Cancer signals from the feet may include black dots on the feet, abnormal shape of the toes, pain in the feet, etc. However, a single symptom cannot be used to diagnose the disease, and it is recommended to seek medical attention when there is any discomfort. If a black spot suddenly appears on the foot, it may be some skin disease, such as a pigmented mole or a plantar wart, but it may also be a skin cancer like melanoma, which may appear as a black spot when it appears on the foot. If the shape of toes is abnormal, besides it may be caused by congenital developmental deformity, or shoe discomfort squeezing the toes, rheumatoid arthritis, etc., it may also be caused by pestle finger due to lung cancer, which is mainly manifested by the abnormal swelling of the end of the toes, thickening and protruding on the surface of the skin. If there is pain in the feet, besides the common ones caused by rheumatic arthropathy, gout, neuralgia, etc., it may also be the pain caused by certain cancers metastasized to the feet. These symptoms may be cancer signals from the feet, but diagnosis cannot be made only by a single symptom, and a comprehensive examination combined with other clinical symptoms is needed to confirm the diagnosis.