NCIt definition : A malignant tumor that arises at a site separate from another, primary malignant tumor
in the same anatomic system. It is not clear if metachronous malignant neoplasms represent
new primary tumors or metastatic disease. Examples include metachronous osteosarcoma
of the bones that develops in patients with known primary bone osteosarcoma, and metachronous
Wilms' tumor that affects the opposite kidney in patients with a history of Wilms'
tumor.;
Semantic type(s)