> -----Original Message-----
> We have an interesting lesion near the serosal surface in a 
> section of small bowel composed of "signet-ring" -like cells 
> that show immunoreactivity (both nuclear and cytoplasmic) for 
> calretinin.  These same cells are cytokeratin-7 negative; 
> therefore, they are not mesothelial cells.  Any ideas on 
> their lineage?
> 
> R. Cartun 

Are those cells "benign" cells? Most cells of the ovary are calretinin
positive, so I would try also some inhibins (Serotec sells good ones which
stain bright without background) The only other calretinin positive tumor
I'm aware of is myxoma which probable isn't.

Alexander Nader