Woman's sudden blindness in 1 eye revealed hidden lung cancer

In an extremely rare case, a woman's sudden blindness in one eye turned out to be the first symptom of undiagnosed lung cancer that had spread throughout her body. 

The woman first sought medical attention after losing vision in her right eye and experiencing occasional flashes of light in her left eye for around 20 days. She was 32 years old at the time and otherwise healthy, with no other symptoms and no history of smoking. 

During an initial eye exam at the hospital, doctors determined her eyes looked Healthy. They were not painful or red and the eye's key structures appeared intact — the lens was clear, and the pupil and iris, or colored part of the eye, didn't show noticeable abnormalities. 

However, upon closer inspection, doctors saw that there was a large, whitish-yellowish mass growing in the back of her right eye. Fluid had also accumulated under her retina, the light-sensitive part of the eye, causing it to detach. There was a similar, smaller lesion in her left eye, but its retina was still intact.  

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To determine what caused these masses to appear, doctors checked the woman's blood. They found that she had no signs of an active viral infection or blood disorder, as her red blood cell and immune cell counts were normal. She was didn't have an human immunodeficiency virus (HIV) infection or an autoimmune disease, both of which can make people more vulnerable to vision loss and changes. 

Finally, a chest X-ray and whole-body scan revealed the culprit — a mass of cancerous tissue growing in the lower part of the woman's right lung. This tumor had spread to multiple other organs, including part of the eyes called the choroid.