IGF1 and pituitary gland adenoma: MRI intensity patterns have been studied to better characterize different subtypes of pituitary adenomas: a study from Gruppetta reports that hypointensity on T2-weighted sequences is more frequent in GH-secreting pituitary adenomas, compared to other adenoma subtypes; in addition, among GH secreting pituitary adenomas, hypointense T2-weighted ones showed higher IGF-1 levels, a smaller tumor size, less tumor invasiveness, and a better response to somatostatin analogue treatment [51].