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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Most common cause of leptomeningeal spread is from which of the following
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The correct answer is  Leptomeningeal metastases, also know as carcinomatous meningitis, refers to the spread of malignant cells through the CSF space. These cells can originate from primary CNS tumors (e.g. This aicle has a focus on subarachnoid space involvement. Refer to <a class="internal" style="box-sizing: border-box; background: transparent; color: ; text-decoration-line: none;" href=" extramedullary metastases</a> for a discussion of leptomeningeal metastases in the spine. For other intracranial metastatic locations, please refer to the main aicle on <a class="internal" style="box-sizing: border-box; background: transparent; color: ; text-decoration-line: none;" href=" metastases</a>.