CEACAM5 and breast cancer: Four vaccines—PANVAC; a related CEA vaccine with the same stimulating proteins, a yeast-based vaccine targeting brachyury; a transcription factor associated with tumor epithelial-mesenchymal transition, and viral vaccines containing the NY-ESO-1 antigen, have all produced SD in varying proportions of carcinomas, although these studies contained small numbers of breast cancer patients and did not have control groups52–55.