Definition: Brain metastases are cancer cells that have spread to the brain from primary tumors in other organs.

Current Status and Incidence: As imaging techniques improve, brain metastases are increasingly detected with the most common sources being lung cancer, breast cancer, melanoma, renal cell carcinoma, and colorectal cancer.

Treatment Methods: Includes surgical removal, stereotactic radiosurgery, whole-brain radiation therapy, and sometimes chemotherapy or targeted therapies based on the type of primary cancer.

Definition: Abdominal metastases occur when cancer cells spread to abdominal organs from primary tumors located elsewhere in the body.

Current Status and Incidence: The incidence varies widely depending on the type of primary cancer. For example, colorectal cancer frequently metastasizes to the liver.

Treatment Methods: Often involve systemic chemotherapy, radiation therapy, and targeted treatments, as well as surgical resection when feasible.