{"id":28168,"date":"2026-01-24T20:32:10","date_gmt":"2026-01-25T01:32:10","guid":{"rendered":"https:\/\/citystuff.com\/new-york\/2026\/01\/24\/common-condition-may-hide-early-cancer-warning\/"},"modified":"2026-01-24T20:32:11","modified_gmt":"2026-01-25T01:32:11","slug":"common-condition-may-hide-early-cancer-warning","status":"publish","type":"post","link":"https:\/\/citystuff.com\/new-york\/2026\/01\/24\/common-condition-may-hide-early-cancer-warning\/","title":{"rendered":"Common Condition May Hide Early Cancer Warning"},"content":{"rendered":"

Introduction to a Hidden Health Risk<\/h1>\n

Out of sight, out of mind. A new study suggests a common eye condition could be quietly masking one of the only early warning signs of bladder cancer \u2014 the 10th leading cause of cancer deaths in the US.<\/p>\n

The Condition: Color Blindness<\/h2>\n

Researchers found people with the visual impairment were more likely to be diagnosed at later stages, when the disease is harder to treat and survival odds nosedive. Around the world, men are much more likely than women to have the eye condition. <\/p>\n

Color blindness \u2014 also known as color vision deficiency \u2014 affects about 1 in 12 men and 1 in 200 women worldwide. It can be caused by several factors, but it\u2019s most often the result of inherited genetic mutations that affect the retina\u2019s light-sensitive cones.<\/p>\n

Impact on Health<\/h3>\n

The most common form of color blindness makes it difficult to distinguish between red and green \u2014 which past research shows can make it harder to detect blood in the urine. That\u2019s a major problem because blood in the urine is often one of the only early warning signs of bladder cancer, which is typically painless at first.
\nBlood in the urine is an early warning sign of bladder cancer that may go unnoticed in people with certain forms of color blindness. GladkovPhoto \u2013 stock.adobe.com<\/span><\/p>\n

Study Findings<\/h2>\n

Curious whether this could affect patient outcomes, researchers compared the health records of 135 people with both bladder cancer and color blindness with 135 people who had bladder cancer alone. They found that patients with color vision deficiency were more likely to be diagnosed at a more advanced and invasive stage than those with normal vision.<\/p>\n

Comparison and Risks<\/h3>\n

That\u2019s a potential double whammy for men, who are more affected by color blindness and are also four times as likely to be diagnosed with bladder cancer than women. Overall, participants with color blindness had a 52% higher risk of dying within 20 years of their bladder cancer diagnosis compared with the normal-vision group.
\nOnly 11 states require color vision screening for school-aged children, so many cases in the US may never be diagnosed. JU.STOCKER \u2013 stock.adobe.com<\/span><\/p>\n

Broader Implications<\/h2>\n

Past research has also shown that color blindness can make it harder for people to detect blood in stool \u2014 a potential symptom of colorectal cancer, which is rising fast among young Americans. Intrigued, researchers compared colorectal cancer outcomes among patients with and without color blindness, expecting similar results to the bladder cancer group. But notably, they found no statistically significant difference in survival between the two groups.<\/p>\n

Expert Insights<\/h3>\n

They theorized that may be because colorectal cancer often comes with other symptoms \u2014 like abdominal pain and changes in stool habits \u2014 and because screening is widely recommended for Americans ages 45 to 75, making blood detection less critical. By contrast, there is no comparable recommendation for asymptomatic bladder cancer screening. \u201cThere\u2019s much more focus on catching colorectal cancer at an early age and much more public awareness,\u201d Dr. Ehsan Rahimy noted.<\/p>\n

Conclusion<\/h2>\n

The researchers noted several limitations, including that color blindness is often undetected. As a result, some participants may have been incorrectly classified as having normal vision, which could affect the findings. Still, experts say the findings are significant enough to warrant further investigation and may prompt clinicians to be more vigilant with people who have color vision deficiency. Already, Dr. Rahimy has heard from urologists and gastroenterologists who said they had never considered color blindness as a factor in cancer diagnosis. Some said they may begin to ask about it on screening questionnaires. The stakes are high: in 2026 alone, the American Cancer Society estimates that 84,530 new cases of bladder cancer will be diagnosed in the US \u2014 and 17,870 people will die from the disease.<\/p>\n

FAQs<\/h2>\n