Which term describes the spread of cancer from the original site?

Metastasis is the term that refers to the process by which cancer spreads from the primary site where it originated to other parts of the body. This occurs when cancer cells break away from the original tumor, travel through the bloodstream or lymphatic system, and form new tumors in different tissues or organs. Understanding this process is crucial because metastasis significantly affects prognosis and treatment options for patients with cancer. Recognizing the distinction between localized and metastatic disease is fundamental in oncology, as it influences staging and therapeutic strategies. This is why "metastasis" is the correct choice for describing the spread of cancer.

The other terms relate to different aspects of cancer: adenocarcinoma is a type of cancer that originates in glandular tissues, oncology is the branch of medicine that studies and treats cancer, and carcinoma in situ refers to a localized cancer that has not yet invaded nearby tissues.