The rarity of sternal tumors makes a good comparative study a difficult task. Controversies exist on questions of method of surgical diagnosis, the extent of the surgical procedure, and the different ways and means of reconstruction. We describe a case that was believed to be a clear case of chondrosarcoma but was actually a plasmacytoma. From the evidence of this case and a review of the literature we conclude that almost any plasmacytoma should be considered generalized multiple myeloma. Biopsy should be performed in all cases of sternal tumor before any surgical action is taken.