Cancer may increase the risk of blood clots, which can lead to stroke in some patients, according to a major review of scientific studies. Stroke is a common neurological issue among cancer patients, especially after cancer spreads to the brain. Researchers in Spain analyzed up to 82 studies conducted between 2000 and 2025 to better understand the connection between cancer and stroke. They examined various aspects, including how often this happens, the symptoms, and the biological processes involved, focusing on a condition known as cancer-associated coagulopathy (CAC). Their findings, published in the Journal of Neurology, showed that strokes linked to cancer often occur within six months of diagnosis, and many patients had already developed metastasis—cancer that has spread to other parts of the body—by the time they had a stroke. The study found that certain cancers, particularly those affecting the lining of the lungs and the pancreas, are most commonly linked to stroke. In these cases, the time between cancer diagnosis and stroke is often very short. The risk of blood clots forming in major arteries peaks in the first year after a cancer diagnosis. In about 72 percent of cases, stroke was the most common complication. While this risk decreases over time, it remains higher than in the general population for up to a decade after diagnosis. Scientists believe that several complex biological processes may link cancer to stroke. One possible mechanism involves a sticky molecule called mucin, which some cancer cells produce. This substance may cause platelets—small blood cells that help with clotting—to clump together. Other factors, such as particles released from cells and immune cells known as neutrophils, may also contribute to clot formation. Doctors can detect signs of clotting by measuring levels of a protein fragment called D-dimer, which is released when a clot breaks down. High levels of D-dimer are often linked to cancer recurrence and higher mortality risk. The researchers also noted that certain MRI patterns—showing damage in three different areas of the brain—can be a strong indicator of stroke caused by cancer. They emphasized that as cancer rates are expected to rise globally and more people survive cancer, the number of strokes related to cancer is likely to increase. This highlights the need for better recognition and management of CAC-related stroke in clinical settings.