Is there a reliable way to distinguish a metastasis from a secondary primary tumor if the histology is the same?
For example, a patient with SCC of the H&N and has a lung mass that is SCC, would these be two separate primaries or metastasis? What is the best way to distinguish a secondary primary from a metastasis?
Answer from: Radiation Oncologist at Academic Institution
This issue may arise when a single lung lesion is found in a previously treated HNC, where distinguishing between a small secondary lung sqcca vs metastatic HNC have significant implications. A comparison of typical molecular characteristics in the primary and the secondary is a possible way. For ex...