Impact of gsp mutations in somatotroph pituitary adenomas on growth hormone response to somatostatin analogs: a meta-analysis

作者：Efstathiadou Z A^*; Bargiota A; Chrisoulidou A; Kanakis G; Papanastasiou L; Theodoropoulou A; Tigas S K; Vassiliadi D A; Alevizaki M; Tsagarakis S

来源：Pituitary, 2015, 18(6): 861-867.

DOI：10.1007/s11102-015-0662-5

• gsp mutations
• Acromegaly
• Somatostatin analogs

Objective Somatic mutations in the GNAS1 gene, which encodes the alpha-subunit of G stimulatory proteins (gsp), are frequently detected in somatotroph pituitary tumors and have been associated to specific clinical and histopathological characteristics. However, the question whether the presence of a somatic gsp mutation affects the response to somatostatin analog treatment remains unresolved.
Design Following a literature search, we performed a meta-analysis, including 8 eligible studies, in order to estimate the effect of gsp mutation on the percent reduction of growth hormone (GH) levels during an acute octreotide suppression test (OST). A total of 310 patients with acromegaly [126 gsp (+) and 184 gsp (-)] were included in the analysis.
Results The presence of the gsp mutation was related with a greater reduction in GH levels on OST [Weighted Mean Difference (WMD): 9.08 % (95 % CI, 2.73, 15.42); p = 0.005; random effects model]. There was significant heterogeneity for this effect estimate (I-2 = 58 %, p value for heterogeneity = 0.02). A sensitivity analysis after exclusion of a study with different methodology of OST provided similar estimates [WMD: 6.93 % (95 % CI, 1.40, 12.46); p = 0.01], albeit with no significant heterogeneity (I-2 = 35 %, p value for heterogeneity = 0.16).
Conclusions The present meta-analysis suggests a role for gsp mutation as a prognostic factor of treatment response to somatostatin analogs.

• 出版日期2015-12