Which systemic tumors commonly metastasize to the brain and why do they cause headache?
Lung cancer, breast cancer, colorectal cancer, and melanoma are some of the most common cancers that metastasize to the brain for reasons that are not completely understood. There are studies showing that the brain presents a microenvironment niche that favors the growth of these tumors. Cancer cells can seed multiple areas in the brain including structures with nociceptive receptors such as meninges, blood vessels, and cranial nerves, which cause headache. These cells can also inflame these structures, leading to headache.