# Leptomeningeal Metastasis: A Rare Complication of Non-small Cell Lung Cancer

## TL;DR

This paper discusses a rare case of leptomeningeal metastasis from non-small cell lung cancer misdiagnosed as an inflammatory condition.

## Contribution

The novelty lies in highlighting the diagnostic challenges of LMM when it mimics inflammatory diseases like lupus.

## Key findings

- LMM can present with symptoms similar to inflammatory neuritis, leading to misdiagnosis.
- Including LMM in the differential diagnosis is crucial for patients with unexplained neurological symptoms.
- The case emphasizes the need for thorough evaluation in patients with atypical presentations.

## Abstract

Leptomeningeal metastasis (LMM) is a rare complication of non-small cell lung cancer (NSCLC) that can present with a range of neurological symptoms depending on the site(s) of metastatic involvement. We present a case of a 54-year-old woman who was initially diagnosed with suspected inflammatory neuritis secondary to a known systemic lupus erythematosus (SLE) diagnosis after presenting with multiple months of progressive neuro-ophthalmologic symptoms; however, she was eventually diagnosed with LMM secondary to a previously undiagnosed NSCLC. This case both underscores the challenges of diagnosing LMM due to its nonspecific presentation, as well as highlights the importance of including LMM in the differential diagnosis for patients presenting with vague neurological symptoms in the context of another inflammatory disease process.