skip to main content

Leptomeningeal Carcinomatosis — SCE Neurology MCQ

Instant feedback + full explanation. One question, done properly.

HardNeuro-oncologyLeptomeningeal CarcinomatosisSCE Neurology

A patient with metastatic breast cancer develops multiple cranial neuropathies and cauda-equina pain. Gadolinium MRI shows linear leptomeningeal enhancement. Initial CSF cytology is negative, but only 2 mL was sent after a traumatic tap and processing took 3 hours. What is the best next diagnostic step?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Repeat one lumbar puncture, obtain ideally more than 10 mL, avoid blood contamination and process within 30 minutes

Explanation lettering: D = shown as A · E = shown as B · B = shown as D · A = shown as E

A is correct: the first sample was collected under conditions that markedly reduce sensitivity; EANO–ESMO recommends one repeat under optimised conditions, ideally more than 10 mL and rapid processing. B undercalls a compelling syndrome. C is not yet a validated replacement for CSF cytology. D adds procedural burden after the yield of further samples becomes doubtful. E omits gadolinium and cannot settle the cytological question.

Reference: EANO–ESMO guideline: leptomeningeal metastasis from solid tumours: https://pmc.ncbi.nlm.nih.gov/articles/PMC10619142/