Small Cell Lung Carcinoma Presenting as Collapsin Response-Mediating Protein (CRMP) -5 Paraneoplastic Optic Neuropathy

Collapsin response mediator protein 5-associated optic neuropathy: clinical characteristics, radiologic clues, and outcomes

Objective

Collapsin response mediator protein 5-associated optic neuropathy (CRMP5-ON) is a rare entity of autoimmune optic neuropathy. This study aimed to review the neuro-ophthalmic findings and outcomes in a series of patients with CRMP5-ON to further characterize its clinical phenotype, radiologic clues, and outcomes.

Methods

This was a retrospective case series and a single-center medical chart review of all patients with CRPM5-seropositive ON at the Department of Neurology, Beijing Tongren Hospital, from December 1, 2020, to March 31, 2023. The main outcome measures were neuro-ophthalmic manifestations, radiologic characteristics, and clinical outcomes of CRMP5-ON; coexisting neural autoantibody, paraneoplastic associations, and the impact of immunosuppressant therapy.

Results

Five patients were identified. Four (80%) were female, and the average age at onset was 59.4 years (range 53-69 years), with an average follow-up of 15.3 months (range 1.4-28.7 months). The average best-corrected visual acuity (BCVA) at nadir was 20/120 (range 20/20 to count fingers). Seven of ten affected eyes (70%) showed diffuse defects of the central field. Painless bilateral involvement and optic disk edema occurred in 100% of patients, combined with vitritis, uveitis, or retinitis in four (80%). Four patients (80%) had MRI abnormalities along the optic nerve (one patient with optic nerve enhancement and three patients had optic nerve sheath enhancement or peribulbar fat enhancement). Three patients (60%) had optic neuropathy with other neurologic symptoms. Four patients (80%) had confirmed cancer (two were small-cell lung carcinoma, one was papillary thyroid carcinoma and another was thymoma and invasive pulmonary adenocarcinoma). All cancers were identified after the presentation of the optic neuropathy. The intervention included IVIG, IVMP, surgery and chemotherapy. The average BCVA at the last follow-up was 20/50 (range 20/20 to count fingers). Three patients had surgery during the initial hospitalization, and were stable during the follow-up. Among two patients who received IVMP, both had improvement after treatment, although one patient had worsening non-ocular neurologic symptoms during the steroid taper.

Conclusion

CRMP5-ON presented with optic disc edema, often bilateral involved and combined with vitreitis, retinitis, or uveitis. CRMP5-ON can present with MRI optic nerve or perineural optic nerve enhancement, especially in the optic nerve sheath. CRMP5-ON is closely related to paraneoplastic neurologic syndrome. Cancer screening and intervention are crucial to prognosis.

Paraneoplastic ocular syndrome: a pandora's box of underlying malignancies

Paraneoplastic syndromes affecting the visual system are a group of conditions that arise in the systemic malignancy framework. In this review, we have provided a detailed and comprehensive overview of the published literature on the various ophthalmic paraneoplastic manifestations. A systematic review of many databases has been performed to identify ample literature on the paraneoplastic syndromes related to ophthalmology. We have discussed here the clinical features, pathogenesis, and treatment strategies of various ophthalmic paraneoplastic syndromes. It can be challenging to distinguish these disorders from their non-paraneoplastic counterparts and to determine the appropriate systemic assessment for the tumour responsible, to have a proper approach towards the management of the syndrome. METHOD: We searched PubMed, Science Direct and Journal of Ophthalmology for studies published in English between 1995 and April 2020, incorporating the general search term "paraneoplastic ocular syndrome" with connecting terms relevant to subheadings-e.g. Key search terms were cancer-associated retinopathy, (CAR), melanoma-associated retinopathy, (MAR), paraneoplastic retinopathy, autoimmune retinopathy, autoimmune-related retinopathy, and optic neuropathy, (ARRON), acute zonal occult outer retinopathy, (AZOOR), paraneoplastic vitelliform maculopathy, paraneoplastic vitelliform retinopathy, bilateral diffuse uveal melanocytic proliferation, (BDUMP), paraneoplastic optic neuropathy, (PON), polyneuropathy, organomegaly, endocrinopathy, monoclona gammopathy, and skin changes syndrome (POEMS) and various other terms. References from identified studies have been reviewed and included if deemed appropriate, valid, and scientifically important. If referenced in a selected English paper, we contemplated papers in other languages too. We preferentially selected papers that have been published in the last 10 years, but we have included relevant older references.

Vision Improvement after Osimertinib Treatment in Paraneoplastic Optic Neuropathy Associated with Lung Adenocarcinoma

Treatments for paraneoplastic optic neuropathy (PON), a tumor-related autoimmune disease, include immunosuppression, plasma exchange, and immunoglobulin therapies, as well as treatment of the underlying disease. Herein, we describe the clinical course of an older adult patient with PON whose loss of vision improved after switching between epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) treatments for cancer. A 76-year-old woman, who had been treated with gefitinib for lung adenocarcinoma for two years, presented with acute bilateral visual disturbances. Her decimal best-corrected visual acuity (BCVA) was 0.3 in the right eye (RE) and 0.7 in the left eye (LE). Slit-lamp examination and funduscopy showed no abnormal findings. Two weeks later, her BCVA decreased to 0.2 in the RE and 0.01 in the LE. Goldman's perimetry showed a defect in the lower nasal RE and extensive visual-field loss in the LE. Single-flash electroretinograms showed normal amplitudes. Magnetic resonance imaging revealed left optic neuritis and showed neither metastatic cancer nor multiple sclerosis. Pattern-reversal visual evoked potentials showed decreased P100 amplitudes in both eyes (BE). Based on a diagnosis of PON from clinical findings, methylprednisolone pulse treatment was administered. However, her BCVA became no light perception in BE two months after the first visit. Because the tumor tissue was found to be positive for the EGFR T790M resistance mutation by bronchoscopy, the EGFR-TKI treatment was changed to osimertinib, decreasing the size of the lung cancer lesions. Her BCVA improved to hand motion in BE. Her final BCVA was 0.01 in the RE, counting fingers 10 cm in the LE. She died at the age of 79 years. To our knowledge, no reports have shown improvement in BCVA in patients with PON after changing EGFR-TKI treatments. This report indicates that some patients may develop severe visual dysfunction without early treatment for the primary tumor.

Small cell carcinoma presenting as ocular paraneoplastic syndrome due to CRMP-5

We report the case of a lady who presented with 3 weeks of visual floaters and optic disc swelling. Subsequent investigations revealed deep white matter changes on brain imaging, and enlarged mediastinal nodes. The presence of anti-CRMP-5 antibodies finally led to the diagnosis of a paraneoplastic syndrome, and mediastinal lymph node biopsy confirmed the diagnosis of small-cell lung cancer. The learning points from this case include that optic neuritis can be the only presenting feature of a paraneoplastic neurological syndrome, and the usefulness of anti-neuronal antibody measurement as a diagnostic marker of an underlying paraneoplastic disease process. The great challenge is to recognise these tumour-associated autoimmune system presentations early, as they often appear long before the primary cancer is evident. Prompt treatment leads to an earlier reduction in circulating auto-antibody possibly due to reduction in tumour size, and thus less likelihood of permanent neuronal damage.

Paraneoplastic Syndromes in Neuro-ophthalmology

PURPOSE OF REVIEW

This article discusses the varied types of paraneoplastic syndromes that commonly have neuro-ophthalmologic manifestations. Diagnostic considerations and therapeutic options for individual diseases are also discussed.

RECENT FINDINGS

Paraneoplastic syndromes can affect the afferent and efferent visual systems. Paraneoplastic syndromes may result in reduced visual acuity from retinal degeneration, alterations in melanocyte proliferation and uveal thickening, or acquired nystagmus. Ocular motor abnormalities related to paraneoplastic syndromes may present with symptoms from opsoclonus or from neuromuscular junction disease. Diagnosis remains challenging, but serologic identification of some specific antibodies may be helpful or confirmatory. Treatment, in addition to directed therapies against the underlying cancer, often requires systemic corticosteroids, plasma exchange, or immunosuppression, but some specific syndromes improve with use of targeted pharmacologic therapy.

SUMMARY

Diagnosis and therapy of paraneoplastic syndromes presenting with neuro-ophthalmic symptoms remain a challenge, but strategies are evolving and new approaches are on the horizon.

DRP5 is involved in cancer cell growth and predicts poor prognosis in human osteosarcoma

Osteosarcoma is an extremely aggressive primary malignant bone tumor of childhood. Collapsin response mediator proteins (CRMPs), which are highly expressed in the developing nervous system, were recently shown to be associated with cancer development. However, the relationship between DRP5 (CRMP5) and osteosarcoma has not been evaluated. In this study, we investigated the role of DRP5 in the regulation of osteosarcoma growth. DRP5 mRNA and protein levels were significantly upregulated in human osteosarcoma cell lines and associated with increased migration and invasion. Genetic knockdown of DRP5 markedly suppressed the expression of matrix metalloproteinase (MMP)‐2 and MMP‐9. DRP5 silencing significantly inhibited osteosarcoma cell growth in vitro and in a xenograft mouse model in vivo. Microarray immunohistochemical analysis of osteosarcoma specimens and Kaplan–Meier analysis showed that patients with high DRP5 protein expression had shorter overall survival than those with low DRP5 levels. Taken together, these results suggest that DRP5 plays a critical role in the regulation of osteosarcoma and could be a potential therapeutic target and prognostic factor in osteosarcoma.

Autoimmune paraneoplastic syndromes associated to lung cancer: A systematic review of the literature: Part 3: Neurological paraneoplastic syndromes, involving the central nervous system

The development of new immune treatment in oncology and particularly for lung cancer may induce new complications, particularly activation or reactivation of auto-immune diseases. In this context, a systematic review on the auto-immune paraneoplastic syndromes that can complicate lung cancer appears useful. This article is the third of a series of five and deals mainly with neurological paraneoplastic syndromes involving the central nervous system.

Anti-Collapsing Response-Mediating Protein-5 Antibody-Positive Paraneoplastic Perioptic Neuritis without Typical Neurological Symptoms

A 68-year-old male presented with blurred vision in both eyes. Ophthalmoscopy revealed bilateral prominent disc swelling and vitritis. No systematic neurological symptoms were observed. Magnetic resonance imaging revealed bilateral meningeal enhancement of the optic nerve. Small cell carcinoma was found, and antibodies against collapsing response-mediating protein-5 (CRMP-5) were detected in the serum. Ophthalmological manifestations disappeared during a decrease in tumour size with treatment for the malignancy. This case report describes this rare case of anti-CRMP-5 antibody-positive paraneoplastic perioptic neuritis without neurological symptoms, showing that prompt diagnosis and timely treatment of the underlying tumour are crucial to prevent increased levels of autoantibodies and irreversible damage to the nervous system.

Paraneoplastic Optic Neuropathy Associated With Purkinje Cell Antibody-2 in a Patient With Small Cell Lung Cancer

Paraneoplastic optic neuropathy (PON) is a rare cause of vision loss usually associated with small cell lung cancer. Patients with this condition usually test positive for anti-collapsin response mediating protein-5 (CRMP-5). We describe a case of a 57-year-old woman with bilateral vision loss with the characteristic features of CRMP-5 PON including bilateral optic disc edema and vitreous cells. However, she was negative for anti-CRMP-5 including a negative Western blot on two occasions, but positive for Purkinje Cell Antibody (PCA)-2. Although paraneoplastic antibodies are more predictive of an underlying cancer than a specific syndrome, previously PON has not been associated with PCA-2. Based on this observation, we recommend that the workup should include PCA-2 antibodies in patients who present with bilateral optic neuropathy and vitreous cells.

Paraneoplastic Syndromes in Neuro-Ophthalmology

BACKGROUND

Paraneoplastic syndromes that affect the visual pathways and present with neuro-ophthalmologic signs or symptoms may involve the afferent or efferent systems. Afferent syndromes may involve the optic nerve or retina and, in some cases, these may be associated with systemic neurologic disease. Efferent symptoms typically affect eye movements and may involve the neuromuscular junction or involuntary eye movements.

EVIDENCE ACQUISITION

Literature review and personal clinical and research experience.

RESULTS

Diagnosis of paraneoplastic syndromes relies on clinical and laboratory evaluations. In the appropriate clinical setting, the presence of specific antibodies may help confirm the diagnosis.

CONCLUSIONS

In some cases, the visual pathway disturbance precedes a diagnosis of malignancy. Astute observation and selective evaluation and management are critical to establish the correct diagnosis and institute therapeutic approaches that can be sight or life saving.

Clinical and Histological Features of Small Cell Lung Cancer Paraneoplastic Inflammatory Uveitis

PURPOSE

Paraneoplastic ocular inflammation can be associated with the autoantibody against collapsin response-mediator protein-5 (anti-CRMP-5). We describe the clinical and histological features of 2 rare cases of small cell lung carcinoma (SCLC) presenting with intraocular inflammation: the first was anti-CRMP-5 positive and the second preceded the auto-antibody's discovery but with remarkably similar features. The previously unreported retinal histology is described.

METHODS

Case notes review.

RESULTS

Both cases presented with bilateral visual loss, constricted visual fields, vitritis, and pale, swollen optic discs. Fundal fluorescein angiographies showed optic disc leakage. Retinal histology of both cases revealed predominantly inner retinal inflammation. Following their diagnosis with SCLC, serology for case 1 was positive for anti-CRMP-5 but case 2 pre-dated its discovery.

CONCLUSIONS

CRMP-5 inflammatory eye disease presents with a distinct pattern of clinical and histological features, which may be the first sign of their underlying cancer. Retinal histology revealed predominantly inner retinal inflammation.

Paraneoplastic syndromes in neuro-ophthalmology

PURPOSE OF REVIEW

The aim of this review is to discuss and highlight the recent advances in our understanding of paraneoplastic syndromes in neuro-ophthalmology and their significance.

RECENT FINDINGS

The pathophysiologic mechanism in neuro-ophthalmic paraneoplastic syndromes involves an immune response triggered by aberrant expression of onconeuronal antigens that cross-react with antigens in the visual system. Recently, 18-fluoro-deoxy-glucose/positron emission tomography with computed tomography scanning has emerged as a useful modality in diagnosing occult tumors responsible for paraneoplastic syndromes. Paraneoplastic optic neuropathy has been recently associated with the anti-CV2/CRMP-5 antibody. The use of serologic analysis of recombinantly expressed clones (SEREX) has led to the identification of new antigens associated with melanoma-associated retinopathy, such as visual arrestin, rhodopsin, titin, and mitofilin. Calcium-channel blockers and alemtuzumab have been found to improve visual function in cancer-associated retinopathy. Rituximab has been found to be effective in childhood opsoclonus-myoclonus syndrome.

SUMMARY

A high index of suspicion is needed to diagnose neuro-ophthalmic paraneoplastic syndromes. There have been recent advances in our understanding of the pathophysiology and treatment of these disorders. This will facilitate early treatment of causative occult tumors and improves the prognosis.