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Band-Like Brainstem Lesion in a Patient With a History of Lung Adenocarcinoma
1Neurology, National Hospital Organization Akita National Hospital, Yurihonjo, JPN.
Abstract:
Leptomeningeal metastasis (LM) is a severe complication of primary malignancy that has spread to the leptomeninges and cerebrospinal fluid (CSF). Here, we report a patient whose magnetic resonance imaging (MRI) showed a unique brainstem lesion suspicious of LM. A 72-year-old man presented with dizziness, gait instability, and cognitive decline, primarily object naming. He had a history of lung adenocarcinoma with epidermal growth factor receptor (EGFR) mutation. Brain MRI revealed a band-like lesion surrounding the ventral brainstem with T2 weighted-image/fluid attenuation inversion recovery (FLAIR) imaging and diffusion-weighted imaging (DWI) hyperintensity without gadolinium enhancement. No malignant cells were detected in the CSF. He underwent ventriculoperitoneal shunt two months after the onset, and his gait improved, but his cognitive function declined further. Recent reports suggest similar brainstem lesions as a unique LM pattern, which occurs almost exclusively in patients with lung adenocarcinoma with EGFR mutation. Therefore, if MRI shows this brainstem finding, repeated and appropriate CSF cytology is needed to detect tumor cells. Furthermore, if a patient with lung adenocarcinoma shows a cognitive decline, cerebral LM and auto-antibodies that mainly target neuronal surface antigens should be considered.
Insights
Leptomeningeal metastasis (LM) can present as a unique brainstem lesion in EGFR-mutated lung adenocarcinoma. Early detection through MRI and cerebrospinal fluid analysis is crucial for managing this severe complication.
Area of Science:
- Neuro-oncology
- Radiology
Background:
- Leptomeningeal metastasis (LM) is a severe complication of cancer spread to the meninges and cerebrospinal fluid (CSF).
- Lung adenocarcinoma with epidermal growth factor receptor (EGFR) mutations is increasingly recognized for unique metastatic patterns.
Observation:
- A 72-year-old man with EGFR-mutated lung adenocarcinoma presented with neurological symptoms including dizziness and cognitive decline.
- Brain magnetic resonance imaging (MRI) revealed a distinctive band-like lesion around the ventral brainstem, showing specific signal characteristics on T2/FLAIR and DWI sequences without enhancement.
Findings:
- Despite initial negative cerebrospinal fluid (CSF) cytology, the unique MRI findings suggested leptomeningeal metastasis.
- The patient underwent a ventriculoperitoneal shunt, which improved gait but not cognitive decline, highlighting the complexity of managing brainstem LM.
Implications:
- This case underscores the importance of considering a unique pattern of leptomeningeal metastasis presenting as brainstem lesions, particularly in patients with EGFR-mutated lung adenocarcinoma.
- Repeated CSF cytology and consideration of autoimmune encephalitis are recommended for patients with lung adenocarcinoma and cognitive decline, especially when MRI shows characteristic brainstem lesions.
