MAGE-A3 is expressed in about 35% of newly diagnosed MM and more that 75% of relapsed MM cases [9], which is substantially higher than in most other cancers; by comparison, MAGE-A3 is expressed in about 50% of non-small cell lung cancers, 36% of melanomas, and 20% of breast cancers [1]. This evidence concerns the gene MAGEA3 and cancer.