in the management of these tumors. METHODS: The authors performed a retrospective review of infants and young children who underwent tumor removal after neoadjuvant chemotherapy. RESULTS: Nine consecutive patients underwent resection after neoadjuvant chemotherapy during the period February 2004 to December 2012. The mean age at diagnosis was 18 months (range 2-50 months). The average largest tumor diameter was 71 mm (range 30-130 mm) at initial surgery. Five patients underwent partial resection, and 4 underwent biopsy as the initial surgery. The histopathological diagnoses were ependymoma in 2 patients, anaplastic ependymoma in 1, primitive neuroectodermal tumor (PNET) in 2, choroid plexus carcinoma in 1, atypical teratoid/rhabdoid tumor (AT/RT) in 1, glioblastoma in 1, and embryonal tumor with abundant neuropil and true rosettes in 1. After 2-4 courses of multiagent chemotherapy (mainly with vincristine, cyclophosphamide, etoposide, and cisplatin), the second-look surgery was performed. In 1 patient with a PNET, intratumoral hemorrhage was observed after 2 courses of chemotherapy. The mean interval between the initial and the second-look surgery was 3 months. The tumor volume was reduced to varying degrees in 5 patients (56%) after chemotherapy. Intraoperatively, the vascularity of the tumor was considerably reduced, and the tumor was more circumscribed in all cases. Gross-total resection was achieved in 8 patients (89%) and neartotal resection in 1 (11%). Histopathological examination demonstrated fibrotic tissue circumscribing the tumor in 6 of 9 cases (67%). The average blood loss was 20% of the estimated blood volume, and 3 patients (33%) required a blood transfusion. There was no surgical mortality. One patient had transient dysphasia postoperatively. The mean follow-up period was 28 months. At the last follow-up, 2 patients (22%) had died (1 died of tumor progression and 1 of sepsis), and 4 patients (44%) had no tumor recurrence. CONCLUSIONS: Neoadjuvant chemotherapy for brain tumors in infants and young children was effective in reduction of tumor vascularity and clarification of the tumor-brain interface, which significantly facilitated maximal tumor resection.

Clinical outcome of adult choroid plexus tumors: retrospective analysis of a single institute.

BACKGROUND: Choroid plexus tumors are rare brain tumors with clinical features that vary according to the histological grade. We reviewed the treatment outcomes of 15 adult patients with choroid plexus tumors, focusing on surgical outcomes and current therapeutic strategies. METHOD: Patient demographic and clinical characteristics, operative findings, adjuvant therapies, disease progression and survival rates were reviewed. RESULTS: The median age at diagnosis was 33.7 ± 10 years (19-59 years) for patients with choroid plexus tumors. Postoperative chemotherapy was given to 26.7 % of patients, and 13.3 % of patients received radiotherapy. The Ki-67 labeling index and mitotic index increased at higher histological grades. All of the choroid plexus papilloma and atypical choroid plexus papilloma patients have survived. The overall survival rate of patients with choroid plexus carcinoma was 50 % in the first year, but none of the patients survived to the second year. Five patients underwent permanent cerebrospinal fluid diversion surgery because of hydrocephalus or subdural effusion. CONCLUSIONS: Choroid plexus papilloma and atypical choroid plexus papilloma patients can be treated with complete surgical resection. Choroid plexus carcinoma has a poor prognosis, and aggressive multi-modal treatments are generally needed for treatment. Chemotherapy and radiotherapy are important adjuvant therapies for choroid plexus carcinoma. If hydrocephalus and/or subdural effusion occur, permanent cerebrospinal fluid (CSF) diversion should be added to the therapeutic strategy.

[Antiangiogenic treatment of pediatric CNS tumors in Hungary with the Kieran schedule]. / Gyermekkori központi idegrendszeri daganatok érújdonképzõdés-gátló kezelésének magyarországi eredményei a Kieran-sémával.

In Hungary a new oral antiangiogenic treatment was introduced in cases of primary chemoresistant or recurrent pediatric CNS tumors, called Kieran schedule. The early results of this treatment were analyzed. From 2010 at Semmelweis University on individual decisions a daily combined per oral treatment was introduced in pediatric patients with recurrent or progressive CNS tumor (Kieran schedule: thalidomid, celecoxib, etoposid and cyclophosphamid). Efficacy of therapy was analyzed in terms of demographic data, histology, side effects and tolerability in a retrospective manner. From 2010 through 2013, twenty patients were treated with Kieran schedule (medulloblastoma: 3, ependymoma: 5, anaplastic astrocytoma: 2, GBM: 4, plexus choroideus carcinoma: 1, central primitive neuroectodermal tumor: 1, optic glioma: 2, brainstem tumor: 2). Median treatment time and median progression-free survival were 0.60 and 0.61 years, respectively. Based on the preliminary analysis of a limited cohort of patients, the therapy was efficient in those cases of medulloblastoma, ependymoma, high-grade and optic gliomas, where the expected survival time was more than 3 months at start of treatment. Side effects were slight myelosuppresion in terms of previous therapy, 16% transient ischemic attack (TIA)-like episodes. During therapy patients could live their everyday life. Kieran schedule was well-tolerable and efficient with good quality of life in certain cases of pediatric CNS tumors.

Defining and ranking effects of individual agents based on survival times of cancer patients treated with combination chemotherapies.

An important problem in oncology is comparing chemotherapy (chemo) agents in terms of their effects on survival or progression-free survival time. When the goal is to evaluate individual agents, a difficulty commonly encountered with observational data is that many patients receive a chemo combination including two or more agents. Because agents given in combination may interact, quantifying the contribution of each individual agent to the combination's overall effect is problematic. Still, if on average combinations including a particular agent confer longer survival, then that agent may be considered superior to agents whose combinations confer shorter survival. Motivated by this idea, we propose a definition of individual agent effects based on observational survival data from patients treated with many different chemo combinations. We define an individual agent effect as the average of the effects of the chemo combinations that include the agent. Similarly, we define the effect of each pair of agents as the average of the effects of the combinations including the pair. Under a Bayesian regression model for survival time in which the chemo combination effects follow a hierarchical structure, these definitions are used as a basis for estimating the posterior effects and ranks of the individual agents, and of all pairs of agents. The methods are illustrated by a data set arising from 224 pediatric brain tumor patients treated with over 27 different chemo combinations involving seven chemo agents.

MGMT promoter methylation and temozolomide response in choroid plexus carcinoma.

Choroid plexus carcinoma (CPC) is a malignant tumor with a strong tendency to spread along the cerebrospinal fluid pathway. There is no standardized chemotherapy protocol for this rare tumor. We report a 38-year-old man with CPC in the lateral ventricle with obstructive hydrocephalus. Because of the poor demarcation between thalamus and fornix, subtotal tumor resection was performed. Postoperative spine magnetic resonance (MR) image revealed whole spinal axis dissemination. After diagnosis of CPC, the patient was treated with whole ventricular and spine radiation concomitant with temozolomide chemotherapy, although the O(6)-methylguanine-DNA methyltransferase (MGMT) promoter was found to be unmethylated. Although MR images revealed transient stable disease during adjuvant therapy, tumor progression was depicted after four cycles of temozolomide therapy. We discuss the ineffectiveness of adjuvant temozolomide therapy for CPC in connection with O(6)-methylguanine-DNA methyltransferase promoter methylation.

Use of ifosfamide, carboplatin, and etoposide chemotherapy in choroid plexus carcinoma.

OBJECT: Choroid plexus carcinomas (CPCs) are rare pediatric tumors with a generally poor prognosis. Although the role of surgery is well recognized, the role of adjuvant chemotherapy and radiation therapy remains unclear. In this paper, the authors' goal was to assess the role of second-look surgery and neoadjuvant ifosfamide, carboplatin, etoposide (ICE) chemotherapy in the management of CPC and to study neurocognitive outcome. METHODS: The authors performed an institutional retrospective review of patients in whom CPC was diagnosed between 1985 and 2006 at the Hospital for Sick Children in Toronto. Fourteen patients (7 boys and 7 girls) were included. The median age at diagnosis was 18.6 months (range 1.1-65.3 months). Four patients had evidence of metastatic disease at diagnosis. Two of the 14 patients underwent gross-total resection during initial surgery; 12 of the patients received neoadjuvant chemotherapy, 10 of whom underwent second surgery. In total, of 12 patients who received chemotherapy with a curative intent, 11 underwent a greater than 95% resection. Neoadjuvant ICE chemotherapy was given prior to second surgery (median 4 cycles, range 2-5 cycles) and was continued after second resection for a median total of 7 cycles (range 4-16 cycles). RESULTS: No tumor progression was observed during chemotherapy prior to second surgery. Five patients subsequently experienced tumor progression/relapse. At a median follow-up of 6.9 years (range 1.9-18.5 years), 8 patients are alive. None of the survivors received radiation therapy. However, 6 of 8 display significant neurocognitive and/or sensorial deficit. CONCLUSIONS: In this experience, second surgery following neoadjuvant ICE chemotherapy led to a high rate of complete or near-complete resection. Chemotherapy appears to facilitate second-look surgery, in particular through a reduction of intraoperative blood loss. Despite radiation avoidance, the majority of survivors experienced significant neurocognitive impairment.

Invasive pneumococcal disease following treatment for choroid plexus carcinoma.

INTRODUCTION: A 13-month-old child was treated for choroid plexus carcinoma with partial embolisation, complete surgical excision and chemotherapy. The patient's course was complicated by the presence of chronic bilateral subdural collections. CASE REPORT: Four months from completing treatment, the child presented with an empyema in the subdural space caused by Streptococcus pneumoniae subtype 6A. DISCUSSION: The case highlights a number of questions about pneumococcal immunisation after standard chemotherapy. Evidence-based guidelines are required urgently to direct best practice.

Primary postoperative chemotherapy without radiotherapy for treatment of brain tumours other than ependymoma in children under 3 years: results of the first UKCCSG/SIOP CNS 9204 trial.

BACKGROUND: Radiotherapy is an effective adjuvant treatment for brain tumours arising in very young children, but it has the potential to damage the child's developing nervous system at a crucial time - with a resultant reduction in IQ leading to cognitive impairment, associated endocrinopathy and risk of second malignancy. We aimed to assess the role of a primary chemotherapy strategy in avoiding or delaying radiotherapy in children younger than 3 years with malignant brain tumours other than ependymoma, the results of which have already been published. METHODS: Ninety-seven children were enrolled between March 1993 and July 2003 and, following diagnostic review, comprised: medulloblastoma (n=31), astrocytoma (26), choroid plexus carcinoma [CPC] (15), CNS PNET (11), atypical teratoid/rhabdoid tumours [AT/RT] (6) and ineligible (6). Following maximal surgical resection, chemotherapy was delivered every 14 d for 1 year or until disease progression. Radiotherapy was withheld in the absence of progression. FINDINGS: Over all diagnostic groups the cumulative progression rate was 80.9% at 5 years while the corresponding need-for-radiotherapy rate for progression was 54.6%, but both rates varied by tumour type. There was no clear relationship between chemotherapy dose intensity and outcome. Patients with medulloblastoma presented as a high-risk group, 83.9% having residual disease and/or metastases at diagnosis. For these patients, outcome was related to histology. The 5-year OS for desmoplastic/nodular medulloblastoma was 52.9% (95% confidence interval (CI): 27.6-73.0) and for classic medulloblastoma 33.3% (CI: 4.6-67.6); the 5-year EFS were 35.3% (CI: 14.5-57.0) and 33.3% (CI: 4.6-67.6), respectively. All children with large cell or anaplastic variants of medulloblastoma died within 2 years of diagnosis. The 5-year EFS for non-brainstem high-grade gliomas [HGGs] was 13.0% (CI: 2.2-33.4) and the OS was 30.9% (CI: 11.5-52.8). For CPC the 5-year OS was 26.67% (CI: 8.3-49.6) without RT. This treatment strategy was less effective for AT/RT with 3-year OS of 16.7% (CI: 0.8-51.7) and CNS PNET with 1-year OS of 9.1% (CI: 0.5-33.3). INTERPRETATION: The outcome for very young children with brain tumours is dictated by degree of surgical resection and histological tumour type and underlying biology as an indicator of treatment sensitivity. Overall, the median age at radiotherapy was 3 years and radiotherapy was avoided in 45% of patients. Desmoplastic/nodular sub-type of medulloblastoma has a better prognosis than classic histology, despite traditional adverse clinical features of metastatic disease and incomplete surgical resection. A subgroup with HGG and CPC are long-term survivors without RT. This study highlights the differing therapeutic challenges presented by the malignant brain tumours of early childhood, the importance of surgical approaches and the need to explore individualised brain sparing approaches to the range of malignant brain tumours that present in early childhood.

The impact of radiotherapy fields in the treatment of patients with choroid plexus carcinoma.

PURPOSE: To perform a comprehensive literature review and analysis of cases dealing with choroid plexus carcinoma (CPC) to determine the optimal radiotherapy (RT) treatment field. METHODS AND MATERIALS: A PubMed search of English language articles from 1979 to 2008 was performed, yielding 33 articles with 56 patients who had available data regarding RT treatment field. The median age at diagnosis was 2.7 years (range, 1 month-53 years). Of 54 patients with data regarding type of surgery, 21 (38.9%) had complete resection. Chemotherapy was delivered to 27 (48%) as part of initial therapy. The RT treatment volume was the craniospinal axis in 38 (68%), whole brain in 9 (16%), and tumor/tumor bed in 9 (16%). Median follow-up for surviving patients was 40 months. RESULTS: The 5-year overall survival and progression-free survival (PFS) rates were 59.5% and 37.2%, respectively. Complete resection (p = 0.035) and use of craniospinal irradiation (CSI; p = 0.025) were found to positively affect PFS. The 5-year PFS for patients who had CSI vs. whole brain and tumor/tumor bed RT were 44.2% and 15.3%. For the 19 patients who relapsed, 9 (47%) had a recurrence in the RT field, 6 (32%) had a recurrence outside the RT field, and 4 (21%) had a recurrence inside and outside the irradiated field. CONCLUSION: Patients with CPC who received CSI had better PFS compared with those receiving less than CSI. This study supports the use of CSI in the multimodality management of patients with CPC.

De novo germline TP53 mutation presenting with synchronous malignancies of the central nervous system.

We present a case of a 14-year-old male with a germline TP53 mutation who presented with synchronous primitive neuroectodermal tumor and choroid plexus carcinoma. Identification of synchronous brain tumors prompted genetic testing for predisposition to malignancy. Within 5 months of presentation, the child developed widely metastatic alveolar rhabdomyosarcoma. Patient DNA sequencing showed a TP53 allele with a premature stop codon in the oligomerization/nuclear export signal (NES) domain (R342ter). The child's parents, younger brother, paternal grandparents, and maternal grandmother, are without history of malignancy. The patient's brother tested negative for TP53 mutations. This case identifies a rare, de novo, germline TP53 mutation presenting with synchronous CNS malignancies and exhibiting a more fulminant course than typical cases of Li-Fraumeni syndrome.

Atypical choroid plexus papilloma: clinical experience in the CPT-SIOP-2000 study.

Atypical choroid plexus papilloma (APP) represents a novel intermediate-grade subtype of choroid plexus tumor (CPT), the clinical outcome of which has not been described yet. We present the first analysis of a group of APP patients enrolled in the ongoing CPT-SIOP-2000 study of CPTs. A worldwide registration and a randomized trial for those patients who require chemotherapy started in 2000. For APP, maximal surgical resection was recommended. After surgery, patients who had undergone complete resection were observed, whereas patients with incompletely resected or metastasized APP were treated with six chemotherapy courses (etoposide and vincristine, combined with either carboplatin or cyclophosphamide). Risk-adapted radiotherapy was given only to patients older than 3 years of age. Of the 106 patients with a centrally confirmed CPT histology, 30 had APP, 42 CPP and 34 CPC. APP patients were significantly younger (median = 0.7 years) than patients with CPP or CPC (both medians = 2.3 years). Complete resection was achieved in 68 (64%) patients (79% in CPP, 63% in APP, and 47% in CPC). Metastases were present at diagnosis in 17% of APP patients, 5% of CPP patients, and 21% of CPC patients. All nine APP patients who received postoperative chemotherapy showed an early response after two cycles: two had complete remission, four had partial response, and three had stable disease. In the observation group of 15 patients, one event was seen, and all patients were alive. In the treatment group, one patient with a metastasized tumor and incompletely resected APP died. While APP was defined histologically, median percentages of both the Ki-67/MIB-1 proliferation marker and the p53 tumor suppressor protein increased across the three histological subtypes (from CPP to APP and then CPC), suggesting that the subtypes comprise an ordinal categorization of increasingly severe CPT tumors. This ordering was reiterated by clinical outcome in the 92 patients treated per the study protocol, with 5-year EFS rates of 92% in 39 CPP patients, 83% in 24 APP patients, and 28% in 29 CPC patients. A similar ordering was seen when all 106 patients were evaluated for EFS. APP responded favorably to chemotherapy. The intermediate position of APP between CPP and CPC was supported by the clinical data.