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Simulate paraneoplastic retinopathy — a group of immune-mediated retinal degenerations triggered by the abnormal expression of retinal antigens by tumour cells in patients with systemic cancer, leading to the generation of circulating autoantibodies that cross-react with retinal neurons and cause progressive photoreceptor or bipolar cell destruction even when the primary tumour remains small, occult, or successfully treated. Three distinct clinical syndromes are recognised: (1) Cancer-Associated Retinopathy (CAR) — the most common and most severe form, typically associated with small cell lung carcinoma (SCLC), breast carcinoma, gynecological malignancies (ovarian, uterine, cervical), and prostatic carcinoma. The key pathogenic autoantibody in CAR targets recoverin (23 kDa retinal calcium sensor protein, encoded by RCVRN) — a photoreceptor protein expressed ectopically by SCLC cells that triggers an aberrant anti-tumour immune response cross-reacting with native retinal recoverin. Anti-recoverin IgG antibodies enter retinal photoreceptors, bind recoverin, and trigger caspase-mediated apoptosis of rods and cones, causing progressive bilateral visual loss with severe ERG amplitude reduction affecting both photopic and scotopic responses. (2) Melanoma-Associated Retinopathy (MAR) — associated with cutaneous (not uveal) melanoma metastases; characterised by acute-onset shimmering photopsias, night blindness, and visual disturbance. The pathogenic autoantibodies in MAR target TRPM1 (transient receptor potential melastatin subtype 1) — an L-type calcium channel expressed on ON-bipolar cell dendrites in the inner nuclear layer. Anti-TRPM1 antibodies block ON-bipolar cell glutamate-gated signalling, producing a characteristic ERG pattern: normal photoreceptor A-wave with absent ON-bipolar B-wave (electronegative ERG — identical to complete CSNB), and preserved but attenuated OFF-pathway responses. Unlike CAR, MAR may not cause structural photoreceptor loss on OCT. (3) Paraneoplastic optic neuropathy with retinal involvement — rare combination of retinal ganglion cell and optic nerve degeneration alongside inner retinal atrophy from anti-CV2/CRMP5 or anti-Hu antibodies, producing a mixed retinopathy-optic neuropathy syndrome with cecocentral scotoma and colour vision loss preceding the retinopathy signs. Model three states with ΔE colour shift, CIE xy chromaticity, and image simulation.

Paraneoplastic retinopathy colour science simulation by Auric Artisan.

Base color
Paraneoplastic subtype & settings
Retinal degeneration severity 50%
Image simulation
Upload JPG/PNG (max 1200 × 1200). See how a scene appears through CAR pan-photoreceptor apoptosis (combined rod and cone signal loss), MAR ON-bipolar block (abnormal ON-pathway processing, preserved photoreceptor input), or paraneoplastic optic neuropathy (inner retinal and optic nerve degeneration producing cecocentral scotoma with colour vision loss).
Research notes
Paraneoplastic retinopathy is a medical emergency: visual loss may be the presenting sign of an occult systemic cancer, often preceding the cancer diagnosis by 3–18 months. Urgent serum anti-retinal antibody panel (anti-recoverin, anti-TRPM1, anti-α-enolase, anti-carbonic anhydrase II, anti-aldolase C, anti-Crx, anti-arrestin) combined with whole-body CT-PET scanning is the essential first investigation. Visual prognosis in CAR is poor without aggressive immunosuppression — once established, photoreceptor apoptosis may be irreversible even with successful cancer treatment. MAR prognosis is more variable given the bipolar cell localization (photoreceptors intact) which preserves some structural retinal reserve. The key clinical teaching point: any patient with unexplained bilateral progressive visual loss and a known or suspected cancer diagnosis must have anti-retinal antibody testing and urgent electroretinography.
Swatches
Normal
HEX: — • RGB: — • xy: —
PR affected
HEX: — • RGB: — • xy: —
ΔE (CIE76)
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ΔE (CIEDE2000)
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Deep preview
Normal
PR (deep)
Chromaticity (CIE xy)
Autoimmune photoreceptor loss chromaticity shift
D65 white point: 0.313, 0.329
Image simulation

Paraneoplastic retinopathy simulations model immune-mediated retinal signal loss using subtype-specific antibody target models in the sRGB colour space. CAR (anti-recoverin): models pan-photoreceptor apoptosis as progressive combined L, M, and S cone loss plus rod pathway loss — producing severe mixed achromatic visual impairment converging toward the D65 white point with increasing severity. MAR (anti-TRPM1): models ON-bipolar cell signal block as a selective attenuation of the ON-pathway signal contribution — preserving initial photoreceptor input but suppressing the processed retinal output signal passed to retinal ganglion cells, modelled as mixed luminance reduction with preserved-but-attenuated colour contrast. Paraneoplastic optic neuropathy: models combined inner retinal and optic nerve degeneration as a retinal ganglion cell loss pattern with preferential loss of colour-opponent and high-spatial-frequency luminance channels. ΔE2000 per Sharma et al. (2005). Not for clinical diagnosis — paraneoplastic retinopathy is a medical emergency requiring full-field ERG, anti-retinal antibody serology, and urgent whole-body CT-PET. Progressive visual loss in a cancer patient must be evaluated immediately by neuro-ophthalmology.

Multi-condition comparison
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Compare CAR pan-photoreceptor apoptosis vs MAR ON-bipolar cell signal disruption vs paraneoplastic optic neuropathy. Observe the distinct chromatic and luminance signatures of antibody-specific retinal circuit disruption.