MANAGEMENT OF ENDOCRINE DISEASE: GH excess: diagnosis and medical therapy

Abstract

Acromegaly is predominantly caused by a pituitary adenoma, which secretes an excess of GH resulting in increased IGF1 levels. Most of the GH assays used currently measure only the levels of the 22 kDa form of GH. In theory, the diagnostic sensitivity may be lower compared with the previous assays, which have used polyclonal antibodies. Many GH-secreting adenomas are plurihormonal and may co-secrete prolactin, TSH and a-subunit. Hyperprolactinaemia is found in 30-40% of patients with acromegaly, and hyperprolactinaemia may occasionally be diagnosed before acromegaly is apparent. Although trans-sphenoidal surgery of a GH-secreting adenoma remains the first treatment at most centres, the role of somatostatin analogues, octreotide long-acting repeatable and lanreotide Autogel as primary therapy is still the subject of some debate. Although the normalisation of GH and IGF1 levels is the main objective in all patients with acromegaly, GH and IGF1 levels may be discordant, especially during somatostatin analogue therapy. This discordance usually takes the form of high GH levels and an IGF1 level towards the upper limit of the normal range. Pasireotide, a new somatostatin analogue, may be more efficacious in some patients, but the drug has not yet been registered for acromegaly. Papers published on pasireotide have reported an increased risk of diabetes mellitus due to a reduction in insulin levels. Pegvisomant, the GH receptor antagonist, is indicated -alone or in combination with a somatostatin analogue -in most patients who fail to enter remission on a somatostatin analogue. Dopamine-D2-agonists may be effective as monotherapy in a few patients, but it may prove necessary to apply combination therapy involving a somatostatin analogue and/or pegvisomant.

Akromegalia — nowe spojrzenie na pacjenta. Polskie propozycje postępowania diagnostyczno-terapeutycznego w akromegalii w świetle aktualnych doniesień

“…Random GH level below 1.0 µg/L allows the exclusion of active acromegaly [2,11,12]. At the diagnosis of the disease, it is also necessary to evaluate the presence and degree of its systemic complications and metabolic disorders (Table II).…”

“…The secondary aim is to remove or significantly reduce the mass of the pituitary tumour which should result in an improvement of disorders associated with its expansion. Both objectives can be achieved by surgical and pharmacological treatment, and, less frequently, radiotherapy [6,11,13,14].…”

Hipofizer Gigantizm: Olgu Sunumu

“…Cerrahi tedavi için uygun olmayan ve cerrahi ile hastalığı kontrol altına alınamayan çocuklarda ilaç tedavisi uygulanabilir. Somatostatin analogları (oktreotid, lantreotid), BH reseptör antagonisti (pegvisomat) ve dopamin agonistleri (bromokriptin, kabergolin) gigantizm tedavisinde kullanılan farmakolojik ajanlardır (11). Son yıllarda yeni bir somatostatin analoğu pasireotid ile akromegali hastalarında yüz güldürücü sonuçlar alınmıştır (19).…”

“…Mikro-ve makrodenomların tedavisinde ilk seçenek transsfenoidal cerrahidir (10). Cerrahi ile kontrol altına alınamayan veya cerrahinin uygulanamadığı hastalarda tedavi seçenekleri; dopamin analogları, somatostatin analogları ve BH reseptör antagonistleri gibi farmakolojik ajanlardır (11). Radyoterapi ciddi komplikasyon riskleri nedeniyle çocuklarda tercih edilmemektedir.…”

Curative Result with Primary Medical Therapy in an Elderly Acromegaly Patient

“…Medical treatment is not preferred because patients with microadenoma have a high chance of cure with surgery and it is controversial before surgery to positive contribution to the course of disease in macroadenomas. Although often needed in medical treatment as adjuvant, conventional fractionated radiotherapy, stereotactic radio-surgery (Gamma Knife surgery included), Cyber Knife treatment or radiotherapy in the form of proton-beam is less needed in patients with acromegaly [5].  After surgery; in cases of biochemical control cannot be achieved [9],  Before surgery; to reduce the complications of operation by ensuring the healing of serious co morbid conditions (not proven) [10],  In patients who underwent radiotherapy; to ensure that the disease is under control until the time that the effect of radiotherapy can be seen [11].…”