Glucose metabolism outcomes after pituitary surgery in patients with acromegaly.

AIM: To investigate the impact of pituitary surgery on glucose metabolism and to identify predictors of remission of diabetes after pituitary surgery in patients with acromegaly. METHODS: A national multicenter retrospective study of patients with acromegaly undergoing transsphenoidal surgery for the first time at 33 tertiary Spanish hospitals (ACRO-SPAIN study) was performed. Surgical remission of acromegaly was evaluated according to the 2000 and 2010 criteria. RESULTS: A total of 604 acromegaly patients were included in the study with a total median follow up of 91 months (interquartile range [IQR] 45-163). At the acromegaly diagnosis, 23.8% of the patients had diabetes mellitus (DM) with a median glycated hemoglobin (HbA1c) of 6.9% (IQR 6.4-7.9) [51.9 mmol/mol (IQR 46.4-62.8)]. In the multivariate analysis, older age (odds ratio [OR] 1.02, 95% CI 1.00-1.05), dyslipidemia (OR 5.25, 95% CI 2.81 to 9.79), arthropathy (OR 1.39, 95% CI 2.82 to 9.79), and higher IGF-I levels (OR 1.30, 95% CI 1.05 to 1.60) were associated with a greater prevalence of DM. At the last follow-up visit after surgery, 21.1% of the DM patients (56.7% of them with surgical remission of acromegaly) experienced diabetes remission. The cure rate of DM was more common in older patients (hazard ratio [HR] 1.77, 95% CI 1.31 to 2.43), when surgical cure was achieved (HR 2.10, 95% CI 1.01 to 4.37) and when anterior pituitary function was not affected after surgery (HR 3.38, 95% CI 1.17 to 9.75). CONCLUSION: Glucose metabolism improved in patients with acromegaly after surgery and 21% of the diabetic patients experienced diabetes remission; being more frequent in patients of older age, and those who experienced surgical cure and those with preserved anterior pituitary function after surgery.

Pegvisomant and pasireotide in PRL and GH co-secreting vs GH-secreting Pit-NETs.

The objective of the study was to evaluate the efficacy of second-line therapies in patients with acromegaly caused by a growth hormone (GH) and prolactin (PRL) co-secreting pituitary neuroendocrine tumor (GH&PRL-Pit-NET) compared to their efficacy in patients with acromegaly caused by a GH-secreting pituitary neuroendocrine tumor (GH-Pit-NET). This is a multicenter retrospective study of patients with acromegaly on treatment with pasireotide and/or pegvisomant. Patients were classified in two groups: GH&PRL-Pit-NETs when evidence of hyperprolactinemia and immunohistochemistry (IHC) for GH and PRL was positive or if PRL were >200 ng/dL regardless of the PRL-IHC and GH-Pit-NETs when the previously mentioned criteria were not met. A total of 28 cases with GH&PRL-Pit-NETs and 122 with GH-Pit-NETs met the inclusion criteria. GH&PRL-Pit-NETs presented at a younger age, caused hypopituitarism, and were invasive more frequently than GH-Pit-NETs. There were 124 patients treated with pegvisomant and 49 with pasireotide at any time. The efficacy of pegvisomant for IGF-1 normalization was of 81.5% and of pasireotide of 71.4%. No differences in IGF-1 control with pasireotide and with pegvisomant were observed between GH&PRL-Pit-NETs and GH-Pit-NETs. All GH&PRL-Pit-NET cases treated with pasireotide (n = 6) and 82.6% (n = 19/23) of the cases treated with pegvisomant normalized PRL levels. No differences in the rate of IGF-1 control between pegvisomant and pasireotide were detected in patients with GH&PRL-Pit-NETs (84.9% vs 66.7%, P = 0.178). We conclude that despite the more aggressive behavior of GH&PRL-Pit-NETs than GH-Pit-NETs, no differences in the rate of IGF-1 control with pegvisomant and pasireotide were observed between both groups, and both drugs have shown to be effective treatments to control IGF-1 and PRL hypersecretion in these tumors.

Differences between GH and PRL co-secreting and GH-secreting pituitary adenomas. A series of 604 cases.

PURPOSE: To evaluate differences in clinical presentation and in surgical outcomes between growth hormone-secreting pituitary adenomas (GH-PAs) and GH and prolactin co-secreting pituitary adenomas (GH&PRL-PAs). METHODS: Multicenter retrospective study of 604 patients with acromegaly submitted to pituitary surgery. Patients were classified into two groups according to serum PRL levels at diagnosis and immunohistochemistry (IHC) for PRL: a) GH&PRL-PAs when PRL levels were above the upper limit of normal and IHC for GH and PRL was positive or PRL levels were >100ng/and PRL IHC was not available (n=130) and b) GH-PAs who did not meet the previously mentioned criteria (n=474). RESULTS: GH&PRL-PAs represented 21.5% (n=130) of patients with acromegaly. The mean age at diagnosis was lower in GH&PRL-PAs than in GH-PAs (P<0.001). GH&PRL-PAs were more frequently macroadenomas (90.6% vs. 77.4%, P=0.001) and tended to be more invasive (33.6% vs. 24.7%, P=0.057) than GH-PAs. Furthermore, they had presurgical hypopituitarism more frequently (OR 2.8, 95% CI 1.83-4.38). IGF-1 upper limit of normality (ULN) levels at diagnosis were lower in patients with GH&PRL-PAs (median 2.4 [IQR 1.73-3.29] vs. 2.7 [IQR 1.91-3.67], P=0.023). There were no differences in the immediate (41.1% vs 43.3%, P=0.659) or long-term post-surgical acromegaly biochemical cure rate (53.5% vs. 53.1%, P=0.936) between groups. However, there was a higher incidence of permanent arginine-vasopressin deficiency (AVP-D) (7.3% vs. 2.4%, P=0.011) in GH&PRL-PAs patients. CONCLUSIONS: GH&PRL-PAs are responsible for 20% of acromegaly cases. These tumors are more invasive, larger and cause hypopituitarism more frequently than GH-PAs and are diagnosed at an earlier age. The biochemical cure rate is similar between both groups, but patients with GH&PRL-PAs tend to develop permanent postsurgical AVP-D more frequently.