Normal Pituitary Hypertrophy as a Frequent Cause of Pituitary Incidentaloma: A Follow-Up Study

Enlargement of the pituitary gland is a frequent cause of incidentaloma and of referrals to endocrinologists for hormonal evaluation and therapeutic advice. In neuroradiological series, 25–50% of healthy women who are 18–35 yr old have a convex superior pituitary contour, but pituitary height exceeds 9 mm in less than 0.5% of cases. This study was performed to provide thorough clinical and hormonal data and long-term endocrinological and imaging follow-up data on subjects with incidentally discovered pituitary hypertrophy (height > 9 mm). Seven eugonadal nulliparous women, 15–27 yr old, referred between 1989 and 1998 with incidentally diagnosed pituitary gland enlargement (height > 9 mm) and a suspected pituitary tumor, were studied. At presentation and at yearly intervals, PRL plasma levels and corticotropic, somatotropic, and thyrotropic pituitary function were measured; and pituitary dimensions and signal on magnetic resonance imaging (MRI), before and after iv gadolinium-diethylene-triamine-pentaaceti...