The value of an acute octreotide suppression test in predicting short-term efficacy of somatostatin analogues in acromegaly.

Abstract

Predicting the efficacy of long-acting somatostatin analogues (SSA) remains a challenge. We aim to quantitatively evaluate the predictive value of the octreotide suppression test (OST) in short-term efficacy of SSA in active acromegaly. Sixty-seven newly diagnosed acromegaly patients were assessed with OST. Subsequently, all patients were treated with long-acting SSA for 3 months, followed by reassessment. Nine parameters were tested, including GHn (the nadir GH during OST), ΔGH1 (= [GH0h-GHn]/GH0h, GH0h was the baseline GH during OST), ΔGH2 (= [GHm-GHn]/GHm, GHm was the mean GH on day curve), AUC(0-6h) (the GH area under the curve during OST) , ΔAUC1 (= [GH0h-AUC(0-6h)]/GH0h), ΔAUC2 (=[GHm-AUC(0-6h)]/GHm), AUC(m-6h) (the GH AUC during OST where GHm was used instead of GH0h), ΔAUC1' (=[GH0h-AUC(m-6h)]/GH0h) and ΔAUC2' (=[GHm-AUC(m-6h)]/GHm). The Youden indices were calculated to determine the optimal cutoffs to predict the short-term efficacy of SSA. ΔGH2 more than 86.83%, ΔAUC2 more than -57.48% and ΔAUC2' more than -57.98% provided the best predictors of a good GH response (sensitivity 93.8%, specificity 85.7%). ΔGH2 more than 90.51% provided the best predictor of a good tumor size response (sensitivity 84.8%, specificity 87.5%). The percentage fall of GHn (ΔGH) was a better predictive parameter than GHn. OST showed higher efficiency in predicting the efficacy of octreotide LAR than lanreotide SR. In conclusion, OST is a valid tool to predict both GH and tumor size response to short-term efficacy of SSA in acromegaly, especially for octreotide LAR. GHm is better to be used as basal GH than GH0 during OST.

• Authors: Meng Wang, Ming Shen, Wenqiang He, Yeping Yang, Wenjuan Liu, Yun Lu, Zengyi Ma, Zhao Ye, Yichao Zhang, Xiaolong Zhao, Bin Lu, Ji Hu, Yun Huang, Xuefei Shou, Yongfei Wang, Hongying Ye, Yiming Li, Shiqi Li, Yao Zhao, Zhaoyun Zhang
• Journal: Endocrine journal (Endocr J) Vol. 63 Issue 9 Pg. 819-834 (Sep 30 2016) ISSN: 1348-4540 [Electronic] Japan
• PMID: 27432816 (Publication Type: Evaluation Study, Journal Article)

Chemical References

• Antineoplastic Agents, Hormonal
• Somatostatin
• Octreotide

Topics

• Acromegaly (diagnosis, drug therapy, etiology)
• Adenoma (complications, diagnosis, drug therapy)
• Adult
• Antineoplastic Agents, Hormonal (therapeutic use)
• Diagnostic Techniques, Endocrine
• Female
• Growth Hormone-Secreting Pituitary Adenoma (complications, diagnosis, drug therapy)
• Humans
• Male
• Middle Aged
• Octreotide (pharmacology)
• Predictive Value of Tests
• Prognosis
• Retrospective Studies
• Sensitivity and Specificity
• Somatostatin (analogs & derivatives)
• Treatment Outcome