Prolactinomas are the most commonly encountered pituitary adenomas in the clinical setting. While most can be controlled by dopamine agonists, a subset of prolactinomas are dopamine-resistant and very aggressive. In such tumors, the treatment of choice is neurosurgery and radiotherapy, with or without temozolomide. Here, we report a patient with an highly aggressive, dopamine-resistant prolactinoma, who only achieved biochemical and tumor control during pasireotide long-acting release (PAS-LAR) therapy, a second-generation somatostatin receptor ligand (SRL). Interestingly, cystic degeneration, tumor cell necrosis or both was observed after PAS-LAR administration suggesting an antitumor effect. This case shows that PAS-LAR therapy holds clinical potential in selective aggressive, dopamine-resistant prolactinomas that express somatostatin (SST) receptor subtype 5 and appears to be a potential new treatment option before starting temozolomide. In addition, PAS-LAR therapy may induce cystic degeneration, tumor cell necrosis or both in prolactinomas.

doi.org/10.1530/EJE-19-0279, hdl.handle.net/1765/118075
European Journal of Endocrinology
Department of Internal Medicine

Coopmans, E.C. (Eva C), Van Meyel, S.W.F. (Sebastiaan W F), Pieterman, K., Van Ipenburg, J.A. (Jolique A), Hofland, L., Donga, E. (Esther), … Neggers, S.J.C.M.M. (Sebastian J C M M). (2019). Excellent response to pasireotide therapy in an aggressive and dopamine-resistant prolactinoma. European Journal of Endocrinology, 181(2), K21–K27. doi:10.1530/EJE-19-0279