In a study that included 324 patients, MEN1-associated PITs were described as being larger (macroadenomas in 85 vs. 42% in sporadic cases), with more aggressive behavior (one third of MEN1-associated cases were observed to have invasive features), and reduced response to medical therapy (42 vs. 90% in sporadic cases), but without increased prevalence of pituitary carcinoma (146, 147, 151). The gene discussed is MEN1; the disease is pituitary adenocarcinoma.