Retinoblastoma is a rare cancer of the eye, so it might be mistaken for other conditions. Some of these conditions include retinal detachment, astrocytoma, Coats’ disease, or choroidal melanoma. Retinal detachment is a condition where the inner and outer layers of the retina separate, and may cause blurred vision, flashes, or floaters. Astrocytoma is a tumor that develops from astrocytes, star-shaped cells in the brain, and can lead to vision loss. Coats’ disease is a rare disorder where abnormal blood vessels grow in the retina and can cause vision loss. Lastly, choroidal melanoma is a rare tumor in the eye, and can cause blurred vision, floaters, blind spots, or a change in pupil size. All of these conditions can have similar symptoms to retinoblastoma, so it is important to seek medical attention if you experience any of these symptoms.