Successful management of octreotide-insensitive thyrotropin-secreting pituitary adenoma with bromocriptine and surgery

Abstract

Rationale: Case reports concerning the value of dopamine agonists in the treatment of patients with thyrotropin-secreting pituitary adenoma (TSHoma) are limited. Herein, we present a rare case of octreotide-insensitive TSHoma responding to bromocriptine therapy. Patient concerns: A 45-year-old Chinese man was admitted to Peking Union Medical College Hospital with marked clinical manifestations of hyperthyroidism. Diagnoses: Thyroid function tests demonstrated elevated concentrations of free thyroid hormones in the presence of normal thyrotropin. Magnetic resonance imaging findings showed a pituitary microadenoma on the right side of the sellar region. Based on characteristic endocrine results and neuroimaging findings, the patient was diagnosed with TSHoma. Interventions: Most patients with TSHomas are significantly responsive to somatostatin analog treatment. However, our patient was orally administered with bromocriptine to normalize thyroid function as assessed by suppression tests conducted prior to surgery. A transsphenoidal surgery was performed by an experienced neurosurgeon for tumor removal. Outcomes: The pituitary lesion was totally resected. Following the operation, the results of thyroid function tests were immediately within reference limits. During the follow-up, there was no residual or recurrent tumor. Lessons: Attention should be paid to the role of dopamine agonists such as bromocriptine and cabergoline as adjuvant therapy for TSHomas that are insensitive to traditional medical treatment by somatostatin analogs.