Final answer:
Metastasis is the process where cancer cells spread from a primary tumor to distant sites in the body through the bloodstream and form new cancers known as metastases.
Step-by-step explanation:
The process by which malignant cells reach the bloodstream or lymphatic system, spreading throughout the organism, and forming secondary colonies at other sites is known as metastasis. These secondary colonies are called new cancers or metastases. Malignant tumors, also known as malignant neoplasms, can grow and spread beyond the original tumor's boundaries. As cancer cells metastasize, they can become the origin of new tumor formation in different tissues within the body. Notably, almost all cancers can metastasize, particularly in the latter stages of the disease, and metastases are often associated with the worst prognoses and most cancer deaths.