Exceptional symmetric anterior brainstem involvement in leptomeningeal carcinomatosis

Case report: An autopsy report of patient with metastatic brain tumor and carcinomatous meningitis mimicking paraneoplastic neurological syndrome

Differential diagnosis of metastatic brain tumor, carcinomatous meningitis, and paraneoplastic neurological syndrome (PNS) can be challenging in atypical cases. When examining patient with increased T2 fluid-attenuated inversion recovery (FLAIR) hyperintensities in the temporal polar white matter, autoimmune encephalitis, including PNS, should be considered. Herein, we report the case of an 85-year-old man with carcinomatous meningitis due to lung large cell carcinoma. He showed disturbance of consciousness, abnormal behavior, incomprehensible speech, and apathy, which suggested brain dysfunction. Magnetic resonance imaging revealed high intensities on the whole cerebellum on a diffusion-weighted image and bilateral T2 FLAIR hyperintensities in the temporal polar white matter. Cerebrospinal fluid analysis and cytology showed elevated total protein levels, pleocytosis, and atypical cells with nuclear enlargement, hyperchromasia, and irregular shape. Autopsy revealed lung large cell carcinoma and its brain metastasis. Tumor cells were disseminated to the central nervous system along the subarachnoid space. Furthermore, plenty of carcinoma cells and peritumoral enlarged perivascular space were observed in the temporal poles. To our knowledge, this is the first report of bilateral T2 FLAIR hyperintensities in the temporal polar white matter caused by carcinomatous meningitis with pathological confirmation. In patient with carcinomatous meningitis, abnormal T2 FLAIR hyperintensities may not be derived from ischemia or tumor invasion to parenchyma.

A non-enhancing, T2 fluid-attenuated inversion recovery hyperintense, diffusion-restricting brainstem lesion in an EGFR tyrosine kinase inhibitor-treated non-small-cell lung cancer patient

Leptomeningeal metastasis (LM) is a devastating complication of malignancy. Diagnosis relies on both contrast enhancement on imaging and malignant cells in cerebral spinal fluid cytology. Though early detection and prompt intervention improves survival, the detection of LM is limited by false negatives. A rare brainstem imaging finding uncovered specifically in EGFR mutation-positive lung cancer patients may represent an early sign of LM. This sign demonstrates high signal on T2 fluid-attenuated inversion recovery and diffusion-weighted imaging sequences, but paradoxically lacks correlative contrast enhancement. Here we report a case of a 72-year-old female EGFR-positive lung cancer patient who developed this lesion following treatment with two first-generation EGFR tyrosine kinase inhibitors then showed subsequent response to osimertinib, an irreversible third-generation EGFR tyrosine kinase inhibitor.

Extraordinary linear non-enhancing brainstem leptomeningeal metastasis from lung adenocarcinoma: A case report

In patients with lung adenocarcinoma, angiogenesis-altering drugs can alter the appearance of leptomeningeal metastasis on magnetic resonance imaging (MRI) scans. In the ventral brainstem, this can manifest as a unique, linear, non-enhancing T2-hyperintense signal.

Band-Like Brainstem Lesion in a Patient With a History of Lung Adenocarcinoma

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.

Band-like hyperintensity along the ventral surface of the brain stem on FLAIR and DWI in leptomeningeal carcinomatosis of lung adenocarcinoma

Since leptomeningeal carcinomatosis is rarely observed before diagnosis of the primary cancer, its detection is often delayed. We report the case of a 60-year-old woman who presented with lung adenocarcinoma with leptomeningeal carcinomatosis. Magnetic resonance imaging showed the characteristic abnormal hyperintensity along the ventral surface of the brain stem on fluid-attenuated inversion recovery and diffusion weighted imaging. It had no contrast uptake. Based on these findings, we were able to make an early diagnosis of leptomeningeal carcinomatosis of lung adenocarcinoma. This condition was resolved after treatment with a tyrosine kinase inhibitor.

T2-hyperintense, non-gadolinium-enhancing, diffusion-restricted symmetrical curvilinear lesion of the anterior pons: a rare radiological pattern of leptomeningeal metastatic disease secondary to likely lung adenocarcinoma

Leptomeningeal carcinomatosis is a devastating sequelae of metastatic cancer. It has protean manifestations on imaging. An elderly woman presented to our tertiary centre with symptoms suggestive of a cerebrovascular accident. Investigations revealed no evidence of this. There was clinical, contextual and radiological evidence of an underlying neoplasm.Magnetic resonance imaging (MRI) demonstrated evidence of a rare morphology (anterolateral pontine leptomeningeal enhancement) in the presence of a probable concomitant lung adenocarcinoma. Other reports have previously described this same neuroradiology, seemingly always in association with lung adenocarcinoma.The purpose of this report is to highlight an unusual case and discuss its peculiarity and pathophysiology. Our patient is the latest documented of a small cohort with this constellation of clinical and neuroradiological features.This study demonstrates the importance of differential diagnosis in stroke medicine, specifically the need to consider neoplastic phenomena in patients admitted following putative cerebrovascular events.

FLAIR hyperintensity along the brainstem surface in leptomeningeal metastases: a case series and literature review

Background

The incidence of leptomeningeal metastasis (LM) is underestimated because of its non-specific signs and the low sensitivity of clinical diagnostic modalities. Cerebrospinal magnetic resonance (MR) imaging with and without contrast enhancement (CE) is a gold standard for the neuroradiological assessment of patients with suspected LM. Previous studies suggested that some LM cases show changes of the brainstem surface on non-contrast MR images without or before the appearance of abnormalities on CE images. We assessed the features of this non-contrast MR finding in a cohort of LM patients in this retrospective single-institution study.

Methods

We reviewed head MR images and clinical data of 142 consecutive patients in whom the final diagnosis was LM.

Results

We found that 11 of these 142 patients (7.7%) with LM had band-like hyperintensity on the brainstem surface on non-enhanced FLAIR images, which looked like bloomy rind on cheese. Three of seven patients who were examined using diffusion-weighted imaging showed restricted diffusion in the corresponding lesion site. The above-mentioned 11 patients included 10 women and 1 man, with a median age of 61 years. All 11 patients had primary lung adenocarcinoma. Seven patients had symptomatic hydrocephalus. Ten patients had EGFR-mutated and one had ALK-rearrangement adenocarcinomas. Before the diagnosis of LM, 10 patients had undergone systemic therapy with EGFR-TKI or pemetrexed, and 1 patient with ALK inhibitor and bevacizumab.

Conclusions

We present a series of patients with bloomy rind sign that is non-enhancing LM reliably detected by FLAIR hyperintensity on the brainstem surface. This finding is rare, but may reflect the spread of cancer cells in both the leptomeningeal membrane and the surface of the brain parenchyma specifically in patients with lung adenocarcinomas. Further study is needed to determine the clinical significance of this sign, and the pathophysiological factors associated with it may be clarified by analyzing serial MR images in a larger cohort of patients treated for LM.

Novel Anterior Brainstem Magnetic Resonance Imaging Findings in Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

Leptomeningeal carcinomatosis (LC) is found in around 4% of patients with non-small cell lung cancer (NSCLC). The most common radiological finding of LC is diffuse leptomeningeal enhancement on contrast-enhanced brain magnetic resonance imaging (MRI). Herein, we report a novel brain MRI finding-non-enhanced, band-like, symmetric restricted diffusion along the anterior surface of the brainstem-of LC in four patients with NSCLC. We also identified three additional cases with similar MRI findings in a literature review. We hypothesized that the restricted diffusion along the anterior brainstem was caused by malignant cells concentrating in the cistern around the brainstem and infiltrating into the circumferential perforating arteries along the anterior brainstem surface, which then resulted in microinfarctions.

Symmetrical Curvilinear Cytotoxic Edema Along the Surface of the Brain Stem: A Probable New Magnetic Resonance Imaging Finding of Leptomeningeal Carcinomatosis

Lung cancer is one of the most common neoplasms to appear leptomeningeal metastasis (LM). Contrast-enhanced magnetic resonance imaging (MRI) is better diagnostic choice for LM and usually shows focal nodular or diffuse linear enhancement on the leptomeninges along the sulci and tentorium in the brain. We experienced atypical 2 cases of lung cancer in patients who showed unusual brain MRI finding of symmetrical curvilinear or band-like, nonenhancing cytotoxic edema along the surface of the brain stem. This finding is unique and different from the general findings of leptomeningeal metastasis. This unique imaging finding of symmetric curvilinear nonenhancing cytotoxic edema along the brainstem is extremely rare and represents a new presentation of leptomeningeal carcinomatosis.