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Published on: October 3, 2010
Primary leptomeningeal primitive neuroectodermal tumor
Martin Begemann1, David Lyden, Marc K Rosenblum
1Department of Neurology, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA. begemanm@mskcc.org
Abstract:
Leptomeningeal metastases are a common complication of medulloblastomas and other primitive neuroectodermal tumors (PNETs). Much rarer are PNETs apparently arising in the leptomeninges. An 8-year-old boy presented with headache and vomiting, due to neoplastic meningitis from primary neuroectodermal tumor without an identifying mass. After craniospinal irradiation and chemotherapy (carboplatin, vincristine, cyclophosphamide and lomustine) the boy was in remission for 14 months, then suffered several relapses despite various chemotherapy regimens. After the initial presentation of 3.5 years the boy began to suffer from prolonged refractory non-convulsive status epilepticus and later expired from progression of primary leptomeningeal PNET.
Insights
Primary leptomeningeal primitive neuroectodermal tumors (PNETs) are rare. This case highlights a challenging PNET presentation in an 8-year-old, demonstrating resistance to standard treatments and eventual disease progression.
Area of Science:
- Neuro-oncology
- Pediatric oncology
- Neurosurgery
Background:
- Leptomeningeal metastases are common in medulloblastomas and other primitive neuroectodermal tumors (PNETs).
- Primary PNETs originating in the leptomeninges are exceptionally rare.
- Early diagnosis and treatment are crucial for managing CNS tumors.
Observation:
- An 8-year-old boy presented with symptoms of neoplastic meningitis, including headache and vomiting.
- The PNET was diagnosed without an identifiable primary mass.
- The patient experienced an initial remission after craniospinal irradiation and chemotherapy.
Findings:
- Despite aggressive treatment with carboplatin, vincristine, cyclophosphamide, and lomustine, the patient suffered multiple relapses.
- The PNET demonstrated resistance to various chemotherapy regimens.
- The patient developed prolonged refractory non-convulsive status epilepticus.
Implications:
- This case underscores the diagnostic and therapeutic challenges posed by primary leptomeningeal PNETs.
- It highlights the need for novel therapeutic strategies for rare and aggressive CNS tumors.
- Further research into the biology and treatment of these rare tumors is warranted.
