Black spots on toenails. Cancer.

Toenail cover black spots This is not a symptom of cancer, toenail with black spots may be a patient's long-term lack of trace elements, may also be due to external factors caused by toenail injury, caused by nail bleeding, blood coagulation. May also be a precursor of brain blood circulation disorders, but also may be a lack of vitamins in the body, resulting in capillary rupture, patients should do an EEG to rule out.