How do you approach a patient with an anaplastic plasmacytoma without systemic evidence of disease in the bone marrow?

I'm not sure what an anaplastic plasmacytoma is. Is it a plasmacytoma that is made up of amorphous cells that express CD138, are clonal, and don't express EBER, ALK, or HHV8? This seems to follow along the lines of what is a plasmablastic neoplasm.

If there are no clonal plasma cells in the marrow, ...

Agreed with @Dr. First Last on all fronts above. I'll specifically touch on the follow-up question (multiple biopsy-proven anaplastic plasmacytomas but BM neg).

My vote, in that case, would be to repeat the bone marrow, since I'd argue that the chances of this scenario truly unfolding are infinitesi...