Could different treatment approaches in acromegaly influence life expectancy? A comparative study between Bulgaria and Campania (Italy)

The changing landscape of acromegaly - an epidemiological perspective

Acromegaly is a rare disease and thus challenging to accurately quantify epidemiologically. In this comprehensive literature review, we compare different approaches to studying acromegaly from an epidemiological perspective and describe the temporal evolution of the disease pertaining to epidemiological variables, clinical presentation and mortality. We present updated epidemiological data from the population-based Danish cohort of patients with acromegaly (AcroDEN), along with meta-analyses of existing estimates from around the world.Based on this, we conclude that the incidence, prevalence and age at acromegaly diagnosis are all steadily increasing, but with considerable variation between studies. An increased number of incidental cases may contribute to the increase in incidence and age at diagnosis, respectively. The clinical features at presentation are trending toward a milder disease phenotype at diagnosis, and advances in therapeutic options have reduced the mortality of patients with acromegaly to a level similar to that of the general population. Moreover, the underlying cause of death has shifted from cardiovascular to malignant neoplastic diseases.

Investigational drugs for the treatment of acromegaly: new agents to transform therapy

INTRODUCTION

Disease control is essential to decrease morbidity burden and mortality in acromegaly patients. In the last decades, the availability of new drugs increased the rate of disease control. However, up to 55% of patients remain uncontrolled despite available treatment strategies in real-world data. The reasons for this finding may include poor adherence, inadequate tolerability, therapeutic inertia, and high costs. Since acromegaly is a chronic disease and medical therapy is usually life-long, patient's adherence to treatment is fundamental in both achieving and maintaining disease control. Less invasive routes of administration could improve adherence and concur to increase disease control rate.

AREAS COVERED

The aim of current review is to provide a detailed update about investigational drugs for acromegaly treatment currently under investigation as paltusotine, ONO-5788, AP102, GT-02037, ISIS 766720, CAM2024, Lanreotide PRF, DP1038, MTD201, solid dose injection of octreotide.

EXPERT OPINION

Medical therapy of acromegaly is an evolving field. Current studies are addressing patient's need for both new molecules and less invasive routes of administration for already existing drugs. It cannot be ruled out that drugs currently used for other diseases such as cancer could be considered in the future for the treatment of acromegaly.

Long-term Efficacy and Safety of Pasireotide in Patients With Acromegaly: 14 Years of Single-Center Real-World Experience

CONTEXT

Acromegaly is a rare, chronic, debilitating disorder caused by prolonged hypersecretion of growth hormone (GH) and overproduction of insulin-like growth factor I (IGF-I). Medical therapies, including the somatostatin receptor ligand (SRL) pasireotide, are frequently used to restore biochemical control.

OBJECTIVE

As patients often receive therapy over prolonged periods, long-term data from real-life settings are needed.

METHODS

A retrospective analysis was performed using a prospectively maintained database of all patients with acromegaly from our primary care center who were enrolled in clinical studies with pasireotide (first visit November 2008). The main outcome measures were safety and biochemical control (age-adjusted IGF-I ≤ upper limit of normal).

RESULTS

Patients (n = 50) entered 4 parental studies and 30 continued in the rollover; at data cutoff (June 2022), 27 were still receiving pasireotide. Overall, median (range) exposure was 58 (3-137) months. Normal IGF-I was achieved in 54%, and acromegaly symptoms and quality of life were improved with treatment. No predictors of pasireotide response were identified; however, controlled patients had smaller tumors and lower GH at baseline. Tumor volume reduction occurred in 63% of evaluable patients (n = 10/16). Most patients presented hyperglycemic events, including 63.2% of patients with normal glucose before treatment. Older patients and those with higher IGF-I, glucose, and HbA1c at baseline had higher glucose and HbA1c during pasireotide treatment.

CONCLUSION

Pasireotide provided clinical benefit and was well tolerated for more than 11 years of treatment in acromegaly patients, most of whom were resistant to first-generation SRLs.

Real World Data on the Epidemiology, Diagnosis, and Treatment of Acromegaly: A Registries-based Approach

INTRODUCTION

Despite the inherent heterogeneity of the information derived from national registries, they are a useful tool to investigate the epidemiological, clinical, biochemical and treatment outcome characteristics of low prevalence conditions such as acromegaly. Although the information provided by single-center experiences is more homogeneous, these studies usually comprise a limited number of patients and thus, frequently lack statistical power.

AREAS COVERED

Registry-based Information regarding the epidemiology, clinical presentation, biochemical and imaging diagnosis, as well as therapeutic outcome and mortality in acromegaly is critically analyzed.

EXPERT OPINION

By gathering data from multiple centers in a specific Country, these registries generate important insights into the real-life behavior of this condition, that should be considered, both, in international consensus meetings and in the design of local, Country-specific diagnostic and therapeutic strategies.

"Subclinical atherosclerosis in acromegaly: Possible association with cardiovascular risk factors rather than disease activity"

OBJECTIVE

Cardiovascular (CV) disease is still a major cause of excessive morbidity and mortality in patients with active acromegaly, which may be attributed to a high prevalence of associated pro-atherosclerotic risk factors. However, a direct effect of GH/IGF-1 excess on the vasculature has been previously suggested, warranting further investigation. The present study was designed to investigate whether chronic GH/IGF-1 excess is associated with an increased prevalence of subclinical atherosclerosis in patients with acromegaly.

DESIGN

We measured carotid intima-media thickness (cIMT) and assessed carotid plaques by ultrasonography along with classical CV risk factors in 54 acromegaly patients (34 females, 50 ± 12 years and compared those with 62 (42 females, 53 ± 13 years) age-, sex- and CV risk factors- matched controls. In order to compare cIMT measurements between patients and controls we analyzed common carotid artery far wall data as well as a combined measurement result, which consisted of the mean value of the six different measurements, three at each side.

RESULTS

mean ± SD serum GH and IGF-1 levels were 2.76 ± 4.65 ng/mL and 1.7 ± 1.25 x ULN, respectively, in all acromegaly patients. Age, body mass index, blood pressure, lipid levels, fasting glucose and Framingham's global cardiovascular risk score classification were similar comparing patients and controls. Combined median [IQR] cIMT measurements were similar in acromegaly patients and matched controls (0.59 [0.52-0.66] mm vs. 0.59 [0.52-0.69] mm; P = 0.872) as well as in acromegaly patients with active and controlled disease (0.59 [0.51-0.68] mm vs. 0.60 [0.54-0.68] mm; P = 0.385). No significant correlations were observed between cIMT measurements and GH (Spearman r = 0.1, P = 0.49) or IGF-1 (Spearman r = 0.13, P = 0.37) levels in patients with acromegaly. Carotid atherosclerotic plaques prevalence was similar in patients and controls (26% vs. 32%; P = 0.54) as well as in patients with active and controlled acromegaly (22% vs. 30%; P = 0.537).

CONCLUSIONS

Our data suggest that GH/IGF-1 excess itself is not one of the main drivers of subclinical morphological atherosclerosis changes in patients with acromegaly and that optimal control of acromegaly-associated CV risk factors may preserve vasculature structure even when strict biochemical control is not achieved.

Pituitary tumors and the risk of other malignancies: is the relationship coincidental or causal?

Pituitary adenomas are benign neoplasms of the pituitary. The most prevalent are prolactinomas and non-functioning pituitary adenomas, followed by growth hormone- and ACTH-secreting adenomas. Most pituitary adenomas seem to be sporadic and their persistent growth is very atypical. No molecular markers predict their behavior. The occurrence of pituitary adenomas and malignancies in the same patient can be either pure coincidence or caused by shared underlying genetic susceptibility involved in tumorigenesis. Detailed family history on cancers/tumors in the first, second and third generation of family members on each side of the family has been reported in a few studies. They found an association of pituitary tumors with positive family history for breast, lung and colorectal cancer. We have reported that in about 50% of patients with pituitary adenomas, an association with positive family history for cancer has been found independent of secretory phenotype (acromegaly, prolactinoma, Cushing's disease or non-functioning pituitary adenomas). We also found earlier onset of pituitary tumors (younger age at diagnosis of pituitary tumors) in patients with a strong family history of cancer. In our recent unpublished series of 1300 patients with pituitary adenomas, 6.8% of patients were diagnosed with malignancy. The latency period between the diagnosis of pituitary adenoma and cancer was variable, and in 33% of patients, it was longer than 5 years. Besides the inherited trophic mechanisms (shared underlying genetic variants), the potential influence of shared complex epigenetic influences (environmental and behavioral factors - obesity, smoking, alcohol intake and insulin resistance) is discussed. Further studies are needed to better understand if patients with pituitary adenomas are at increased risk for cancer.

Acromegaly: Clinical Care in Central and Eastern Europe, Israel, and Kazakhstan

Acromegaly is a rare condition typically caused by benign pituitary adenomas, resulting in excessive production of growth hormone. Clinical manifestations of acromegaly are diverse, varying from the overgrowth of body tissue to cardiovascular, metabolic, and osteoarticular disorders. Symptoms may emerge slowly, overlapping with other diseases and often involve many different healthcare specialists. In the last decade, efforts to provide an accurate and timely diagnosis of acromegaly have improved disease management and clinical experience. Despite this progress, marked differences in the diagnosis, treatment, and management of acromegaly exist from country-to-country. To address these inconsistencies in the region comprising Central and Eastern Europe, Israel, and Kazakhstan, a panel of acromegaly experts from 13 of these countries was convened. Acromegaly experts from each country provided available information on the approaches from their country, including regional treatment centers and multidisciplinary teams, treatment access, reimbursement and availability, and physician education, disease awareness, and patient advocacy. Across several areas of acromegaly management, divergent approaches were identified and discussed, including the provision of multidisciplinary care, approved and available treatments, and disease awareness programs. These were recognized as areas of potential improvement in the management of acromegaly, in addition to participation in national and regional acromegaly registries. Further experience exchange will facilitate the identification of specific strategies that can be adapted in each country, and widespread participation in acromegaly registries will enable their evaluation. It is anticipated that this approach will support the optimization of acromegaly patient care across this region.

Acromegaly and cardiovascular outcomes: a cohort study

AIMS

Cardiovascular disease is a common complication in acromegaly. We investigated the risk of cardiovascular disease and mortality in patients with acromegaly in a large-scale population using nationwide data in Korea.

METHODS AND RESULTS

We performed a nationwide, retrospective, observational, cohort study of patients with acromegaly (n = 1874) and age- and sex-matched subjects without acromegaly (n = 9370) for a mean follow-up of 7.5 ± 3.2 years. The study outcomes were myocardial infarction, stroke, atrial fibrillation, congestive heart failure, and all-cause death. All outcomes were analysed by Cox proportional hazards regression analysis while controlling for age, sex, household income, place, Type 2 diabetes, hypertension, and dyslipidaemia. The incidence (per 1000 person-years) of atrial fibrillation (3.06 vs. 1.70; P = 0.001), congestive heart failure (3.11 vs. 1.63; P < 0.001), and all-cause mortality (6.31 vs. 4.03; P < 0.001) in patients with acromegaly was higher than in controls. However, the incidence of myocardial infarction and stroke did not differ between groups. After adjustment for covariates, the risk for atrial fibrillation [hazard ratio (HR): 1.59; 95% confidence interval (CI): 1.09-2.31], congestive heart failure (HR: 1.54; 95% CI: 1.06-2.25), and all-cause mortality (HR: 1.31; 95% CI: 1.01-1.69) was significantly higher in patients with acromegaly. In time lag sensitivity analysis, a higher risk for atrial fibrillation was observed only in the first 4 years after diagnosis in acromegaly patients compared with controls (HR: 3.05; 95% CI: 1.94-4.79).

CONCLUSION

Patients with acromegaly were at higher risk for atrial fibrillation, congestive heart failure, and all-cause death. The risk of atrial fibrillation had a time-dependent association with acromegaly.

Clinical features and complications of acromegaly at diagnosis are not all the same: data from two large referral centers

PURPOSE

The number of international acromegaly related registries is increasing; however, heterogeneity of acromegaly symptoms and signs across countries is not well described. We compared clinical disease manifestations at diagnosis between two large University referral centers from two continents.

METHODS

Retrospective, comparative epidemiological study of acromegaly patients at two centers: (i) C. I. Parhon National Institute of Endocrinology, 'Carol Davila' University of Medicine and Pharmacy Bucharest, Romania (Parhon), and (ii) Pituitary Center, Oregon Health & Science University, Portland, Oregon, United States (OHSU) from approved data repositories was undertaken. Data were extracted from medical charts and questionnaires. Binary logistic regression analysis was undertaken for the most frequently noted symptoms and clinical signs.

RESULTS

The study included 216 patients (87 Parhon, 129 OHSU). Age, sex, and median delay in diagnosis were similar between centers. IGF-1 index was higher in patients at Parhon (3.3 vs 2.1, P < 0.001). The top five symptoms at both centers were enlarged hands/feet, headache, arthralgia, fatigue, and irregular menses in women. A significant difference was noted for multiple signs and symptoms frequency, often > 20 percentage points between centers. Center was a predictor of many signs and symptoms, independent of acromegaly biochemical severity or disease duration.

CONCLUSION

We show in the first comparative study that differences in medical practice, documentation, and likely cultural differences can influence patients' symptom(s) reporting and screening patterns in geographically different populations. Pooling data into large multicenter international registry databases may lead to loss of regional characteristics and thus a mixed overall picture of combined cohorts.

Advances in Research on the Cardiovascular Complications of Acromegaly

Cardiovascular-related complications are one of the most common complications in patients with acromegaly, and can lead to an increased risk of death. Hypertension and cardiomyopathy are the main cardiovascular complications. The characteristics of acromegalic cardiomyopathy are concentric biventricular hypertrophy and diastolic dysfunction. In addition, arrhythmia and heart valve disease are common cardiac complications in acromegaly. Although the underlying pathophysiology has not been fully elucidated, the spontaneous overproduction of GH and IGF-1, increasing age, prolonged duration of disease and the coexistence of other cardiovascular risk factors are crucial to cardiac complications in patients with acromegaly. Early diagnosis and appropriate treatment of acromegaly might be beneficial for the prevention of cardiomyopathy and premature death.

Mortality in Acromegalic Patients: Etiology, Trends, and Risk Factors

Although acromegaly has been associated with increased mortality rates, evidence shows that the application of the recent treatment modalities has reduced the risk of death in these patients, being comparable with the general population. As a result of the changing trends regarding mortality, the aim is to review the current literature to create enough evidence about the recent trends of mortality in patients with acromegaly. Moreover, this review aims to identify the possible etiology and the related risk factors. Old studies have reported that cardiovascular complications were the major etiology for death among acromegalic patients. However, recent studies showed that malignancies-induced complications might be the leading factor, while other studies reported that cardiovascular complications are still the main culprit. Nonetheless, the recently estimated risk is similar to that in the general population. Studies reported a decrease in mortality rates among patients with acromegaly within the last decades, which is probably attributable to the recent changes in the management updates, the less frequent exposure to radiotherapy and focus on the common cardiovascular disorders associated with the disease. This review also found that exposure to radiotherapy, old age, hypopituitarism, active acromegaly, and high growth hormone (GH) levels are significant predictors of mortality in acromegalic patients. In conclusion, more effort should be made to decrease GH to favorable levels based on the recent guidelines.

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.

New Epidemiological, Clinical and Economic Data for Patients With Acromegaly in Bulgaria

Background: Acromegaly and its comorbidities affect the patients' quality of life, each healthcare system and the society. This study aimed to evaluate clinical characteristics and treatment patterns and the economic burden of acromegaly.

Materials and methods: All patients with acromegaly treated with expensive medicines and regularly followed up at the main expert clinical center for acromegaly in the country were included in this nationwide, retrospective, observational, population-based study. Patient characteristics, treatment patterns, healthcare resource use, and costs were assessed for 1-year period (01.01.2018–31.12.2018). Results were processed through statistical analysis using MedCalc software version 16.4.1.

Results: A total of 191 acromegaly patients were observed. Approximately 67% were female, 45.5% were between 41 and 60 years and the mean age at diagnosis was 40.73 years. Surgical treatment was preferred as a first-line therapy among almost 89% of all diagnosed patients. The level of comorbidities was very high as more than 95% suffered from at least one concomitant disease. The most frequent comorbidities were other endocrine and metabolic diseases (96.7%), followed by cardiovascular diseases (70.7%). The most common first-line pharmacotherapy was long-acting somatostatin analogs (SSA) (38%) followed by dual combination SSA + pegvisomant (21%). The total economic burden of acromegaly was estimated to be 2,674,499.90 € in 2018 as the direct costs (medication costs, hospitalization costs covered by the patients and the National Health Insurance Fund) outnumbered indirect costs (loss of productivity due to hospitalization): 2,630,568.58 € vs. 43,931.32 €. The average annual per-patient direct and indirect costs were 14,002.62 €.

Conclusions: The current study demonstrates a significant clinical and socio-economic burden of acromegaly in the country. Proper diagnosing and regular follow up of acromegaly patients in a specialized pituitary center ensure appropriate innovative pharmacotherapy with achievement of disease control.

Determinants of morbidities and mortality in acromegaly

Acromegaly is a systemic disease associated with increased morbidity, presenting cardiovascular, metabolic, respiratory, neoplastic, endocrine, articular and bone complications. Most of these comorbidities can be prevented or delayed with adequate disease treatment and, more recent studies with the use of modern treatments of acromegaly, have shown a change in the severity and prevalence of these complications. In addition, acromegaly is associated with increased mortality, but recent studies (especially those published in the last decade) have shown a different scenario than older studies, with mortality no longer being increased in adequately controlled patients and a change in the main cause of death from cardiovascular disease to malignancy. In this review, we discuss this changing face of acromegaly summarizing current knowledge and evidence on morbimortality of the disease. Arch Endocrinol Metab. 2019;63(6):630-7.

Acromegaly and Heart Failure

In patients with acromegaly, chronic GH and IGF-I excess commonly causes a specific cardiomyopathy characterized by a concentric cardiac hypertrophy associated with diastolic dysfunction and, in later stages, with systolic dysfunction ending in heart failure in untreated and uncontrolled patients. Additional relevant cardiovascular complications are represented by arterial hypertension, valvulopathies, arrhythmias, and vascular endothelial dysfunction, which, together with the respiratory and metabolic complications, contribute to the development of cardiac disease and the increase cardiovascular risk in acromegaly. Disease duration plays a pivotal role in the determination of acromegalic cardiomyopathy. The main functional disturbance in acromegalic cardiomyopathy is the diastolic dysfunction, observed in 11% to 58% of patients, it is usually mild, without clinical consequence, and the progression to systolic dysfunction is generally uncommon, not seen or observed in less than 3% of the patients. Consequently, the presence of overt CHF is rare in acromegaly, ranging between 1 and 4%, in patients with untreated and uncontrolled disease. Control of acromegaly, induced by either pituitary surgery or medical therapy improves cardiac structure and performance, limiting the progression of acromegaly cardiomyopathy to CHF. However, when CHF is associated with dilative cardiomyopathy, it is generally not reversible, despite the treatment of the acromegaly.

National acromegaly registries

Acromegaly is a rare disease, associated with multiple organs and systems damage. Thanks to implementation of registries, systematic data gathering, knowledge sharing and standardizing medical practices for optimal care greatly improved. Data concerning 19 national acromegaly registries are available, involving more than 16,000 patients. The weighted mean age of diagnosis is 45.2 years and seems stable over time. A macroadenoma is found in 75% of the cases. The proportion of patients operated (>80%) did not change along time. By contrast, use of radiotherapy has decreased while use of medical therapy increased. If judged on IGF-I levels, acromegaly is controlled in 61.3% of the patients. The disease control rate has improved over time. This is likely due to the development of medical treatment strategies. The collection of data about comorbidities in national registries is much less comprehensive than those about epidemiology, disease control or treatment strategies. The most reported comorbidities are arterial hypertension and diabetes. Data concerning mortality trends are controversial. It seems that cancer has become a leading cause of death in acromegaly patients in the last decade, period in which life expectancy improved, while cardiovascular mortality decreased. In conclusion, acromegaly registries offer a global view of the disease with no "a priori" assumptions. This is of outmost importance, because of the large amount of data and the huge number of associated comorbidities. This will help to establish guidelines for management of this rare disease.

Growth Hormone's Links to Cancer

Several components of the GH axis are involved in tumor progression, and GH-induced intracellular signaling has been strongly associated with breast cancer susceptibility in genome-wide association studies. In the general population, high IGF-I levels and low IGF-binding protein-3 levels within the normal range are associated with the development of common malignancies, and components of the GH-IGF signaling system exhibit correlations with clinical, histopathological, and therapeutic parameters in cancer patients. Despite promising findings in preclinical studies, anticancer therapies targeting the GH-IGF signaling system have led to disappointing results in clinical trials. There is substantial evidence for some degree of protection against tumor development in several animal models and in patients with genetic defects associated with GH deficiency or resistance. In contrast, the link between GH excess and cancer risk in acromegaly patients is much less clear, and cancer screening in acromegaly has been a highly controversial issue. Recent studies have shown that increased life expectancy in acromegaly patients who attain normal GH and IGF-I levels is associated with more deaths due to age-related cancers. Replacement GH therapy in GH deficiency hypopituitary adults and short children has been shown to be safe when no other risk factors for malignancy are present. Nevertheless, the use of GH in cancer survivors and in short children with RASopathies, chromosomal breakage syndromes, or DNA-repair disorders should be carefully evaluated owing to an increased risk of recurrence, primary cancer, or second neoplasia in these individuals.

Acromegaly

Acromegaly is characterized by increased release of growth hormone and, consequently, insulin-like growth factor I (IGF1), most often by a pituitary adenoma. Prolonged exposure to excess hormone leads to progressive somatic disfigurement and a wide range of systemic manifestations that are associated with increased mortality. Although considered a rare disease, recent studies have reported an increased incidence of acromegaly owing to better disease awareness, improved diagnostic tools and perhaps a real increase in prevalence. Acromegaly treatment approaches, which include surgery, radiotherapy and medical therapy, have changed considerably over time owing to improved surgical procedures, development of new radiotherapy techniques and availability of new medical therapies. The optimal use of these treatments will reduce mortality in patients with acromegaly to levels in the general population. Medical therapy is currently an important treatment option and can even be the first-line treatment in patients with acromegaly who will not benefit from or are not suitable for first-line neurosurgical treatment. Pharmacological treatments include somatostatin receptor ligands (such as octreotide, lanreotide and pasireotide), dopamine agonists and the growth hormone receptor antagonist pegvisomant. In this Primer, we review the main aspects of acromegaly, including scientific advances that underlie expanding knowledge of disease pathogenesis, improvements in disease management and new medical therapies that are available and in development to improve disease control.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.

Health-Related Complications of Acromegaly-Risk of Malignant Neoplasms

The issue of increased risk of benign and malignant neoplasms in patients with acromegaly remains the topic of debate from many years and was addressed by numerous studies. Many of them have shown increase in the cancer incidence. Among particular types of malignancies, thyroid, colorectal, and breast cancer are most commonly indicated as associated with acromegaly. Single reports denoted increase in prevalence of neoplasms of other organs such as kidney, bone or central nervous system. Cardiovascular and respiratory tract disorders were traditionally consider as main causes of mortality in acromegalic patients, accounting for about 60 and 25% of deaths, respectively. However, according to a number of studies published over the current decade cancer became the most important cause of deaths. Aim of the current article was to review the literature concerning the risk of malignant neoplasms in acromegaly and its clinical implications.

Mortality in acromegaly decreased in the last decade: a systematic review and meta-analysis

OBJECTIVE

To compare the acromegaly mortality rates with those expected for the general population from studies published before and after 2008.

METHODS

We performed a systematic review and included observational studies in which the number of deaths observed in acromegaly was compared with the expected mortality for the general population mortality observed/expected (O/E). The following electronic databases were used as our data sources: EMBASE, MEDLINE and LILACS. From the observed and expected deaths, we recalculated all standardized mortality ratios (SMR) and their respective confidence intervals (95% CI), which were plotted in a meta-analysis using the software RevMan 5.3.

RESULTS

We identified 2303 references, and 26 studies fulfilled our eligibility criteria. From the 17 studies published before 2008, the mortality in acromegaly was increased, while from the nine studies published after 2008, the mortality was not different from the general population (SMR: 1.35, CI: 0.99-1.85). In six studies where somatostatin analogs (SAs) were used as adjuvant treatment, acromegaly mortality was not increased (SMR: 0.98, CI: 0.83-1.15), whereas in series including only patients treated with surgery and/or radiotherapy, mortality was significantly higher (SMR: 2.11; CI: 1.54-2.91). In studies published before and after 2008, the mortality was not increased in patients who achieved biochemical control, while it was higher in those with active disease. Cancer has become a leader cause of deaths in acromegaly patients in the last decade, period in which life expectancy improved.

CONCLUSION

Mortality in acromegaly is normalized with biochemical control and decreased in the last decade with the more frequent use of SAs as adjuvant therapy. Increased life expectancy has been associated with more deaths due to cancer.

Updates in outcomes of stereotactic radiation therapy in acromegaly

Purpose Treatment of acromegaly has undergone important progress in the last 20 years mainly due to the development of new medical options and advances in surgical techniques. Pituitary surgery is usually first-line therapy, and medical treatment is indicated for persistent disease, while radiation (RT) is often used as third-line therapy. The benefits of RT (tumor volume control and decreased hormonal secretion) are hampered by the long latency of the effect and the high risk of adverse effects. Stereotactic RT methods have been developed with the aim to provide more precise targeting of the tumor with better control of the radiation dose received by the adjacent brain structures. The purpose of this review is to present the updates in the efficacy and safety of pituitary RT in acromegalic patients, with an emphasis on the new stereotactic radiation techniques. Methods A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in acromegaly from 2000 to 2016 were included. Results Stereotactic radiosurgery and fractionated stereotactic RT (FSRT) for patients with persistent active acromegaly after surgery and/or during medical therapy provide comparable high rates of tumor control, i.e. stable or decrease in size of the tumor in 93-100% of patients at 5-10 years and endocrinological remission in 40-60% of patients at 5 years. Hypofractionated RT is an optimal option for tumors located near the optic structures, due to its lower toxicity for the optic nerves compared to single-dose radiosurgery. The rate of new hypopituitarism varies from 10 to 50% at 5 years and increases with the duration of follow-up. The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and 0-1% for secondary brain tumors) and risk of stroke may be higher in FSRT. Conclusion Although the use of radiotherapy in patients with acromegaly has decreased with advances in medical treatments, it remains an effective treatment option after unsuccessful surgery and/or resistance or unavailability of medical therapy. Long-term studies evaluating secondary morbidity and mortality rate after the new stereotactic techniques are needed, in order to evaluate their potential brain-sparing effect.

STEREOTACTIC RADIATION THERAPY IN PITUITARY ADENOMAS, IS IT BETTER THAN CONVENTIONAL RADIATION THERAPY?

Pituitary radiotherapy (RT) has undergone important progress in the last decades due to the development of new stereotactic techniques which provide more precise tumour targeting with less overall radiation received by the adjacent brain structures. Pituitary surgery is usually first-line therapy in most patients with nonfunctioning (NFPA) and functioning adenomas (except for prolactinomas and large growth hormone (GH) secreting adenomas), while RT is used as second or third-line therapy. The benefits of RT (tumour volume control and, in functional tumours, decreased hormonal secretion) are hampered by the long latency of the effect and the potential side effects. This review presents the updates in the efficacy and safety of the new stereotactic radiation techniques in patients with NFPA, GH-, ACTH- or PRL-secreting pituitary adenomas.

Methods

A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in pituitary adenomas from 2000 to 2017 were included.

Results

Stereotactic radiosurgery (SRS) and fractionated stereotactic RT (FSRT) provide high rates of tumour control i.e. stable or decrease in tumour size, in all types of pituitary adenomas (median 92 - 98%) at 5 years. Endocrinological remission is however significantly lower: 44-52% in acromegaly, 54-64% in Cushing's disease and around 30% in prolactinomas at 5 years. The rate of new hypopituitarism varies from 10% to 50% at 5 years in all tumour types and as expected increases with the duration of follow-up (FU). The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and extremely low for secondary brain tumours), however longer FU is needed to determine rates of secondary tumours. Notably, in acromegaly, there may be a higher risk for stroke with FSRT.

Conclusion

Stereotactic radiotherapy can be an effective treatment option for patients with persistent or recurrent pituitary adenomas after unsuccessful surgery (especially if residual tumour is enlarging) and/or resistance or unavailability of medical therapy. Comparison with conventional radiation therapy (CRT) is rather difficult, due to the substantial heterogeneity of the studies. In order to evaluate the potential brain-sparing effect of the new stereotactic techniques, suggested by the current data, long-term studies evaluating secondary morbidity and mortality are needed.

Mortality in acromegaly: a 20-year follow-up study

OBJECTIVE

It is unclear whether mortality still is increased in acromegaly and whether there are gender-related differences. We dynamically assessed outcome during long-term follow-up in our nationwide cohort.

PATIENTS AND METHODS

We studied standardized mortality ratios (SMRs) relative to the general population and causes of death in acromegaly (n=333) compared with age- and gender-matched controls (n=4995).

RESULTS

During 20 (0-33) years follow-up, 113 (34%) patients (n=333, 52% women) and 1334 (27%) controls (n=4995) died (P=0.004). SMR (1.9, 95% CI: 1.53-2.34, P<0.001) and all-cause mortality (OR 1.6, 95% CI: 1.2-2.2, P<0.001) were increased in acromegaly. Overall distribution of causes of death (P<0.001) differed between patients and controls but not cardiovascular (34% vs 33%) or cancer deaths (27% vs 27%). In acromegaly, but not in controls, causes of deaths shifted from 44% cardiovascular and 28% cancer deaths during the first decade, to 23% cardiovascular and 35% cancer deaths during the next two decades. In acromegaly, cancer deaths were mostly attributed to pancreatic adenocarcinoma (n=5), breast (n=4), lung (n=3) and colon (n=3) carcinoma. In acromegaly, men were younger than women at diagnosis (median 44.5 vs 50 years, P<0.001) and death (67 vs 76 years, P=0.0015). Compared with controls, women (36% vs 25%, P<0.01), but not men (31% vs 28%, P=0.44), had increased mortality.

CONCLUSIONS

In acromegaly, men are younger at diagnosis and death than women. Compared with controls, mortality is increased during 20 years of follow-up, especially in women. Causes of deaths shift from predominantly cardiovascular to cancer deaths.

Outcome of complications in acromegaly patients after long-term disease remission

Acromegaly patients suffer from pathologically high growth hormone (GH) and IGF-1 levels that in 99% of cases is due to a GH-producing pituitary adenoma. During active disease, GH excess is associated with a number of pathological conditions, such as hypertension, hypertrophic cardiomyopathy, sleep apnea, arthropathy, vertebral fractures and insulin resistance. After adequate treatment in the form of transsphenoidal surgery, radiotherapy, medical treatment or by a combination of these treatment modalities, several comorbid conditions improve considerably. However, despite long-term biochemical disease control, the prevalence of late manifestations of GH excess is high and significantly impair quality of life. In addition, there is evidence that adequate treatment is not able to normalize mortality risk in these patients. In this review, we critically evaluate the long-term consequences of acromegaly after treatment, focusing on comorbid conditions, quality of life and mortality. We also discuss ongoing challenges in the management of acromegaly patients.