What does "metastasis" refer to in the field of oncology?

In oncology, "metastasis" specifically refers to the process by which cancer cells spread from the primary tumor, where they initially formed, to other parts of the body. This can occur through various means, such as the bloodstream or lymphatic system. Once cancer cells migrate and establish new tumors in distant organs or tissues, this can complicate treatment and significantly impact patient prognosis. Metastasis is a key concept in understanding the aggressive nature of certain cancers and the importance of early detection and treatment to prevent the spread of the disease. Understanding metastasis is crucial for developing effective cancer therapies and improving outcomes for patients.