Has anyone talked with a doctor about the RGCC cancer testing?

I suppose it's natural to be curious about a test/tests that claims to be able to pick up evidence of circulating tumor cells, right? Don't we all want that -- to know whether there's cancer somewhere else in our bodies? But oh the cost. Sooo expensive. And I don't even know if it's reliable, or if I'm just wishfully thinking.

Does anyone know anything about CTC (circulating tumor cell) or liquid biopsy tests and whether there's any real value there?

Hugs, everybody.