Results of surgical and somatostatin analog therapies and their combination in acromegaly: a retrospective analysis of the German Acromegaly Register

Abstract

Background: Data on surgical and medical treatment outcomes in acromegaly mostly originate from specialized centers. We retrospectively analyzed the data on surgery, primary somatostatin analog (SSA) therapy, surgery preceded by SSA, and SSA preceded by surgery in 1485 patients from the German Acromegaly Register. Methods: Two trained nurses visited all centers (NZ42) for data acquisition. Results: Primary surgery: out of 889 patients, 554 yielded analyzable data (microadenomas 22.9%, macroadenomas 77.1%). GH and IGF1 normalized in 54.3 and 67.2%. Partial or total pituitary insufficiency occurred in 28.6% initially and 41.2% post-surgery. Primary SSA (R3 months): out of 329 patients, 145 yielded analyzable data (microadenomas 26.7%, macroadenomas 73.3%). GH and IGF1 normalized in 36.3 and 30.5%, increasing to 40.8 and 41.5% with longer SSA (R360 days) in 54 patients. Pituitary function did not change. SSA (R3 months) prior to surgery: out of 234 patients, 93 yielded analyzable data. Post-surgery GH and IGF1 was normalized in 62.9 and 68.4%. GH improvement was slightly, but significantly better after SSA pretreatment. Surgery followed by SSA: out of 122 patients, 34 yielded analyzable data. GH and IGF1 normalized during SSA in 24.1 and 45.5%. Relative GH decrease was significantly larger compared with primary SSA. Conclusions: Pituitary surgery was more effective to lower GH and IGF1 concentrations than primary SSA. Primary SSA may be an option in selected patients. SSA prior to surgery only marginally improved surgical outcome. Debulking surgery may result in better final outcome in patients with a high GH concentration and a large tumor.

Long-term outcome in patients with acromegaly: analysis of 1344 patients from the German Acromegaly Register

“…Based on a population of about 80 million and a disease prevalence of about 40-60 cases/million (31,32), this cohort represents w30-40% of all acromegalic patients in Germany. The proportion of patients treated either in university or non-university hospitals or in private endocrine practices was similar to previous reports from the German Register (25,26). We assume that this is a representative picture of endocrine specialist care for patients with acromegaly in Germany.…”

“…The register performs an epidemiological, retrospective study on the diagnosis, treatment, and follow-up of patients with acromegaly in Germany. Details about the structure, database, and data collection have been published previously (19,25,26). Written informed consent has been obtained from the patients included in the present survey.…”

An update on the treatment of acromegaly

“…GH and IGF-1 normalized in 54.3% and 67.2% of surgical patients compared to 40.8% and 41.5% of patients treated with somatostatin analogs for at least 1 year. 44 The latter study supports the place of surgery as the mainstay of treatment in acromegaly; however, primary therapy with somatostatin analogs is a viable option for patients who are poor surgical candidates, have unresectable tumors, or decline surgery.…”

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 view of the importance of diagnosing acromegaly and not delaying the diagnosis, as well as the existence (although uncommon) of cases with normal serum IGF-1 (12,24), in some special situations it is reasonable not to rule out the disease based only on IGF-1 levels within the normal range (Table 2), but the assessment should be complemented by the measurement of GH. However, in most cases GH measurement would not be necessary to rule out the disease.…”

“…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.…”