Criteria for cure of acromegaly: a consensus statement

Clinical Profile and Treatment Outcomes in Patient with Acromegaly Using 14th Acromegaly Consensus Criteria

Introduction

Acromegaly is a chronic systemic disease characterized by excessive secretion of growth hormone (GH) and insulin-like growth factor 1 (IGF-1). This study reviews our experience with endoscopic transsphenoidal surgery (TSS) in acromegaly patients, focusing on remission rates according to the 2023 consensus criteria.

Methods

We conducted a hospital based, retrospective study involving 42 patients diagnosed with acromegaly who underwent endoscopic TSS, between January 2020 and June 2024. Clinical and hormonal profiles, comorbidities and outcome data were analysed. Remission was defined as age-adjusted IGF-1 levels 3 months post-surgery.

Results

Mean age at diagnosis was 36.43 ± 10.70 years. The two most frequent presenting symptoms were headache (64.28%) and visual deficits (47.61%). Common comorbidities included diabetes mellitus (23.8%) and hypertension (28.57%). Pre-operative hormonal evaluation revealed secondary hypogonadism in 41.66% of patients, followed by hypothyroidism (23.81%) and cortisol deficiency (21.43%). Biochemical remission was achieved in 18 out of 42 patients (42.85%), including all five patients with microadenomas and 35.13% of those with macroadenomas. Although Knosp grade, maximum tumour diameter and pre-operative post glucose growth hormone levels showed significant associations in univariate analyses, these associations were not significant after adjustment. On multivariate analysis, post-operative day 2 GH levels (≤2.75 ng/ml) emerged as a significant predictor of remission.

Conclusions

This study provides the comprehensive review of clinical presentations and outcomes of patients with acromegaly based on the latest acromegaly consensus guidelines. Notably, a post-operative day 2 GH less than 2.75 ng/ml emerged as a significant predictor of outcome.

IGF-I levels during standard Lanreotide dose predicts biochemical outcome of high-frequency regimen in acromegaly

INTRODUCTION

First-generation somatostatin receptor ligands (fg-SRLs) are the cornerstone of acromegaly treatment. Additional benefits were shown using high dose (HD) or high frequency (HF), relatively short-term regimens. Although several predictors of response to standard dose (SD)-fg-SRLs were reported, outcome biomarkers for HF administration are not yet available. Here, we aimed to identify predictors of response to long-term HF-fg-SRLs.

PATIENTS AND METHODS

A retrospective study was performed on 102 patients, treated with Lanreotide. Patients not controlled at 12 months of SD-Lanreotide (120 mg/28 days) were switched to HF-Lanreotide (120 mg/21 days) for additional 12 months.

RESULTS

Twenty-eight patients were controlled at 6 months of SD-Lanreotide (27.4%); 35 patients were controlled at 12 months of treatment (34.3%). Out of 67 patients treated with HF- Lanreotide, 18 (26.9%) were controlled at 6 months of treatment and remained controlled until 12 months. Both during SD and HF-Lanreotide administrations, IGF-I levels were reduced during the first six months of treatment (p < 0.001), without further significant reduction between 6 and 12 months of therapy. Response at 12 months of SD-Lanreotide was predicted by IGF-I reached at six months of SD-Lanreotide (p = 0.024). Response at 12 months of HF-Lanreotide treatment was predicted by IGF-I levels reached at six months of SD-Lanreotide treatment (p = 0.04) and six months of HF-Lanreotide treatment (p = 0.01).

CONCLUSION

Our results demonstrated that initial IGF-I levels during SD-Lanreotide predicted the biochemical outcome after 12 months of HF-Lanreotide. Patients in whom HF-Lanreotide did not normalize IGF-I after 6 months of treatment remained uncontrolled 12 months after starting this regimen.

Management policy for postoperative acromegaly patients with normal IGF-1 and high GH levels on oral glucose tests

PURPOSE

Acromegaly patients occasionally achieve either of the remission criterion of IGF-1 or GH level postoperatively; however, treatment for patients with discordant IGF-1 and GH levels remains unclear. This study aimed to clarify the clinical courses and features of postoperative patients with normal IGF-1 and high GH levels and support their management.

METHODS

Overall, 110 acromegaly patients underwent initial surgery and a 75-g oral glucose tolerance test (OGTT) 3 months postoperatively. Of the 110, 23 patients with normal IGF-1 and nadir GH levels of ≥ 0.4 µg/L on OGTT (high-GH group) were categorized into three subtypes based on their repeated examinations thereafter: late-remission type (nadir GH level on OGTT of < 0.4 µg/L later), recurrence type (elevated IGF-1 and GH levels later), and persistent type (normal IGF-1 levels and constantly high nadir GH levels on OGTTs).

RESULTS

Proportion of patients in the high-GH group was 23.6%, and they were distributed as follows: late-remission type (n = 10), recurrence type (n = 5), and persistent type (n = 8). There were significantly more women (P = 0.0178) than men in the late-remission type, and patients in the persistent type had significantly larger tumors (P = 0.0110) and higher preoperative GH levels (P = 0.0018) than those that achieved complete remission 3 months postoperatively.

CONCLUSION

Careful monitoring without additional medications is recommended at first in acromegaly patients with normal IGF-1 and high GH levels considering the possibility of recurrence in the future.

Novel approach to bone comorbidity in resistant acromegaly

Active acromegaly may lead to irreversible complications. Among them, acromegaly osteopathy and fragility (vertebral and hip) fractures have emerged as frequent and precocious events in the natural history of the disease, being correlated with longer disease duration and higher growth hormone (GH) levels, accounting for patients' reported poor quality of life, physical performance and other life-impacting complications. Differently from primary osteoporosis, bone mineral density is not a reliable tool to predict fracture risk in this clinical setting, as patients with active disease frequently have normal or slightly reduced bone mass; whereas bone quality is particularly compromised, as determined by low trabecular bone score (TBS) in patients with active disease as compared to healthy controls or patients with cured/controlled disease. The evidence of impaired bone microstructure has been profoundly investigated with different computed tomography (CT) techniques, reporting low trabecular number and thickness as well as wide but more porous cortical bone, providing an explanation for such a high prevalence of vertebral fractures (up to 40-50% in selected cohorts). Since data on bone-active drugs are scanty, disease control remains a cornerstone to prevent fractures. Nonetheless, some potential protective effects may derive from vitamin D supplementation and pasireotide therapies, independently from disease status. Aim of this manuscript is to review the current and emerging evidence on skeletal fragility in patients with active and resistant acromegaly.

Recurrence in acromegaly: two tertiary centers experience and review of the literature

BACKGROUND

Recurrence of acromegaly after successful surgery is a rare event, but no clear data are reported in the literature about its recurrence rates. This study aimed to evaluate the recurrence rate in a series of acromegalic patients treated by transsphenoidal surgery (TSS) with a long follow-up.

METHODS

We retrospectively analyzed data from 283 acromegalic patients who underwent TSS at two pituitary units in Milan (Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico and IRCCS Humanitas Research Hospital). The diagnosis and recurrence of acromegaly were defined by both elevated IGF-1 levels and a lack of GH suppression based on appropriate criteria for the assay used at the time of diagnosis.

RESULTS

After surgery, 143 patients (50%) were defined as not cured, 132 (47%) as cured and 8 (3%) as partially cured because of normalization of only one parameter, either IGF1 or GH. In the cured group, at the last follow-up (median time 86.8 months after surgery), only 1 patient (0.7%) showed full recurrence (IGF-1 + 5.61 SDS, GH nadir 1.27 µg/l), while 4 patients (3%) showed only increased IGF1. In the partially cured group at the last follow-up, 2/8 (25%) patients showed active acromegaly (IGF-1 SDS + 2.75 and + 3.62; GH nadir 0.6 and 0.5 µg/l, respectively).

CONCLUSIONS

In the literature, recurrence rates range widely, from 0 to 18%. In our series, recurrence occurred in 3.7% of patients, and in fewer than 1%, recurrence occurred with elevation of both IGF-1 and the GH nadir. More frequently (25%), recurrence came in the form of incomplete normalization of either IGF-1 or GH after surgery.

Empty sella in somatotropic pituitary adenomas; a series of 23 cases

Purpose

We aimed to investigate empty sella syndrome in somatotrophic pituitary adenoma for possible etiology, complications, and treatment options.

Method

Among over 2,000 skull base masses that have been managed in our center since 2013, we searched for growth hormone-producing adenomas. Clinical, surgical, and imaging data were retrospectively collected from hospital records to check for sella that lacked pituitary tissue on routine imaging.

Result

In 220 somatotrophic adenomas, 23 patients had an empty sella with surgical and follow-up data. The mean age of the sample was 46 years with the same male-to-female ratio. Five cases had partial empty sella and the rest were complete empty sellas. The most common simultaneous hormonal disturbance was high prolactin levels. Six had adenoma invasion into the clivus or sphenoid sinus and 10 had cavernous sinus intrusion. Peri-operative low-flow and high-flow cerebrospinal fluid (CSF) leaks were encountered in one and two patients, respectively, which were successfully sealed by abdominal fat. The majority of cases required growth hormone replacement therapy while it was controlled without any replacement therapy in nine patients. No pituitary hormonal disturbance occurred after transsphenoidal surgery except for hypothyroidism in one patient.

Conclusion

An empty sella filled with fluid can be detected frequently in pituitary adenomas, especially in the setting of acromegaly. The pituitary gland may be pushed to the roof of the sella and might be visible as a narrow rim on imaging or may be detected in unusual places out of the sella. The pathophysiology behind such finding originates from soft and hard tissue changes and CSF pressure alternations during abundant growth hormone production.

Consensus on criteria for acromegaly diagnosis and remission

PURPOSE

The 14th Acromegaly Consensus Conference was convened to consider biochemical criteria for acromegaly diagnosis and evaluation of therapeutic efficacy.

METHODS

Fifty-six acromegaly experts from 16 countries reviewed and discussed current evidence focused on biochemical assays; criteria for diagnosis and the role of imaging, pathology, and clinical assessments; consequences of diagnostic delay; criteria for remission and recommendations for follow up; and the value of assessment and monitoring in defining disease progression, selecting appropriate treatments, and maximizing patient outcomes.

RESULTS

In a patient with typical acromegaly features, insulin-like growth factor (IGF)-I > 1.3 times the upper limit of normal for age confirms the diagnosis. Random growth hormone (GH) measured after overnight fasting may be useful for informing prognosis, but is not required for diagnosis. For patients with equivocal results, IGF-I measurements using the same validated assay can be repeated, and oral glucose tolerance testing might also be useful. Although biochemical remission is the primary assessment of treatment outcome, biochemical findings should be interpreted within the clinical context of acromegaly. Follow up assessments should consider biochemical evaluation of treatment effectiveness, imaging studies evaluating residual/recurrent adenoma mass, and clinical signs and symptoms of acromegaly, its complications, and comorbidities. Referral to a multidisciplinary pituitary center should be considered for patients with equivocal biochemical, pathology, or imaging findings at diagnosis, and for patients insufficiently responsive to standard treatment approaches.

CONCLUSION

Consensus recommendations highlight new understandings of disordered GH and IGF-I in patients with acromegaly and the importance of expert management for this rare disease.

Thyroid Disorders in Saudi Patients With Acromegaly: A Tertiary Care Center Experience

Background Acromegaly is a rare disease that is frequently associated with thyroid diseases. The exact prevalence of goiter and thyroid dysfunction remains uncertain. Objectives This study aims to provide a comprehensive description of the clinical, morphological, and biochemical features of thyroid disorder in Saudi patients with acromegaly and to establish its correlation with the activity and duration of the disease. Methods This retrospective study involved patients who were diagnosed with acromegaly during the period 2006-2023 in an outpatient endocrine clinic at a tertiary hospital. Results A total of 40 patients with acromegaly (27 males and 13 females) were identified and included in the analysis, with a mean age of 46.78 ± 13.76 years and an estimated duration of disease of 8.08 ± 6.43 years. Goiter was diagnosed in 28 patients (70.0%), including multinodular goiter (MNG) (70.0%), solitary thyroid nodules (14.2%), and thyroid cysts (14.2%). Primary hypothyroidism was present at 40.0%. Goiter was not correlated with estimated insulin-like growth factor 1 (IGF-1) levels or disease duration. In 40 patients with nodular goiter, fine needle biopsies were performed in six cases; five nodules were benign, and one nodule was a follicular lesion of unknown significance (Bethesda III). Conclusions The patients with acromegaly have a high prevalence of nodular thyroid disorders and thyroid dysfunction. No cases of thyroid cancer were found in our study. The periodic ultrasonography assessment of the thyroid is needed for evaluating patients with acromegaly.

Control of acromegaly in more than 90% of patients after 10 years of pegvisomant therapy: an European referral centre real-life experience

PURPOSE

Pegvisomant (PEG) efficaciously controls IGF-I excess in acromegaly and possesses a positive impact on glucose metabolism. Data on very prolonged PEG treatment are still limited, therefore, we investigated the effects of 10-years PEG on disease control, maximal tumour diameter (MTD), and metabolic profile in consecutive patients resistant to somatostatin analogues (SRLs) followed in an European referral centre for acromegaly.

METHODS

Since the 2000s, we collected data on anthropometric, hormonal and metabolic parameters, and MTD of patients receiving PEG. In the current study, we included 45 patients (19 men, 26 women, 46.8 ± 11 years) treated for at least 5 years with PEG mono or combined therapy, analyzing data before, after 5- and 10-years PEG.

RESULTS

After10 years, 91% of patients showed full disease control and in 37% a significant decrease in MTD was found. Diabetes prevalence was slightly increased, whereas HbA1c remained stable over the decade. Transaminases remained stable and no case of cutaneous lipohypertrophy was recorded. A different metabolic impact between mono- or combined therapy was found. Patients in monotherapy showed significantly lower fasting glucose (p = 0.01), fasting insulin (p = 0.008), HbA1c (p = 0.007), HOMA-IR (p = 0.001), and significantly higher ISI₀ (p = 0.002), whereas patients under combined therapy showed significantly lower total (p = 0.03), and LDL cholesterol (p = 0.007). Acromegaly duration before PEG was inversely related to ΔFG (r = - 0.46, p = 0.03) and ΔFI (r = - 0.54, p = 0.05).

CONCLUSIONS

PEG is effective and safe in long term. In patients resistant to SRLs, early beginning of PEG allows a wider gluco-insulinemic improvement.

Caloric restriction as a possible pitfall for persistent acromegaly follow-up - case report

BACKGROUND

Acromegaly diagnosis is established when plasma levels of IGF-1 are increased and the Oral Glucose Tolerance Test (OGTT) with 75gr of glucose can't suppress Growth Hormone (GH) levels. These two parameters are also useful during follow-up, after surgical/radiologic therapy and/or during medical therapy.

CASE PRESENTATION

A 29-year-old woman was diagnosed with acromegaly after a severe headache. Previous amenorrhea and facial and acral changes were noticed. A pituitary macroadenoma was found, biochemical evaluation was in agreement with the suspected acromegaly and a transsphenoidal adenectomy was performed. As the disease recurred, a surgical reintervention and radiosurgery (Gamma Knife, 22 Gy) were necessary. No normalization of IGF-1 was achieved during three years after radiosurgery. Surprisingly, then, and although clinical features seemed getting worse, IGF-1 levels became consistently controlled to 0.3-0.8 times the upper limit of the reference range. Questioned, the patient referred that she was following an intermittent fasting dietary plan. However, based on the dietary questionnaire, she was found to be under severe caloric restriction. First OGTT (under caloric restriction) showed absence of GH suppression and an IGF-1 value of 234 ng/dL (Reference Range 76-286 ng/mL). A second OGTT, one month after an eucaloric diet was instituted, showed an increased IGF-1 of 294 ng/dL, maintaining an unsuppressed, yet less elevated, GH.

CONCLUSIONS

GHRH/GH/IGF-1 axis controls somatic growth. Regulation is complex, and nutrition status and feeding pattern have a recognized role. Like systemic inflammation or chronic liver disease, fasting and malnutrition decrease the expression of hepatic GH receptors, with consequent reduction of IGF-1 levels, through resistance to GH. This clinical report shows that caloric restriction may represent a pitfall in acromegaly follow-up.

[Treatment of acromegaly - data from the German Acromegaly Register]

Acromegaly is a rare disease in which chronic growth hormone overproduction (usually from an anterior pituitary adenoma) leads to various systemic complications. The management of acromegaly and the comorbidities of the disease is complex and requires a multidisciplinary approach. Early diagnosis is extremely important, as then the chances of a complete cure are significantly higher. The operation is the therapy of first choice and should be performed at a specialized center with an experienced neurosurgeon. With good patient information and guidance, the drug therapy of acromegaly patients in specialized practices and clinics can usually lead to biochemical control and thereby normalization of mortality risk. As with numerous rare diseases, care in specialized centers and recording and evaluation in registry studies can contribute to better patient care and the optimization of therapy and diagnostic guidelines. We assume that with the help of the German Acromegaly Registry, which currently includes more than 2500 patients with acromegaly, we will be able to present a realistic picture of the care situation in Germany in the coming years.

Gigantism: microsurgical treatment by transsphenoidal approach and prognostic factors

PURPOSE

We present the results of transsphenoidal microsurgical treatment in 14 patients with gigantism. The influence on the prognosis of factors such as the tumor size and preoperative levels of GH and IGF-1 is also quantified.

MATERIALS AND METHODS

The patients, operated between 1982 and 2004, were reviewed retrospectively in June 2022. All patients had complete endocrinological studies in the preoperative period and a postoperative control between 6 days and 3 weeks. Follow-up has been supported with annual check-ups between 3 and 31 years. We have compared the preoperative levels of GH and IGF-1 of these patients with the levels of a series of acromegalic patients operated on in the same Center.

RESULTS

In this series there were 4 women and 10 men. The age ranged between 14 and 21 years. In 6 patients, postoperative hormone levels achieved the disease control criteria (42.8%). The CT/MRI studies revealed the existence of invasive tumors in 10 of the patients (71.4%). Postoperative CT/MRI showed no tumor tissue in 3 patients but in 7 patients there were tumor remains. The remaining 4 patients had abnormal images although not considered as tumor. A statistical comparison of preoperative serum GH and IGF-1 levels in patients with gigantism and patients with acromegaly showed a significant elevation in the former.

CONCLUSION

Pituitary adenomas that cause gigantism are generally large and invasive, which makes them difficult to cure. High preoperative levels of GH and IGF-1 are also factors that decrease remission.

Resistance of neuroendocrine tumours to somatostatin analogs

INTRODUCTION

A common feature shared by most neuroendocrine tumors (NETs) is the expression on their surface of somatostatin receptors (SSTRs) that are essential for their pathophysiological regulation, diagnosis, and management. The first-generation synthetic somatostatin analogs (SSAs), octreotide and lanreotide, constitute the cornerstone of treatment for growth hormone secreting pituitary adenomas and functioning, progressive functioning, and non-functioning gastro-entero-pancreatic (GEP-NETs). SSAs exert their mechanism of action through binding to the SSTRs; however, their therapeutic response is frequently attenuated or diminished by the development of resistance. The phenomenon of resistance is complex implicating the presence of additional epigenetic and genetic mechanisms.

AREAS COVERED

We aim to analyze the molecular, genetic, and epigenetic mechanisms of resistance to SSA treatment. We also summarize recent clinical data related to the development of resistance on conventional and non-conventional modes of administration of the first-generation SSAs and the second-generation SSA pasireotide. We explore mechanisms used to counteract the resistance to SSAs using higher doses or more frequent mode of administration of SSAs and/or combination treatments.

EXPERT OPINION

There is considerable heterogeneity in the development of resistance to SSAs that is tumor-specific necessitating the delineation of the underlying pathophysiological processes to further expand their therapeutic applications.

Mean GH profile is more accurate than single fasting GH in the evaluation of acromegaly disease control during somatostatin receptor ligands therapy

PURPOSE

This study aims to compare the accuracy of mean GH profile (GHP) < 2.5 ng/ml and single fasting GH (SGH) < 1 ng/ml in the evaluation of disease control in acromegaly patients during somatostatin receptor ligands (SRLs) therapy.

METHODS

We retrospectively enrolled 100 acromegaly patients, 68 responder, and 32 partial responder to SRLs. Controlled disease has been defined as IGF-I levels within age-related normal limits, while partial response as pathological IGF-I values despite a reduction ≥ 50%. In all patients, GHP, SGH, IGF-I, and IGFBP-3 were evaluated.

RESULTS

Median GHP levels (1.2 ng/ml, IQR 0.5-2.3 ng/ml) were lower (p = 0.001) than SGH (1.9 ng/ml, IQR 1.0-3.6 ng/ml). Accuracy of GHP was 81%, whereas that of SGH was 55%, with a Kappa index of 0.520 and 0.237, respectively. In multivariable analysis GHP (p = 0.002) and IGFBP-3 (p = 0.004), but not SGH, were independently associated with normal IGF-I levels. At receiver-operator characteristic curve (ROC) analysis GHP cut-off sensitivity and specificity were 94.1% and 50.0%, respectively, while SGH sensitivity and specificity were 35.3% and 93.7%, respectively. Finally, in obese patients the GH cut-off level (both as SGH and GHP) associated to good disease control was significantly different with respect to not obese ones.

CONCLUSIONS

GHP associates with IGF-I (and therefore with appropriate control of disease) with higher accuracy than SGH. When GH evaluation is needed, the measurement of mean GHP should be preferred and use of BMI-related cut-offs is suggested.

Development and testing of diagnostic algorithms to identify patients with acromegaly in Southern Italian claims databases

Acromegaly is a rare disease characterized by an excessive production of growth-hormone and insulin-like growth factor 1, typically resulting from a GH-secreting pituitary adenoma. This study was aimed at comparing and measuring accuracy of newly and previously developed coding algorithms for the identification of acromegaly using Italian claims databases. This study was conducted between January 2015 and December 2018, using data from the claims databases of Caserta Local Health Unit (LHU) and Sicily Region in Southern Italy. To detect acromegaly cases from the general target population, four algorithms were developed using combinations of diagnostic, surgical procedure and co-payment exemption codes, pharmacy claims and specialist’s visits. Algorithm accuracy was assessed by measuring the Youden Index, sensitivity, specificity, positive and negative predictive values. The percentage of positive cases for each algorithm ranged from 7.9 (95% CI 6.4–9.8) to 13.8 (95% CI 11.7–16.2) per 100,000 inhabitants in Caserta LHU and from 7.8 (95% CI 7.1–8.6) to 16.4 (95% CI 15.3–17.5) in Sicily Region. Sensitivity of the different algorithms ranged from 71.1% (95% CI 54.1–84.6%) to 84.2% (95% CI 68.8–94.0%), while specificity was always higher than 99.9%. The algorithm based on the presence of claims suggestive of acromegaly in ≥ 2 different databases (i.e., hospital discharge records, copayment exemptions registry, pharmacy claims and specialist visits registry) achieved the highest Youden Index (84.2) and the highest positive predictive value (34.8; 95% CI 28.6–41.6). We tested four algorithms to identify acromegaly cases using claims databases with high sensitivity and Youden Index. Despite identifying rare diseases using real-world data is challenging, this study showed that robust validity testing may yield the identification of accurate coding algorithms.

Association of pre- and postoperative αKlotho levels with long-term remission after pituitary surgery for acromegaly

Soluble αKlotho (sKl) is a disease-specific biomarker that is elevated in patients with acromegaly and declines after surgery for pituitary adenoma. Approximately 25% of patients do not achieve remission after surgery, therefore a risk stratification for patients early in the course of their disease may allow for the identification of patients requiring adjuvant treatment. Growth hormone (GH) and insulin-like growth factor-1 (IGF-1) have been assessed as biomarker for disease activity, however the value of sKl as a predictive biomarker of surgical success has not been evaluated yet. In this study, we measured serum biomarkers before and after transsphenoidal pituitary surgery in 55 treatment-naïve patients. Based on biochemical findings at follow-up (7–16 years), we divided patients into three groups: (A) long-term cure (defined by normal IGF-1 and random low GH (< 1 μg/l) or a suppressed GH nadir (< 0.4/μg/l) on oral glucose testing); (B) initial remission with later disease activity; (C) persistent clinical and/or biochemical disease activity. sKl levels positively related to GH, IGF-1 levels and tumor volume. Interestingly, there was a statistically significant difference in pre- and postoperative levels of sKl between the long-term cure group and the group with persistent disease activity. This study provides first evidence that sKl may serve as an additional marker for surgical success, decreasing substantially in all patients with initial clinical remission while remaining high after surgery in patients with persistent disease activity.

Surgery for acromegaly: Indications and goals

Acromegaly is a disease that occurs secondary to high levels of GH, most often from a hormone-secreting pituitary adenoma, with multisystem adverse effects. Diagnosis includes serum GH and IGF-1 levels, and obtaining an MRI pituitary protocol to assess for a functional pituitary adenoma. Attempted gross total resection of the GH-secreting adenoma is the gold standard in treatment for patients with acromegaly for a goal of biochemical remission. Medical and radiation therapies are available when patients do not achieve biochemical cure after surgical therapy.

Influence of Disease Activity and Body Composition Parameters on Cross-Sectional Area of the Median Nerve in Acromegalic Patients

Carpal tunnel syndrome (CTS) is neuropathy that occurs due to compression of the median nerve in the carpal tunnel. Acromegaly is one of the important causes of CTS. The aim of this study was to examine median nerve with ultrasound in acromegalic patients and to assess the relationship with activity, duration of disease and body composition parameters. We prospectively examined the cross-sectional area (CSA) of the median nerve with high-resolution ultrasound in 107 acromegalic patients (70 females and 37 males) and 107 healthy controls (70 females and 37 males) matched for age, gender, and BMI. Body composition parameters were assessed by dual-energy X-ray absorptiometry (DXA). The Student t-tests and Pearson correlation were used for data analysis. The cross sectional area of the median nerve was increased in acromegalic patients compared to controls (11.9 ± 4.8 mm2 vs. 7.7 ± 2.4 mm2, P < 0.001). Positive correlation was found between IGF-1 levels and CSA in the acromegalic group (R = 0.400, P < 0.001). Relationship between CSA and duration of acromegaly was not confirmed. In acromegalic patients, BMI correlated with the CSA (R = 0.294, P = 0.002). There was no significant difference in BMI, fat mass between the acromegalic and control group, but lean mass was higher in acromegalic patients compared with controls (54.8 ± 13.3 vs. 51 ± 11.6, P = 0.047). Lean mass and LMI (total body lean mass/height) positively correlated with CSA in acromegalic patients (R = 0.340, P < 0.001; R = 0.424, P < 0.001). No correlation was observed between fat mass and CSA of median nerve in all groups. We confirmed the enlargement of the median nerve in acromegalic patients. This enlargement is proportional to the degree of IGF-1 levels and is not dependent on the duration of the disease. The enlargement of the median nerve in acromegalic patients also depends on lean body mass and is not dependent on fat body mass.

Influence of Disease Activity and Body Composition Parameters on Cross-Sectional Area of the Median Nerve in Acromegalic Patients

Carpal tunnel syndrome (CTS) is neuropathy that occurs due to compression of the median nerve in the carpal tunnel. Acromegaly is one of the important causes of CTS. The aim of this study was to examine median nerve with ultrasound in acromegalic patients and to assess the relationship with activity, duration of disease and body composition parameters. We prospectively examined the cross-sectional area (CSA) of the median nerve with high-resolution ultrasound in 107 acromegalic patients – control group (70 females and 37 males) and 107 healthy controls (70 females and 37 males) matched for age, gender, and BMI. Body composition parameters were assessed by dual-energy X-ray absorptiometry (DXA). The Student t-tests and Pearson correlation were used for data analysis. The cross sectional area of the median nerve was increased in acromegalic patients compared to controls (11.9±4.8 mm2 vs. 7.7±2.4 mm2, P<0.001). Positive correlation was found between IGF-1 levels and CSA in the acromegalic group (R = 0.400, P<0.001). Relationship between CSA and duration of acromegaly was not confirmed. In acromegalic patients, BMI correlated with the CSA (R=0.294, P=0.002). There was no significant difference in BMI, fat mass between the acromegalic and control group, but lean mass was higher in acromegalic patients compared with controls (54.8±13.3 vs. 51±11.6, P=0.047). Lean mass and LMI (total body lean mass/height) positively correlated with CSA in acromegalic patients (R=0.340, P<0.001; R=0.424, P<0.001). No correlation was observed between fat mass and CSA of median nerve in all groups. We confirmed the enlargement of the median nerve in acromegalic patients. This enlargement is proportional to the degree of IGF-1 levels and is not dependent on the duration of the disease. The enlargement of the median nerve in acromegalic patients also depends on lean body mass and is not dependent on fat body mass.

Long-term remission of acromegaly after somatostatin analogues withdrawal: a single-centre experience

PURPOSE

A long-lasting remission of acromegaly after somatostatin analogues (SAs) withdrawal has been described in some series. Our aim was to update the disease evolution after SAs withdrawal in a cohort of acromegalic patients.

METHODS

We retrospectively evaluated 21 acromegalic patients previously included in a multicentre study (Ronchi et al. 2008), updating data at the last follow-up. We added further 8 patients selected for SAs withdrawal between 2008-2018. Pituitary irradiation represented an exclusion criterion. The withdrawal was suggested after at least 9 months of clinical and hormonal disease control. Clinical and biochemical data prior and after SAs withdrawal were analysed.

RESULTS

In the whole cohort (29 patients) mean age was 50 ± 14.9 years and 72.4% were females. In 69% pituitary surgery was previously performed. Overall, the median time of treatment before SAs withdrawal was 53 months (IQR = 24-84). At the last follow up in 2019, 23/29 patients (79.3%) had a disease relapse after a median time of 6 months (interquartile range or IQR = 3-12) from the drug suspension, while 6/29 (20.7%) were still on remission after 120 months (IQR = 66-150). IGF-1 levels were significantly lower before withdrawal in patients with persistent remission compared to relapsing ones (IGF-1 SDS: -1.5 ± 0.6 vs -0.11 ± 1, p = 0.01). We did not observe any other difference between patients with and without relapse, including SAs formulation, dosage and treatment duration.

CONCLUSION

A successful withdrawal of SAs is possible in a subset of well-controlled acromegalic patients and it challenges the concept that medical therapy is a lifelong requirement.

Value of Early Post-Operative Growth Hormone Testing in Predicting Long-Term Remission and Residual Disease after Transsphenoidal Surgery for Acromegaly

INTRODUCTION

Surgical remission for acromegaly is dependent on a number of factors including tumour size, invasiveness, and surgical expertise. We studied the value of early post-operative growth hormone (GH) level as a predictor of outcome and to guide early surgical re-exploration for residual disease in patients with acromegaly.

METHODS

Patients with acromegaly undergoing first-time endoscopic transsphenoidal surgery between 2005 and 2015, in 2 regional neurosurgical centres, were studied. Insulin-like growth factor-1 (IGF-1), basal GH (i.e., sample before oral glucose), and GH nadir on oral glucose tolerance test (OGTT) were tested at various time points, including 2-5 days post-operatively. Definition of disease remission was according to the 2010 consensus statement (i.e., GH nadir <0.4 μg/L during an OGTT and normalized population-matched IGF-1). Forward stepwise logistic regression was used to determine factors associated with remission.

RESULTS

We investigated 81 consecutive patients with acromegaly, 67 (83%) of which had macroadenomas and 22 (27%) were noted to be invasive at surgery. Mean follow-up was 44 ± 25 months. Overall, surgical remission was achieved in 55 (68%) patients at final follow-up. On univariate analysis, the remission rates at the end of the study period for patients with early post-operative GH nadir on OGTT of <0.4 (N = 43), between 0.4 and 1 (N = 28), and >1 μg/L (N = 8) were 88, 54, and 20%, respectively. Similar results were seen with basal GH on early post-operative OGTT. On multivariate regression analysis, pre-operative IGF-1 (odds ratio of 13.1) and early post-operative basal GH (odds ratio of 5.0) and GH nadir on OGTT (odds ratio of 6.8) were significant predictors of residual disease. Based on a raised early GH nadir and post-operative MR findings, 10 patients underwent early surgical re-exploration. There was reduction in post-operative GH levels in 9 cases, of which 5 (50%) achieved long-term remission. There was an increased risk of new pituitary hormone deficiencies in patients having surgical re-exploration compared to those having a single operation (60 vs. 14%).

CONCLUSIONS

An early post-operative basal GH and GH nadir on OGTT are reliable predictors of long-term disease remission. It can be used to guide patients for early surgical re-exploration for residual disease, although there is increased risk of hypopituitarism.

Predictors for Remission after Transsphenoidal Surgery in Acromegaly: A Dutch Multicenter Study

CONTEXT

Transsphenoidal surgery (TSS) is the primary treatment of choice in acromegaly. It is important to identify patients in whom surgical cure is not attainable at an early stage, both to inform patients on expected treatment outcome and to select those who are more likely to need additional therapy.

OBJECTIVE

To identify predictors for remission after TSS in acromegaly.

METHODS

Large multicenter study with retrospective data collection from 3 tertiary neurosurgical referral centers in The Netherlands. We analyzed clinical data since 2000 from 3 cohorts (Groningen, Nijmegen, and Rotterdam, total n = 282). Multivariate regression models were used to identify predictors of early biochemical remission (12 weeks to 1 year postoperatively) according to the 2010 consensus criteria, long-term remission (age- and sex-normalized insulin-like growth factor 1 [IGF-1] and the absence of postoperative treatment until last follow-up), and relative IGF-1 and growth hormone [GH] reduction.

RESULTS

A larger maximum tumor diameter (odds ratio [OR] 0.91, 95% CI 0.87-0.96, P ≤ .0001) was associated with a lower chance of early biochemical remission. A larger maximum tumor diameter (OR 0.93, 95% CI 0.89-0.97, P = .0022) and a higher random GH concentration at diagnosis (OR 0.98, 95% CI 0.96-0.99, P = .0053) were associated with a lower chance of long-term remission.

CONCLUSION

Maximum tumor diameter and random GH concentration at diagnosis are the best predictors for remission after TSS in acromegaly.

Results from ACROCOVID: an international survey on the care of acromegaly during the COVID-19 era

With most global healthcare resources focused on COVID-19, altered resource allocation is disrupting the continuum of care for chronic endocrine conditions, including acromegaly. In order to assess the effects of COVID-19 on care of patients with acromegaly, we conducted an international online survey of endocrinologists. The questionnaire was drafted by a Steering Committee of acromegaly experts and covered both respondent demographics, contact and communication with patients, and patient care. Respondent awareness was generated through social media campaigns and the survey completed online using Google forms. The majority of endocrinologists who responded (N = 84) were based in Europe (67.9%) and were female (58.3%). Slightly more than half of respondents worked in a specialized pituitary center (52.4%) and a large minority cared for more than 50 acromegaly patients (47.6%). Most respondents (85.7%) indicated surgery was their first-line treatment, with only 14.3% indicating medical therapy as a first-choice treatment option. One-third (33.3%) of respondents reported having delayed a planned surgery due to a lack of COVID-19 testing provision and 54.8% due to a lack of surgical provision; 19.1% indicated that a lack of personal protective equipment had reduced their ability to treat patients with acromegaly. Just 21.4% of respondents reported no negative effects from the pandemic on diagnostic practice patterns, and just 19.1% reported no negative effect on patient follow-up practices. Many respondents (55.9%) indicated that remote methods had improved their ability to communicate with their patients and 69.0% indicated that they would continue to use methods of consultation necessitated by the COVID-19 pandemic. Our data suggest the COVID-19 pandemic is substantially affecting the care of acromegaly. However, these results also suggest that endocrinologists are embracing aspects of the 'new normal' to create a novel continuum of care better suited to the presumed post-COVID-19 environment. The goal of these changes must be both to improve care while shielding patients from more severe involvement in concomitant acute illnesses such COVID-19.

Vertebral Fractures Associated with Spinal Sagittal Imbalance and Quality of Life in Acromegaly: A Radiographic Study with EOS 2D/3D Technology

INTRODUCTION

Acromegaly is commonly complicated by arthropathy and skeletal fragility with high risk of vertebral fractures (VFs).

OBJECTIVE

This study aimed to assess whether VFs may be associated with sagittal spine deformities, arthropathy, impaired quality of life (QoL), pain, and disability.

METHODS

Thirty-eight patients with acromegaly (median age: 55 years, 20 males) and 38 matched control subjects were evaluated by a low-dose sagittal and coronal planes, X-ray imaging system (EOS®-2D/3D) for morphometric VFs, radiological signs of spine arthropathy, and spine deformities (Cobb thoracic index ≥40°, pelvic incidence minus lumbar lordosis ≥10°, pelvic tilt >20°, and sagittal vertical axis ≥4 cm) determining sagittal spine imbalance. Acromegalic patients were also evaluated by questionnaires for QoL (Acromegaly QoL Questionnaire [AcroQoL] and Short Form-36 [SF-36]) and pain and disability (Western Ontario and McMaster University [WOMAC]).

RESULTS

Acromegalic patients showed higher prevalence of thoracic hyperkyphosis (i.e., Cobb thoracic index ≥40°; p = 0.04) and pelvic tilt >20° (p = 0.02) than control subjects. VFs were found in 34.2% of acromegalic patients (p = 0.003 vs. control subjects), in relationship with higher prevalence of hyperkyphosis (p = 0.03), pelvic tilt >20° (p = 0.04), sagittal vertical axis ≥4 cm (p = 0.03), and moderate/severe subchondral degeneration (p = 0.01). Moreover, patients with VFs had lower AcroQoL general health (p = 0.007) and SF-36 general health (p = 0.002) scores and higher WOMAC pain (p = 0.003) and global (p = 0.009) scores than patients who did not fracture.

CONCLUSIONS

In acromegaly, VFs may be associated with spine deformities and sagittal imbalance, spine arthropathy, impaired QoL, and disability.

Multidisciplinary management of acromegaly: A consensus

The 13th Acromegaly Consensus Conference was held in November 2019 in Fort Lauderdale, Florida, and comprised acromegaly experts including endocrinologists and neurosurgeons who considered optimal approaches for multidisciplinary acromegaly management. Focused discussions reviewed techniques, results, and side effects of surgery, radiotherapy, and medical therapy, and how advances in technology and novel techniques have changed the way these modalities are used alone or in combination. Effects of treatment on patient outcomes were considered, along with strategies for optimizing and personalizing therapeutic approaches. Expert consensus recommendations emphasize how best to implement available treatment options as part of a multidisciplinary approach at Pituitary Tumor Centers of Excellence.

Maintenance of Acromegaly Control in Patients Switching From Injectable Somatostatin Receptor Ligands to Oral Octreotide

PURPOSE

The phase 3 CHIASMA OPTIMAL trial (NCT03252353) evaluated efficacy and safety of oral octreotide capsules (OOCs) in patients with acromegaly who previously demonstrated biochemical control while receiving injectable somatostatin receptor ligands (SRLs).

METHODS

In this double-blind study, patients (N = 56) stratified by prior SRL dose were randomly assigned 1:1 to OOC or placebo for 36 weeks. The primary end point was maintenance of biochemical control at the end of treatment (mean insulin-like growth factor 1 [IGF-1] ≤ 1.0 × upper limit of normal [ULN]; weeks 34 and 36). Time to loss of IGF-1 response and proportion requiring reversion to injectable SRLs were assessed as broader control measures.

RESULTS

Mean IGF-1 measurements were 0.80 and 0.97 × ULN for OOC and 0.84 and 1.69 × ULN for placebo, at baseline and end of treatment, respectively. Mean growth hormone (GH) changed from 0.66 to 0.60 ng/mL for OOCs and 0.90 to 2.57 ng/mL for placebo. Normalization of IGF-1 levels (≤ 1.0 × ULN) was maintained in 58.2% for OOCs vs 19.4% for placebo (P = .008); GH levels were maintained (< 2.5 ng/mL) in 77.7% for OOC vs 30.4% for placebo (P = .0007). Median time to loss of response (IGF-1 > 1.0 or ≥ 1.3 × ULN definitions) for patients receiving placebo was 16 weeks; for patients receiving OOCs, it was not reached for both definitions during the 36-week trial (P < .0001). Of the patients in the OOC group, 75% completed the trial on oral therapy. The OOC safety profile was consistent with previous SRL experience.

CONCLUSIONS

OOCs may be an effective therapy for patients with acromegaly who previously were treated with injectable SRLs.

Clinical features and therapeutic outcomes of patients with acromegaly in Saudi Arabia: a retrospective analysis

BACKGROUND

Acromegaly is a rare disease resulting in clinical sequelae with significant morbidity and mortality due to the central tumor mass effect and prolonged growth hormone (GH) hypersecretion.

OBJECTIVES

The goal is to describe the epidemiology, clinical features, presence of comorbidities, and treatment outcomes of acromegaly in Saudi Arabia.

METHODS

Data was collected through a retrospective review of the charts of all patients diagnosed with acromegaly from nine major hospitals in Saudi Arabia over a period of more than 25 years.

RESULTS

A total of 195 patients (116 males and 79 females), with a mean age at diagnosis of 43 ± 12 (males) and 46 ± 14 years (females), from nine major hospitals were identified and included in the analysis. All cases were caused by pituitary adenomas, of which 92.4% were macroadenomas. Headache, coarse facial features, acral growth, and sweating/oily skin were by far the most frequent presenting complaints. The most common comorbidities were diabetes mellitus (51.7%), followed by hypertension (50%) and visual field defect (30.5%). The vast majority (95%) of patients were treated surgically (98%). Twenty-four percent also received radiotherapy, and 74.4% received medical therapy. When stringent criteria were applied for assessment of outcomes of therapy, 28.7% of the patients were cured and 30.1% had their disease under control, while 28.7% were found to have active disease despite receiving multimodal therapy.

CONCLUSIONS

Our findings highlight the need for a national acromegaly registry to enable early identification, evaluation, and selection of the best therapeutic approaches to improve the outcome and remission rate of the disease.

Precision Therapy in Acromegaly Caused by Pituitary Tumors: How Close Is It to Reality?

Acromegaly presents with an enigmatic range of symptoms and comorbidities caused by chronic and progressive growth hormone elevations, commonly due to endocrinologic hypersecretion from a pituitary gland tumor. Comprehensive national acromegaly databases have been appearing over the years, allowing for international comparisons of data, although still presenting varying prevalence and incidence rates. Lack of large-scale analysis in geographical and ethnic differences in clinical presentation and management requires further research. Assessment of current and novel predictors of responsiveness to distinct therapy can lead to multilevel categorization of patients, allowing integration into new clinical guidelines and reduction of increased morbidity and mortality associated with acromegaly. This review compares current data from epidemiological studies and assesses the present-day application of prognostic factors in medical practice, the reality of precision therapy, as well as its future prospects in acromegaly, with a special focus on its relevance to the South Korean population.

Pasireotide for acromegaly: long-term outcomes from an extension to the Phase III PAOLA study

OBJECTIVE

In the Phase III PAOLA study (clinicaltrials.gov: NCT01137682), enrolled patients had uncontrolled acromegaly despite ≥6 months of octreotide/lanreotide treatment before study start. More patients achieved biochemical control with long-acting pasireotide versus continued treatment with octreotide/lanreotide (active control) at month 6. The current work assessed the extent of comorbidities at baseline and outcomes during a long-term extension.

DESIGN/METHODS

Patients receiving pasireotide 40 or 60 mg at core study end could continue on the same dose in an extension phase if biochemically controlled or receive pasireotide 60 mg if uncontrolled. Uncontrolled patients on active control were switched to pasireotide 40 mg, with the dose increased at week 16 of the extension if still uncontrolled (crossover group). Efficacy and safety are reported to 304 weeks (~5.8 years) for patients randomized to pasireotide (core + extension), and 268 weeks for patients in the crossover group (extension only).

RESULTS

Almost half (49.5%; 98/198) of patients had ≥3 comorbidities at core baseline. During the extension, 173 patients received pasireotide. Pasireotide effectively and consistently reduced GH and IGF-I levels for up to 5.8 years' treatment; 37.0% of patients achieved GH <1.0 µg/L and normal IGF-I at some point during the core or extension. Improvements were observed in key symptoms. The long-term safety profile was similar to that in the core study; 23/173 patients discontinued treatment because of adverse events.

CONCLUSIONS

In this patient population with a high burden of comorbid illness, pasireotide was well tolerated and efficacious, providing prolonged maintenance of biochemical control and improving symptoms.

Random Gh and Igf-I levels after transsphenoidal surgery for acromegaly: relation with long-term remission

PURPOSE

To evaluate the role of IGF-I and random GH measurements 3 months after transsphenoidal surgery (TSS) in predicting long-term remission in acromegaly patients.

METHODS

Retrospective analysis of 54 acromegaly patients who underwent TSS with the same neurosurgery team. Random GH and IGF-I values evaluated 3 months after TSS were related to long-term outcomes. The initiation of adjuvant therapy at any time defined surgical failure.

RESULTS

At 3 months, 14 (25.9%) patients had controlled disease (CD; normal IGF-I and GH < 1.0 µg/L), 25 (46.3%) had uncontrolled disease (UD; high IGF-I and GH), and 15 (27.8%) had biochemical discrepancies (BD): 12 BDI (normal IGF-I + GH ≥ 1.0 μg/L) and 3 BDII (high IGF-I + GH < 1.0 μg/L). All patients of the CD group, 2 of the UD, 11 of the BDI, and 2 of the BDII, progressed with long-term remission and had IGF-I ≤ 1.25-fold the Upper Limit of Normal (ULN), in contrast with all cases of surgical failure where IGF-I was ≥1.3-fold ULN. Only one patient with normal IGF-I had recurrence, resulting in 100% sensitivity and 96% specificity of post-surgical IGF-I ≤ 1.25-fold ULN to predict long-term remission, observed in 54% of our cohort. Post-surgical random GH ≥ 1.7 µg/L was the best cutoff to identify surgical failure, but its accuracy to predict long-term outcomes was limited.

CONCLUSIONS

IGF-I levels ≤ 1.25-fold ULN 3 months after TSS was the best guide for long-term remission in acromegaly patients with both initial surgical failure and discrepant biochemical results.

Staging and managing patients with acromegaly in clinical practice: baseline data from the SAGIT® validation study

PURPOSE

The SAGIT® instrument, designed to assist clinicians to stage acromegaly, assess treatment response and adapt patient management, was well received by endocrinologists in a pilot study. We report an interim analysis of baseline data from the validation phase.

METHODS

The SAGIT® validation study (ClinicalTrials.gov NCT02539927) is an international, non-interventional study. Data collection included: demographic/disease characteristics; medical/surgical histories; concomitant acromegaly treatments; investigators' subjective evaluation of disease-control status (clinical global evaluation of disease control [CGE-DC]; controlled/not controlled/yet to be clarified) and clinical disease activity (active/not active); growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels; investigators' therapeutic decision.

RESULTS

Of 228 patients enrolled, investigators considered disease to be controlled in 110 (48.2%), not controlled in 105 (46.1%), and yet to be clarified in 13 (5.7%) according to CGE-DC. Thirty-three patients were treatment-naïve (not controlled, n = 31; yet to be clarified, n = 2). Investigators considered 48.2% patients in the controlled and 95.2% in the not-controlled groups to have clinically active disease. In the controlled group, 29.7% of patients did not exhibit hormonal control (GH ≤ 2.5 µg/L; normalized IGF-1) and 47.3% did not have rigorous hormonal control (GH < 1.0 µg/L; normalized IGF-1) by contemporary consensus. Current acromegaly treatment was continued with no change for 91.8% of patients in the controlled and 40.0% in the not-controlled groups.

CONCLUSIONS

These data highlight discrepancies between investigator-evaluated disease-control status, disease activity, hormonal control, and treatment decisions in acromegaly. Once validated, the SAGIT® instrument may assist clinicians in making active management decisions for patients with acromegaly.

Safety and efficacy of repeat radiosurgery for acromegaly: an International Multi-Institutional Study

PURPOSE

Surgical resection is the first line treatment for growth hormone (GH) secreting tumors. Stereotactic radiosurgery (SRS) is recommended for patients who do not achieve endocrine remission after resection. The purpose of this study was to evaluate safety and efficacy of repeat radiosurgery for acromegaly.

METHODS

Three hundred and ninety-eight patients with acromegaly treated with the Gamma Knife radiosurgery (Elekta AB, Stockholm) were identified from the International Gamma Knife Research Foundation database. Among these, 21 patients underwent repeated SRS with sufficient endocrine follow-up and 18 patients had sufficient imaging follow-up. Tumor control was defined as lack of adenoma progression on imaging. Endocrine remission was defined as a normal IGF-1 concentration while off medical therapy.

RESULTS

Median time from initial SRS to repeat SRS was 5.0 years. The median imaging and endocrine follow-up duration after repeat SRS was 3.4 and 3.8 years, respectively. The median initial marginal dose was 17 Gy, and the median repeat marginal dose was 23 Gy. Of the 18 patients with adequate imaging follow up, 15 (83.3%) patients had tumor control and of 21 patients with endocrine follow-up, 9 (42.9%) patients had endocrine remission at last follow-up visit. Four patients (19.0%) developed new deficits after repeat radiosurgery. Of these, 3 patients had neurologic deficits and 1 patient had endocrine deficit.

CONCLUSIONS

Repeat radiosurgery for persistent acromegaly offers a reasonable benefit to risk profile for this challenging patient cohort. Further studies are needed to identify patients best suited for this type of approach.

[Evaluation of transsphenoidal adenomectomy outcomes in acromegaly using different remission criteria]

For a long time, surgical removal of somatotropinoma using the transsphenoidal approach has been the first stage of treatment in most acromegaly patients. For the past decades, the efficacy criteria for surgical treatment of acromegaly have significantly changed, which requires appropriate correction.

PURPOSE

We aimed to evaluate the results of transsphenoidal adenomectomy in acromegaly patients using various criteria for disease remission.

MATERIAL AND METHODS

The study included patients with newly diagnosed acromegaly who underwent transnasal transsphenoidal endoscopic adenomectomy performed by a single neurosurgeon. The surgical treatment outcomes were evaluated 6 months after operative intervention based on levels of IGF-1, OGTT, and GH. The obtained data were analyzed using different threshold values for the level of GH nadir during OGTT: criteria A <2.0 ng/ml, criteria B <1.0 ng/ml, and criteria C <0.4 ng/ml to assess acromegaly remission, along with matching of the IGF-1 level to the reference range for a given gender and age.

RESULTS

The study included 70 patients (52 females and 18 males) with a mean age of 52.2±11.5 years (29 to 73 years). The baseline IGF-1 level exceeded the upper limit of the reference range 3.3±1.4 (1.1-7.3)-fold, on average. The baseline mean basal GH level was 34.2±41.7 (1.2-192.0) ng/ml. The mean pituitary adenoma size was 16.7±8.6 (4.3-46.0) mm; 18 (26%) out of 70 patients had pituitary microadenoma, and 52 (74%) patients had macroadenoma. Six months after surgery, acromegaly remission met criteria A in 47 (67%) patients, criteria B in 28 (40%) patients, and criteria C in 18 (26%) patients.

CONCLUSION

Our findings demonstrate that evaluation of transsphenoidal adenomectomy outcomes in treatment of acromegaly patients depends on the criteria chosen for assessing remission. This feature should be considered when comparing outcomes of surgical treatment for acromegaly in different years. Probably, introduction of the 2010 criteria should be accompanied by revision of the previous remission indicators.

Effect of combined treatment with a pan-PI3K inhibitor or an isoform-specific PI3K inhibitor and everolimus on cell proliferation in GH-secreting pituitary tumour in an experimental setting

PURPOSE

PI3K/Akt/mTOR pathway activation is common in GH-secreting pituitary tumours, and a target for treatment with mTOR inhibitors, including everolimus (EVE). The current study aimed to evaluate the efficacy of two PI3K inhibitors (PI3Ki), NVP-BKM120 and NVP-BYL719, alone and in combination with EVE in rat GH-secreting pituitary tumour cell line (GH3) and human GH-secreting pituitary tumour cell cultures.

METHODS

In GH3 cell line and in six GH-secreting tumour cell cultures, the effects of PI3Ki and EVE, as single agents and in combination, were tested on cell viability and colony survival, by MTT and clonogenic assay, respectively, whereas western blot was performed to evaluate the underlying intracellular signalling pathways.

RESULTS

PI3Ki and EVE showed a dose-dependent inhibition of cell viability in GH3 cell line, with PI3Ki displaying a synergistic effect when combined with EVE. PI3Ki and EVE inhibited colony survival in GH3 cell line with no further improvement in combination. In GH-secreting pituitary tumour cell cultures PI3Ki are effective in inhibiting cell viability increasing the slight and non significant inhibition induced by EVE as single agent, generally showing a synergistic effect. Despite in both GH3 cell line and GH-secreting pituitary tumour cell cultures combination of PI3Ki enhanced EVE effect, the study of intracellular signalling pathways revealed a different regulation of PI3K/Akt/mTOR and MAPK between the two models.

CONCLUSIONS

The results of the current study demonstrated that PI3Ki, especially in combination with EVE, are effective in inhibiting cell proliferation, therefore representing a promising therapeutic tool for the treatment of aggressive GH-secreting pituitary tumours, not responsive to standard medical therapies.

A Consensus Statement on acromegaly therapeutic outcomes

The 11th Acromegaly Consensus Conference in April 2017 was convened to update recommendations on therapeutic outcomes for patients with acromegaly. Consensus guidelines on the medical management of acromegaly were last published in 2014; since then, new pharmacological agents have been developed and new approaches to treatment sequencing have been considered. Thirty-seven experts in the management of patients with acromegaly reviewed the current literature and assessed changes in drug approvals, clinical practice standards and clinical opinion. They considered current treatment outcome goals with a focus on the impact of current and emerging somatostatin receptor ligands, growth hormone receptor antagonists and dopamine agonists on biochemical, clinical, tumour mass and surgical outcomes. The participants discussed factors that would determine pharmacological choices as well as the proposed place of each agent in the guidelines. We present consensus recommendations highlighting how acromegaly management could be optimized in clinical practice.

Growth hormone: isoforms, clinical aspects and assays interference

The measurement of circulating concentrations of growth hormone (GH) is an indispensable tool in the diagnosis of both GH deficiency and GH excess. GH is a heterogeneous protein composed of several molecular isoforms, but the physiological role of these different isoforms has not yet been fully understood. The 22KD GH (22 K-GH) is the main isoform in circulation, followed by 20KD GH (20 K-GH) and other rare isoforms. Studies have been performed to better understand the biological actions of the different isoforms as well as their importance in pathological conditions. Generally, the non-22 K- and 20 K-GH isoforms are secreted in parallel to 22 K-GH, and only very moderate changes in the ratio between isoforms have been described in some pituitary tumors or during exercise. Therefore, in a diagnostic approach, concentrations of 22 K-GH accurately reflect total GH secretion. On the other hand, the differential recognition of GH isoforms by different GH immunoassays used in clinical routine contributes to the known discrepancy in results from different GH assays. This makes the application of uniform decision limits problematic. Therefore, the worldwide efforts to standardize GH assays include the recommendation to use 22 K-GH specific GH assays calibrated against the pure 22 K-GH reference preparation 98/574. Adoption of this recommendation might lead to improvement in diagnosis and follow-up of pathological conditions, and facilitate the comparison of results from different laboratories.

Postoperative Changes in Metabolic Parameters of Patients with Surgically Controlled Acromegaly: Assessment of New Stringent Cure Criteria

The criteria for surgical cure of acromegaly have become more stringent during the past decades and a change from Cortina to new consensus criteria has recently been proposed. However, the superiority of the new consensus over Cortina criteria with respect to postoperative metabolic parameters remains to be ascertained. We retrospectively assessed metabolic parameters, the body habitus, and other health-related parameters of 48 patients with surgically controlled acromegaly who met the Cortina criteria [normalized insulin-like growth factor-1 (IGF-1) level and nadir growth hormone (GH) level <1.0 ng/ml during postoperative oral glucose tolerance test]. The 48 patients were divided into two groups. Group A (n = 33) met the new consensus criteria (normalized IGF-1 and nadir GH level <0.4 ng/ml). Group B (n = 15) met Cortina criteria, but their nadir GH ranged from 0.4 to 1.0 ng/ml. In both groups, the level of triglyceride and homeostasis model assessment-insulin resistance (HOMA-IR) was significantly decreased 1 year after the operation (P < 0.05). High-density lipoprotein cholesterol showed a significant increase only in group B (P = 0.02). However, the two groups did not differ with respect to the postoperative improvement rate of these parameters and the other health-related parameters including body mass index, blood pressure, anterior pituitary function, and self-estimated quality of life scale. In conclusion, our findings show that with respect to changes in metabolic parameters and the body habitus assessed 1 year after surgery, the stricter consensus criteria seemed not to be superior to Cortina criteria.

Trends in surgery, hospital admissions and imaging for pituitary adenomas in Australia

PURPOSE

There is a paucity of epidemiological information on treatment and imaging of pituitary adenomas in Australia.

METHODS

Australian data on pituitary surgery, hospital admissions for pituitary adenomas, and pituitary imaging on patients 15 years and over were obtained from administrative databases between 2000/2001 and 2014/2015. Changes over time and by age and sex were assessed.

RESULTS

In 2014/15 there were 37.7 pituitary procedures/million population, corresponding to a 35.4% (p < 0.05) increase over the 2000/2001 rate. Overall, most (87.2%) procedures were partial excisions of pituitary gland via transsphenoidal surgery (TSS). Admissions for acromegaly increased from 7.1/million in 2000/2001 to 17.2/million in 2003/2004 and then decreased to 6.5/million in 2014/2015. The average age-adjusted rate of pituitary imaging over the study period was 689.6/million/year, which increased significantly (p < 0.05). There was a significant increase in pituitary MRIs (p < 0.05) and a significant decline in pituitary CTs (p < 0.05). Surgical procedure rates were correlated with the pituitary imaging rates (r = 0.62, p < 0.05).

CONCLUSION

Pituitary surgery rates increased between 2000/2001 and 2014/2015. The most common procedure was partial excision of the pituitary gland via TSS. Admissions for pituitary neoplasms increased over the study while admissions for acromegaly rose to their highest rate in 2003/2004 and then decreased. There was a substantial increase in the rate of pituitary imaging, which may have resulted in increased detection of pituitary incidentalomas. The underlying reasons for the increased rate of pituitary surgery, and the non-sustained increased rate of admissions for acromegaly are unclear and warrant further investigation.

Microsurgical versus endoscopic transsphenoidal resection for acromegaly: a systematic review of outcomes and complications

PURPOSE

The aim of this systematic review is to evaluate the long-term endocrine outcomes and postoperative complications following endoscopic vs. microscopic transsphenoidal resection (TSR) for the treatment of acromegaly.

METHODS

A literature review was performed, and studies with at least five patients who underwent TSR for acromegaly, reporting biochemical remission criteria and long-term remission outcomes were included. Data extracted from each study included surgical technique, perioperative complications, biochemical remission criteria, and long-term remission outcomes.

RESULTS

Fifty-two case series from 1976 to 2016 met the inclusion criteria, comprising 4375 patients. Thirty-six reports were microsurgical (n = 3144) and 13 were endoscopic (n = 940). Three studies compared microsurgical (n = 111) to endoscopic TSR outcomes (n = 180). The overall initial and long-term remission rates were 58.2 vs. 57.4% and 69.2 vs. 70.2% for the microsurgical and endoscopic groups, respectively. For microadenomas, the initial and long-term remission rates were 77.6 vs. 82.2% and 76.9 vs. 73.5% for microsurgical and endoscopic approaches, respectively. For macroadenomas, the initial and long-term remission rates were 46.9 vs. 60.0% and 40.2 vs. 61.5% for microsurgical and endoscopic approaches, respectively. The rates of postoperative CSF leak were 3.0 vs. 2.3% for the microscopic and endoscopic groups, respectively. The rates of hypopituitarism and transient diabetes insipidus were 6.7 vs. 6.4% and 9.0 vs. 7.8% for the microscopic and endoscopic groups, respectively.

CONCLUSIONS

Both endoscopic and microsurgical approaches for TSR of growth hormone-secreting adenomas are viable treatment options for patients with acromegaly, and yield similarly high rates of remission under the most current consensus criteria.

Clinical characteristics of acromegalic patients with empty sella and their outcomes following transsphenoidal surgery

PURPOSE

To analyze the clinical characteristics of acromegalic patients with empty sella (ES, herniation of the subarachnoid space within the sella turcica) and the impact of ES on transsphenoidal surgery in such patients.

METHODS

Seventy-eight patients, newly diagnosed with acromegaly who underwent transsphenoidal surgery were included. ES was defined as the pituitary gland and adenoma occupying less than 50% of the sella turcica on midsagittal magnetic resonance (MR) imaging.

RESULTS

Twelve patients (15.4%), predominantly female (10 women, p = .047), had ES in preoperative MR imaging. ES patients had smaller mean tumor diameter (6.3 mm) than non-ES patients (11.2 mm, p = .001). In preoperative MR imaging, occult adenoma was found in three (25%) ES and three (4.5%) non-ES patients (p = .044). Intraoperative cerebrospinal fluid (CSF) leakage was more frequent in the ES patients than in the non-ES patients (58.3 vs. 25.8%, p = .024). This led to an increased rate of sellar floor reconstruction using abdominal fat and/or postoperative lumber drainage in the ES patients (ES: 41.7 vs. non-ES: 16.7%, p = .063). Endocrinological remission after surgery was more frequent in the non-ES patients (72.7%) than in the ES patients (58.3%) (p = .248).

CONCLUSIONS

Co-existence of acromegaly with ES is not rare, and is associated with occult adenoma, intra/postoperative CSF leakage, and a worse endocrinological outcome after transsphenoidal surgery; although, the underlying mechanism remains unclear.

Pegvisomant in acromegaly: an update

BACKGROUND

In 2007, we published an opinion document to review the role of pegvisomant (PEG) in the treatment of acromegaly. Since then, new evidence emerged on the biochemical and clinical effects of PEG and on its long-term efficacy and safety.

AIM

We here reviewed the emerging aspects of the use of PEG in clinical practice in the light of the most recent literature.

RESULTS

The clinical use of PEG is still suboptimal, considering that it remains the most powerful tool to control IGF-I in acromegaly allowing to obtain, with a pharmacological treatment, the most important clinical effects in terms of signs and symptoms, quality of life and comorbidities. The number of patients with acromegaly exposed to PEG worldwide has become quite elevated and the prolonged follow-up allows now to deal quite satisfactorily with many clinical issues including major safety issues, such as the concerns about possible tumour (re)growth under PEG. The positive or neutral impact of PEG on glucose metabolism has been highlighted, and the clinical experience, although limited, with sleep apnoea and pregnancy has been reviewed. Finally, the current concept of somatostatin receptor ligands (SRL) resistance has been addressed, in order to better define the acromegaly patients to whom the PEG option may be offered.

CONCLUSIONS

PEG increasingly appears to be an effective and safe medical option for many patients not controlled by SRL but its use still needs to be optimized.

Daily life reflections of acromegaly guidelines

PURPOSE

To determine the differences in acromegaly diagnosis, treatment, and follow-up among Turkish endocrinologists, and to investigate how the published guidelines are applied in clinical practice.

METHODS

The questionnaire was formatted as an electronic survey, conducted between November and December 2015, and sent weekly for 6 weeks via e-mail to 528 endocrinologists in Turkey.

RESULTS

The questionnaire was answered by 37.4 % of endocrinologists. Insulin-like growth factor-1 and nadir growth hormone level after 75 g oral glucose tolerance test (nadir GH-OGTT) were the most commonly preferred methods for the initial diagnosis. A total of 49.5 % of the participants reported using preoperative medical therapy (MT) either routinely or on a case-to-case basis. Somatostatin analogs were the most commonly used drugs, both in pre- and postoperative MT. Disease activity following surgery was assessed in the 3rd postoperative month using IGF-1 levels. Similarly, IGF-1 monitoring was preferred in the follow-up period. Monitoring nadir GH-OGTT levels was the most commonly used method in the assessment of discordant test results. The dose titration was done at month 3 after the start of MT. Resistance to SRLs was considered after using the maximal dose for at least 6 months. Pegvisomant was generally used in second- and third-line therapy. Similarly, cabergoline was not preferred in monotherapy by the majority of participants. Radiotherapy was considered in patients with incomplete response to surgery and medical treatments.

CONCLUSIONS

Although there were subtle differences, clinical practice guidelines were usually followed among Turkish endocrinologists.

Effects of long-term combined treatment with somatostatin analogues and pegvisomant on cardiac structure and performance in acromegaly

To date, no data are available on the effects of long-term combined treatment with somatostatin analogues (SA) and pegvisomant (PEG) on cardiovascular complications in acromegaly. The current study aimed at investigating the effects of long-term SA + PEG on cardiac structure and performance. Thirty-six patients (14 M, 22 F, aged 52.3 ± 10.2 years) entered this study. Weight, BMI, systolic (SBP) and diastolic (DBP) blood pressure, IGF-I, fasting glucose (FG), fasting insulin (FI), HOMA-IR, HbA_1c, and lipids were evaluated at baseline (T0), after long-term (median 36 months) SA (T1), after 12 (T12) and 60 (T60) months of SA + PEG, and at last follow-up (LFU, median 78 months). At each time point, all patients underwent echocardiography. At T1, induced a slight but not significant decrease in IGF-I (p = 0.077), whereas FI (p = 0.004), HOMA-IR (p = 0.013), ejection fraction (EF, p = 0.013), early (E) to late (A) ventricular filling velocities (E/A, p = 0.001), and isovolumetric relaxation time (IVRT, p = 0.000) significantly improved. At T12, IGF-I (p = 0.000) significantly reduced compared to T0, and FI (p = 0.001), HOMA-IR (p = 0.000), LVMI (p = 0.000), and E/A (p = 0.006) further improved compared to T1. At T60, FI (p = 0.027), HOMA-IR (p = 0.049), and E/A (p = 0.005) significantly improved as compared to T1. At LFU IGF-I normalized in 83.3 %, FI (p = 0.000), HOMA-IR (p = 0.000), LVMi (p = 0.000), and E/A (p = 0.005) further improved as compared to T1. PEG dose significantly correlated with LVMi at T12 (r = 0.575, p = 0.000) and T60 (r = 0.403, p = 0.037). Long-term PEG addition to SA improves cardiac structure and performance, particularly diastolic dysfunction, in acromegalic patients resistant to SA.

Biochemical investigations in diagnosis and follow up of acromegaly

Measurements of human growth hormone (GH) and insulin-like growth-factor I (IGF-I) are cornerstones in the diagnosis of acromegaly. Both hormones are also used as biochemical markers in the evaluation of disease activity during treatment. Management of acromegaly is particularly challenging in cases where discordant information is obtained from measurement of GH concentrations following oral glucose load and from measurement of IGF-I. While in some patients biological factors can explain the discrepancy, in many cases issues with the analytical methods seem to be responsible. Assays used by endocrine laboratories to determine concentrations of GH and IGF-I underwent significant changes during the last decades. While generally leading to more sensitive and reproducible methods, these changes also had considerable impact on absolute concentrations measured. This must be reflected by updated decision limits, cut-offs and reference intervals. Since different commercially available assays do not agree very well, method specific interpretation of GH and IGF-I concentrations is required. This complexity in the interpretation of hormone concentrations is not always appropriately reflected in laboratory reports, but also not in clinical guidelines reporting decision limits not related to a specific analytical method. The present review provides an overview about methodological and biological variables affecting the biochemical assessment of acromegaly in diagnosis and follow up.

Carotid artery protrusion and dehiscence in patients with acromegaly

PURPOSE

Acromegaly is a systemic disease which causes multiple bony alterations. Some authors reported that acromegalic patients have risk factors for an intraoperative vascular injury due to the specific anatomical features of their sphenoid sinus. The objective of our study was to analyze the anatomic characteristics of sphenoid sinus in acromegalic patients compared with controls, by evaluation of computed tomography (CT) findings.

METHODS

We examined 45 acromegalic (acromegaly group) and 45 non-acromegalic patients (control group) with pituitary adenomas who were matched for sex, age, height, tumor size, and cavernous sinus invasion (Knosp grade). Preoperative CT of the pituitary region including the sphenoid sinus was used to evaluate the following anatomic characteristics: type of sphenoid sinus (sellar or pre-sellar/conchal); intrasphenoid septa (non/single or multiple); carotid artery protrusion; carotid artery dehiscence; intercarotid distance.

RESULTS

Sixteen acromegalic patients (35.5 %) and 6 controls (13.3 %) had carotid artery protrusion. Additionally, 10 acromegalic patients (22.2 %) and 3 controls (6.6 %) had carotid artery dehiscence. Carotid artery protrusion and dehiscence were more frequent in the acromegaly group than in control group (p = 0.013 and 0.035, respectively). Other anatomic characteristics (type of sphenoid sinus, intrasphenoid septa, and intracarotid distance) showed no significant differences between acromegaly and control groups.

CONCLUSIONS

Our study suggests that carotid artery protrusion and dehiscence occur more frequently among acromegalic patients, compared with non-acromegalic patients. It is important for surgeons to be aware of these anatomic variations to avoid vital complications, such as carotid injuries, during surgery.

Surgical management of acromegaly: Long term functional outcome analysis and assessment of recurrent/residual disease

Context:

Functional growth hormone producing adenomas have long-term deleterious effects on the visual apparatus, the cardiovascular and musculoskeletal systems, and often predispose to malignancies. Since persistence of acromegaly affects outcome and quality of life, therapeutic interventions become mandatory.

Aim:

This study represents an analysis of long-term clinical and endocrinal outcome of 115 patients of acromegaly after surgical management.

Setting and Design:

Tertiary care retrospective study.

Materials and Methods:

One hundred and fifteen patients (male:female ratio: 1:1.09) with acromegalic features were studied. Apart from acromegalic features, their main clinical presentation also included headache, diminution of vision, field defects, ptosis, irregular menstruation, diabetes insipidus, diabetes mellitus and hypertension. Six of them presented with apoplexy. Their preoperative endocrinal evaluation included basal and suppressed growth hormone (GH), prolactin and thyroid levels. On the basis of axial and coronal CT scan or multiplanar MR imaging or both, the tumors were classified according to their suprasellar and parasellar extension (Hardy's grade). Transnasal trans-sphenoidal surgery (TSS) (n = 37) and sublabial, rhinoseptal TSS (n = 72) were the preferred approaches. Six patients with significant parasellar extensions underwent trans-cranial explorations. The patients were followed up at 6 and 12 weeks and then at 6 monthly intervals. Hormonal and CT/MR evaluation were also done. Attainment of random GH value less than 2.5 µg/L, and the nadir GH value after oral glucose tolerance test (OGTT) less than 1 µg/L were used as the criteria of cure.

Findings:

The patients were preoperatively in Hardy's tumor grade 0 (29), A (21), A+E (3), B (21), B+E (5), C (9), C+E (10), D (1) D+E (11), E (5), respectively. One hundred and one patients were available for follow-up (FU; median FU duration: 84 months; range: 6 to 132 months). Surgical cure was achieved in 73 patients following the first surgery; and, in 10 additional patients following a second intervention. No patient with a preoperative grade 0, A, B, C had a recurrence after attaining the initial remission. Recurrence after an initial cure occurred in 7 patients (overall remission rate following surgery: 75.24%). The preoperative grade of the latter patients was A+E:1, B+E:1, C+E:1, D:1, D+E:2, E:1, respectively. All these patients underwent subsequent radiotherapy (RT). The twelve patients with persistent symptoms and high GH levels following surgery underwent RT; six others with improved symptoms despite high GH levels were kept under strict observation. There was no surgical mortality.

Conclusions:

A high remission rate without significant morbidity could be achieved following surgical intervention in acromegalic patients. Following surgery, tumors with greater than or equal to 3 cm suprasellar height and without parasellar extension had no clinical recurrence at FU. A continuous monitoring is mandatory to pick up relapsed cases as well as those who develop delayed signs of hypopituitarism. A subset of patients who show clinical improvement following surgery but still have higher GH levels may be followed up without additional therapy unless clinical signs reappear or the serum GH levels progressively increase.

Mononostril versus Binostril Endoscopic Transsphenoidal Approach for Pituitary Adenomas: A Systematic Review and Meta-Analysis

Background

Over the past several decades, the endoscopic endonasal transsphenoidal approach (EETA) has gradually become a preferred option of pituitary adenomas surgery because of its minimal invasiveness and high efficiency. However, some EETA operations were performed through one nostril (mononostril), while other EETA operations were performed through both nostrils (binostril). Therefore, we conducted this study to compare the pros and cons of these two methods in an attempted to confirm which method is more effective.

Methods

We executed a systematic literature search of PubMed, the Cochrane Library, and the Web of Science and Medline (1992–2015). The language is limited to English and all studies should meet the inclusion criteria. Comparisons were made for postoperative outcomes, complications, and other relevant parameters between the mononostril and the binostril group. Statistical analyses of categorical variables were undertaken by the use of Stata 12.0 and SPASS 19.0.

Results

Thirty studies, involving 4805 patients, were included. The two groups had similar results in GTR rate (included GTR rate of macroadenomas), hormonal remission rate, improvement in visual function, postoperative CSF leak, permanent diabetes insipidus, meningitis, and sinusitis. The binostril group had less temporary diabetes insipidus (2.9% vs. 5.3%, p = 0.022), less anterior pituitary insufficiency (2.3% vs. 6.4%, p = 0.000) and few hospitalization days (3.2 days vs. 4.4 days, p<0.05) than the mononostril group. However, the mononostril group had less rate of epistaxis (0.4% vs. 1.5%, p = 0.008) than the binostril group. For invasive macroadenomas, the binostril group seem to demonstrate a tendency towards better outcomes though there was no subgroup analysis between the two groups.

Conclusion

The binostril approach had less temporary diabetes insipidus, anterior pituitary insufficiency, and a shorter length of hospital stay, although they demonstrated a higher rate of epistaxis than the mononstril group. Additionally, the binostril group seemed to suggest a tendency towards better outcomes for invasive macroadenomas.

Switching patients with acromegaly from octreotide to pasireotide improves biochemical control: crossover extension to a randomized, double-blind, Phase III study

BACKGROUND

Many patients with acromegaly do not achieve biochemical control with first-generation somatostatin analogues. A large, multicenter, randomized, Phase III core study demonstrated that pasireotide LAR had significantly superior efficacy over octreotide LAR. This analysis explores the efficacy and safety of switching therapeutic arms in inadequately controlled patients during a 12-month crossover extension.

METHODS

Patients with inadequate biochemical control (GH ≥2.5 μg/L and/or IGF-1 > ULN) at end of core study (month 12) were eligible to switch to pasireotide LAR 40 mg/28 days (n = 81) or octreotide LAR 20 mg/28 days (n = 38). One dose escalation to pasireotide LAR 60 mg/28 days or octreotide LAR 30 mg/28 days was permitted, but not mandatory, at month 17 or 20.

RESULTS

Twelve months after crossover, 17.3 % of pasireotide LAR and 0 % of octreotide LAR patients achieved GH <2.5 μg/L and normal IGF-1 (main outcome measure); 27.2 and 5.3 % of pasireotide LAR and octreotide LAR patients achieved normal IGF-1, respectively; 44.4 and 23.7 % of pasireotide LAR and octreotide LAR patients achieved GH <2.5 μg/L, respectively. Mean (±SD) tumor volume further decreased from the end of the core study by 25 % (±25) and 18 % (±28); 54.3 % of pasireotide LAR and 42.3 % of octreotide LAR patients achieved significant (≥20 %) tumor volume reduction during the extension. The safety profile of pasireotide LAR was similar to that of octreotide LAR, with the exception of the frequency and degree of hyperglycemia-related adverse events.

CONCLUSIONS

Pasireotide LAR is a promising treatment option for patients with acromegaly inadequately controlled with the first-generation somatostatin analogue octreotide LAR.

TRIAL REGISTRATION

clinicaltrials.gov, NCT00600886 . Registered 14 January 2008.