Management of acromegaly in Latin America: expert panel recommendations

Abstract

Although there are international guidelines orienting physicians on how to manage patients with acromegaly, such guidelines should be adapted for use in distinct regions of the world. A panel of neuroendocrinologists convened in Mexico City in August of 2007 to discuss specific considerations in Latin America. Of major discussion was the laboratory evaluation of acromegaly, which requires the use of appropriate tests and the adoption of local institutional standards. As a general rule to ensure diagnosis, the patient’s GH level during an oral glucose tolerance test and IGF-1 level should be evaluated. Furthermore, to guide treatment decisions, both GH and IGF-1 assessments are required. The treatment of patients with acromegaly in Latin America is influenced by local issues of cost, availability and expertise of pituitary neurosurgeons, which should dictate therapeutic choices. Such treatment has undergone profound changes because of the introduction of effective medical interventions that may be used after surgical debulking or as first-line medical therapy in selected cases. Surgical resection remains the mainstay of therapy for small pituitary adenomas (microadenomas), potentially resectable macroadenomas and invasive adenomas causing visual defects. Radiotherapy may be indicated in selected cases when no disease control is achieved despite optimal surgical debulking and medical therapy, when there is no access to somatostatin analogues, or when local issues of cost preclude other therapies. Since not all the diagnostic tools and treatment options are available in all Latin American countries, physicians need to adapt their clinical management decisions to the available local resources and therapeutic options.

Cost-Effectiveness of Somatostatin Analogues for the Treatment of Acromegaly in Colombia

“…Following the current panel recommendations for Latin America [7], we developed a payer-based decision analysis model for the treatment of acromegaly in post-surgical patients with somatostatin analogues. After surgical resection of the tumor, a hypothetical cohort of patients is assigned to start treatment with octreotide LAR (20 -30 mg) or lanreotide ATG (90 -120 mg).…”

“…Achieving these goals leads to symptom resolution and less complications and mortality rates comparable to those of the general population [4,7]. To accomplish this goal multiple interventions could be required.…”

“…Despite the guidelines and the evidence of the benefits of the treatment with somatostatin analogues for acromegaly, these treatments are not included in the mandatory health plan in Colombia [7], and their acquisition costs are high. Our aim is determine the cost-effectiveness of lanreotide and octreotide in the treatment of acromegaly in Colombia to inform decision makers and improve access to these treatments, optimizing health resources allocation.…”

Laboratory investigation of acromegaly: Is basal or random GH > 0.4 µg/L in the presence of normal serum IGF-1 an important result?

“…In the case of clinical suspicion of acromegaly, investigation is traditionally started by the measurement of IGF-1 combined with basal GH (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). The disease is ruled out if IGF-1 is normal and basal GH is less than 0.4 µg/L.…”

“…In this situation, investigation is based on GH suppression test after oral glucose overload (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). This strategy is justified by the analytical and normative limitations related to this hormone, conditions that interfere in IGF-1 measurements (reducing it), and cases of acromegaly with normal IGF-1 (5,8,12,17,18,20,23,24). Although the determination of GH concentration increases the sensitivity of patient testing, it is important to evaluate the consequences of attributing a cut-off for GH concentrations when IGF-1 is normal, i.e., to consider how many subjects are additionally submitted to the GH suppression test and pituitary imaging methods that may lead to an equivocal diagnosis.…”