Magnetic resonance imaging as a predictor of therapeutic response to pasireotide in acromegaly.

OBJECTIVE: Hyperintensity signal in T2-weighted magnetic resonance imaging (MRI) has been related to better therapeutic response during pasireotide treatment in acromegaly. The aim of the study was to evaluate T2 MRI signal intensity and its relation with pasireotide therapeutic effectiveness in real-life clinical practice. DESIGN, PATIENTS AND MEASUREMENTS: Retrospective multicentre study including acromegaly patients treated with pasireotide. Adenoma T2-weighted MRI signal at diagnosis was qualitatively classified as iso-hyperintense or hypointense. Insulin-like growth factor (IGF-I), growth hormone (GH) and tumour volume reduction were assessed after 6 and 12 months of treatment and its effectiveness evaluated according to baseline MRI signal. Hormonal response was considered 'complete' when normalization of IGF-I levels was achieved. Significant tumour shrinkage was defined as a volume reduction of ≥25% from baseline. RESULTS: Eighty-one patients were included (48% women, 50 ± 1.5 years); 93% had previously received somatostatin receptor ligands (SRLs) treatment. MRI signal was hypointense in 25 (31%) and hyperintense in 56 (69%) cases. At 12 months of follow-up, 42/73 cases (58%) showed normalization of IGF-I and 37% both GH and IGF-I. MRI signal intensity was not associated with hormonal control. 19/51 cases (37%) presented a significant tumour volume shrinkage, 16 (41%) from the hyperintense group and 3 (25%) from the hypointense. CONCLUSIONS: T2-signal hyperintensity was more frequently observed in pasireotide treated patients. Almost 60% of SRLs resistant patients showed a complete normalization of IGF-I after 1 year of pasireotide treatment, regardless of the MRI signal. There was also no difference in the percentage tumour shrinkage over basal residual volume between the two groups.

Integrative clinical, hormonal, and molecular data associate with invasiveness in acromegaly: REMAH study.

INTRODUCTION: Growth hormone (GH)-secreting pituitary tumors (GHomas) are the most common acromegaly cause. At diagnosis, most of them are macroadenomas, and up to 56% display cavernous sinus invasion. Biomarker assessment associated with tumor growth and invasion is important to optimize their management. OBJECTIVES: The study aims to identify clinical/hormonal/molecular biomarkers associated with tumor size and invasiveness in GHomas and to analyze the influence of pre-treatment with somatostatin analogs (SSAs) or dopamine agonists (DAs) in key molecular biomarker expression. METHODS: Clinical/analytical/radiological variables were evaluated in 192 patients from the REMAH study (ambispective multicenter post-surgery study of the Spanish Society of Endocrinology and Nutrition). The expression of somatostatin/ghrelin/dopamine system components and key pituitary/proliferation markers was evaluated in GHomas after the first surgery. Univariate/multivariate regression studies were performed to identify association between variables. RESULTS: Eighty percent of patients harbor macroadenomas (63.8% with extrasellar growth). Associations between larger and more invasive GHomas with younger age, visual abnormalities, higher IGF1 levels, extrasellar/suprasellar growth, and/or cavernous sinus invasion were found. Higher GH1 and lower PRL/POMC/CGA/AVPR1B/DRD2T/DRD2L expression levels (P < .05) were associated with tumor invasiveness. Least Absolute Shrinkage and Selection Operator's penalized regression identified combinations of clinical and molecular features with areas under the curve between 0.67 and 0.82. Pre-operative therapy with DA or SSAs did not alter the expression of any of the markers analyzed except for DRD1/AVPR1B (up-regulated with DA) and FSHB/CRHR1 (down-regulated with SSAs). CONCLUSIONS: A specific combination of clinical/analytical/molecular variables was found to be associated with tumor invasiveness and growth capacity in GHomas. Pre-treatment with first-line drugs for acromegaly did not significantly modify the expression of the most relevant biomarkers in our association model. These findings provide valuable insights for risk stratification and personalized management of GHomas.

Use of lanreotide in combination with cabergoline or pegvisomant in patients with acromegaly in the clinical practice: The ACROCOMB study.

PURPOSE: To describe real-world use of lanreotide combination therapy for acromegaly. PATIENTS AND METHODS: ACROCOMB is a retrospective observational Spanish study of patients with active acromegaly treated with lanreotide combination therapy between 2006 and 2011. 108 patients treated at 44 Spanish Endocrinology Departments were analyzed separately: 61 patients received lanreotide/cabergoline (cabergoline cohort) and 47 lanreotide/pegvisomant (pegvisomant cohort). RESULTS: Patient median age was 50.8 years in the cabergoline cohort and 42.7 years in the pegvisomant cohort. Prior medical treatments were somatostatin analogue (SSA) monotherapy (40 [66%] patients) or dopamine agonists (7 [11%] patients) in the cabergoline cohort and SSA (29 [62%] patients) or pegvisomant monotherapy (16 [34%] patients) in the pegvisomant cohort. Across both cohorts 12 patients were previously untreated, and prior therapy was unknown/missing in 4 patients. Median duration of combined treatment was 1.6 years (0.1-6) and 2.1 years (0.4-6.3) in the cabergoline and pegvisomant cohorts, respectively. At baseline, median insulin growth factor (IGF)-I values were 149% upper limit of normal (ULN) (15-505%) in the cabergoline cohort and 156% ULN (15-534%) in the pegvisomant cohort, and decreased to 104% ULN (13-557%) p<0.001 and 86% ULN (23-345%) p<0.0001, respectively, at end of study (EOS). Normal age-adjusted values of IGF-I were obtained in 48% of lanreotide/cabergoline-treated patients and 70% of lanreotide/pegvisomant-treated patients at EOS. There were no significant changes in hepatic, cardiac or glycaemic parameters in either cohort. CONCLUSION: In clinical practice lanreotide treatment combinations are useful options for patients with acromegaly when monotherapy is insufficient; particularly, the combination of lanreotide and pegvisomant in patients not controlled with either SSA or pegvisomant alone has high efficacy and is well-tolerated.