New York doctor warns that change in fingernails can be linked to lung cancer

He says anyone who notices it, even without other symptoms, should seek medical attention

Rowan Dunne

Published

August 7, 2025

Discoloured or misshapen fingernails and fingertips can be indicators of the world’s deadliest cancer, according to an Iranian doctor in Brooklyn.

Dr. Davood Johari from New York City Health + Hospitals recently used World Lung Cancer Day on Aug. 1 as an opportunity to warn people not to overlook these symptoms. Between 5 to 15 per cent of lung cancer patients experience what is known as “fingernail clubbing” or digital clubbing, and it often appears in the disease’s late stages of progression.

“Fingertips appear wider and rounder than normal, with the nails curving downwards, resembling an upside-down spoon,” he told the New York Post early this month. Johari added that the area under a fingernail may feel softer and fingertips can be red or warmer than usual.

He is urging anyone who experiences any of these symptoms to seek medical attention even if they feel normal otherwise.

Although the condition is known to indicate lung cancer in certain cases, it can be a sign of other lung infections and illnesses. These include cystic fibrosis, liver disease, Crohn’s, other cancers and cardiovascular diseases.

In addition to this particular symptom of the hands, Johari says those with a persistent cough lasting any longer than a couple of weeks should visit a hospital or clinic. Furthermore, people with unexplained vocal changes, drooping eyelids, unusual shoulder pain and vision abnormalities should as well. Coughing up blood is one of the more alarming potential symptoms of the disease.

Early detection through regular screening for those eligible is also a key means of fighting against lung cancer. Unfortunately, the current gold standard for lung cancer screening, low-dose CT scans, are expensive to operate and maintain. This contributes to a limited number of people in their later years being able to receive a scan.

Moreover, they expose the patient to radiation and yield a high rate of false positive results, thereby making the risk of being screened outweigh the benefits for low-risk individuals. A highly concerning study from the University of California this year estimated that 5 per cent of new lung cancer cases in the U.S. resulted from usage of the screening machines in 2023.

Thankfully, new technologies like the highly accurate breath testing system developed by Breath Diagnostics are helping to make the future of lung cancer screening more convenient, accurate, non-invasive and inexpensive.