3. Nail Clubbing
Fingernail or toenail clubbing is a result of a weakened nail bed. The nails grow in a more curved manner, further around the tips of the fingers rather than straight. The nail bed is weakened by certain substances that are secreted by cancer cells.
Clubbing is used as a way to help determine the progression of a patient’s lung cancer. In early-stage lung cancer, for example, the nail bed is soft, skin is smooth, and the nails appear more curved than normal when viewed from the top. The fingertips themselves may also be enlarged.
In addition to fingernail or toenail clubbing, joints in the fingers and wrists can also be enlarged in patients with advanced lung cancer, due to additional bone growth triggered by cancer.