How can lung cancer spread to bone?

Lung cancer spreads to distant sites, including the bone, through a complex biological process known as metastasis.

To disseminate, malignant cells must detach from the primary tumor, penetrate the basement membrane of nearby tissues using specialized enzymes, and enter the circulatory system or lymphatic vessels. Once in the bloodstream, these cells travel throughout the body, eventually lodging in the capillaries of distant organs.12

While blood flow patterns influence where cells settle, the spread to specific tissues is often driven by a "homing" mechanism. This phenomenon occurs when receptor proteins on the surface of cancer cells recognize and bind to specific molecules within the "soil" of a target tissue, such as the bone. This interaction allows the cancer cells to exit the circulation and establish a secondary tumor. Although lung cancer frequently seeds the adrenal glands, it can also metastasize to the bone through these same complex molecular affinities and genetic alterations.12