Endocrine Abstracts

Introduction: Cushing’s disease (CD) is a rare disorder caused by an ACTH-secreting pituitary adenoma. Transsphenoidal surgery (TSS) is the recommended first-line treatment. However, an equivocal or even normal preoperative MRI can preclude the surgical management and the outcome of these patients.

Objectives: Evaluate the relationship between preoperative MRI and TSS efficacy in patients with CD.

Methods: Retrospective cohort study of patients with CD followed in our centre between 1977 and 2013 (n=84). Patients who lost follow-up or with insufficient data on their personal records were excluded (n=51). Statistical analysis: SPSS (21).

Results: Thirty three patients, 29 (87.9%) women, with a median of 33 years (24–70) were included. All patients underwent TSS as first treatment option and were followed postoperatively during a median period of 8 years (1–28). Patients were divided in: Group A (n=19), cured patients; and Group B (n=14), patients with persistent (n=3) or recurrent (n=11) CD within a median of 12 months. No significant demographic and clinical differences were recorded between the two groups. Group B patients presented a greater frequency of non-diagnostic preoperative images (28.6 vs 10.5%). And, in patients with a precisely visualized pituitary lesion (n=27), those of Group A presented significant lower tumour diameters (8.4 vs 13.9 mm, P<0.01), a greater number of pituitary microadenoma (68.4 vs 35.7%, P<0.05), and none invasive macroadenoma (0% vs 21.4%) compared to Group B patients. All patients with non-diagnostic preoperative MRI (n=6) performed inferior petrosal sinus sampling (IPSS), with identification of lateralization of ACTH secretion in all patients (2/2) of Group A and one patient (1/4) of Group B. A pituitary adenoma (confirmed by pathological examination) was found in 84.2% patients of Group A but only in 50% of Group B.

Conclusions: Precise preoperative localisation of a corticotroph adenoma, particularly a microadenoma, in preoperative MRI was associated with a greater efficacy of TSS and a higher probability of cure. Performance of IPSS can be useful in patients with non-diagnostic preoperative MRI.