Clin Oncol | Volume 4, Issue 1 | Research Article | Open Access

CRMP-5 Positive Paraneoplastic Optic Neuropathy as Initial Presentation of Small Cell Lung Cancer

Dante M Sorrentino, Jennifer Lee and Gabrielle R Bonhomme*

Department of Neuro-Ophthalmology, University of Pittsburgh Medical Center, USA

*Correspondance to: Gabrielle R Bonhomme 

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Paraneoplastic neurologic syndromes are manifestations of systemic malignancies. It is recognized as an immune mediated response that can rarely present as an optic neuropathy. Advancement in anti-neuronal antibody testing had led to increased identification of this paraneoplastic process. We describe a unique case of a 72-year-old male who presented with bilateral blurry vision and was found to have asymmetric optic disc edema on exam. His visual symptoms and exam findings were rigorously investigated with imaging, serology testing, lumbar puncture, ophthalmic ancillary testing, and biopsy. His chest and abdominal imaging were concerning for lung cancer. The suspicion of a metastatic neuroendocrine lung primary was confirmed by fine-needle aspiration biopsy. His serology and cerebrospinal fluid were positive for an anti-neuronal autoantibody known as Collapsin Response-Mediator Protein-5 (CRMP 5). He was subsequently diagnosed with Paraneoplastic Optic Neuropathy (PON) due to metastatic small cell lung carcinoma. Unlike other cases of PON, our patient’s vision loss prompted work-up for malignancy. Moreover, he did not demonstrate the typical findings associated with PON such as vitreous inflammation, brainstem dysfunction, or cerebellar dysfunction. With chemotherapy and corticosteroids, his vision recovered. This case demonstrates the importance of recognizing vision loss as a sign of PON, a rare manifestation of systemic malignancy.


Sorrentino DM, Lee J, Bonhomme GR. CRMP-5 Positive Paraneoplastic Optic Neuropathy as Initial Presentation of Small Cell Lung Cancer. Clin Oncol. 2019; 4: 1620.

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