Updates in Diagnosis and Treatment of Acromegaly

Acromegaly is a chronic disorder characterized by growth hormone (GH) hypersecretion,and more than 95% of acromegalic cases are secondary to a pituitary adenoma. Hypersecretion of GH leads to excess production of IGF-1, which mediates most of the phenotypic features and metabolic effects of GH, but GH excess also has direct detrimental effects. Recent studies showed that a large number of patients with acromegaly can have a very different clinical, biochemical and radiological presentation compared with what is considered a ‘classical’ one. In this lecture, we are going to focus on several recent updates related to acromegaly diagnosis and treatment. Acromegaly screening is initiated with biochemical tests. Recently-published guidelines recommend using age- and sex-adjusted IGF-1 levels in combination with GH nadir during an oralglucose tolerance test (OGTT) to diagnose and rule out acromegaly. The biological and analytical variability of these biochemical markers will be discussed at the lecture.After GH hypersecretion has been confirmed, pituitary magnetic resonance imaging (MRI) is recommended to determine the source of GH hypersecretion. Certain radiologic characteristics have been recently recognized as markers for disease behaviour and predictors of response to therapy, which will be explained during the speech.The new grading of pituitary adenomas, updated by WHO in 2017 emphasized the evaluation of morphology, tumor proliferation and invasion status for prognostication and evaluation of aggressiveness of the adenomas. We will briefly discuss the different types of pituitary adenomas regarding the pathological features. Transsphenoidal pituitary adenoma resection is generally the first-line therapy. However, acromegaly treatment is frequently multimodal. Pharmacologic agents available for treatment of acromegaly include somatostatin-receptor ligands (SRLs), GH-receptor antagonists and, in selected cases, dopamine agonists. The different strategies for pharmacologic treatment are the next topic which will be explained during the lecture. Radiation therapy is the third-line treatment algorithm for acromegaly, and is usually considered in cases of large residual (or enlarging) tumor following surgery, and if medical therapy is unsuccessful or not tolerated.In conclusion, novel insights into the diagnosis and pathophysiology of acromegaly have been acquired over recent years, and there are several new therapies in development, including new delivery systems, or prolonged release medications. Expanded knowledge on the histological and molecular levels, and development of new markers of response and resistance to SRL emphasized the importance of a personalized approach rather than following a universal algorithm for therapy. The treatment of acromegaly remains multimodal for most patients and a multidisciplinary team is essential for optimal disease management and outcome.