Pegvisomant and pasireotide in PRL and GH co-secreting vs GH-secreting Pit-NETs

Endocr Relat Cancer. 2024 May 27;31(7):e240043. doi: 10.1530/ERC-24-0043. Print 2024 Jul 1.


The objective of the study was to evaluate the efficacy of second-line therapies in patients with acromegaly caused by a growth hormone (GH) and prolactin (PRL) co-secreting pituitary neuroendocrine tumor (GH&PRL-Pit-NET) compared to their efficacy in patients with acromegaly caused by a GH-secreting pituitary neuroendocrine tumor (GH-Pit-NET). This is a multicenter retrospective study of patients with acromegaly on treatment with pasireotide and/or pegvisomant. Patients were classified in two groups: GH&PRL-Pit-NETs when evidence of hyperprolactinemia and immunohistochemistry (IHC) for GH and PRL was positive or if PRL were >200 ng/dL regardless of the PRL-IHC and GH-Pit-NETs when the previously mentioned criteria were not met. A total of 28 cases with GH&PRL-Pit-NETs and 122 with GH-Pit-NETs met the inclusion criteria. GH&PRL-Pit-NETs presented at a younger age, caused hypopituitarism, and were invasive more frequently than GH-Pit-NETs. There were 124 patients treated with pegvisomant and 49 with pasireotide at any time. The efficacy of pegvisomant for IGF-1 normalization was of 81.5% and of pasireotide of 71.4%. No differences in IGF-1 control with pasireotide and with pegvisomant were observed between GH&PRL-Pit-NETs and GH-Pit-NETs. All GH&PRL-Pit-NET cases treated with pasireotide (n = 6) and 82.6% (n = 19/23) of the cases treated with pegvisomant normalized PRL levels. No differences in the rate of IGF-1 control between pegvisomant and pasireotide were detected in patients with GH&PRL-Pit-NETs (84.9% vs 66.7%, P = 0.178). We conclude that despite the more aggressive behavior of GH&PRL-Pit-NETs than GH-Pit-NETs, no differences in the rate of IGF-1 control with pegvisomant and pasireotide were observed between both groups, and both drugs have shown to be effective treatments to control IGF-1 and PRL hypersecretion in these tumors.

Keywords: acromegaly; pasireotide; pegvisomant; pituitary neuroendocrine tumors; prolactin.

Publication types

  • Multicenter Study

MeSH terms

  • Acromegaly* / drug therapy
  • Acromegaly* / metabolism
  • Adult
  • Aged
  • Female
  • Human Growth Hormone* / analogs & derivatives
  • Human Growth Hormone* / therapeutic use
  • Humans
  • Male
  • Middle Aged
  • Neuroendocrine Tumors* / drug therapy
  • Neuroendocrine Tumors* / metabolism
  • Pituitary Neoplasms / drug therapy
  • Pituitary Neoplasms / metabolism
  • Prolactin* / blood
  • Prolactin* / metabolism
  • Retrospective Studies
  • Somatostatin* / analogs & derivatives
  • Somatostatin* / therapeutic use
  • Young Adult


  • pasireotide
  • pegvisomant
  • Somatostatin
  • Human Growth Hormone
  • Prolactin