How would you approach treatment of metastatic signet cell carcinoma of likely gastrointestinal origin with no primary lesion identified?

I would typically like more information before proceeding. With advanced diagnostics, we have seen the incidence of CUPs fall in recent years but that said, the true CUP still exists.

When stated this is "likely GI origin", I assume that there are IHC features consistent with GI origin such as CK7+ b...

Give FOLFOX.