Genetics of choroid plexus tumors

Single-nucleus RNA-seq dissection of choroid plexus tumor cell heterogeneity

The genomic, genetic and cellular events regulating the onset, growth and survival of rare, choroid plexus neoplasms remain poorly understood. Here, we examine the heterogeneity of human choroid plexus tumors by single-nucleus transcriptome analysis of 23,906 cells from four disease-free choroid plexus and eleven choroid plexus tumors. The resulting expression atlas profiles cellular and transcriptional diversity, copy number alterations, and cell-cell interaction networks in normal and cancerous choroid plexus. In choroid plexus tumor epithelial cells, we observe transcriptional changes that correlate with genome-wide methylation profiles. We further characterize tumor type-specific stromal microenvironments that include altered macrophage and mesenchymal cell states, as well as changes in extracellular matrix components. This first single-cell dataset resource from such scarce samples should be valuable for divising therapies against these little-studied neoplasms.

Convection-enhanced delivery for the treatment of glioblastoma

Effective treatment of glioblastoma (GBM) remains a formidable challenge. Survival rates remain poor despite decades of clinical trials of conventional and novel, biologically targeted therapeutics. There is considerable evidence that most of these therapeutics do not reach their targets in the brain when administered via conventional routes (intravenous or oral). Hence, direct delivery of therapeutics to the brain and to brain tumors is an active area of investigation. One of these techniques, convection-enhanced delivery (CED), involves the implantation of catheters through which conventional and novel therapeutic formulations can be delivered using continuous, low-positive-pressure bulk flow. Investigation in preclinical and clinical settings has demonstrated that CED can produce effective delivery of therapeutics to substantial volumes of brain and brain tumor. However, limitations in catheter technology and imaging of delivery have prevented this technique from being reliable and reproducible, and the only completed phase III study in GBM did not show a survival benefit for patients treated with an investigational therapeutic delivered via CED. Further development of CED is ongoing, with novel catheter designs and imaging approaches that may allow CED to become a more effective therapeutic delivery technique.

Brain tumors of infancy--an institutional experience and review of the literature

INTRODUCTION

Brain tumors in infants are rare and form a distinct subgroup of pediatric brain tumors. These tumors differ from tumors in older children with respect to histology and management and tend to have a poorer outcome.

METHODS

We analyzed 31 consecutive cases of brain tumors in infancy managed in our institute in the last 15 years and reviewed the published literature since 1990.

RESULTS

Only 2 of these patients had congenital tumors. Choroid plexus tumors were the most common histological subtype, followed by medulloblastoma; 62% of patients underwent a gross total or near-total excision of the tumor with 1 perioperative mortality; 68% of patients had a good outcome.

CONCLUSION

Choroid plexus tumors were the most common histological type. Safe resection should be the goal of surgery. Surgeries for tumors in this age group were associated with lower rates of total excision and higher morbidity. Low-grade lesions as expected are associated with longer survival; however, long-term outcomes are far from satisfactory.

Prenatal diagnosis and successful postnatal therapy of an atypical choroid plexus papilloma-Case report and review of literature

This report describes the perinatal management of a prenatally detected choroid plexus papilloma in an otherwise unaltered singleton pregnancy of a healthy woman. After elective Caesarean section, a successful embolization of the feeding vessel followed by a craniotomy and complete removal of the remaining tumor were performed. Histological examination confirmed the diagnosis. One-, 2-, and 3-year follow-up showed a normal development of the girl with a regular neuropediatric status. A review of literature including related papers listed in PubMed between 1985 and 2009 are included.

Choroid plexus carcinoma

Choroid plexus carcinoma is an uncommon neoplasm of the central nervous system most commonly found in the pediatric population. It is associated with a dismal prognosis, especially if incompletely resected. Accurate histopathologic diagnosis is imperative, and this neoplasm should always be included in the differential diagnosis of a papillary intraventricular tumor. Histopathologic features include blurring of papillary architecture, layers of neoplastic choroid plexus epithelial cells with pleomorphic nuclei, increased nuclear-to-cytoplasmic ratio, increased mitotic activity, areas of necrosis, and brain invasion. Current accepted treatment is gross total surgical resection of the tumor as the goal. Use of adjuvant chemotherapy is controversial at this time; however, it is considered in some cases.

Metastasis of a histologically benign choroid plexus papilloma: case report and review of the literature

Cerebrospinal metastases of benign choroid plexus papillomas (CPPs) are extremely rare. We report a case of 32-year-old woman who presented with a 6-month history of vertigo and intermittent headache. Plain CT scan of the cranium revealed a partly calcified tumor filling the fourth ventricle and its right recess. Cranial MRI showed an inhomogeneously contrast-enhancing tumor and leptomeningeal enhancement encasing the brain stem. Complete resection of the tumor was carried out, and seedings to the floor of the fourth ventricle and cervico-medullary junction were found during the operation. While intraoperative frozen section suggested pathology of papillary ependymoma or CPP, to our surprise, final histological examination revealed a benign choroid plexus papilloma. One month after the first operation, a metastatic nodule was found in the spinal subarachnoidal space at the level of T8-9. Two months after the first operation, on follow-up MRI of the cranium, the leptomeningeal enhancement encasing the brain stem had resolved spontaneously. This special case helps increase our understanding of benign CPPs and expands our differential diagnostic consideration of lesions with similar manifestations.