BIRC5 and pituitary tumor: A comparison of the variation in survivin expression between pituitary tumors and positive control-thyroid cancers revealed a significantly higher expression of survivin (P < 0.0001), and its variants: ∆Ex3, P < 0.0001 and 2β, P = 0.0008 in the thyroid cancer group (Figs. 1, 2, 3).