GROWTH PARTICULARS OF PITUITARY MACROADENOMAS WITH VARIOUS HORMONAL ACTIVITIES

Abstract

Background: Pituitary adenoma is not as infrequent as thought previously. The prevalence of macroadenomas in general population is up to 0.16–0.2%. Magnetic resonance imaging (MRI) is a method of choice in diagnosis of pituitary adenomas. Until now, specifics of imaging of pituitary adenomas with various hormonal activities have not been discussed.Aim: To analyze comparatively the size, volumes and growth direction in pituitary macroadenomas with various hormonal activities.Materials and methods: We analyzed MRI images of 305 patients with hypophyseal adenomas of more than 10 mm diameter, among them with non-functioning adenomas (n=109), prolactinomas (n=58), and somatotropinomas (n=138).Results: Depending on their hormonal activity, hypophyseal adenomas had different volumes (р<0.001): non-functioning hypophyseal adenomas had the volume of 6620 [2637; 14492] mm3 , prolactinomas – 5365 [1495; 10316] mm3 , somatotropinomas – 3052 [1696; 5727] mm3 . In the majority of patients from all groups, extrasellar growth at several directions was observed. Onedirectional growth was seen in 29% of non-functioning hypophyseal adenomas, 41% of prolactinomas and 37% of somatotropinomas (р>0.05). Non-functioning hypophyseal adenomas and prolactinomas demonstrated mostly suprasellar growth (in 83.5 and 79.3% of cases, respectively), whereas somatotropinomas were growing mostly in infrasellar direction (66.1%).Conclusion: These characteristic features of hypophyseal macroadenomas with various hormonal activities could be used for differential diagnosis, which may help to optimize patient assessment during the diagnostic work-up.

Keywords

• hypophyseal macroadenoma
• non-functioning hypophyseal adenoma
• prolactinoma
• somatotropinoma
• growth direction of hypophyseal adenoma