Systemic metastasis of medulloblastoma through ventriculoperitoneal shunt: report of a case and critical analysis of the literature

Peritoneal metastasis of a cerebellar medulloblastoma through a ventriculoperitoneal shunt: A case report

Medulloblastoma is a frequent and aggressive pediatric tumor. It causes intracranial hypertension, necessitating ventriculoperitoneal shunting with surgical resection. Intraperitoneal metastases are rare and result from the migration of neoplastic cells through the shunt and into the peritoneal cavity. This metastatic form involving the ventriculoperitoneal shunt has a poor prognosis, making therapeutic management even more difficult. We report the case of a 14-year-old boy with a history of medulloblastoma of the cerebellum who was initially treated with complete resection of the tumor with placement of a ventriculoperitoneal shunt, followed by radiotherapy and chemotherapy, with good progression until he presented to the emergency department with acute abdominal symptoms. Imaging revealed multiple peritoneal masses with intra- and retroperitoneal lymphadenopathies. An ultrasound-guided biopsy revealed a metastatic medulloblastoma in the peritoneal cavity, and the patient underwent chemotherapy. The placement of the ventriculoperitoneal shunt in the tumor dissemination is therefore to blame.

Predictive factors for persistent postoperative hydrocephalus in children undergoing surgical resection of periventricular tumors

Objective

The aim of this study is to identify the factors predicting persistent hydrocephalus after periventricular tumor resection in children and assess the need and efficacy of perioperative cerebrospinal fluid (CSF) intervention.

Methods

We performed a retrospective analysis of pediatric patients who underwent resection surgery of a periventricular tumor between March 2012 and July 2021 at the Department of Neurosurgery in Zhujiang Hospital of South Medical University. Demographic, radiographic, perioperative, and dispositional data were analyzed using univariate and multivariate models.

Results

A total of 117 patients were enrolled in our study. Incidence of postoperative persistent hydrocephalus varied with tumor pathology (p = 0.041), tumor location (p = 0.046), surgical approach (p = 0.013), extension of resection (p = 0.043), tumor volume (p = 0.041), preoperative Evan's index (p = 0.002), and preoperative CSF diversion (p = 0.024). On logistic regression, posterior median approach (OR = 5.315), partial resection (OR = 20.984), volume > 90cm³ (OR = 5.768), and no preoperative CSF diversion (OR = 3.661) were independent predictors of postoperative persistent hydrocephalus. Preoperative Evan's index is significantly correlated with tumor volume (p = 0.019). Meanwhile, the need for preoperative CSF drainage in patients in this cohort was significantly correlated with tumor location (p = 0.019).

Conclusion

Tumor pathology, location, surgical approach, the extension of resection, tumor volume, preoperative Evan's index, and preoperative CSF diversion were considered to be predictive factors for postoperative persistent hydrocephalus. Notably, posterior median approach, partial resection, and tumor volume > 90cm³, without preoperative CSF diversion, were identified as independent risk factors for persistent postoperative hydrocephalus. Preoperative identification of children at risk of developing persistent postoperative hydrocephalus would avoid delays in planning the cerebrospinal fluid diversion. Active and effective preoperative hydrocephalus intervention in children with periventricular tumors is beneficial to reduce the incidence of persistent hydrocephalus and ventriculoperitoneal shunt surgery after resection.

The evolving role of neurosurgery for central nervous system metastases in the era of personalized cancer therapy

Recent therapeutic advances involving the use of systemic targeted treatments and immunotherapeutic agents in patients with advanced cancers have translated into improved survival rates. Despite the emergence of such promising pharmacological therapies and extended survival, the frequency of metastases in the central nervous system has steadily increased. Effective medical and surgical therapies are available for many patients with brain metastases and need to be incorporated into multi-disciplinary care protocols. The role of neurosurgeons is evolving within these multi-disciplinary care teams. Surgical resection of brain metastases can provide immediate relief from neurological symptoms due to large lesions and provides the histopathological diagnosis in cases of no known primary malignancy. In situations where immunotherapy is part of the oncological treatment plan, surgery may be proposed for expeditious relief of edema to remove the need for steroids. In patients with multiple brain metastases and mixed response to therapeutics or radiosurgery, tumour resampling allows tissue analysis for druggable targets or to distinguish radiation effects from progression. Ventriculo-peritoneal shunting may improve quality of life in patients with hydrocephalus associated with leptomeningeal tumour dissemination and may allow for time to administer more therapy thus prolonging overall survival. Addressing the limited efficacy of many oncological drugs for brain metastases due to insufficient blood-brain barrier penetrance, clinical trial protocols in which surgical specimens are analysed after pre-surgical administration of therapeutics offer pharmacodynamic insights. Comprehensive neurosurgical assessment remains an integral element of multi-disciplinary oncological care of patients with brain metastases and is integral to tumour biology research and therapeutic advancement.

Medulloblastoma in adults - reviewing the literature from a surgeon's point of view

Medulloblastoma is a common primary brain tumor in children but it is a rare cancer in adult patients. We reviewed the literature, searching PubMed for articles on this rare tumor entity, with a focus on tumor biology, advanced neurosurgical opportunities for safe tumor resection, and multimodal treatment options. Adult medulloblastoma occurs at a rate of 0.6 per one million people per year. There is a slight disparity between male and female patients, and patients with a fair skin tone are more likely to have a medulloblastoma. Patients present with cerebellar signs and signs of elevated intracranial pressure. Diagnostic efforts should consist of cerebral MRI and MRI of the spinal axis. Cerebrospinal fluid should be investigated to look for tumor dissemination. Medulloblastoma tumors can be classified as classic, desmoplastic, anaplastic, and large cell, according to the WHO tumor classification. Molecular subgroups include WNT, SHH, group 3, and group 4 tumors. Further molecular analyses suggest that there are several subgroups within the four existing subgroups, with significant differences in patient age, frequency of metastatic spread, and patient survival. As molecular markers have started to play an increasing role in determining treatment strategies and prognosis, their importance has increased rapidly. Treatment options include microsurgical tumor resection and radiotherapy and, in addition, chemotherapy that respects the tumor biology of individual patients offers targeted therapeutic approaches. For neurosurgeons, intraoperative imaging and tumor fluorescence may improve resection rates. Disseminated disease, residual tumor after surgery, lower radiation dose, and low Karnofsky performance status are all suggestive of a poor outcome. Extraneural spread occurs only in very few cases. The reported 5-year-survival rates range between 60% and 80% for all adult medulloblastoma patients.

Spreading of struma ovarii tumour via a lumbo-peritoneal shunt: first case report and short review of the literature

Neurosurgical shunts occasionally act as a conduit for seeding of central nervous system tumours to the abdomen. Retrograde spread of extra-neural tumours to the central nervous system is exceedingly rare. We report the first case of an abdominal primary tumour spreading to the spinal cord via a lumbo-peritoneal shunt. This is also the first case report of a struma ovarii tumour metastasis to the central nervous system via any route.

A brainstem mass of Müllerian type Epithelial Origin without any primary cancer source

Brainstem tumors are rare, even rarer is a brainstem tumor containing tissues of an embryologic gynecologic origin. We report a very rare case of presence of a calcified heterogeneously contrast enhancing brainstem mass of Müllerian origin in a patient in a 38 year old female with no female genital tract cancer and past surgical history of ventriculoperitoneal (VP) shunt placement for congenital hydrocephalus. To our knowledge this is the very first and unusual case of a mass of gynecologic origin in the brainstem region especially in the setting of no history of gynecological tumor. The authors also reviewed the literature for all tumors reported for anterograde and retrograde dissemination of tumor cells through VP shunt. This case is a reaffirmation of the importance of brain tumor location and tissue diagnosis for the purpose of adjuvant treatment of neurosurgical lesions in the neurocritical care setting. It also highlights the role of catheters as potential routes of iatrogenic transmission not just in anterograde but also in a retrograde manner to the CNS, which is very unusual. This is the only second case to report retrograde flow of tumor cells from an extraneural source up the VP catheters. The authors suggest that intraperitoneal chemotherapy should be considered in the cases of known extraneural abdominal malignancies of high malignant potential with or without the presence of peritoneal infiltration in order to avoid dissemination through VP shunts.

Widespread Intra-abdominal Carcinomatosis from a Rhabdoid Meningioma after Placement of a Ventriculoperitoneal Shunt: A Case Report and Review of the Literature

Intra-abdominal metastasis (IAM) of central nervous system (CNS) tumors via ventriculoperitoneal shunt (VPS) is rare but has been previously reported (e.g., germinomas and medulloblastomas). However, there has been no previous report in the literature involving meningiomas. A case of primary rhabdoid meningioma with widespread intra-abdominal carcinomatosis after placement of a VPS in a 36-year-old man is described. The patient underwent preoperative angioembolization of the tumor, craniotomy, and surgical excision, followed by postoperative gamma knife radiosurgery. Five months later, he underwent a decompressive craniectomy and surgical excision for tumor recurrence causing raised intracranial pressure and communicating hydrocephalus, necessitating placement of a VPS. One month after placement of the VPS, the patient developed abdominal distension and confusion. He was treated for a VPS infection, and the shunt was explanted. He continued to deteriorate with high output from the peritoneal drain placed at the time of shunt explantation. An exploratory laparotomy revealed multiple diffuse peritoneal and omental nodules which had the same histopathological and immunohistochemical morphology as the primary tumor. We reviewed the current literature on IAM of primary CNS tumors via VPS, which revealed that patients belonging in the pediatric age group, of the male gender, and with a primary intracranial germinoma or medulloblastoma have a higher incidence of IAM. Majority of IAM occurred within 2 years of VPS placement, and patients most commonly present with abdominal distension and ascites. Treatment after diagnosis is varied and the prognosis is poor, with more than half of the patients dying within a year. It is vital for clinicians to maintain a high index of suspicion for similar patients, as early intervention could potentially improve patient outcomes and patient expectations managed more effectively.

Widespread Intra-abdominal Carcinomatosis from a Rhabdoid Meningioma after Placement of a Ventriculoperitoneal Shunt: A Case Report and Review of the Literature

Intra-abdominal metastasis (IAM) of central nervous system (CNS) tumors through ventriculoperitoneal shunt (VPS) is rare but has been previously reported (e.g., germinomas and medulloblastomas). However, there has been no previous reports in literature involving meningiomas. A case of primary rhabdoid meningioma with widespread intra-abdominal carcinomatosis after placement of a VPS in a 36-year-old man is described. The patient underwent preoperative angioembolization of the tumor, craniotomy, and surgical excision, followed by postoperative gamma knife radiosurgery. Five months later, he underwent a decompressive craniectomy and surgical excision for tumor recurrence causing raised intracranial pressure and communicating hydrocephalus, necessitating placement of a VPS. One month after placement of the VPS, the patient developed abdominal distension and confusion. He was treated for a VPS infection and the shunt was explanted. He continued to deteriorate with high output from the peritoneal drain placed at the time of shunt explantation. An exploratory laparotomy revealed multiple diffuse peritoneal and omental nodules which had the same histopathological and immunohistochemical morphology as the primary tumor. We reviewed the current literature on IAM of primary CNS tumors through VPS, which revealed that patients belonging to the pediatric age group of the male gender and with a primary intracranial germinoma or medulloblastoma have a higher incidence of IAM. The majority of IAM occurred within 2 years of VPS placement, and patients most commonly present with abdominal distension and ascites. Treatment after diagnosis is varied, and the prognosis is poor, with more than half of the patients dying within a year. It is vital for clinicians to maintain a high index of suspicion for similar patients as early intervention could potentially improve patient outcomes and patient expectations managed more effectively.

Management of hydrocephalus in pediatric metastatic tumors of the posterior fossa at presentation

PURPOSE

Presence of metastases in newly diagnosed pediatric posterior fossa tumors (PFT) is not a rare situation, but optimal treatment of associated hydrocephalus in these children has remained undetermined.

METHODS

Twenty-nine children treated between January 2005 and December 2015 for a metastatic PFT associated with hydrocephalus constituted the study cohort. Patients were divided into three groups: ventriculoperitoneal shunt (VPS), endoscopic third ventriculostomy (ETV), and temporary ventricular drainage before or during tumor resection (PVD).

RESULTS

There were 4 VPS, 18 ETV, and 7 PVD. The global incidence of CSF diversion failure was 52%. No case of dysfunction or dissemination of metastatic cells occurred in the VPS group. Recurrence of hydrocephalus occurred in 55% of the ETV group. Presence of multiple macroscopic metastases and CSF metastatic cells after tumor surgery was associated with ETV failure. Fifty-seven percent of the children in the PVD group were reoperated after an average time of 53 days. Specific oncologic treatment was initiated earlier in the VPS group (11 days) compared to ETV (27 days) and PVD (23 days) groups.

CONCLUSIONS

ETV should be avoided in cases of multiple macroscopic metastases, and children who underwent ETV must be followed carefully when metastatic cells are present in CSF after tumor surgery. External ventricular drainage before or during surgical removal should not be considered as a final option to treat hydrocephalus. VPS remains a safe alternative in this situation and allows an early specific oncologic treatment.

Extracranial, peritoneal seeding of primary malignant brain tumors through ventriculo-peritoneal shunts in children: Case report and review of the literature

INTRODUCTION

Ventriculoperitoneal shunts (VPS) have been implicated as a source of the extraneural spread of a wide variety of central nervous system tumors. The purpose is to review the literature on peritoneal seeding of central nervous system tumors from VPS in the context of a case report.

METHODS

Medline was searched using the phrase 'peritoneal seeding ventriculoperitoneal shunt'. Inclusion criteria included patients (<18 years) with evidence of peritoneal seeding from VPS.

RESULTS

Search of the literature revealed a final total of 22 articles and a total of 28 patients.

CASE REPORT

A 7-year-old boy presented with intermittent vomiting, headaches, photophobia; a 4.4 cm left thalamic mass (glioblastoma multiforme) was found. Occipital VPS catheters were placed for increasing hydrocephalus and the patient developed increased abdominal distention and pain. Computed tomography revealed diffuse ascites with carcinomatosis and the patient was diagnosed clinically with peritoneal metastases.

DISCUSSION

Our case report and literature review revealed 28 cases of central nervous system tumors demonstrating evidence of extraneural spread associated with VPS in children in a wide variety of tumors. Larger studies are required to evaluate VPS as potential risk factors for peritoneal seeding and familiarity with potential VPS-related peritoneal seeding is important for diagnostic consideration.

Management of posterior fossa tumors and hydrocephalus in children: a review

OBJECT

Most pediatric patients that present with a posterior fossa tumor have concurrent hydrocephalus. There is significant debate over the best management strategy of hydrocephalus in this situation. The objectives of this paper were to review the pathophysiology model of posterior fossa tumor hydrocephalus, describe the individual risks factors of persistent hydrocephalus, and discuss the current management options. Specifically, the debate over preresection cerebrospinal fluid diversion is discussed.

RESULTS

Only 10-40 % demonstrate persistent hydrocephalus after posterior fossa tumor resection. It appears that young age, moderate to severe hydrocephalus, transependymal edema, the presence of cerebral metastases, and tumor pathology (medulloblastoma and ependymoma) on presentation predict postresection or persistent hydrocephalus. The Canadian Preoperative Prediction Rule for Hydrocephalus (CPPRH), a validated prediction model, can be used to stratify patients at point of first contact into high and low risk for persistent hydrocephalus.

CONCLUSIONS

A protocol is proposed for managing hydrocephalus that utilizes the CPPRH. Low-risk patients can be monitored conservatively with or without an intraoperative extraventricular drain, while high-risk patients require the use of an intraoperative extraventricular drain, higher postoperative hydrocephalus surveillance, and even consideration for a preoperative endoscopic third ventriculostomy.

Medulloblastoma: seeding of VP shunt tract and peritoneum

We report on a 5-year-old boy with seeding of the peritoneum and a ventriculoperitoneal shunt tract by anaplastic medulloblastoma. The role of ventriculoperitoneal shunting in the spread of primary central nervous system tumors has been controversial. In the case reported here, the unique distribution of tumor implants on ultrasound and multiplanar computed tomography gives further credence to the argument that ventriculoperitoneal shunting is a pathway for extraneural metastases of primary central nervous system tumors.

Medulloblastoma and primitive neuroectodermal tumors

Medulloblastomas and sPNETs remain highly problematic tumors to treat. Prognosis has improved over the past two decades, but many children who survive treatment have significant long-term sequelae. The improvements in outcome have been due to advances in surgical techniques, the wider use of chemotherapy, and the more judicious use of radiotherapy. For further improvements,the recent impressive discoveries concerning molecular mechanisms of embryonal tumor origin, development,and growth will need to be translated into molecularly based, risk-adapted therapy.

Extraneural metastases in medulloblastoma

Medulloblastoma is the most common childhood malignant tumor of central nervous system, but it may also occur in adults. It presents high invasive growth with spreading of tumor cells into the leptomeningeal space along the neuroaxis early in the course of the disease. Extraneural metastases are rare but frequently lethal, occurring only in 1 to 5% of patients, and are related, in the most of cases, to the presence of ventriculoperitoneal shunt. Here we characterize the clinical profile of five cases of medulloblastoma with systemic spreading of tumor cells, also comparing them to cases already described in the literature.

Hydrocephalus Indian scenario - A review

Hydrocephalus is a common clinical problem seen in pediatric neurosurgical practice. Hydrocephalus involves dilatation of the cerebral ventricular system with corresponding, compressive effects on the parenchyma. It can be communicative or obstructive types. Congenital, acquired, infective, and secondary hydrocephalus have different clinical features with different modality of treatments. Ventriculoperitoneal shunt is the gold standard of treatment. Endoscopic 3(rd) ventriculostomy is rapidly gaining prominence as an alternative. Various kinds of hydrocephalus, their pathophysiology, treatment and complications are reviewed.

Shunt-related Abdominal Metastases in a Child with Choroid Plexus Carcinoma: Case Report

OBJECTIVE AND IMPORTANCE

Metastasis of primary brain neoplasms to the abdomen through a ventriculoperitoneal shunt (VPS) has been described for many types of tumors, including medulloblastoma, germ cell tumors, astrocytoma, oligodendroglioma, lymphoma, ependymoma, and melanoma. Choroid plexus tumors (CPTs) are located within the cerebrospinal fluid-containing spaces of the brain and frequently disseminate throughout the craniospinal subarachnoid space, yet VPS-related metastasis of a CPT to the abdomen has not been reported previously.

CLINICAL PRESENTATION

We present the case of a 3-year-old boy with choroid plexus carcinoma of the lateral ventricle and preoperative intraventricular dissemination of the tumor. The patient later developed VPS-related abdominal metastases causing abdominal ascites.

INTERVENTION

Surgical resection of the tumor was followed by chemotherapy and craniospinal radiation, but the tumor further disseminated throughout the craniospinal subarachnoid space. When the child presented with abdominal ascites, the distal VPS catheter was externalized and drained cerebrospinal fluid at a rate of more than 750 ml/d. Paracentesis was performed for persistent ascites, and cytological analysis of the fluid revealed metastatic tumor cells.

CONCLUSION

The child died from widely metastatic tumor and aspiration pneumonia. CPT metastasis to the abdomen through a VPS should be considered in patients with the appropriate clinical findings. This condition may exacerbate overproduction of cerebrospinal fluid, which can occur with CPTs, and treatment must be individualized. Unusual options may be considered, such as long-term shunt externalization or paracentesis.

Review of the prognostic factors in medulloblastoma of children and adults

Medulloblastoma (MB) is rare in adults, accounting for 1% of all primary tumours of the central nervous system (CNS). Based on the assumption that the disease pattern in adults is similar to that in children, adults with medulloblastoma are treated using paediatric protocols. Thanks to progress made in recent years, long-term survival is now possible, with overall ranging from 50 to 60% at 5 years and 40 to 50% at 10 years. However, effective therapy may have devastating long-term side effects, including neuro-psychic and neuro-endocrine sequelae and cognitive dysfunction, especially in young adults. Great interest has been expressed in new biological and molecular prognostic factors, which, combined with clinical variables, may allow a more satisfactory stratification of patients.

Pure subcutaneous seeding from medulloblastoma

The authors present a patient with subcutaneous tumors associated with a desmoplastic medulloblastoma. This 6-year-old male who had previously undergone total removal of a cerebellar medulloblastoma was admitted because of new tumoral masses in the abdominal wall and the nuchal area. Ultrasound imaging demonstrated that both lesions were in the subcutaneous tissue. Both tumors were in the vicinity of the surgical incisions, which implies that they were implanted during previous procedures. Pathologic examination of the tumors obtained from gross surgical resection revealed medulloblastoma but with less advanced differentiation compared with the primary neoplasm. This report discusses unusual pure limited subcutaneous metastases of medulloblastoma. The objective of this report is to bring into consideration this presentation of medulloblastoma to the neurologic differential diagnosis.

Extraneural metastases of paediatric brain tumours

A survey of published cases of extraneural metastases of primary brain tumours in children under the age of 18 years revealed 245 cases; 60.7% occurred in boys and 27.3% were directly related to the placing of a shunt. The most common entities leading to extraneural metastases were medulloblastomas (56.3%), germinomas (9.8%), glioblastomas (6.9%), ependymomas (3.7%) and pilocytic astrocytomas (2.9%). While medulloblastomas were frequent among non-shunt-related metastases (69.4%), germ cell tumours were most common among shunt-related metastases (33.3%). Metastases were encountered equally often in bone (56.3%) and visceral organs (55.5%) but were markedly rarer in lymph nodes (25.3%). Medulloblastomas showed a preference for bones (88.3% of cases), germinomas for bones (77.8%) and visceral organs (66.7%), whereas ependymomas and ependymoblastomas were more frequently found in lymph nodes and visceral organs (71.5-100%). The most frequent sites of bone metastases were the pelvis (59.3% of cases with osseous lesions), femur (54%) and vertebrae (46%). Medulloblastomas preferentially spread into pelvis, femur and vertebrae, whereas germ cell tumours mainly involved pelvis, femur and ribs and glioblastomas vertebrae and pelvis. Most frequent sites of lymph node metastases were cervical (45.8% of cases with nodular lesions) and thoracic (31.3%) with 54% of children suffering from medulloblastomas and 7.9% from germ cell tumours. The most frequent organ involved in non-shunt-related metastases were the lungs (56.5% of children with visceral lesions) followed by muscle/soft tissue (26.9%), pleura (16.4%), skin (14.9%) and liver (13.4%). Among shunt-related cases, the peritoneum was the most frequent site (86.6% of children). The mean interval between primary brain tumour and occurrence of metastasis was 22.1 months with particularly grave outcomes among medulloblastomas, non-germinomatous germ cell tumours and glioblastomas (85.5-100% deceased children), whereas 60% of children suffering from germinomas were still alive at the time of reporting.

Medulloblastomas with systemic metastases: evaluation of tumor histopathology and clinical behavior in 23 patients

PURPOSE

To review the clinical behavior and histopathologic features of medulloblastomas that metastasize outside the central nervous systems (CNS).

PATIENTS AND METHODS

The authors studied 23 cases of medulloblastomas that metastasized outside the CNS. The patients included 15 males and 8 females, ages 1 to 40 years at initial diagnosis (median 8.5). Five of the patients were over 20 years of age at diagnosis. The histologic grade of anaplasia was determined for each case.

RESULTS

Extra-CNS metastases were identified at initial presentation in four individuals and up to 11 years later in the remaining cases. Metastatic sites included bone/bone marrow (21 cases), soft tissue/lymph nodes (3 cases), and lung (1 case). In seven cases, multiple extra-CNS metastatic sites were documented. Of the patients with available clinical follow-up after metastasis, 10 died of their disease 1 to 39 months after detection of extra-CNS metastases (median 9 months), while 5 are alive 16 to 120 months after extra-CNS metastasis (median 45 months). Moderate or severe anaplasia was detected in 8 of 20 intracranial specimens (40%) and in 4 of 6 extra-CNS metastases (66%); these frequencies are higher than observed in medulloblastomas overall. Tissue from both the initial resection and subsequent recurrence or metastasis was available in six cases. The anaplasia grade was higher upon recurrence or metastasis in four of these six, consistent with tumor progression.

CONCLUSIONS

Metastasis of medulloblastomas outside the CNS can occur after long periods of clinical remission and is associated with anaplasia in some cases. Medulloblastomas can show histologic progression on recurrence or metastasis.

Shunt-related abdominal metastases in an infant with medulloblastoma: long-term remission by systemic chemotherapy and surgery

This is the first reported case of long remission of abdominal metastases spread through a ventriculo-peritoneal shunt in an infant diagnosed, four years ago, at age 1 year and 10 months, to have cerebral medulloblastoma. Two years later, while in second complete remission of his cerebral tumor, he showed abdominal metastases, successfully treated by platinum based chemotherapy and surgery. One year later, a second abdominal relapse and hepatic metastases were treated by doxorubicin administration and surgery. Since then the child remained in continuous complete remission. This unusual favorable outcome can be explained by an extreme responsiveness of the tumor, unprotected by the blood brain barrier, to systemic chemotherapy, particularly to doxorubicin administration. The need for careful surveillance of patients with ventriculo-peritoneal shunts is emphasized. Searching for new tools, such as entrapment of doxorubicin in liposomes, able to overcome the blood-brain barrier and to expose brain tumors to effective drugs, probably represents the best choice for future treatment strategies of CNS tumors.

Extracranial metastasis of anaplastic ganglioglioma through a ventriculoperitoneal shunt: a case report

Extracranial metastasis of an intracranial anaplastic ganglioglioma through a ventriculoperitoneal shunt is reported. A 53-year-old woman was treated by surgery, radiation and chemotherapy and died 2 years later. At autopsy, multiple metastatic lesions were found in the spinal cord, and the abdominal and pleural cavities. Histologically, all the metastatic lesions were composed of atypical cells which resembled primitive glial elements found in intracranial anaplastic ganglioglioma, suggesting that anaplastic glial elements have a metastatic potential. Extracranial metastasis of ganglioglioma is a rare occurrence; however, the spread of glial elements through the shunt further suggests that caution is required in therapy and indicates a need for protective filters in the shunt system.

Secondary manifestation of medulloblastoma: metastases and local recurrences in 66 patients

Although primary treatment of medulloblastoma is now successful in a high percentage of patients, its secondary manifestations still bear a poor prognosis. Thorough studies of secondary manifestations are therefore pivotal to plan therapeutic approaches for the long-term management of medulloblastoma. Here we describe the incidence of secondary tumour manifestations in 66 patients of a single centre who underwent surgery for medulloblastoma between 1975 and 1990. No patient was excluded due to a poor postoperative course. Thirty-five patients showed evidence of secondary tumour growth. Of these, 17 suffered from local recurrence, and 27 developed metastastatic disease. The median latencies for secondary manifestations were 25 months for local recurrence (n = 17), 11 months for spinal metastases (n = 10), 15 months for supratentorial metastases (n = 8), 8 months for subleptomeningeal dissemination (n = 6), and 23 months for systemic metastases (n = 8). Two patients developed primary metastatic spread to the posterior fossa. Of 8 patients with supratentorial metastases, 6 developed fronto-basal lesions. In our patients, 89% of secondary lesions occurred within less than 3 years after primary diagnosis. 85% of patients with extra-axial tumour spread had been treated with a permanent shunt. Radical tumour resection and radiotherapy with 30 Gy to the neuraxis and 20 Gy boost to the posterior fossa was an important prognostic factor in this series. Patients with additional chemotherapy did not benefit significantly from this treatment. We conclude that optimal management of the primary lesions should aim at (i) total resection, (ii) avoid permanent shunting, and (iii) completion of the radiotherapy with inclusion of the medial frontobasal cisterns in the radiotherapeutic regimen. Our analysis suggests that adequate postoperative screening programmes should consist of 3-monthly scans of the neuraxis in the first three postoperative years and 6-monthly scans thereafter.