Endocrine Abstracts

Introduction: somatostatin analogs (SSA) are largely prescribed in acromegalic patients, whether as adjuvant or primary therapy. Response is variable and seems dependent of histological subtype. Intensity T2 signal in MRI has been related to granulation patern and accordingly with response to SSA.

Objective: To evaluate whether T2 MRI signal is correlated with effectiveness of SSA

Material and methods: Retrospective analysis of acromegalic patients treated with SSA and available T2 MRI. We considered response as complete (normal GH and IGF1), partial (GH and/or IGF1 reduction ≥50%) and no response (≤50%). MRI were analysed by one neuroradiologist blinded for clinical and pathological data. Visual assessment only or direct measurements of signal intensity using ROI cursors on T2 coronal sections classified adenomas as hypointense or hyperintense, according MRI signal ≤ temporal lobe white matter or ≥ grey matter, respectively. Signal intensity between grey and white matter defined isointensity.

Results: Fourteen patients (8 males) were treated with SSA for a minimum of 6 months. All but 5 patients were surgically treated (3 refused, 1 approach failed due to bleeding, 1 is waiting surgery). T2 MRI hypointensity was documented in 8 patients (group 1) and hyperintensity in 6 (group 2). Group 1 included 3 non responders, 3 with partial and 2 with complete response. Group 2 comprised 3 non responders, 2 with partial and 1 with complete response to SSA. Considering isolated GH reduction (≥ 50%), hypointensity was more often observed (62,5%).

Comments: In this cohort of acromegalic patients we observed no relationship between T2 signal intensity on MRI and hormonal response to SSA. One major limitation is the small sample analysed.