"Invasive" - deeper. Skin squamous cell carcinoma (scc) often goes through stages of evolution on its way to becoming "invasive" and eventually metastasizing. It may begin as an area of sun damage or pre-cancer (actinic keratosis) and worsen to become a superficial scc that does not yet invade deeper (scc in situ). Eventually, the scc will start to go deeper and become "invasive", then metastasize if left unchecked.
Invasive. Invasive squamous cell cancer is a cancer that develops within squamous cells. These areas include the skin and lining of the mouth, anus, vagina, etc. Invasive means that the cancer is deeper within this skin or lining and not just at the surface.